# Question
Title: Why do some days feel fast and others feel slow?
As per the title, why is it some days it just feels like a day can go so fast, yet other days can feel slow? Every day has the same amount of hours, minutes and seconds after all. What is the actual science behind our state of mind when we feel like this?

# Answer
Several factors are proven to affect our experience of time. Those that differ from one day to the next include:

* **Biochemistry affects our perception of time.**

> Stimulants produce overestimates of time duration, whereas depressants and anesthetics produce underestimates of time duration. http://en.wikipedia.org/wiki/Time\_perception
* **Fear affects our perception of time:**

> Hammond points to a study in which people with arachnophobia were asked to look at spiders — the very object of their intense fear — for 45 seconds and they overestimated the elapsed time. The same pattern was observed in novice skydivers, who estimated the duration of their peers’ falls as short, whereas their own, from the same altitude, were deemed longer
>
> When a person is scared, a brain area called the amygdala becomes more active, laying down an extra set of memories that go along with those normally taken care of by other parts of the brain.
>
> "In this way, frightening events are associated with richer and denser memories," Eagleman explained. "And the more memory you have of an event, the longer you believe it took." http://www.brainpickings.org/2013/07/15/time-warped-claudia-hammond/ http://www.livescience.com/2117-time-slow-emergencies.html http://en.wikipedia.org/wiki/Time\_perception
* **Our attention affects our perception of time:**

> Wearden et al. (2014) administered a questionnaire which asked about passage of time in different drug and emotional states, and generally found that situations associated with “distraction” from time were associated with faster passage of time, in accord with the idea that “attention to time” is an important determinant of time judgements. http://www.mind-and-brain.de/postdoctoral-program/scientific-events/archive/time/
* **Having fun(or not):**

> When this was tested by Kellaris (1992), they found that when listeners enjoyed the music more, time seemed to slow down.
>
> Or—prepare yourself for a 180 degree about-face—it could all be the other way around. Perhaps you’re having fun when time flies. In other words, we assume we’ve been enjoying ourselves when we notice that time has passed quickly.
>
> There’s evidence for this in a recent experiment by Sackett et al. (2010). Participants doing a boring task were tricked into thinking it had lasted half as long as it really had. They thought it was more enjoyable than those who had been doing exactly the same task but who hadn’t been tricked about how much time had passed.
* **Being tired:**

> When we’re tired, though, our perception of time goes awry and we find it more difficult to distinguish between short spaces of time. This fact can be used to measure whether people are too tired to fly a plane, drive a truck or be a doctor. Indeed just such simple hand-held devices that quickly assess your tiredness are already being developed (Eagleman, 2009). http://www.spring.org.uk/2011/06/10-ways-our-minds-warp-time.php
* **Emotional self-regulation:**

> The effort of trying to either suppress or enhance our emotional reactions seems to change our perception of time. Psychologists have found that when people are trying to regulate their emotions, time seems to drag on.
>
> Vohs and Schmeichel (2003) had participants watch an 11 minute clip from the film Terms of Endearment. Some participants were asked to remain emotionally neutral while watching the clip and others were told to act naturally. Those who tried to suppress their emotions estimated the clip had lasted longer than it really had. http://www.spring.org.uk/2011/06/10-ways-our-minds-warp-time.php
* **Body temperature:**

> Experiments have found that when body temperature is raised our perception of time speeds up (Wearden & Pento-Voak, 1995). Conversely when we are cooled down, our sense of time also slows down. http://www.spring.org.uk/2011/06/10-ways-our-minds-warp-time.php
> 21 votes

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Tags: cognitive-psychology, time, mood
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# Question
Title: Free online survey and diary software for conducting experience sampling studies
Are there any open source online survey software that enable researchers to use experience-sampling methods, e.g. online diaries (where people answer similar survey questions repeatedly and are notified and reminded)? Free, but not open source, would also be interesting.

Please only post solutions, that you have actually used for experience-sampling research, not ones that "might be easily adapted".

# Answer
The best review of experience sampling tools I've found is here.

Specifically, to answer you question, check out "MyExperience". To quote the website:

> MyExperience is a BSD-licensed open source mobile data collection tool developed for Windows Mobile devices (including PDAs and mobile phones) using .NET CF 2 and Microsoft SQL Compact Edition.
>
> MyExperience is available for free on SourceForge in beta release. Please see our wiki for documentation and our blog for updates. MyExperience combines sensing and self-report to collect both quantitative and qualitative data on human behaviors, attitudes and activities in the field. Using a mobile phone's wireless connectivity to the internet, researchers have the ability to access MyExperience data as it's collected allowing for ongoing analysis of study data and early detection of subject compliance or technology issues.
>
> MyExperience is based on a three tier architecture of sensors, triggers and actions; triggers use sensor event data to conditionally launch actions. One novel aspect of MyExperience is that its behavior and user interface are specified via XML and a lightweight scripting language similar to the HTML/JavaScript paradigm on the web.
> 4 votes

# Answer
This is probably a bit old but there is a free iOS app called the PIEL Survey. It is in the App store. There is a web site which explains how to set up Experience Sampling surveys.
> 2 votes

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Tags: developmental-psychology, personality, software, internet, survey
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# Question
Title: Could neuroscientific knowledge and techiques be used to optimise peoples' education and learning?
Expanding upon this, I have two ideas behind this question - 1) that current knowledge of the brain and its workings (biochemically, biomechanically, physiologically etc) is in its infancy and that we are a long way from fully understanding the mechanisms of cognition and brain function......

and 2) There are people in this world that have amazing cognitive and mental capabilities and I believe they show off what the brain can achieve in terms of singular focussed abilities such as autistic savants.

These people are amazing at one or two abilities such as mental calculations, eidetic memory, polylingualism, prodigious musical ability etc and I realise these people have some sort of deficit or disability but I think it simply displays the potential that everyone could have if they had the right stuff (whatever this may be!).

Thinking of this potential when the time comes when we understand a whole lot more about the brain:

**Will it be possible to use neuroscientific knowledge to personalise each child's cognitive learning at each stage in their lives from say age one onwards through to school level to allow them to develop savant like capabilities, even if it isn't as impressive as actual savants?**

Thank you, sorry for the long winded question but my thinking is that the brain is capable of lots more and if we are today basing some of our education curriculum and structure on current scientific knowledge then surely in the future this could snowball for such sciences to fulfil our cognitive potential.

# Answer
There is an emerging trend in cognitive science called neuroeducation - the wikipedia page is of interest, especially the section "Neuroscience and education: A bridge too far" (I removed the question mark). https://en.wikipedia.org/wiki/Educational\_neuroscience

Another thought that came while reading your interesting question. It is about the desire to enhance the human mind, a desire that we find for example in the "transhumanism" movement (http://en.wikipedia.org/wiki/Transhumanism). If I understand the role of cognitive science as a science to describe how the mind works, I have a hard time thinking about it as a science that aim at modifying how the brain works. Cognitive science would not be a science anymore, but a technology.
> 4 votes

# Answer
There is one more way how to use neuroscience for better education and learning - the brain-based coaching by David Rock. This kind of applied neuroscience is part of some managerial courses.

The limits of neuroscience has been mentioned by Benedict XVI. in his encyklica Caritas in Veritate.
> 1 votes

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Tags: learning, cognitive-neuroscience
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# Question
Title: Is there any study on the effectiveness of taking notes in a lecture vs taking notes on written materials?
In many lectures I heard, I basically copied the lecture notes of the professor from the board into my notebook (I study mathematics). For me those lectures are comparable with going into the library, taking a textbook and making a handwritten copy from it.

The question I asked myself today: **Is there a study investigating what is more effective? Going to lectures where I copy the professor's lecture notes from the board or making a handwritten copy from the lecture notes by myself?**

(I assume here that the lecture notes are available, e.g. from the lecture's homepage)

On the one hand the professor might give additional comments in the lecture. On the other hand one can take the time he needs to understand a complicated paragraph when he works by himself and is not in the lecture. One also can skip easily understandable parts when he works by himself...

# Answer
> 9 votes
The primary value of taking notes by hand is not the record that you create, but that the act of taking notes causes your brain to engage more deeply with the material. You might never look at your notes again, but taking them has a strong positive effect on your ability to understand and remember the material that you are taking the notes about.

As such, you could potentially get similar value not by copying but by *summarizing* a text by hand. Taking notes in lecture gives at least one additional benefit: it provides a focused block of time in which distractions are less available to you. With a good lecturer, you get a second benefit: a lecturer is often much better than a text at directing your attention to the most important concepts in material.

# Answer
> 2 votes
A related question is whether taking notes by hand or by typing is more effective. Mueller & Oppenheimer (2014) found that taking notes by hand is more effective, and claim that this is because taking notes on a laptop results in shallow processing of the material.

I suspect that the most effective strategy in this case is to print out the slides beforehand, and use the margins to summarize and re-phrase things in your own words. Copying the slides verbatim when they are already available online is probably not a good use of your time.

# Answer
> 1 votes
I have studied in the two universities (have two diplomas). In the first university I studied, lots of attention was given for the lecture material, basically assuming that only facts, formulas and diagrams communicated during the lecture should be asked during the exam. Lecture notes contained exactly the needed material to prepare for the exam. Attending lectures and taking notes was vital.

In my second university, however, the emphasis was placed on learning to find and understand the needed material self-dependently. In addition, the lecture slides used to be published in the university website. Taking notes looked largely useless and even the need of attending all lectures looked questionable.

Hence depends on the general culture and style of the university, and you are out of luck if you misinterpret. I am not sure which approach is better, both can teach high level. The first approach gives more exactly knowledge. The second approach gives less for the same amount of student effort, but adds skills of the self-dependent work. Best would be to know the style before applying for studies.

