# Question
Title: Can I teach my brain to understand binary?
The question is if I could teach my brain to understand binary codes (for example, ASCII) just like I teach it to understand English, French or any other language.

That includes:

* not to translate it each time I read some binaries, like 01100001 01100010 automatically reads 'ab'.
* understand both written, pronounced and somehow sound-coded form (like Morse)
* write and say it naturally

The idea is not to teach computer speak to people, but to teach people speak to a computer in his language. In general, human brain can be taught anything. It is a programmable computer. However, you can only program it very slow. If you can teach your subconscious to multiply numbers, why can't you teach it to encode MD5? Or decoding HTTPS data given a key? Even bruteforce?

So the question is if there are any researches on the topic, or the people who tried such learning? Are there any techniques? Also, what if we teach a 2-year old child this language, will it be natural for him just like the English is natural for English-grown child?

P.S. Some upgrade of this idea is to place some radiowaves-to-soundwaves direct converters and "listen" to the radiosignals around you. Somehow "spy" on neighbours Wi-Fi.

P.P.S. I've asked this questions on datascience stackexchange, and the community suggested moving it here. However, it is also moved to lifehacks, where I received a few answers: https://lifehacks.stackexchange.com/questions/7575/can-i-teach-my-brain-to-undersrand-binary/

# Answer
Can I interpret your question as "Can a human brain perform complex computational tasks, like encode MD5, on par with a computer?"? To answer that question, I'm going to have to say no, that's why we invented computers in the first place.

But, I think you're asking the question from more of a human performance standpoint, rather than strictly a language or computer science standpoint. You said in your comment, "I believe that there are pretty no limits to what a brain can learn". That's a fantastic attitude, but sadly, it's simply not true. It *is* true that you can study and try to learn anything, but everyone's performance is going to be limited individually. Some people may master something and others may struggle, given the same amount of time to practice.

The brain is mysterious, but we do know that our thoughts and movements are controlled by neurons firing. The brain adapts the firing patterns of the neurons in order for us to "learn". More neurons doesn't necessarily imply better performance or learning ability.

I would say that a fixed number of neurons being present in the brain at any one moment, combined with the fact that it takes some amount of time for a neuron to fire and react, would suggest there is a hard cap on a persons processing power at any one time. A person can't immediately become better with the resources they have.

Genes, diet, and other factors would affect a persons biological ability to grow new, well-functioning neurons, and their ability for their brain to "tune" existing neurons in order to learn. General health would affect this, and since a person can't be "unlimitedly healthy", it follows that there is some limit on the person's ability to create and "tune" neurons. A person can't unlimitedly increase their resources.

These two points suggest that our performance ability is ultimately limited by time, and I think there is simply not enough time to learn to speak binary at a fast enough and large enough scale to be useful EG listening to wifi. And if you consider today's data rates, 100MB/s just as an example, this would probably be beyond our ears' sensory perception capabilities anyways. I believe there are studies on the "rate" at which we can perceive sensory stimuli.

To provide another example to consider, I'm thinking about weightlifting, since the world deadlift record was just broken at 500kg. There's no "limit" on how much weight a person can lift, but there is certainly a limit to the rate at which you can train your body, and a limit on the amount of time you have to do it.

So in order to learn to decode HTTPS naturally in your brain, you would simply need to make exponential gains in your brains biological/physical ability to process and compute. There's no reason you can't, but we haven't figured out how to do that yet. Simply spending all of your time trying to learn it would certainly get you *somewhere*, but certainly not enough to "speak HTTPS".
> 1 votes

# Answer
Quite a bit of foundational research on skill acquisition is on how people learn to send and receive morse code. I'm no expert at morse code but it seems like it shares quite a bit with binary.

For example, here is a graph of letters per minute that an operator could receive as a function of weeks of practice (Bryan & Harter, 1897).

A general principle is that gradually people move from identifying letters to seeing larger patterns like words and phrases.

Reading is a little different to receiving information aurally. But I imagine some similar principles would apply. If anything, I imagine that ability to recognise patterns visually would make the task of reading binary easier. That said, binary does seem far from optimal as a system for encoding letters in terms of efficient visual processing.

Bryan, W. L., & Harter, N. (1899). Studies on the telegraphic language: The acquisition of a hierarchy of habits. Psychological Review, 6(4), 345.
> 9 votes

# Answer
If you look at ancient form of writing called cuneiform, that is as close to binary code as you can get. People did learn to read/write it in ancient times, but from my understanding it was so hard that it required years of training.

In terms of teaching people to "speak computer" - this is very far off mark, computer programs are extremely long and complicated sequences of characters. For example something like "print the word loop 10 times", expressed as:

```
 for(int i = 0; i< 10; i++)
    {
        printf("loop");
    }

```

gets translated into assembly language, where the program will move different numbers to different registers, and then those instructions are translated into binary. The number of intermediate steps is very large, and the resulting sequence of binary would be meaningless, unless you know assembly language.

For example:
> 3 votes

# Answer
It is absolutely possible but it would be a step backwards. In the early days of computing, punched cards and punched tape were used for input and output. They contained binary in the form of punched holes.

It was well known that many individuals could read directly from the tape. Here is an old picture of just that. http://i2.cdn.turner.com/cnnnext/dam/assets/121121034453-witch-computer-restoration-uk-story-top.jpg

In case the link fails, you can find it yourself by Googling "61-year-old computer springs back to life" By John D. Sutter, CNN

The problem is that programs written directly in machine code have to be documented by hand and are very difficult to maintain. This is the whole reason that high-level computer programming languages were developed.

I can say from personal experience that I can look at many binary numbers and instantly recognise them both as numbers and as ASCII but I would have no desire to improve this skill any further.

Incidentally it is also possible to 'read' binary by listening to it. In the days of the ZX-Spectrum, programs were stored on audio-tape and certain patterns were very recognisable when played back as sound. It would certainly be possible to acquire this skill to a very high degree if it was taught early enough to a child but again, I don't think it would be very useful. Machines can do it so much better.
> 3 votes

---
Tags: learning, brain-computer-interface
---


# Question
Title: Can one personality kill another personality?
For a person with multiple personalities, can one personality murder or kill another personality such that the killed personality never surface again?