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Tags: reference-request, learning
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# Question
Title: Number of exercises and the learning of some subject?
For example, I show to my students that X*Y=Z, so I ask for them to do some exercises, so in the future, they will always know that X*Y=Z.

Is there any known study relating the numbers of exercises needed to learn a subject?

And that relates the numbers of steps with the amount of practise?

Because we can see clearly that the sequency 1-3-8 is easier to remember than 1-3-8-6-9-8-7-5-5.

But the second sequency will need three more times of exercise to remember?

I think this may be useful in my studies, considering time a important factor.

If a do just some exercises, I just can half learn, and if I study much more than I need, I waste my time.

# Answer
> 1 votes
Learning is a very complex process, do not expect to find precise answers like “5 exercises are required to learn a new subject”. There are many factors that affect learning, just to name a few:

* Your existing knowledge.
* Your engagement with the subject.
* How you learn. Deep Vs shallow processing.
* The complexity of the subject.
* Your personal characteristics e.g. IQ.
* Your current state, how much tired you are etc.

With so many factors involved is impossible to give precise answers.

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Tags: mathematical-psychology, long-term-memory, mathematical-ability, short-term-memory
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# Question
Title: What evidence is there for a correlation between being tightly focused on a problem and only using one part of your brain?
I've seen people tightly focused on a problem, in a state of 'flow' and when you break out of it there seems to be a couple of seconds of confusion when they adjust to the circumstances at hand. It is almost as if there is only blood flow, or electrical activity to one part of the brain, and other parts of the brain are dormant.

Sometimes I see this with people who are doing computer programming and drinking coffee.

My question is: **What evidence is there for a correlation between being tightly focused on a problem and only using one part of your brain?**

# Answer
You may find some explanation from the research done for attention. In the most famous experiment done by Simon and Chabris 1999 (see video), participants inhibited irrelevant information that was not related to the task of counting passes.

When you are performing a task, you pay attention to what is relevant to the task, and inhibit irrelevant internal and external distractions. The more focused you are the more inhibitions occurs. The degree of focus you devote to a task depends from the difficulty of the task and the engagement you have for it.

Programming is a very highly demanding task and usually programmers are very passionate about it. So programming is a very focused task, thus everything unrelated to the task of programming is inhibited. When you do programming, you inhibit information like where you are, who else is in the room, hunger signals (I know programmer who forget to go to lunch) etc. When you are interrupted you need some time to re-activate all those things that have been inhibited.
> 2 votes

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Tags: problem-solving
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# Question
Title: Is there really a Shiny Object Syndrome?
The term "Shiny Object Syndrome" is used to describe the tendency to start new ideas without thinking them through, especially in business.

* Does this phrase represent an actual clinical diagnosis?
* Are there people who are more likely than others to be distracted by "shiny objects"?
* Can "shiny objects" cause further effects other than distraction?

# Answer
> 4 votes
**Does this phrase represent an actual clinical diagnosis?**

There is no such diagnosis in the DSM. Based on your definition (*the tendency to start new ideas without thinking them through*), it is probably correlated with psychological constructs such as impulsivity or deliberation. These can be measured using tests such as the Barratt Impulsivity Scale and Cognitive Reflection Test, respectively. Whether or not people who fall prey to "shiny object syndrome" in business are actually more impulsive or less deliberate is not clear.

**Are there people who are more likely than others to be distracted by "shiny objects"?**

Since "shiny object syndrome" hasn't been operationalized, it's impossible to say for sure. I think it's reasonable to believe there is individual variation here, either because some people are more cautious than others, or because they have learned from their mistakes.

**Can "shiny objects" cause further effects other than distraction?**

Sure, why not? By definition, it sounds like there would be a drop in efficiency or productivity, which can at least cause negative monetary outcomes.

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Tags: cognitive-psychology, attention
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# Question
Title: How does glial cell activity influence fMRI, EEG signals?
Glial cells comprise about 80% of the cells in the human brain. But physiological models of EEG and fMRI often relate only to neuronal activity.

How do glial cells affect large-scale imaging modalities?

Also, does glial activity artifact dye imaging and local field potentials?

Are microscale recordings more sensitive to artifacts due to glial activity than macroscale recordings?

# Answer
> 7 votes
I'm only going to attempt to answer a small part of your question: how does glial activation affect the blood oxygen level-dependent (BOLD) response measured by fMRI?

Schulz et al. (2012) were able to investigate the role of glial signaling on fMRI activity by simultaneously measuring neuronal responses with invasive optical imaging and fMRI. They found that glial activation prolonged the BOLD response, as shown in this figure:

Here's how they interpret this result:

> Although these glial responses did not initiate vessel dilations, they were associated with prolonged BOLD signals, suggesting a possible contribution to persistent vascular responses.

In other words: they hypothesize that the activity of the glial cells prolongs the dilation of the blood vessels, which is detected as a prolonged BOLD response.

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Tags: eeg, neuroimaging, fmri
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# Question
Title: Are some facial features more important than others in human facial recognition?
I'm often surprised by the human ability to correctly identify other individuals despite significant modifications due to ageing, hairstyle, injury etc. But, sometimes the addition of a beard and a hat can radically increase the identification error.

* Are all facial regions equally important when we try to recognise human faces?
* Do we focus more on some regions than others?

# Answer
> 3 votes
In a study by Pelphrey et al., 2002 the authors show that when people are asked to scan a face, they spend about 80% of the time looking at the eyes, about 10% on the nose region, and a few percents on the mouth (the remaining few percentages were spent on other non-core features such as ears, forehead etc). **Hence, the eyes by far draw the most attention and represent the most important feature when it comes to facial processing**.

A typical example of a visual scan by a human subject as examined by eye tracking is the following (taken from Pelphrey et al., 2002), which shows that the subject scanned the core features of the facial image (eyes, nose, mouth):

Nonetheless, the presence of a complete face makes recognition more efficient than when looking at incomplete faces (Tanaka & Farah, 1993)

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Tags: perception, vision, recognition
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# Question
Title: Short term memory and an effective learning strategy
What is the most efficient method learning multiple academic topics in parallel with each other. I propose, for a small number of different things (say 4), the best method is to cycle the topics, over the course of 4 days, i.e. topic 1,2,3,4,1... on days 1,2,3,4,5... respectively and working full days on each topic.

I am just wondering in terms of cognitive effectiveness is this the best strategy? Would changing up the topic every half day be more effective? I would tend to think that switching every half day could improve brains ability to work (reduced 'boredom') but maybe as the 2 topics would be inherently different it could hinder information retention for the first subject.

Does anyone know of any studies done which could relate to this or have any ideas themselves?

# Answer
By one of Tony Buzone's memory book, I would say the right way is to memorize a topic/data, then do a 10 minute break. After 10 minutes, repeat it again. Then, Repeat it the next day, the next month and then the next half a year. That should put the topic in your memory in the long term.

However, it also depends on what kind of data there is in each topic. If the data is too similar with each topic, it will be too hard to memorize all topics at once without being confused and without mixing up facts. Other factors that you didnt mention are the volume of material in each topic.

Lastly, order of topics is not important. You may reverse the order of the topics to devote your mental effort to the hardest topic as being hte first...
> 0 votes

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Tags: learning, memory
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# Question
Title: Is it possible to permanently improve long-term memory?
Many similar questions here ask either about working or short-term memory, or about various tricks and techniques to efficiently remember information. My question is, is it possible to improve the capability for remembering long-term itself? So that learning/memorizing something would take less time or repetition, and the acquired knowledge/information will be stored for longer and with less distortions.

The effect might not be permanent, but it should be prolonged and substantial. To illustrate my point, let's assume for argument's sake that learning poems has the effect of improving long-term memory. This would mean that, after regularly memorizing new poems for several weeks, i find that i'm able to memorize new poems spending less time, the poems retain remembered for longer. I'm also able to remember content of non-fiction and fiction texts better too, so that i can recall tricky facts and logical inferences, which before memorizing poems i tended to forget. So, is there a method to improve the general efficiency of your long-term memory? In other words, ability to retain more information for longer periods with less effort?

# Answer
This is what I do to store something in the long term memory.

1) Place it in the short term memory (those methods depend on the material).

* Use mnemonic memory techniques.
* Repeat the facts in different order.
* Relate the facts to something that you already know.
* Organize the facts in a logical order (order improves memory).
* Try to find semantic meaning the facts.
* Practice with active learning methods like writing and talking rather than with passive learning methods like listening and seeing.
* Make the learning experience engaging. Get involved with different activities that include using the material you have learnt. For example, teach it to others.
* Draw a vivid mind map of what you learnt.
* Jot down self questions on the material you had to remember.

2) Take a 10 minute break. Answer the test that you designed and the mind map that you drew in step 1, all from memory. Repeat step 1 for the facts which are the answers to the questions that you didn't answer correctly in step 1.

3) The day after. Do another repetition. Repeat what you didn't in step 2. This time mark the questions to your test that weren't answered correctly. During the month, every day, try to answer the questions that were marked as wrong by the previous day. So for example, if in day 3 you didn't answer right to question 4,6,8.. mark them and repeat only them on day 4. If you answered question question 4 and 8 correctly and 6 incorrectly, mark question 6 as wrong. Repeat the process every next day, until all the questions are right, then stop the process.

4) The next month from the day you started step 3. Repeat step 1-3. First, answer all the questions in your test, then make a general repetition. Design a new test..answer with the same technique described in step 3 to eliminate memory fading after the revision.

5) After half a year repeat step 4.

Just to add. I memorize dictionaries using this technique. If you have a lot of meaningless data to memories (dictionaries, encyclopedia, lexicons, fact books), you need a technique like mine, because most of the other techniques out there are too passive.

My technique also trains the memory better. It helps you to transfer memory from short term to long term (Especially the mnemonic techniques). The example that you bring relates to the idea of familiarity and semantic meaning. If you memorize English words, overtime it would be easier to memorize more English words than, let's say, french words. It does only increase long term memory for a specific topic, not for everything.

Other factors that help to improve your long term memory are amount of sleep, physical health and nutrition.

References:

* Tony Buzon. Memory books.
* Introduction to psychology book (A-level). Cognitive psychology chapter.
* Self-study skills gained through university.

Semantic memory might be the reason you find it easier to remember more and more poems as you continue reading them.

Some research: Semantic memory - http://www.sciencedirect.com/science/article/pii/S0022537173800568
> 3 votes

# Answer
I assume memories aren't static. And like any physical memory source, it has its own memorizing limits. So there are no permanent effects here. You can improve your memory capacity with different training methods, but effects decrease with time if you stop it, just like with muscles. There are also displacement and packing mechanisms that make you remember more/evaluate things faster, but instead you become "awkward" in other purviews.

**UPDATE:** Your example represent how memorizing is working - you did something once, brain make some new neuron connections and when you trying to do something similar brain use it and try to optimize it if possible. So to improve your brain possibilitis you just need some brain workouts. It doesn't really only about long-term memory. For clearer and longer memorizing you just need more new/optimized neuron connections.

Simple scheme looks like:

1. Find something new to you (Learning poems)
2. Repeat it until it gets easier (now you spent 1 days instead of 3)
3. Go to step 1 (start learn scenes)
> 1 votes

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Tags: learning, memory, long-term-memory
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# Question
Title: Grid cells : Between what is the correlation of autocorrelogram measured?
In their seminal paper Hafting, Torkel, et al. "*Microstructure of a spatial map in the entorhinal cortex*." Nature 436.7052 (2005): 801-806. the Mosers have discovered the grid cells.

To show the existence of these cells, they have counted spikes as a function of location, plotted (figure 1.b) a rate map and finally the most known figures of autocorrelogram which beautifully visualize the grid response pattern of these cells.

Auto-correlation is measured between a signal and itself (e.g. when one of the signals is shifted in time). **My question is**, what is the signal from which the autoelectrogram is calculated and what are the different states of that signal, between which the correlation is calculated (explanation is given at the paper's methods section, but it still didn't help me much).

# Answer
> 3 votes
Autocorrelation is calculated between the spikes-histogram and itself.

The experiment is carried out while the activity of a specific neuron is recorded.

1. **Histogram** \- An animal runs in a circular arena which we divide into multiple squared bins, whenever the cell fires (i.e. generate an action potential) 1 counter is added to the location (the bin) in which the animal is currently located.
2. **Autocorrelation** \- Two instances of the spikes histogram are observed such that one is "placed on-top of the other" and the correlation between the two instances is calculated.

* When ***the two instances are perfectly aligned***, their autocorrelation is 1 (they perfectly match).
    * Now we start ***moving one of the instances***. The match between the two instances is not perfect (the autocorrelation is smaller than 1) but because there are peaks (at the spikes-histogram) all across the arena, if we shift one of the instances such that it would be ***"on top" of another peak*** (e.g. each peak is aligned with the peak directly to its right) the autocorrelation would, once again, equal 1.
    * ***(τX,τY)*** \- The shift of one of the instances is carried out for ***every value of x and y*** of the arena (i.e. for every ***phase***) and the value of autocorrelation for each (τX,τY) shift of the first instance relative to the stationary second instance is plotted - this is what the autocorrelation figure shows.
3. **What should we learn from the autocorrelation figure** \- That the cell response is indeed represented by ***a grid***. The figure exemplifies that when the spikes histogram is shifted in a single full period (i.e. to the next peak) it fully matches itself, so the grid pattern indeed characterize similarly the whole arena (***tessellating*** it).

# Answer
> 2 votes
*The recorded signal* are **spike responses (action potentials)** (p.2 Method section), the *different states* are **spike rates** (p.4), and the calculated *correlation* is determined between **spike rates and maze coordinates** (p.5).

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Tags: neuroscience, electrophysiology
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# Question
Title: Why do some people stutter only when they are nervous?
**Background:** I don't stutter at least not always. For example, if I be reading out a article to myself, It is sure that I will not stutter even that I am reading it out loud. The times when I do stutter is say when I am doing a presentation in class! or just saying something to my mother.The time always came up without warning. I will not know If I am gonna be stuttering reading a certain word until I actually reach it. It really creates a problem for me, and I can't find the reason for it..

**Question:**

* Why do people stutter when they are nervous?

# Answer
Interesting question!

Assuming you are talking about stuttering, as occurs in about 1% of the population (Sommer et al., 2003), as opposed to non-pathological stammering during stressful situations that many more people experience, my answer is as follows:

Stress and speech disruption in stutterers are undoubtedly related (e.g., Craig, 1999). In fact, they may be causally related, as stress can provoke or aggravate stuttering, which in turn may cause more stress to the stutterer due to feelings of shame or loss of control. This in turn may induce more stuttering and may thus lead to a downward spiral, or vicious circle (Schwartz, The Stuttering Child) that may grossly disrupt speech.

The underlying physiological basis of ***why*** stress provokes stuttering has been addressed by Weber & Smith, (1990). It shows that speaking increases autonomic activity (elevated blood flow, increased heart rate, sweating) and that this sympathetic arousal was correlated with increased stuttering behaviors in stutterers. Interestingly, the sympathetic arousal of stutterers was found not to be outside the range of controls. The authors bring up several hypotheses as to why sympathetic activity may deteriorate speech fluency in stutterers:

* Increased autonomic activity has been associated with **irregular breathing**, which may affect speaking;
* Release of the **stress hormone adrenalin** may induce **muscle tremor** and **spasms** that can affect speech production;
* Sympathetic regulation of **afferent control of the sensitivity of sensory receptors** (muscle spindles and mechanoreceptors) in the **oralmotor, laryngeal and respiratory system** may affect speech motor processes;
* The **gain of reflex arches** (feedback) involved in the **musculature engaged in speech** may be modulated such that speech fluency is negatively impacted.

These processes may aggravate the underlying pathology of stutterers (Büchel & Sommer) and hence lead to more pronounced stuttering under stress.

<sup>*PS: Being a stutterer myself since early childhood, I support the behavioral consequences of stress mentioned in above studies by anecdotal experience :)*</sup>

**References**
\- Buchel & Sommer, *PLoS Biol* 2004; **2**(2): e46
\- Craig, *J Speech Hear Disorders* 1990; **55**: 290-4
\- Schwartz, The Stuttering Child, Coping With Stuttering
\- Sommer et al., *Movement Disorders* 2003; **18**(7): 826\*30
\- Weber & Smith, *J Speech Hear Res* 1990;**33**(4): 690-706
> 4 votes

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Tags: neuroscience, abnormal-psychology
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# Question
Title: How does the brain know whether or not it comprehends a novel concept?
There seem to be at least two kinds of confusion regarding novel concepts.

In one, the brain simply can't form an abstract model from whatever information is being presented. It's where you can't "wrap your head around" something.

In another, the brain perceives a cognitive dissonance, where something doesn't "add up", but further information provides a unifying model that can explain everything being presented.

They seem to be related.

**The brain is somehow able to evaluate the fidelity of an abstract model that it's trying to construct. How does this happen?**

# Answer
> 5 votes
Interesting question! A related phenomenon called the illusion of explanatory depth (IOED) suggests that the human cognitive system has a systematic weakness in this kind of evaluation--I believe the classic example is asking people if they know how a helicopter works (most people say yes), and then asking them to explain how a helicopter works (very few people even get as far as mentioning airfoils or lift).

Although the mechanism behind the illusion of explanatory depth (and thus the mechanism behind evaluation of incomprehension in general) is understudied, a 2010 review examined six studies and drew a few conclusions:

* IOEDs have been found in natural, mechanical, and social-psychological domains.
* People who adopt a concrete construal style (as opposed to an abstract style), either naturally or from prompting, diminish the scope of their IOED.

Missing the trees for the forest: A construal level account of the illusion of explanatory depth. Alter, Adam L.; Oppenheimer, Daniel M.; Zemla, Jeffrey C. Journal of Personality and Social Psychology, Vol 99(3), Sep 2010, 436-451. http://dx.doi.org/10.1037/a0020218

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Tags: perception, cognitive-neuroscience, cognitive-modeling, reading, artificial-intelligence
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# Question
Title: Consistency Theory - Why do we go back on promises
I'm fairly new to the field of social psychology so forgive me if this sounds like a naive question.

I just read about the consistency principle - "Once we make a choice or take a stand, we will encounter personal and interpersonal pressures to behave consistently with that commitment. Those pressures will cause us to respond in ways that justify our earlier decision."

I have the question - exactly what kind of decision/commitment are we talking about? As in, how do we reliably identify a situation in which a person has made a decision/commitment such that he will now behave as per the consistency principle?

If the consistency principle is really so pervasive, then why do people often back out of promises? There are tons of situations when people don't honor their "commitment" towards other people (for example not showing up for some social event, or not showing up for a date, etc.)

# Answer
There's no reason that consistency and promise-breaking can't both be pervasive. In the first place, if 20% of the population always broke promises and another 20% always obeyed the consistency principle then we would still call it pervasive and we still have 60% of the population.

But an additional complication is that no person always breaks promises or always obeys consistency and most people do both at some point. We can imagine a scenario in which a politician could simultaneously break a promise (to a rival political force) and obey consistency principle (keeping the promise would have betrayed his base). So the two aren't really contradictory since consistency principle doesn't require one to be consistent about everything always.
> 1 votes

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Tags: social-psychology, decision-making, commitment
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# Question
Title: What is the effect of viewing pornography on children?
It is generally accepted that porn shouldn't be seen by children, and we even sometimes punish parents who fail to stop their children from finding porn.