Did it ever happen or studied?

# Answer
> Far from being simply encoded in the genes, much of personality is a flexible and dynamic thing (Mischel & Shoda, 1995) that changes over the life span and is shaped by experience (Roberts, Walton, & Viechtbauer, 2006). *Can Personality Be Changed?* by Dweck

After searching for related case studies, this is the closest I could find: "Deathman, age 27, intervened when John, Gail and Diana argued." -- Four Cases of Supposed Multiple Personality Disorder: Evidence of Unjustified Diagnoses This women's multiple personalities fought each other (even though the authors doubt she had MPD).

Perhaps "kill" is not the best word.
> 4 votes

# Answer
In working with MPD patients, I understand the creation of personality in the context of MPD to be different than the creation of personality of the core individual. Our personalities are formed both from DNA and from our interactions with our environment. In the case of someone who has MPD, each personality serves a purpose. Occasionally, individuals with MPD will develop a personality that demonstrates dominance or the need to fight. This dominance or fight instinct is their primary coping mechanism. If this particular personality feels threatened by one of the other personalities, or perceives one of the other personalities to be weak (causing weakness of the whole), then the one can attack the other. How the brain creates or destroys personalities of an MPD is unknown. Most often it simply appears that the personality that was attacked is hidden, dead, or reabsorbed into the collective. The thoughts, feelings, and even memories from that personality can simply be gone. Where they "go" is also unknown. It is not believed that a formed personality is stored in memory the way we store other known information. It isn't like amnesia. But, there can be clear gaps in what one remembers. The core personality will often recall that there was once a personality that existed, but will be unable to recall the details held by that personality.
> 0 votes

---
Tags: cognitive-psychology, personality, personality-disorder
---


# Question
Title: How is "being in a flow" explained cognitively?
When wathcing the European Championship athletics, I hear many people talking about being in a "flow". Flow is defined as follows:

> Flow is an optimal psychological state that occurs when there is a balance between perceived challenges and skills in an activity (Csikszentmihalyi, 1990). It is a state of concentration so focused that it amounts to absolute absorption in an activity.

This sound nice, but to me it is still a quite abstract definition and it is not really clear to me how being in a flow works. **Is there a more low level (cognitive) explanation of being in a flow?**

*I thought that this paper could shine some light on the subject, but I am unable to access it.*

# Answer
There is a six-step breakdown of 'the flow' or 'zone' from it's creator Mihály Csíkszentmihályi

> 1. Intense and focused concentration on the present moment
> 2. Merging of action and awareness
> 3. A loss of reflective self-consciousness
> 4. A sense of personal control or agency over the situation or activity
> 5. A distortion of temporal experience
> 6. Experience of the activity as intrinsically rewarding, also referred to as autotelic experience

Which can be found from his website

There's also a photo available that denotes when flow would be considered achieved. (**Upper Right**)

For even easier understanding, an example of the six steps in order from my personal life,

1. When implementing or working on a new project in Excel/VBA (Work I'm very comfortable with) I usually start with music to block out distractions and assist in focusing.
2. As my process moves on I'm no longer able to hear the music, though it's still on. My brain is queuing next lines of code to test and my fingers are an output.
3. I'm less focused on mistakes, mishaps, meetings, or just general things on my plate. My only issue is my task-at-hand
4. I am the author and implementation. The code is mine. It's finished when I am.
5. In deep focus, a day that started at 9am and feels like may be 10am is actually closer to 1pm... and I should eat.
6. Every proper step IS rewarding, I'm challenging myself with a problem and completing work.
> 2 votes

---
Tags: cognitive-psychology, performance, sport-psychology
---


# Question
Title: Is it counter-productive to study while tired?
I've noticed I retain a much smaller fraction of the information I consume when I'm tired compared to when I'm well slept. Not only that, but I typically have to revisit the same material more times due to this issue, and at that point the information no longer seems new and exciting.

Outside the context of academia and deadlines, if one is self-studying new material is it more beneficial to wait till they're better slept or should they power through the fatigue?

# Answer
Yes. When studying sleep is crucial in consolidating memories. Recently a wave of research and opinion has hit around optimizing learning, sleep is always mentioned as key. To prominent authors are Benedict Carey and Barbara Oakley. There work is much easier to process than the below research paper, but we like well researched answers!

So here we go, why studying while fatigued is counter-productive and the underlying mechanism of memory consolidation.

> Whereas older research concentrated on the role of rapid-eye-movement (REM) sleep, recent work has revealed the importance of slow-wave sleep (SWS) for memory consolidation and also enlightened some of the underlying electrophysiological, neurochemical, and genetic mechanisms, as well as developmental aspects in these processes. Specifically, newer findings characterize sleep as a brain state optimizing memory consolidation, in opposition to the waking brain being optimized for encoding of memories

Further

> Consolidation originates from reactivation of recently encoded neuronal memory representations, which occur during SWS and transform respective representations for integration into long-term memory.

This work is available for free from the NCBI here
> 5 votes

---
Tags: learning, memory, sleep
---


# Question
Title: Introduction or Tutorial on Continuous EEG Collection Procedures and Initial Processing?
Are there any tutorials or introductions (specifically not slides from talks) on the very basic details of EEG data collection and processing? Things like:

* Discussions of reference systems (montages)
* The "usual" sequence of initial processing steps
* Identification of artifacts by type and usual procedures for dealing with them
* Precise methods of electrode placement (such as good ways to measure electrodes on the head, etc.)
* Etc.

Basically I am looking for a sketch of standard or usual procedures used either widely in EEG or, failing that, commonly in EEG studies that make use of longer, continuous recordings (as opposed to ERPs). What is sometimes called "lab lore" or the common things you need to know that are often glossed over in journal articles. (Something akin to the very introductory textbooks available for fMRI.)

The usual response to this is Steven Luck's book: Introduction to the Event-Related Potential Technique -- but that book is so centered on ERP recordings, that it is very hard to follow for other types of EEG collection, such as long continuous recordings. On the other side, journal articles are generally too brief about their recording and initial data analysis procedures to replicate their work.

**Additionally, open-access/open-source information is preferable**; we don't have the money for the usually priced textbooks. (I'll accept those if there are no open answers, but open is better!)

Note that this other article "Getting Started with EEG" either recommends Luck's book (which is good, but too ERP focused) or begs the original question of learning *how* to collect and process EEG by basically saying "just collect it on yourself and do it." So this is strictly not a duplicate question.

# Answer
> 1 votes
There are plenty of books and courses about EEG. I personally can recommend the book from Mike Cohen "Analyzing Neural Time Series Data". It´s well written, simple and condense introduction into EEG, electrophysiology, experimental design, data acquisition and, mostly, basic-to-advance analytical techniques. Book comes with the demo data and code for the analysis in Matlab.

Alternatively, you can go directly to the website of any big EEG community that developing an analytical toolbox (like EEGLab, Fieldtrip, or Brainstorm). Each of them provides sufficient amount of the introductory materials and step-by-step tutorials, including video lectures.

# Answer
> 1 votes
There is a new FREE introductory document on the brain and EEG. You can download it over here: http://www.advancedbrainmonitoring.com/free-eeg-pocket-guide-download/

Another popular book is An introduction to event-related potentials, by Steven J. Luck.

---
Tags: cognitive-neuroscience, experimental-psychology, eeg
---


title: Suggestion for wearable EEG headset

text:
# Question
Title: Suggestion for wearable EEG headset
We need wearable EEG headset with raw data output accessible from various platforms. I heard that devices like that have commonly the output encoded and available adapters are designed for one or just few platforms.

What we really prefer is device with output with standard (or well known) protocol, so we can create our own adapters.

Do you know what EEG wearable headset is the best for this purpose?

# Answer
Emotiv EPOC+ Research Edition can be used on Windows, Linux and Mac.

It has 14 electrodes (+2 reference electrodes) and is used in several publicized studies. You can access raw data via their software "Testbench" and output it as CSV or use third party software like OpenVibe, BCI2000 and EEGLab.

But the little drawbacks are:

* It is a wireless device, so you really should put the usb dongle for wireless signal transmission with a long usb cable directly on the device, to overcome signal distortion
* The reference electrode processing is done within the device
* It seems to be more intended for consumer use than for medical use

**EDIT about realtime usage of EPOC+ and OpenVibe Software:**

There are studies and projects using the EPOC+ in realtime with OpenVibe. OpenVibe has a built in driver for the EPOC+ Research Edition

https://www.google.de/url?sa=t&rct=j&q=&esrc=s&source=web&cd=6&cad=rja&uact=8&ved=0ahUKEwiz2c-FpuXJAhVBhA8KHY0tD-IQFghbMAU&url=http%3A%2F%2Fwww.mtg.upf.edu%2Fsystem%2Ffiles%2Fpublications%2FSergio%2520Giraldo%2520-%2520Brain-Activity-Driven%2520Real-Time%2520Music%2520Emotive%2520Control.pdf&usg=AFQjCNEi0w9wT2eMlUUxvUyLj2jsKL1ewg&sig2=eJMv2T\_OjE4tHr6JnbV4IA&bvm=bv.110151844,d.ZWU

And in this project two devices can be used, the EPOC+ and the the ***Enobio***, which seems to be an intersting device, too. But I do not have enough knowledge about the Enobio to recommend it. But it might be even better as the EPOC+, as they have models with more electrodes. This is the realtime application for the two devices: https://github.com/marcelfarres/Play\_Your\_Mood

By the way, OpenVibe features drivers for quite some EEGs, but it can only be used on Windows and Linux. On Mac you would have to compile it yourself.
> 2 votes

# Answer
Have you looked into OpenBCI?

You can view their latest kickstarter here:

https://www.kickstarter.com/projects/openbci/openbci-biosensing-for-everybody
> 2 votes

# Answer
Advanced Brain Monitoring has amazing high quality EEG systems that are almost as good as medical grade equipment (Reference will follow).

There are several choices you can make. There is the X-10 (9 channels plus mastoid and ECG), the X-24 (20 channels plus mastoid and ECG). Each of these systems also have accelerometers integrated. Moreover, ABM has a sleep profiler, an even simpler EEG system with fewer channels. ABM also provides neat online and offline analysis software. Definitely recommend it.

Other possibilities are the Nexus systems and Biopac Mobita. I haven't worked with them but they exist.
> 0 votes

---
Tags: measurement, eeg, brain-computer-interface
---


# Question
Title: If light travels at c, and the human nervous system's speed/perception speed<c, why aren't we not seeing or blind at some times?
If light travels at c, and the human nervous system is a lot slower than light speed, therefore it would take a lot of time for us to process what we see, why aren't we blind to what's going around us because everything we see is slowly processed at an inferior speed (let the inferior speed be defined as is less than c--the speed of light)?

# Answer
I think you are confusing speed with rate. The speed of light is how long it take to for light to get from one point to another, not how often light "events" arrive at the eye.

To give an analogy, imagine a highway. There are 500 cars on that highway. They are traveling at 70 mph. Those cars then exit the highway onto a residential rode. They are then travelling at 30 mph. Does this require some of the cars disappear? No, they are all there, just moving at a different speed.

So for vision, imagine a certain light source emits a burst of 500 photons. The light source is 1 meter away from the eye, so it takes about 3 nanoseconds for the photons to arrive at the eye. Then they are converted into electrical impulses by the eye, and processed by the brain. Let's say this takes 100 milliseconds (I am just making that number up). That is about 30 million times longer. But it is still processing the same 500 photons, it just takes longer for them (or the electrical impulses they create) to get from one point to another.
> 4 votes

---
Tags: neuroscience, perception, sensory-perception
---


title: Can we be conscious of our dreams?

text:
# Question
Title: Can we be conscious of our dreams?
During the day time, we are conscious of our surroundings and the brain does its work.