How much are these laws based in science? Can a simple image cause real injury beyond mere disgust? Have there been any studies that track lives of people who were exposed to porn or other disturbing imagery as children or adolescents?

Note that I have also posted this question on parenting.SE.

# Answer
Pornography laws are a relic of the Victorian era, and not based on any science.

Research that can conclusively determine the effect of pornography on children is hard to come by due to the resultant ethical environment. Most research depends on self-reports: Surveys ask adolescents how much pornography they have been exposed to, and attempt to correlate this with other variables such as personal attitudes about sex. Such surveys are subject to a variety of memory and other biases affecting accuracy, but more importantly, correlations fail to establish cause and effect - that is, it is equally likely that pornography consumption affects attitudes as it is that pre-existing attitudes affect pornography consumption.

Nonetheless, a number of reviews of current literature on adolescents conclude that there is an association between consumption of pornography and certain negative attitudes about sex, and promiscuous and/or risky sexual behaviour. The reviews acknowledge that the data contains much contradictory evidence however, as well as failing to establish cause and effect.

UK Children's Commissioner's report (2013): "Basically... Porn is everywhere"

Owens et al (2012): "The Impact of Internet Pornography on Adolescents"

In contrast, a paper by Kendall (2006) found a correlation between pornography accessibility and rape for 15-19 year old adolescents - but in the opposite direction, that could be interpreted to mean that access to pornography reduces rape crime in this demographic. A meta-analysis by Wright, Tokunaga, & Kraus (2016) found no difference between adults and adolescents in association between pornography consumption and sexual aggression.

Research on pre-adolescents is even more scant. A more conclusive effect is seen between exposure to depictions of violence and negative effects on attitudes and behaviour, though these may be short-lived. A landmark study from the 1960's (no longer ethical to replicate) demonstrated that children do role model from violent media. The reviews listed above extend this finding to attitudes and behaviours of adolescents exposed to pornography depicting violence. Evidence linking this to criminal offences in adulthood is still controversial however.

In adults, studies across multiple countries (eg, Diamond, Jozifkova, & Weiss, 2010) have documented significant declines in physical sex offenses as accessibility of pornography increases, again suggesting the possibility that pornography provides a substitute for sex crimes.
> 16 votes

# Answer
So I cross posted this question to Parenting Stack Exchange, and here's what I got.

In short, people who have viewed porn as adolescents have more sex and greater risk of sexually transmitted disease. And some of the kids who have stumbled upon porn on the Internet became averse to the Internet and some others developed unwanted recurring thoughts about the material they had seen.
> -5 votes

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Tags: abnormal-psychology, developmental-psychology, sexuality, parenting
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# Question
Title: Do lonely people get addicted more easily than social counterparts?
The so-called "Rat Park" study conducted in the late 1970s indicated that lonely rats get drug addicted more easily than social ones.

Does anyone know if there are more recent studies about the topic? About drug addictions or other addictions?

**Reference**

Alexander, B. K., Coambs, R. B., & Hadaway, P. F. (1978). The effect of housing and gender on morphine self-administration in rats. *Psychopharmacology*, *58*(2), 175-179. doi:10.1007/BF00426903

# Answer
> 3 votes
First of all, the rat experience is not so relevant to a great extent to the question. Animals can't reason (they can't have their own belief system and plan for the future).

However, there is some similarity with rats and humans. Rats are social creatures too. It could be that loneliness causes bad feelings and a distraction technique could be the drugs to which they got addicted. That might explain why the rats got addicted to the drugs. For animals is all about stimuli, they don't have a belief system. I think that even if a social rat saw the drug and tried it once and a few more times it would get addicted. Same for people, drugs can be as part of a recreational/social activity.

Another comment, is that loneliness is basically the feeling of stress (because it is an inner feeling of unhappiness and a mix of anxiety, all which brings the person to rationalize that he is lonely). I would argue that since loneliness creates stress, to relief stress the individual turns to an avoidant stress coping strategy which is drugs consumption.

My account is one, there are more accounts of that relationship that other people add. But I struggle to bring any other relationships that will not be seen as being too much based correlation.

Also note that there are different mentality behind different psychology. Addiction of gambling is not the same as being addicted of drugs. In the former, the addict is addicted to win and in the latter the addict is addicted to the drug that kills the mental/physiological pain s/he has.

Some research: http://www.sciencedirect.com/science/article/pii/S0924977X03001779

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Tags: social-psychology, abnormal-psychology, addiction
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# Question
Title: Removing ocular artifacts from EEG signals
I have read the following paper , which is try to remove EOG artifacts from EEG signal , the authors give the following figure .

The authors claim that components 1 and 2 represent electro-oculographic (EOG) artifacts. This is because its scalp map refers to locations very near to eye. My first question is **how we map an ICA component to a certain location on scalp map**. Secondly, how do we know **a component lies on the front of the head**, and not on another location, for example the center?

# Answer
In short: we know that eye-blinks are reflected frontally in the EEG data and we use that knowledge to identify which components reflect for example eye-blinks. It would not make sense to identify a component related to eye-blinks on the back of the head - there would be something wrong with your data.

What ICA does is (data driven) estimate a number of statistically independent components (if you have 64 channels you get 64 components) based on your data. The input data is usually in the form of channels X timepoints X trials.

Eventually the output of ICA gives you, for each component, a weight for each channel which you can use to create the component scalp map. Together, the component scalp maps, the time course of the components, and frequency information of the component provide supplementary information that you can use to identify artifacts such as (but not limited to) eye-blinks, horizontal eye movements and heart beat.

In the above figure component 14 and 15 do not seem to be eye artifacts. (1) they are very focal, which is probably related to noise specific to that channel. (2) They look to be completely uncorrelated with the eye blinks in the original signal.
> 12 votes

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Tags: eeg
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# Question
Title: How is the biological accuracy of ANNs typically measured?
I am referring to the computational neuroscience side of neural network research that focuses on biological accuracy. I've read references to improving biological realism (using say spiking neurons or binding neurons of various types) by emulating known properties of real neurons (action potentials and what not). However, I haven't been able to find any detail on how the effectiveness of such attempts is measured empirically.

For example, cultured neuronal networks (such as a neurochip) could be used as a benchmark: Create an ANN and a BNN with the same number and arrangement of neurons, give them the same inputs, and compare the results... Has anything like that been attempted? How is the biological accuracy of ANNs typically measured?

# Answer
> 7 votes
One way the biological plausibility of an artificial neural network could be assessed is to look at how much a neural network abstracts away from the behavior of real neurons.

For instance, it is common in psychology and machine learning to use a sigmoidal activation function to determine the output of a node. If biological plausibility is a concern, one might prefer to use the Hodgkin-Huxley model. (See also: other neuronal models).

To many practitioners, biological plausibility is not a primary concern. In most ANNs, each node is not really believed to be implemented by a single neuron in the brain, and thus using a more realistic activation function does not necessarily make the network more biologically realistic.

Personally, I don't think looking at the behavioral accuracy of a biological neural network (compared to an artificial neural network) says anything about the network's biological plausibility. Using more abstractions might produce more similar behavior due to less overfitting. Another concern is that the ANN could produce the same behavior as a BNN even if the actual computations involved are quite different.

# Answer
> 6 votes
Due to my newness to the field, I can only talk about comparisons of biological plausibility when discussing the Neural Engineering Framework (NEF) and functional modeling. What is missing from this answer is a purely bottom-up modelling perspective in the same vein as the Blue-Brain project, but I'll leave that to another user.

One of the claims driving the push towards cognitive modelers using the NEF is the fact that it is more biologically plausible than back-prop ANNs. What is typically discussed is the neural mechanism for encoding, decoding and learning of the NEF has more scientific evidence claiming their plausibility than back-prop ANNs.

From a more systematic biologically plausible perspective, the NEF is also used to build neural networks that use Semantic Pointer Architecture, which is also claimed to be more biologically plausible for a number of reasons. First of all, the number of neurons required for most models in significantly less than other proposed models (see Eric Crawford's work on knowledge representation). Secondly, modifications to the network mimicking the effects of neurological disorders can be shown to have the same effect of those disorders (see Dan Rasmussen's work on general intelligence).

In terms of the bottom up perspective, the NEF could help here as well. The NEF is neuron-model agnostic, so it can be used with any of the neuron models you mentioned in the question. Hypothetically, it could be possible to create a similar network to one grown on a Neurochip and compare the various inputs and outputs as you suggested, but I've never heard of such a study being done.

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Tags: computational-modeling, neural-network
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title: What kind of memory it is?

text:
# Question
Title: What kind of memory it is?
I was reading about various memory techniques : mnemonics, memory space, peg system, space repetition etc . They are used when I have to memorize something by myself for longer duration.

There are many other memories which are in my mind but I dint memorize them by myself. They are automatically stored. Like : my travel experience, some childhood activity etc . Some of them are faded some are still very clear. I can visualize them clearly.

But there are some memories, I cant visualize them. But I still remember. For example : if I try to visualize or write position of 'G' key on laptop keyboard, I can't. But still when I type, my fingers know its exact position. Similarly, if someone asks me to write my national anthem, I can't. But I can sing it without any mistake. Why does it happen so. Can't I remember everything in this way instead of any other memory technique? The advantage of this is quick recall.

# Answer
> 4 votes
The travel experience etc, are episodic memories. The duration of these memories mostly depend on emotion and novelty.

The typing and singing, are procedural memories. They are formed with practice. Repetition and consistency are the two most important factors for this type of memory. We do not have any conscious access to procedural memory, we simply perform what we know.