During sleep, we are not conscious. We have dreams. But the brain continues to function. After we awake though, there is only a memory of the dream experience. Is it possible to observe our dreams - that is, can we observe dreams as they occur and be conscious that we are dreaming?

# Answer
> 12 votes
Lucid dreaming is a practice in buddhism. La Berge (1980) describes in some detail how he learned to dream lucidly, and several authors managed to induce lucid dreams in their test subjects through electrostimulation, food supplements and other means. There are some popular books that claim to teach the skill, some of them written by La Berge.

# Answer
> 10 votes
During REM sleep (during which dreams seem to occur), we experience muscular atonia – our muscle can’t move. When the region responsible for muscular atonia is impaired, patients seem to live through their dreams. It has been studied in cats by Michel Jouvet.

I believe that this shows that it is reasonable to trust our subjective experience here : we are conscious of the dream while we have it – although, when we recall it later, it’s probably very much reconstructed. The relation between temporality and consicousness will remain a very tricky question, and it may actually be impossible to differentiate "being conscious as it occurs" and "having a memory of the dream experience". You can find an extensive discussion on the relation between temporality and consciousness in Daniel Dennett’s book *Consciousness explained* , chapter 6 - Time and Experience. (And there is probably more in his more recent book, *Sweet dreams* but I haven’t read it).

# Answer
> 8 votes
My answer to the question is yes. I have personally experimented (not voluntarily) conscious dreams a few years ago.To be more precise, I was conscious in dreams but also conscious to dream.

Of course this answer is a testimony, not a scientific proof, of the existence of conscious dream.
But maybe in cognitive science, many serious testimonies constitute a proof.

Let me add an interesting remark and a question:

As I said, the processes of consciousness and dream seem to coexist, but as water and oil, they tend to separate quickly:

In my experiments, when the process of consciousness started in a dream, then the dream becomes increasingly blurred and awakening occurs rapidly.
I remember to have consciously walked and explored my dreams worlds for a few minutes or quarter of an hour (to be more precise, it seemed to have had this time), but not more ...

> Is there a cognitive explanation for this quick separation ?

To make a nod to the Indian philosophy (@SaiKrishna):
*Consciousness is light and dream is shadow.<br>When the light encounters the shadow, the shadow disappears...*

# Answer
> 1 votes
Yes we can. The state is nowadays called 'Lucid Dreaming' and it is not a theory or New Age superstition. It has been scientifically proven first by Dr Keith Hearn and consequently by Dr Stephen Laberge. They both used variations of the same method, namely having the dreamer produce prearranged, measurable signals from inside the dream once the become lucid.

**Additional Subjective Info:**

Really for something like that you can try it for yourself. With a bit of discipline everyone can do it. I am exploring it myself and from the people I have told through the years five followed the methods and they were all succesful. I recommend the book 'Are you Dreaming?' by Daniel Love as it is scientific and extensive, covering all levels. If you ask me, every scientist that deals with the mind should be developing this skill. It is the ultimate introspection playground (and lots of fun).

One word of caution. If you google the term you are going to end up with billions of New Age and religious cults and wild theories about aliens, gnomes, angels, other dimensions etc.

Unless you are interested in the sociology of belief and cult formation just ignore the lot and read the science and the 'Are you Dreaming?' book (no I am not getting any money from the author).

---
Tags: consciousness, dreams
---


# Question
Title: Problem with IQ tests in Murray's "The Bell Curve"?
Murray's *The Bell Curve* came up in a discussion recently. I have a very clear memory of reading a review of the book at the time it came out. The reviewer claimed that one of the many problems with Murray's methodology was that he relied on IQ tests written in English but given to African students whose first language was French. I cannot find a link to this anywhere. Anyone have any info on this? Is the critique accurate? Is it possible that I am remembering the review of some other work?

# Answer
> 3 votes
After some significant searching myself I don't believe that what you've stated was one of the many criticisms of "The Bell Curve".

It wouldn't be impossible for the review you read to go something like,

"Murray's, "The Bell Curve" is akin to other racially biased research like as XYZ's "IQ Research", in which XYZ claimed that African students had, on average, lower IQs, but when the research was reviewed showed that those students had received a test in English, while their primary language was French."

Memory can be a tricky thing and the way connections are formed around subjects we don't use often is haphazard at best.

# Answer
> 0 votes
I don't know where you read that. I'm not familiar enough with "The Bell Curve" to inform you whether it's true or not. However, even if it were true, the language and cultural bias explanation for lower negro IQ has been shown wrong. Raven's progressive matrix IQ test has no language or cultural requirements whatsoever so it's impossible to attribute IQ scores on this form of IQ test to these biases. Sure enough, results consistent with Murray's results have been found by Rushton and Skuy.

http://citeseerx.ist.psu.edu/viewdoc/download;jsessionid=7F75E24231A12E5DD9D86E604AC1B69A?doi=10.1.1.503.9118&rep=rep1&type=pdf

---
Tags: cognitive-psychology, reference-request, iq, sociology
---


# Question
Title: How to calculate the confidence interval for $d^\prime$ (d prime)?
I have an experiment with $N$ signal trials and $M$ no signal trials and I have measure the number of hits $nHit$ and the number of false alarms $nFA$. From this I can compute the probability of a hit $p(Hit)$, the probability of a false alarm $p(FA)$, and the index of sensitivity $d^\prime$. Specifically, I define $d^\prime=z(p(Hit))-z(p(FA))$ where $z(.)$ is the inverse of the normal distribution cumulative density function.

I can also find the confidence intervals of $p(Hit)$ and $p(FA)$ with the inverse of the binomial distribution cumulative density function. Is there a similar way of calculating the confidence interval of $d^\prime$ that doesn't involve resampling the data (e.g., bootstrapping).

# Answer
> 1 votes
I haven't done much d-prime stuff for a long time, but perhaps check out the `discrim` function in the `sensR` package in R.

http://www.inside-r.org/packages/cran/sensR/docs/discrim

For example, if I understand correctly you could pass arguments like the following: a person had 60 items correct out of 100 and null hypothesis d-prime is 0 (you can specify either a null d-prime or a null probability of correct).

```
library(sensR)
discrim(correct = 60, total = 100, d.prime0=0)

```

This produces the following output:

```
Estimates for the duotrio discrimination protocol with 60 correct
answers in 100 trials. One-sided p-value and 95 % two-sided confidence
intervals are based on the 'exact' binomial test.

        Estimate Std. Error Lower  Upper
pc         0.600    0.04899   0.5 0.6967
pd         0.200    0.09798   0.0 0.3934
d-prime    1.115    0.31360   0.0 1.6958

Result of difference test:
'exact' binomial test:  p-value = 0.02844
Alternative hypothesis: d-prime is greater than 0

```

I.e., you appear to get a lower and upper confidence interval on d-prime (e.g., 0 to 1.6958). The confidence interval can be specified with the `conf.level` argument but defaults to 0.95. There's more details in Christensen (2015).

Christensen, R. H. B. (2015). Statistical methodology for sensory discrimination tests and its implementation in sensR. http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.192.6348&rep=rep1&type=pdf

---
Tags: statistics, signal-detection
---


# Question
Title: Has there been any serious research on subliminal messaging?
I certainly don't question the existence of subliminal perception which has been demonstrated many times in priming studies like those of Daniel Schacter and many others, nor do I reject the notion of the cognitive unconscious introduced by Kihlstrom (I definitely have my doubts on the psychodynamic unconscious however).

My question is about certain big claims like those of Bryan Wilson Key on subliminal messages with sexual content and consumer behaviour, those about subliminal self-help tapes or those even more suspicious that are about subliminal messages detering shoplifters to steal. Other than null results or junk science I haven't seen any convincing study supporting these claims.

On the other hand, studies by Vockey and Read (1985) challenged the effect of subliminal messages in songs and a meta-analysis carried out by Charles Trappey (1996) showed a negligible effect on consumer behavior. Also, what I get from most psychology textbooks is that the general consensus is that subliminal messaging has a poor and temporary effect (Schacter, Gilbert and Wegner, 2009).

Of course, one has to consider if subliminal perception is qualitatively and quantitatively different depending on the modality of the stimuli but then again I am unconvinced of a considerable effect of subliminal messaging on behaviour.

Any thoughts on that?

---

## References

Schacter, D. L., Gilbert, D. T. & Wegner, D. M. (2009). Psychology. New York, NY: Worth Publishers

Trappey, C. (1996). *A meta-analysis of consumer choice and subliminal advertising*, Psychology & Marketing, 13(5): pp. 517—530
DOI: 10.1002/(SICI)1520-6793(199608)13:5\<517::AID-MAR5\>3.0.CO;2-C
**PDF Available FREE from National Chiao Tung University**

Vokey, J. R. & Read, J. D. (1985). *Subliminal messages: Between the devil and the media*, American Psychologist, 40(11): pp. 1231—1239
PMID: 4083611 DOI: 10.1037/0003-066X.40.11.1231

# Answer
First we need to define what "subliminal messaging" means. I take it you mean to send a subliminal command and make someone obey that command. Based on that definition, here's some of what I find from googling:

> Effectiveness The effectiveness in subliminal messaging has been demonstrated to prime individual responses and stimulate mild emotional activity.\[3\]\[4\] Applications, however, often base themselves on the persuasiveness of the message. Importantly, research on action priming has shown that **subliminal stimuli can trigger only those actions that one plans to perform anyway: an action can be triggered subliminally only if the person already has the specific intention to perform this specific action**.\[5\] The following sections have more information on specific studies in which the effectiveness of subliminal stimuli are investigated.\[6\]\[7\] http://en.wikipedia.org/wiki/Subliminal\_stimuli

An article with several links to research on the topic:

> In 1979 that nearly 50 department stores in the U.S. and Canada had been **using subliminal messages over their music systems which had resulted in a significant reduction in both customer based shoplifting and employee theft**. One East Coast chain amounted savings of 600,000 over a nine-month period. Another story in the Wall Street Journal in 1980 stated that subliminal messaging a New Orleans supermarket resulted in an all time low within 6 months of use - from 50,000 per six month period to a figure of 13,000! Furthermore cashier shortages dropped from 125 per week to below 10 per week. http://www.realsubliminal.com/subliminal-messages-scientific-research

Subliminal advertising:

> University College London researchers have found the first **physiological evidence that invisible subliminal images do attract the brain's attention on a subconscious level**. The wider implication for the study, published in Current Biology, is that techniques such as subliminal advertising, now banned in the UK but still legal in the USA, certainly do leave their mark on the brain. http://www.sciencedaily.com/releases/2007/03/070308121938.htm

More information on subliminal and supraliminal messages and the differences:

> **Generally, there are three types of subliminal messages**: 1. Subvisual messages – visual cues that are flashed so quickly (generally a few milliseconds) that people don’t perceive them. 2. Subaudible messages – low volume audio cues that are inserted into a louder audio source, such as music. 3. Backmasking – an audio message that is recorded backwards, with the intention of playing it forward to disguise the reversed message. Does that mean subliminal messages don’t work? **A few decades ago, researchers would have agreed that subliminal messages were BS. They found little, if any, support that they were effective** (Vokey & Read, 1985). In recent decades, however, things have been changing. **Emerging research has shown that subliminal messages can influence our thoughts and behavior** (see Kunst-Wilson & Zajonc, 1980 for one of the first notable studies). For instance, **new research has shown that subliminal messages in advertising can, in fact, influence our purchasing behavior**. For example, participants in one study were significantly more likely to choose a Lipton Ice drink when they were subliminally primed with “Lipton Ice” (Karremans, Stroebe, & Claus, 2006). Pretty cool. http://www.nickkolenda.com/subliminal-messages/

..And lots more articles, if you were to ask a more specific question.
> 6 votes

# Answer
Your question rightly refers to different types of subliminal messaging, and so there is much confusion in this area. This was not helped by James Vicary's fraudulent "Drink Coca-Cola" study. Many people took this at face value and assumed that all forms of subliminal research were stopped in its tracks. In fact, the opposite is true - the controversy engaged a new generation of researchers, who have since shown subliminal messaging to work across a number of methods, context, and purposes. Studies like Vicary's are now commonplace. You Tube Link here

*If you're researching the topic, the usual sources like PubMed/Medline are useful. The US National Library of Medicine has a good collection of papers as well.*

Here is a curated list of the seminal studies.