The PIN memory can be explained with cued recall. The image of the post office is associated with the PIN, so whenever you imagine the post office the PIN number is also activated.

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Tags: memory
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title: What are presynaptic puncta?

text:
# Question
Title: What are presynaptic puncta?
What are presynaptic puncta? And what makes them different from presynaptic terminals?

I encountered the term *puncta* in the following article:

Molofsky AV, Kelley KW, Tsai HH, Redmond SA, Chang SM, Madireddy L, Chan JR, Baranzini SE, Ullian EM, Rowitch DH (2014) Astrocyte-encoded positional cues maintain sensorimotor circuit integrity. *Nature* **509**: 189-194.

# Answer
> 6 votes
In the article you provided (Molofsky et al., 2014) the authors refer back to (Arber, 2012) and surprisingly, the term *puncta* is not used in the latter. So that's pretty much a dead end.

I found another article (Ippolito & Eroglu, 2010) in which the authors do explicitly clarify their use of the word *puncta*. In this article, *puncta* is a term used in the Puncta Analyzer plugin for *ImageJ*. Image J is freeware to analyze histological preparations and features many options for histological analyses. ImageJ was also used in the article you originally referred to (Molofsky et al., 2014). The plugin specifically analyzes co-localizing spots identified in a preparation. Co-localization can be studied by, e.g., labeling of two different antigens (double-labeling). Co-localizing fluorescent markers in a preparation often indicate that the two proteins are localized very closely in the cell, and are probably involved in the same mechanism.

To extrapolate the information back to your question we could formulate a hypothetical histological example involving neurotransmission. **Presynaptic puncta** could then be formed when (e.g. red) fluorescent antibodies for an autoreceptor and another (e.g. green) fluoresecent antibody targeting a modulator of the autoreceptor would colocalize on a presynaptic membrane of a certain synapse. The green and red would appear as a purple spot in the overlaid image, and the plugin would identify this as *puncta*, in turn showing that the two are very close in the synapse on the presynaptic membrane.

In all, given the heterogeneity of the articles reviewed and their use of the term *puncta*, I think '*puncta*' can be loosely defined as: **"(immuno-)histological locations defined by computer algorithms using ImageJ and related plugins"**.

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Tags: neuroscience, terminology, neurophysiology, neuroanatomy
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# Question
Title: How to transform data to a frequency spectrum?
Recently, I studied a paper called "What Does Your Chair Know About Your Stress Level?

It can be download at the link below.

> http://www.barnrich.ch/wiki/data/media/pub/2010\_what\_does\_your\_chair\_know\_about\_your\_stress\_level.pdf

at page 210, Fig.5 (picture 5) mentioned that

> Spectra of the norm of the CoP vector during the experiment (stages 3–7) for the same subject used in Fig. 4.

How did they do to transform Fig.4 to Fig.5? And what do x-axis and y-axis mean in Fig.5?

Fig4

Fig5

# Answer
In the cited paper their methodology is explained in the Materials and Methods section on p.209, where it says:

> Fig. 4 shows the norm of the CoP during the experiment \[...\] which are represented by spikes in the norm of the CoP \[...\] In order to characterize the movement properties of the CoP, we have computed the corresponding spectra over the experiment stages \[...\]. Fig. 5 shows the spectra of the norm of the CoP \[...\].

Spectra, or more appropriately called **frequency spectra** or spectrograms, are typically generated by **Fast Fourier Transformation** (FFT). FFT essentially decomposes a signal into a collection of sine waves. The **x-axis** of a spectrogram (like Fig. 5 in the article) represents the **frequency** of each sine wave, the **y-axis** the magnitude (amplitude or more aptly the '**power**') of each sine wave in the frequency spectrum.
> 6 votes

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Tags: experimental-psychology, task-analysis
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# Question
Title: What are the possible causes of sometimes using incorrect word ordering when speaking?
A friend sometimes speaks with incorrect word ordering. However, he writes English at a professional level. How could this be? His vocabulary is fine, just the word ordering is weird sometimes when he speaks. I always understand his meaning. He seems to not know that he is using incorrect word ordering. He speaks very slowly. His reading and listening appear fine.

# Answer
Have you noticed your own word ordering as well as your word decisions?

Better: *Sometimes, a friend says his words jumbled, seemingly out of place. Though I understand him, always, he seems to be unaware of how he speaks. As well, she speaks slowly. Yet, this friend writes well. Also, he seems to listen well. What could cause his problem?*

Look up *Anosognosia* and *Aphasia*.
> 1 votes

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Tags: language
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# Question
Title: What does speaking in third person denote?
Is speaking (or preferring to speak, even if not actually doing it) about oneself in third person a symptom of any specific mental condition?

I can remember a person in an IRC role playing chat room who preferred to speak this way. But apart from this specific case, I am also asking in a broader context.

# Answer
Speaking about oneself in the third person is known as illeism.

It is not a symptom of any mental condition listed in the DSM. As Wikipedia notes, it is sometimes used in speech and literature for stylistic reasons.
> 3 votes

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Tags: abnormal-psychology
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# Question
Title: What do you call the inability to see alternative solutions to a problem?
Once I "learned" for a condition in which you have a specific solution of a problem, but you are only thinking of it and do not realize there are other / probably more appropriate / solutions. Something like.. being stuck to an attempt of a solution.

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So there was a name for it. But google results for tokens such as "Problem Solving Disease" lead me to nothing related.

# Answer
> 6 votes
This is called the Einstellung effect:

> ...Einstellung refers to a person's predisposition to solve a given problem in a specific manner even though "better" or more appropriate methods of solving the problem exist

It is related to the idea of functional fixedness:

> Functional fixedness is a cognitive bias that limits a person to using an object only in the way it is traditionally used. \`

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Tags: cognitive-psychology, social-psychology, conditioning
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# Question
Title: Is it really impossible for a hypnotist to make a participant do something against their will?
Is there any evidence of a hypnotist making someone do something against their will while in a hypnotic state?

I know there are many sites by practicioners that state it is impossible, but they have a vested interest in making their potential patients feel safe.

# Answer
> 10 votes
This question cannot be answered empirically.

> Thus, a refusal to carry out antisocial actions can be ascribed to insufficient depth of hypnosis (or inadequate hypnotic technique), while the behavior of S\[ubject\]s who comply can be explained by asserting that the action merely represents what they would have done anyway. (Orne, 1972)

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Sources:

* Orne, M. T. (1972). Can a hypnotized subject be compelled to carry out otherwise unacceptable behavior? A discussion. *International Journal of Clinical and Experimental Hypnosis, 20*(2), 101-117.

# Answer
> 2 votes
Just to add to @what's great answer (that this is not a testable question), a while ago I watched a Derren Brown episode where he successfully hypnotizes someone to assassinate a co-conspirator.

This was supposedly to test the Manchurian Candidate hypothesis (and incorporating a polka-dot dress) - a conspiracy theory that the CIA used hypnosis to train unsuspecting victims to assassinate on command.

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Tags: hypnosis
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# Question
Title: How is the signal-to-noise ratio of an event-related-potential measured?
I often encounter publications where the authors try to "increase the SNR (signal-to-noise ratio) of electroencephalogram (EEG) signals". Some define a numeric value of SNR of EEG signals, but I am confused as to the exact **definition of the SNR** and **how it can be measured** for ERPs?

Previously, I have calculated the SNR using a model of noise, for example a Gaussian model. I have also encountered SNR calculations based on a ratio between the mean and the standard deviation of a signal, but both of these approaches seem to be impractical. When I process the EEG signal, I would like to emphasize how the ERP changes in the EEG signal. All of this is strongly related with variance. If the variance approaches to zero, then theory tells me that SNR goes to infinity (a really good signal), but the signal that I will have is useless.

Is there a better way to measure the SNR then I have mentioned?

# Answer
> 7 votes
Based on your comments I interpret your question as:

***"(1) What is the definition of the signal-to-noise-ratio (SNR) and (2) how do I determine the SNR for event-related potential (ERP) amplitudes in an EEG signal?".***

(1) **Signal-to-noise-ratio (SNR)** is a term often encountered in electrophysiology (e.g. EEG) and signal processing and can be loosely defined as the ratio of the relevant signal divided by the noise level. The signal in this example is the ERP amplitude, while the noise is the remaining background activity in the EEG that distorts the ERP (unwanted noise). Noise includes hardware noise, movement artifacts by the subjects, random synchronized brain activity and so on. So SNR = signal/noise.

(2) In case of ERP amplitude being the signal you are after, than the noise is the amplitude of the background EEG (SNRERP\_amplitude = ERPamplitude / NOISEamplitude). The ERP amplitude can be defined by determining peak amplitude (e.g. relative to baseline). A straightforward (and widely accepted method) to characterize noise amplitude is determining the standard deviation (SD) of the entire EEG epoch (e.g., 500 ms) in which the ERP was recorded (Hu et al., 2010). Then, the **SNR** becomes ERPamplitude / SDEEGepoch.

PS: your comment

> If the variance approaches to zero, then theory tells me that SNR goes to infinity (a really good signal), but the signal that I will have is useless.

is incorrect. The signal is always part of the EEG epoch. Assuming there is a measurable ERP on a flatline background EEG (amplitude=0), than the signal will be the only thing that adds to the noise component. This is counter intuitive, but note that when noise amplitude is defined as, e.g., the SD, than this SD will be very small as it is determined across the entire EEG epoch. Hence, the peak-amplitude of the ERP will be much larger than the SD. In this ideal ERP recording the SNR will be large, but it will *never become infinitely large*.

**Reference**
**-** Hu *et al*., *NeuroImage* (2010); **50**(1): 99-111

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Tags: methodology, eeg, event-related-potential
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# Question
Title: Where can I find a database, preferably OWL-based, that contains structured information about everyday objects?
I'd like a database that has information like that fact that a table is

* made of wood
* is composed of a top and legs
* is used for eating food off
* etc

And I'd like this information to be semantically structured, rather than in natural language. By that, I mean that I would like there to be an ontology defined with terms like isMadeOf, hasColorOf, isUsedFor etc, so that it becomes easy to select all white objects, or all objects made of wood etc.

Is there such a publicly available database or something along those lines? I've found ontologies such as OWL that, if I understand correctly, define things like ways of noting that two objects are symmetrical etc, but I haven't so far found any decent size databases that contain actual knowledge.

Many thanks for your help!

# Answer
Cyc is similar to what you are looking for. It is a database of general knowledge and is organized semantically. It is free to use for research purposes.
> 3 votes

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Tags: artificial-intelligence
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# Question
Title: Can you make yourself like/hate something when you learned to hate/like it during early life?
Suppose that someone develops liking (or even obsessing with) something since very early life, e.g watching football from age 5 to age 25. Is it possible to consciously make oneself hate it when one is older?

Can the converse happen also? Is it possible to hate something at a young age and then consciously make oneself like it when older?

If this "brain rewiring" can happen, what are the methods to achieve it? Is there any research on this subject?

# Answer
> 1 votes
I think most of "loving" and "hating" happens on unconscious level or conscious but automatic level. Aaron T. Beck noticed that thoughts were not as unconscious as Freud had previously theorized and called them "automatic thoughts". I don't see any reason for someone to start hating football but also you can get bored for watching it for 20 years.
But you have techniques, exercises and therapies that can help you love yourself, start hate smoking or stop overeating for example.

Cognitive behavioral therapy (CBT) can be used for solving current problems and modifying dysfunctional (inaccurate and/or unhelpful) thinking and behavior.

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Tags: learning
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# Question
Title: Are there any theories suggesting mindfulness is the opposite mental state to self-regulation?
Meditation practice focuses on emotional acceptance (Teper & Inzlicht, 2013), and self-regulation is related to emotional control (Braumeister, 2003). Could someone provide me with pointers to some models/theories or related literature (if there is any) contrasting these two mental states?

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### References

Teper, R., & Inzlicht, M. (2013). Meditation, mindfulness and executive control: the importance of emotional acceptance and brain-based performance monitoring. *Social cognitive and affective neuroscience*, 8(1), 85-92.

Baumeister, R. F. (2003). Ego depletion and self‐regulation failure: A resource model of self‐control. *Alcoholism: Clinical and Experimental Research*, 27(2), 281-284.

# Answer
I don't think there's any evidence suggesting that mindfulness or meditation are the opposite of self-regulation. In arguing why, it'll be useful to define terms.

### Meditation and mindfulness

First off, meditation and mindfulness are not the same thing. Meditation generally refers to a family of practices for investigating or inducing different states of consciousness. For example, "loving-kindness" meditation requires focusing your attention on the feelings of love and closeness you have towards someone in your life (and has been studied by Fredrickson, et al., 2008). There are many forms of meditation, and so the link between meditation and self-regulation could vary based on the type of meditation one is thinking of. The type of meditation you seem to be thinking of is mindfulness. So let's talk about what mindfulness is.

Mindfulness is generally thought to have two components: 1) a regulation of attention to conscious experience of the present moment and 2) non-judgement or non-evaluation of that experience. (a definition I paraphrased from Greenberg et al. (2012); note that they discuss alternative conceptualizations as well). So, when you catch yourself in yoga class, daydreaming about what you're going to make for dinner tomorrow, and then stressing about whether or not your dinner guests will like it, you are failing both criteria for mindfulness. Conversely, if you find yourself in a yoga class, aware of how each of the positions makes your body feel, and you simply notice (rather than judge or react to) these feelings, then you're being mindful.

### Emotional self-regulation

Your question relates to the link (if any) between mindfulness and emotional self-regulation in particular. So, let's clarify what emotional self-regulation is.

Emotional self-regulation is the ability to override one's undesirable emotional impulses into more desirable ones. For instance, you may find your mother-in-law insanely irritating. When she comes around, you have a strong impulse to yell and shout about how obnoxious she is. However, this action doesn't really jive with your goal of maintaining a peaceful, pleasant relationship with your spouse. So, if you manage to suppress the urge to shout at your mother-in-law, and replace it with a more acceptable tight-lipped grin, you've successfully self-regulated (much better than I probably could).

### Link between the two

It seems that mindfulness ought to increase one's ability to self-regulate in this way. Specifically, mindfulness should help one A) identify the emotional impulse as it shows up by increasing attention to one's present moment and B) neutralize the intensity of the emotional impulse by reducing the extent to which one justifies or identifies with it.

If you're viewing emotional impulses mindfully (noticing them as they show up, and not judging or evaluating them), then you're simply treating them as perturbations of conscious experience. In other words, they're just another change in your experience, as if someone had changed the color of the lights in the room. Seeing emotional impulses as mere changes in conscious experience creates some mental space between you and them. All of a sudden you don't feel so identified with your emotional experience (any more than you feel identified with the color of the light in the room).

The literature offers some support for these arguments. Brown & Ryan (2003) find a positive correlation between trait mindfulness (one's general propensity for mindfulness) and several constructs related to emotional self-regulation. It's correlational work, so we're not sure which of these is causing the other. Nevertheless, the signs of the correlations suggest the concepts are, at the very least, not opposites. More mindfulness tends to be associated with more emotional self-regulation

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## References

Brown, K. W., & Ryan, R. M. (2003). The benefits of being present: mindfulness and its role in psychological well-being. *Journal of Personality and Social Psychology*, 84(4): 822. http://selfdeterminationtheory.org/SDT/documents/2003\_BrownRyan.pdf

Fredrickson, B. L., Cohn, M. A., Coffey, K. A., Pek, J., & Finkel, S. M. (2008). Open hearts build lives: positive emotions, induced through loving-kindness meditation, build consequential personal resources. *Journal of Personality and Social Psychology*, 95(5): 1045. http://psycnet.apa.org/psycinfo/2008-14857-004

Greenberg, J., Reiner, K., & Meiran, N. (2012). “Mind the trap”: mindfulness practice reduces cognitive rigidity. *PLoS One*, 7(5): e36206.
> 8 votes

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Tags: emotion, reference-request, cognitive-modeling, meditation, self-discipline
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title: Visual acuity and offset stimuli

text:
# Question
Title: Visual acuity and offset stimuli
I'm currently setting up and experiment that utilises a visual search task that contains a circular array of target letters and a distractor that falls outside the circle.

Obviously the further away from the fovea the distractor moves the more difficult it is to see.

Can anyone point me to some literature as to how one would go about scaling the size of the distractor relative to the target letters to maintain comparable levels of acuity.

Most of the literature I've read doing similar experiments make the distractor bigger for this very reason. |But I'm having a hard time figuring how how one goes about deciding how much bigger the distractor should be.

# Answer
> 6 votes
Visual acuity is highest in the foveal region, namely around 1/60 of a degree, **or 1 minute of arc (1 MAR)**. At about **30 degrees** of eccentricity, visual acuity is reduced to anywhere between **1.5 and 10 MAR** when determined by a shape recognition task, as shown in Fig. 1 taken from Lie, 1980:

A later study (Anderson et al., 1991) shows the following picture:

This figure shows that chromatic (color) visual acuity is about 60 cycles/degree in the fovea (i.e., 1 MAR) and approximately 0.4 cycles/degree at 30 degrees eccentricity temporally, which means a **reduction in acuity of 150x**. At 30 degrees eccentricity to the nasal side acuity drops to 1 cycle per degree, which means a **60x reduction**. Under achromatic (black-and-white) conditions it drops about **60x temporally** and **30x nasally** at 50 degrees eccentricity. These tests were done using colored (red/green) and black-white grating-visual acuity tasks.

The Lie, 1980 study mentions several references and the Anderson, 1991 study is definitely worth checking out as well.

To get back to your scaling question: it is difficult to directly translate these findings into scaling factors for your stimuli as you make no mention of their approximate size, or their eccentricities. What the figures do show, however, is that people may not be able to see much detail in their periphery and that **acuity may drop as much as 150x** at an eccentricity of 30 degrees. It also shows that **black-and-white stimuli may be better visible** in the far periphery and also, quite interestingly, that **acuities deteriorate at a faster rate** with eccentricity **in the temporal retina**.

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Tags: neuroscience, experimental-psychology, vision
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# Question
Title: Does a condition exist that resembles autism, but featuring much instead of little empathy?
I recently read a book by an autistic author who relates his experiences in professional life in IT. (He was diagnosed only in mid adulthood.) Colleagues see him as highly intelligent but also stubborn and egocentric. He explains that he cannot read people's faces and therefore misses out on the non-verbal part of human communication, which is 80%. Because he cannot remember faces, he often cannot greet acquaintances, which obviously causes consternations. One also gets the sense that neither would be inclined to do so because he abhors all situations with idle small talk.

Many outer markers of his biography reminded me of a friend of mine: also high IQ, also in IT, with his private life (perennial single) and professional life now somewhat in shambles. That friend also often irritates people and avoids small talk. But while he seems similar to an autist on the surface he may be very different on a deeper level.

Whereas the autistic author (at least by his own account) has very little empathy, this friend may have too much. He can (or "can") read the faces of other humans, but somehow he does not seem to be able to trust much of what he sees. Some of his intelligence seems to stem from being constantly on the guard, as if to form models in his head about what really is going on and where he can fit in, but never arriving at safe conclusions. I know that there were unspoken tensions between his parents when he grew up. He is not obviously constrained in public and dear to some who know him well, but struggles with the scale of human relationships in between at a severe price.