**Evidence for Subliminal Messaging falls into two categories:**

**Group Experimental Testing**: Unlike any other forms of the so-called'talking cures' therapies, subliminal messaging lends itself perfectly to double blind testing. Here one group of subjects receive subliminal messages, and another gets a placebo recording (or a blank screen in the case of visual subliminal). These papers represent an earlier tranche of research (from about the 70′s to the mid 90′s). This demonstrated unequivocally that there is a subliminal effect, but was unable to explain the how. This came later. It is also fair to say that just like anything in the behavioural sciences, there also a handful of good and respected experiments which show subliminal messaging doesn't work.

**fMRI tests and observations:** From the mid 90′s onward, fMRI was able to show the perception and processing of subliminal information within the brain in real time.

I would hasten to add that proof that they exist/work/are effective - *does not mean that they can be used for anything and everything*.
> 4 votes

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Tags: cognitive-psychology, perception, unconscious, consumer-psychology
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title: Are women better at multitasking?

text:
# Question
Title: Are women better at multitasking?
I've observed multiple occasions where females are better at multitasking than males. It's not rare to see a lady driving a car, doing her make up and talking on the phone at the same time. Once I worked at a call center, and women were able to talk on the phone with a client and successfully perform a second task without much disruption. From my experience men have struggled with the same or similar combination of tasks.

Is there any research that backs up my anecdotal evidence?

# Answer
## Short answer

There is no consistent evidence for the fact that women are better than men at multitasking. We do know that multitasking is detrimental for performance, whether it is forced or scheduled. Women do appear to be better at planning when to multitask and, in fact, do it less often than men. **Counter-intuitively, women may give the impression to be better at multitasking because they do it less often.**

## Long answer

The notion that women are better multitaskers is deeply grained in our society. There is even an evolutionary explanation as of why that may be the case. As paraphrased by Ren, Zhou and Fu (2009):

> \[...\] females who stayed at home could not afford focusing solely on food preparation because the offspring cannot be left on their own. In other words, the structure of primitive human society exerted a strong selection pressure against females who were incapable of juggling several chores.

**Women are better**
In controlled experiments, people even found some evidence (Stoet et al, 2013;Ren et al, 2009) that supports that women are better multitaskers. In the study of Stoet et al, stimuli were shown that had two dimensions (shape and filling) each of which had two features (which determined which button to press). Only when the stimulus was presented, it became apparent on which dimension the participant had to focus. The results showed that 120 women performed significantly better on the task, compared to 120 men. As you can see from the Figure, the effect is not that large though. With enough participants, every minor effect will become significant at one point.

In the study of Ren, the participants were to perform a go-nogo task, followed by a flanker task (target identification). In a simple condition (always go, followed by a flanker task), men and women were, in a way, monotasking the flanker task. In the hierarchical condition participants had to make a decision on both go-nogo, which determined whether the flanker task had to be performed. There are two important notions that we must consider here. First of all, women improved on the hierarchical conditions! This is very surprising given the general consensus is that multitasking is detrimental for performance. Secondary task performance, for instance, is even being used as a measure for mental workload (Wickens, 1983; Kaber, 1999).

This surprising observation may be explained by the notion of the authors themselves (which is the second notion): the task at hand is not necessarily multitasking in the sense of rapid switching between (often unrelated) tasks. Instead, I think, the task in this study must be seen as sequential monotasking, in which the first task determines how the second one must be performed.

**Women are not better**
Another study investigated multitasking abilities between men and women using sudoku's and cross-word puzzles (Buser and Peter, 2011). The tasks were either performed (1) sequentially, (2) forced multitasking or (3) freely scheduled. Results showed that during forced multitasking and freely scheduled multitasking, performance dropped significantly compared to sequential task execution. No gender differences were found here.

## Then why do we think women are better multitaskers?

Stoet et al, performed two experiments. In the second experiment, three more ecological valid task were to be performed concurrently, for which the participants had eight minutes in total. The order in which they had to be performed was up to the participants. Here, less obvious differences were found. In two of the task there was no significant difference in performance. One task, the key-finding task, did show that women were significantly better. However, we must again ask, is this because of their multitasking ability?

Because the participants could decide when and how to perform the task (sequential monotasking or multitasking-wise), they were in charge of the planning. It has been shown that people are generally bad at this and performance always is affected (Katidioti, 2014; see also Provable ROI for call center rest periods?; Buser and Peter). What Buser and Peter found, however, is that **women are less inclined to multitask compared to men when given the choice.** If this is indeed the case, this may explain the fact that women performed better at the key searching task.
> 4 votes

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Tags: gender, multi-tasking
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# Question
Title: Do STDP synapses potentiate AND depress at the same time?
Do STDP synapses potentiate and depress at the same time? Consider the following scenario where two cells are connected by an STDP synapse: PRE and POST. PRE cell fires two action potentials 2 ms apart (A and C below).

Cell POST fires an action potential (B) equally between the two spikes of the PRE cell. Assuming the STDP curve is symmetrical, would this situation result in no net change of the synaptic weight?

It seems that since B occurs shortly after A, then that would potentiate the synapse. And B occurs shortly before C, then that would depress the synapse by an equal amount. Thus resulting in no net change.

Is it correct, that both depression and facilitation takes place in an STDP synapse simultaneously?