My question is this: Does this ring any bells? Is there a name for this condition? Any books that I might follow-up and/or recommend?

# Answer
There are many issues packed into this question. I am pretty sure the answers will lead to many more questions.

1. People diagnosed with autism tend to perform worse than the average population on standard IQ tests, but there is evidence that alternative measures of "intelligence" (whatever that is) are more accurate and demonstrate that autistic persons, as a group, are not cognitively impaired. The high IQ of the book author is almost certainly unrelated to his autism.
2. For your friend, my perception is that many of the details that he shares with the book author are coincidental and distracting from the real problem. (The previous statement is harsh because it strongly implies that your friend has a disorder, but he might not have a disorder.) I believe your friend's IQ and occupation are irrelevant.
3. Let's take a break from your friend and directly address the question, "Does a condition exist that resembles autism, but featuring much instead of little empathy?" In short, no. However, Williams syndrome is often called "the opposite of autism" specifically because people with Williams syndrome are exceptionally sociable, friendly, talkative, have relatively low inhibitions in social situations, more willing than a normal-developing person to interact with strangers, are aware of negative social actions of others but have reduced negative reactions to other people's actions (such as criticism), and many other remarkable traits related to sociability and empathy. Unlike autism, however, people with Williams syndrome, as a group, have significant cognitive impairment and important differences in physical development that affect their lives in multiple and significant ways. Williams syndrome is not the true opposite of autism.
4. Your description of your friend's social interaction are clearly not Williams syndrome. Based on your description, I would be surprised if he were diagnosed with hyper-empathy disorder, which is a personality disorder (not otherwise specified), because people with hyper-empathy disorder are hyper social and tend to prioritize the needs of others so highly that their own life is damaged.
5. In your description of your friend, some phrases jumped out at me: "life now somewhat in shambles", "irritates people", "not ... able to trust ... what he sees", "constantly on the guard" modeling (evaluating?) the actions of other people, and "never arriving at safe conclusions \[about the intentions or actions of other people\]".
6. ***If*** your friend has a disorder (please start with the assumption that he does not have a disorder), I feel your description most strongly points towards borderline personality disorder. I feel this because I sense a lack of stability and predictability and relatively poor ability to form typical relationships with most people. You mention he has some good relationships, but I am speaking to my impression that the majority of his relationships and interactions are disordered in some way.
7. On the other hand, many of the things you mention suggest some type of paranoia, most especially paranoid personality disorder. If he is constantly evaluating other people for potential threats and regularly perceives threats then that is well outside of normal emotional reactions. But paranoia is most often accompanied by schizoid or schizophrenia symptoms and you did not describe anything that suggests either issue to me. Still, it is possible to have PPD without schizoid disorder *and* PPD and BPD are common bedfellows, so it is possible that your friend is struggling with both disorders.
8. Finally, if you don't mind, I want to suggest a small shift in perspective. A "disorder" is *anything* that interferes with normal life functioning. Hoarding of mustard could be a disorder if it interfered with normal life functioning. The specific label, such as autism, BPD, or PPD, is most useful to professionals creating a treatment plan. For the rest of us, one of the best ways to help our friends is to pay little attention to the label and to pay a lot of attention to anything that is interfering with normal life functioning. Let a professional therapist try to figure out if the disorder was triggered by daddy issues or a car accident. As the person's friend, and as a non-professional, it is much easier for you to help gently steer your friend away from actions and situations that will interfere with normal life functioning and towards habits and actions that will allow your friend to have a healthier life.

In any event, whether or not your friend has a disorder, he is lucky to have people in his life who notice that his life is in shambles *and* want to help him improve things. Kudos to you.
> 2 votes

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Tags: autism, empathy
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# Question
Title: What is Intelligence? Is it based on prediction capability of an agent?
I have the intuition that at a first level is the capability of an individual to predict outcomes of her/his/its own actions in a environment were he/she/it has familiarity with (don't you feel stupid when you find yourself stranded in unknown environment?).

Then at higher level intelligence should correspond to be able to predict the outcomes of the actions of the other agents in the same environment, especially if they have a significant impact on the subject autonomy.

Does my intuition make sense?

# Answer
> 1 votes
There is no agreement among scholars about what intelligence might be. You must keep in mind that we cannot directly see intelligence. We don't even know if it actually exists! The idea of intelligence was invented to describe what we *think* might be the cause of certain observable behaviors, but there are others who think that we are throwing together disparate things in one pot that are caused by a whole variety of different powers.

Think of it like you think of love. Does anyone really love anyone? Or do we only follow a bunch of emotions like sexual attraction, fear of being alone, and so on? And even if there is "true love", what is it? Is it the love of a mother for her child? The love of a person for his job? The love of a teenager for an unattainable celebrity?

Similar confusion and doubts pertain to the concept of intelligence. Is there such a thing as a unified intelligence? Or is it made up of a set of partial intelligences (verbal intelligence, mathematical intelligence, spacial intelligence, and so on)? Or is there no "intelligence" at all and only things like memory capacity, processing speed and so on? And even if there were such a thing as general intelligence, is it the actual current ability to solve a problem, or the level of the most difficult problem you could potentially solve if you were trained to your maximum? Is it the ability to find a solution fast, or to find the best solution?

Psychology tries to avoid the pitfalls of these concepts and rather investigates the observable behavior itself: e.g. mate choice in the case of love, or problem solving behavior in the case of intelligence. Because that way we can all agree on what we are talking about, and it can be measured and quantified and interventions can be planned.

Intelligence is not a really useful concept.

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Tags: intelligence
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# Question
Title: Where to find a study on women and selfies?
I have recently read the following Yahoo article: Guys, this is why you should never post too many selfies on social media.

This article describes a study that correlates selfies taken by men and their psychology.

So my question is where to find a similar study about women?

# Answer
The Yahoo Lifestyle website gives a popular description of the following study:

**Fox & Rooney**. The Dark Triad and trait self-objectification as predictors of men’s use and self-presentation behaviors on social networking sites. *Personality and Individual Differences* **76** (2015) 161–165

The study basically concludes that in a population of males (and I quote from the abstract):

> Self-objectification and narcissism predicted time spent on SNSs. Narcissism and psychopathy predicted the number of selfies posted, whereas narcissism and self-objectification predicted editing photographs of oneself posted on SNSs.

With regard to females, the authors justify their choice of a male population on p.162 at the end of the Introduction, and I quote:

> Although some research on SNSs and other interactive media has shown a relationship between use and self-objectification among females (e.g., Fox, Bailenson, & Tricase, 2013; Fox, Ralston, Cooper, & Jones, in press; De Vries & Peter, 2013; Meier & Gray, 2013; Vandenbosch & Eggermont, 2012), at this time little is known about men. Given previous findings with females, we anticipate that trait self-objectification will be associated with greater social networking site use \[...\], more frequently posting selfies \[...\], and more frequent photo editing \[...\] by men.

In other words, **in females the relation between self-objectification and use of interactive media was already known. The authors have therefore addressed the issue in a population of men.**

Sifting through the studies cited in the Fox & Rooney article, and taking into account that your question emphasizes your interest in selfies, the De Vries and Peter study cited in the quote above is probably the reference you are after:

**De Vries and Peter**. Women on display: The effect of portraying the self online on women’s self-objectification. *Computers in Human Behavior* **29** (2013) 1483–1489
> 7 votes

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Tags: social-psychology, abnormal-psychology, experimental-psychology, social-desirability, social-neuroscience
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# Question
Title: Evolutionary game theory in the cognitive sciences
Game theory models something very relevant to psychologists (in particular social psychologists): conflict and cooperation between decision-makers. Unfortunately, classical game theory demands that these decision makers are rational (in a mathematically precise sense). This definition of rationality is challenged empirically (by work like Tversky & Shafir) and on a theoretical level (by complexity results on finding or approximating Nash equilibria: a PPAD-complete problem).

Economists and mathematicians (and others) have taken two approaches to overcome this problem. The first is top-down approach of limiting the agent's abilities from an all-powerful rational agent down; this is the bounded rationality approach. The other is the bottom-up approach of evolutionary game theory: start with the simplest agents (that can't even make decisions) and have natural selection, imitation, or another simple dynamic process evolve the population over time. This seems to dove-tail nicely with the biogenic approach to cognition.

Are there examples of the tools of **evolutionary game theory being used in social psychology** or other sub-disciplines of the cognitive sciences? Is there a **survey (or book) on EGT's impact on the cognitive sciences**?

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### Related question

What are good examples of applying dynamical systems in cognitive science?

# Answer
There are some mentions of Evolutionary Game Theory in this Behavior & Brain Sciences (BBS) article by Andrew Colman (2003). The main article itself only has a brief section on EGT. However, like all BBS articles, there are short commentary articles after the main article. A few of these deal directly with EGT. I was able to find the relevant articles within the larger document by doing a find for "evolutionary game theory".

There are a few references throughout the BBS article to studies within cognitive science using EGT. One particularly relevant one to your question is Colman & Wilson (1997). They modeled antisocial personality disorder in an evolutionary game, to show that stable states arise in a variety of situations in which some of the agents behave antisocially. They treat this as a model for explaining why there seems to be a relatively stable proportion of people who behave in an antisocial manner across societies.
> 3 votes

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Tags: reference-request, social-psychology, mathematical-psychology, evolution, game-theory
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# Question
Title: How are hallucinations generated, is it related to dreaming?
I was thinking how powerful auditory and visual hallucinations must be, for the individual experiencing them to be unable to distinguish them from reality. I, personally, have not experienced a hallucination, but have experienced vivid dreams and know that when I'm dreaming it can seem real, and at that point, that is my reality (even though I am asleep).