# Answer
I can't make comments yet, so in the following I will assume that by 'STDP synapse' you mean the model of a synapse using the STDP rule.

The scenario that you are describing is a triplet experiment with a PRE-POST-PRE protocol and to answer your question: Yes, in this case the STDP rule predicts both, weakening and strengthening of the same synapse and given symmetric curves the net change would be zero.

In this paper in Figure 2 C,D they address this scenario (they report a non-zero net change but I guess it's due to asymmetric STDP curves). As they mention, the STDP rule is also symmetric in a different way in that it would predict the same net change in a POST-PRE-POST scenario because it simply adds up the two spike-pair events (PRE-POST and POST-PRE). Also in Figure 2 C,D is shown that experimental results differ from the STDP predictions because they are not the same for the PRE-POST-PRE and the POST-PRE-POST case. This discrepancy is actually the motivation of the more general triplet rule that is described in the reference.
> 3 votes

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Tags: learning, computational-modeling, neural-network, plasticity
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# Question
Title: Can brainwaves from EEG be used to measure enjoyment of media?
It seems to be very hard to figure out automatically, what content I will enjoy and what content I will not enjoy.

Of course, there are methods that require me to sit in front of a computer and press yes or no when I see content to determine whether I like it or not. But not only is it tedious, it is also not precise. It is not precise, because there are always more emotions involved, it is about the state of emotions and not a single emotion.

Therefore my idea is this:

While I am watching pictures or media of other kind, my brain waves are measured. Having seen a lot of photo, there will be a certain correlation to a photo being seen and a brain reaction. I could use this information to predict which media will evoke certain emotions in me. The only drawback is that this is not a static database that can be used over time but due to my increase of knowledge it needs to be updated. But in general this should give useful information that enables prediction based on machine learning.

Will this approach give me or anyone else performing this experiment useful data?

# Answer
I think the question whether this experiment will give you useful data can be split into two parts:

1. Does the EEG reflect the emotional state ?
2. Does the stimulus (media,pictures) induce such an emotional state ?

For the first question there is a lot of research going on and this review might be a good starting point to get into the topic. Without knowing much of the literature I would guess though, that you always need some ground-truth data of the emotional state to train your classifier. This would mean that you would need to somehow 'measure' your emotional state during the EEG recording. You could avoid this by separately 'measuring' your emotional state when watching the media but then you would have to assume that it's always the same emotional state which might not be true.

If you don't want to measure the emotional state, you could also try to do unsupervised learning on the EEG signal, maybe saying that you want to find 3 different emotional states and in the best case the algorithm will give you a nice partition of your stimuli into three categories but there is no way that it can know what emotions those categories stand for.

For the second question I guess it would make sense start with a set of stimuli for which you are sure that they induce strong emotions.

All of this is speaking of general emotional states. Reducing the problem to only distinguishing enjoyment vs. no enjoyment would make it a bit easier of course but the aspects to consider remain the same.
> 3 votes

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Tags: cognitive-psychology, eeg, brain-computer-interface
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# Question
Title: Is forward associated with right and backwards with left?
The following is an observation I made in an informal sample group of about 10 people. I am looking into understanding the behavior I observed. Here is the setting:

On a computer keyboard there are the 4 arrow directions: up/forward, down/backward, left and right. Only the up/forward and down/backward keys are functional. On the screen is a first-person view that can rotate left (counterclockwise) and right (clockwise). The up/forward and down/backward keys are to be bounded to those rotations, so that pressing one would rotate the view in the bound direction.

I've noticed that most people bind the up/forward key to the right rotation and the down/backward key to the left rotation. I thought that this has to do with handedness, but it seems not to be the case. The exact numbers don't matter because there is not enough here for statistical significance. It could be that there is an association of clockwise rotation with (time) moving forwards, and same for counterclockwise.

Is there any reasoning for this, or studies on this?

# Answer
> 4 votes
It may have to do with language.

The idea that language influences thought is called Linguistic Relativity:

> The more accepted weak version claims that linguistic categories and usage only influence thoughts and decisions.

Lera Boroditsky summarizes research on the influence language has on direction and time:

> English speakers tend to talk about time using horizontal spatial metaphors (e.g., "The best is ahead of us," "The worst is behind us"), whereas Mandarin speakers have a vertical metaphor for time (e.g., the next month is the "down month" and the last month is the "up month"). ... Imagine this simple experiment. I stand next to you, point to a spot in space directly in front of you, and tell you, "This spot, here, is today. Where would you put yesterday? And where would you put tomorrow?" When English speakers are asked to do this, they nearly always point horizontally. But Mandarin speakers often point vertically, about seven or eight times more often than do English speakers.

And in more detail in a Scientific American article:

> ... my colleague Alice Gaby of the University of California, Berkeley, and I gave Kuuk Thaayorre speakers sets of pictures that showed temporal progressions—a man aging, a crocodile growing, a banana being eaten. We then asked them to arrange the shuffled photographs on the ground to indicate the correct temporal order. We tested each person twice, each time facing in a different cardinal direction. English speakers given this task will arrange the cards so that time proceeds from left to right. Hebrew speakers will tend to lay out the cards from right to left. This shows that writing direction in a language influences how we organize time. The Kuuk Thaayorre, however, did not routinely arrange the cards from left to right or right to left. They arranged them from east to west. ... in Aymara, a language spoken in the Andes, the past is said to be in front and the future behind. And the Aymara speakers’ body language matches their way of talking: in 2006 Raphael Núñez of U.C.S.D. and Eve Sweetser of U.C. Berkeley found that Aymara gesture in front of them when talking about the past and behind them when discussing the future.

This suggests that if you reversed the exercise, binding the left/right keys to movement forward or back, then you might get different results from Hebrew speakers than English ones. And if you presented this exercise to speakers of Kuuk Thaayorre, then the results might depend on which way the keyboard is oriented - ie, you would get different results depending on whether the keyboard faces East or West!