Is there a correlation between the part of the brain responsible for dreaming and hallucinations?

What generates hallucinations, to make them indistinguishable from reality?

# Answer
Psychosis results in hallucinations. States of psychosis are thought to be like seizures caused by imbalanced levels of at least dopamine and serotonin. Psychosis like depression creates new pathways in the brain which allow for the senses to be flooded with internal information. The person who is experiencing hallucinations may be forced by the psychosis to think that it is real. Some are able to realize that the hallucination is not real. For instance, it is a common condition of humanity to have isolated instances of hallucinations. People hear music when there is none or think someone calls their name but no one did. Normal people are able to recognize that there was no music and no one called their name.

Psychosis can be caused by extreme excitement. Excitement alone impairs judgment but if it goes to an extreme a person can become psychotic and begin to hallucinate or have other odd behaviour.

Often times people schizo type and bipolar disorder are accompanied with insomnia. If the illness progresses far enough the sick person can become caught in a state between awake and asleep. The hallucinations are combined with greater degrees of dissociation (day dream).
> 2 votes

# Answer
The short answer is "Yes" - there is a practice of taking conscious control of one's dreams called "Lucid Dreaming". This practice involves a number of techniques used to achieve awareness and control within a dream.

One of the techniques, called Wake Induced Lucid Dreaming (WILD) involves staying still in bed for extended periods of time. After a fairly long time (~45 minutes) the dreamer slips into a dream while being awake. **The transition between waking state and dreaming state, when experienced consciously features numerous different types of hallucinations.**

The phenomenon has been confirmed by a lot of people, the types of hallucinations most frequently described are: feeling "vibrations", hearing things, seeing things, feeling a presence of others in the room, falling through one's bed or being drawn out of the body. In most cases the dreamer is acutely aware that everything that is being felt is just a symptom of the WILD transition phase.

Because of the diversity of hallucinations experienced, I would conclude that dreaming and hallucinations are connected.
> 1 votes

# Answer
One way of describing it is that the brain is experiencing a case of non-shared deception. I say, "non-shared deception", for the following reasons....

People see cars stop, move, move faster, slow down, and stop again. However, a simple analysis of "motion", via the use of nothing but the mind, soon leads you to seeing the fact that all cars are constantly in motion, and that they never stop moving. This constant motion applies to all objects. All that can be done is change the direction of this constant motion as it is constantly on the go within a 4 dimensional structure known as Space-Time.

This simple ABC analysis of motion soon has you independently understanding Special Relativity, and it also has you independently, and successfully, creating all of the Special Relativity equations with absolute ease.

(To watch this easy breezy analysis of motion in action, goto youtube videos 1-9 at http://goo.gl/fz4R0I )

Thus, those who see objects, such as cars, speed up and slow down etc., are those whom are obviously "Seeing something that isn't really there.". They are experiencing an hallucination.

Now if the outward extension of the mind is reduced to an even smaller scale, via drugs or whatever, then the magnitude of the ongoing hallucinations are magnified even further, magnified to an even greater scale than the hallucinations that are being shared on a global scale.
> -3 votes

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Tags: cognitive-psychology, abnormal-psychology, cognitive-neuroscience, psychiatry, hallucinations
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# Question
Title: Regarding the mind and what it can affect
About the question 'Can the mind mind affect the brain?': Some responses are 'no' because the mind is a physical 'thing' or structure (if I read it correctly). Yet if the Mind is only a physical structure why couldn't the mind affect the brain if they are **both** physical systems? The brain, the physical system regarding active neural excitation events and the mind, the physical system dealing with the manipulation and organization of 'established' patterns of neural-signalling. The 'higher-level' organization of the physical system, the mind, could manipulate or alter the physical system called the brain.

# Answer
> 5 votes
The question that you are referring to is worded in a way that I think is leading to the confusion. The question in the title is "Can the mind affect the brain?" but in the question body the final question posed is "Does \[a thought producing a tear\] not contradict the (physical) law of cause and effect?".

The answer is *yes* to the title question: the mind can affect the brain. The answer is *no* to the question posed in the body: it is not a contradiction of the law of cause and effect because the mind is a physical entity.

So you are exactly right, that the two are mutually interactive.

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Tags: neuroscience, philosophy-of-mind
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# Question
Title: Can information theory be applied to human interactions and communication?
I am not sure if this question is better suited for the computational science SE.

I learned a bit of Shannon's information theory in a course I took last year. In the class it was defined as the quantitative relaying of information between a signal and a receiver across a medium that introduces noise. In all the examples we explored it was typically defined in terms bits of information that can be quantified and conveyed across the communication channel. Some examples we discussed were data compression, the transfer of DNA from parent cells to daughter cells, and aspects of speech/written words.

Let's say two individuals are in conversation. One speaks a phrase communicating his current state of mind. He then speaks the phrase out loud. The second individual hears this phrase. She then processes it based on her own brain and the way it functions and produces a response.

Here the signal would be the person speaking the phrase and the receiver would be the person interpreting the phrase. Could we argue that the "noise" in this communication is the subjectivity of the two people? The first person is attempting to convey information that is derived from his particular subjective state and whatever patterns were generated by his brain from his experiences. The second person would have to weight this information against her subjective state and past experiences with the first person. This might introduce "noise" that would affect the intended interpretation of the phrase.

Essentially, my question is with regards to social communication - sometimes you must know the appropriate way to phrase something so that the correct information is conveyed and is not subject to misinterpretation.

**Question: Would this be a proper application of information theory?**

Note here that I am not talking about the actual information content of the sentences themselves (which may be noisy if imprecise language is used) but the interpretation on the part of the two people in communication.

# Answer
Information and signal detection theory are commonly applied to cognitive situations. Examples include TSA agents searching for weapons among carry-on bags and sonar operators attempting to discern ships from fish. In addition, information theory itself is highly general, and has been proven to apply across disciplines. So I do think the premise is valid.

However, the example does not list an application, per se- it simply describes a situation where one might think about coming up with an information-theoric approach. Such an approach would certainly involve a lot of research because there are many confounding factors in communication between humans (not the least of which is the cognitive framework of the receiving individual). You would need to carefully define what is signal, what is noise, and where the boundaries lie. I contend that this would be particularly difficult in the general case.
> 1 votes

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Tags: social-psychology, computational-modeling, communication
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# Question
Title: What's the function of the clean-up memory in SPA?
When I read about cognitive models that use the Semantic Pointer Architecture (SPA), such as a model for general intelligence, I often see a component called the "clean-up memory"? What's the function of this component and how does it function vary from SPA model to SPA model?

# Answer
> 4 votes
SPA is used (among other things) for combining (binding) and extracting (unbinding) knowledge representations for processing. This is a (purposely) lossy compression. In the "Learning Rule Generation for Induction" case, the clean-up memory is used to convert a general transformation that is being learned (lots of different transformations convolved together) into a transformation that is already known. So basically it's associating the in-progress transformation to a known transformation.

This is why the "clean-up memory" is also called the "associative memory" in other SPA models and in Nengo 2.0.

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Tags: cognitive-modeling, nef, spa
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title: How long do dreams last?

text:
# Question
Title: How long do dreams last?
What is the relationship between time perceived in a dream and time in the external world?

Is time running in dreams always faster than the time running in the real world? Is it ratio of real time and dream's time?

# Answer
In experiments conducted in the 1950's, William C. Dement, a pioneer sleep researcher, asked subjects to write down their dream content. What he found was that the number of words in the subjects' dream diaries correlated strongly with REM time, suggesting that **perceived dream time matches actual dream time**.

Although REM time is no longer considered a reliable measure of dream time, this paradigm of using Total Word Count (TWC) or sometimes Total Recall Count (TRC) from dream diaries (referred to as sleep mentation reports) to measure dream length, is in common use today.

Further validation of this method was found in subjects with RBD, a disorder that features twitching and movements during sleep, and other parasomnias such as sleep talking. Here, timings in dream reports match recorded timings of muscle movements and sleep talking. In other experiments, external stimuli delivered during dreaming \- such as sounds, smells, or touch - are incorporated into dream content, again with timings matching reports.

More recent research by Matthew Wilson focusing on memory consolidation in dreams adds an important detail to this however. Dream sequences are often disjointed, on a faster time-scale, and sometimes in reverse order with respect to the events they reflect. Think of it this way: If you watch a video in fast-forward (ie, skipping frames), then the time in the video is faster than real-time, but you are nonetheless aware that you have been watching for a shorter period of time. The same appears to be true of dreaming: Dreams may play in fast-forward (also skipping frames), but dreamers are nonetheless aware of the actual passage of time.

In the experiments with rats traversing a maze for example, dream imagery reflected important points in the maze, such as major intersections, areas with unique smells, obstacles, etc, rather than long boring monotonous hallways. Think of it like a tourist taking photos of a hiking trail: The photos are not evenly spaced out in time - there are fewer photos from boring parts of the trail, and more photos from the interesting parts. That is, dream content does not necessarily play at a constant speed relative to real-time - it may be faster (skip frames) or slower (add frames), and change over the course of each dream.

Note: Dreams are typically 30 minutes or less in length.
> 17 votes

# Answer
I would like to bring up that there is also an opposite study about sleep duration than described in the previous answer.

Daniel Erlacher at the University of Bern conducted an experiment to analyze brain activity during a lucid sleep.

When he asked subjects to complete an activity, it took 50% longer to perform it in lucid sleep than in real life.

This could explain why many people see dreams of running in slow motion.

Front. Psychol., 16 January 2014 | doi: 10.3389/fpsyg.2013.01013
> 10 votes

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Tags: sleep, dreams
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