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Tags: lateralization, preferences
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# Question
Title: Are there psychiatric medications that have an anti-tolerance effect?
Patients usually develop tolerance to their psychiatric medications when used over a long period of time. This is because of how the brain gets used to the dosage in order to reach equilibrium again. Are there any that have an anti-tolerance effect? Which means over time you would need less and less of the medication to get the same effect?

# Answer
I don't know of any drug therapy that becomes less with use, especially for treatment of psychological disorders. The only instance I would know of is an individual is attempting to remove a medication to try something new/ different. The basic reasoning is described below.

There is an understanding of the pharmacodynamics of how the drugs or medications are believed to behave when interacting with the brain. Receptor cites can also be a factor, and will depend on if the medication is believed to be an agonistic action, or an antagonistic action (does it block receptors from uptake, or does it increase?). Either way, the neurobiology of the brain at the synapse of the neurotransmitter is believed to change, and the amount of certain chemicals could change as well.

Another few contributing factors would be how the therapeutic range for the medication is thought of by the pharmacological community, or how much dosage an individual needs for the medication to be therapeutic. Anyone that has been on a medication longer-term might experience withdraw effects when reducing the medication because the brain isn't able to take over production of the "needed" neurotransmitters. A half-life discusses how long the drug will remain in the body, and at what point it might stop the therapeutic range, which is why some dosing is over several ingestion cycles verses an extended release.

I highly recommend the book "A Primer of Drug Action" by Julien, Adcokat and Comaty (2011) for further reading. It describes a lot of medications and drugs. There are a variety of understandings of these medications and drugs currently.
> 1 votes

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Tags: abnormal-psychology, clinical-psychology, meditation
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# Question
Title: Is there a cognitive bias which describes expert communities' overestimation of their potential impact?
I was recently trying to argue that the Democratic National Committee's efforts to undermine the Bernie Sanders campaign were probably ineffective, and that those who attempted to do so probably suffered from a specific cognitive bias. Namely, due to their presence in the "political operative" nexus, they tended to overestimate, in general, the impact that political operations have on elections, swaying public opinion, etc.

I wonder whether social scientists have observed that, in general, experts overestimate their ability to make an impact, because they put the system they belong to on a pedestal. Has such a cognitive bias ever been discussed in the literature? Is there a name for it?

# Answer
> 2 votes
This sounds like a mix of biases "due to the effectiveness of a search set", "the illusion of validity" and "biases of imaginability". See judgement under uncertainty \[Science, New Series, Vol. 185, No. 4157. (Sep. 27, 1974), pp. 1124-1131.\].

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Tags: cognitive-psychology, bias
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# Question
Title: Differential diagnosis for shortness of breath from anxiety
Unexplained or difficult to explain shortness of breath seems to be blamed on anxiety very frequently despite lack of diagnostic evidence, especially in individuals with psychiatric conditions. This is not helpful to people that experience shortness of breath as a side effect of medication or from other causes that have not been identified.

How can one make sure that the diagnosis (and vast symptoms) of anxiety isn't being applied too liberally and that the patient receives the best possible diagnosis/care (especially when there are concurrent psychiatric conditions)?

# Answer
> 0 votes
I think that if you combine the reading of the DSM with a pharmaceutical book such as the BNF you will get the desired results when you know what your client is prescribed.

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Tags: psychiatry
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# Question
Title: Significance of 4 stimulus cards in the Wisconsin Card Sorting Test?
I've reviewed the papers by Grant, D. A., & Berg, E. (1948) and Fey, E. T. (1951).

These papers from what I was able to find, lay out the basis of the Wisconsin Card Sorting Test (WCST). There are three possible rules for sorting the cards; color, shape, or count. I am curious why the WCST places 4 stimulus cards in front of the patient when 3 carefully chosen cards would be sufficient. With 4 cards it seems that unless the examiner makes special preparations, there might be occasions when there is more than 1 correct stimulus card to choose, or during a transition from certain rule to the next the patient may make an incorrect guess and won't be able to tell which rule to eliminate.

Can anyone explain why there has to be 4 stimulus cards? Could I run an equally effective WCST with 3 stimulus cards?

<sub> Grant, D. A., & Berg, E. (1948). A behavioral analysis of degree of reinforcement and ease of shifting to new responses in a Weigl-type card-sorting problem. Journal of experimental psychology, 38(4), 404.
Fey, E. T. (1951). The performance of young schizophrenics and young normals on the Wisconsin Card Sorting Test. Journal of consulting psychology, 15(4), 311.
</sub>

# Answer
I cannot tell you why they chose four cards, but I do know that it is perfectly fine to use three, (e.g. Niv and colleagues, 2015).

To give you more info on why the WCST is used in the study by Niv. The study wanted to see how you could best model learning (and relearning) multidimensional information, to be able to better understand how people make sense of the multidimensional information provided by the real world. Therefore, they had participants perform the WCST with three cards. Multiple reinforcement learning algorithms were then fitted to the behavioral data, and they found that a reinforcement learning model that includes decay (as to model memory decay) was best able to do so.

I believe it would have been perfectly fine to have used four cards in that study as well. It would make it more difficult to learn on which dimension to focus, which would probably also be modeled.

There are also variations of the WCST (e.g. Catherwood and colleagues, 2014). In that study they instead of took apart four dimensions and showed a 2x2 matrix with each unit depicting a different dimension.

## In short

Depending on the goal of your experiment, you can decide how you would like to use the WCST specifically.
> 4 votes

# Answer
I wanted to report further findings in my search for the answer to this question. I will not accept this as the answer but I think anyone else who looks into this issue may find this information useful.

I obtained the original paper by Berg (1) published in 1948 in the journal of general psychology. The paper makes no explicit mention of why 4 stimulus cards are shown. Perhaps the choice was to follow previous methods in similar tests such as the Goldstein-Sheerer cube test (2).

The results of the Berg paper, a *post-hoc* style analysis, grouped the participants into 3 groups based on quantitative performance (A,B, and C). Group A quickly determined the rules of the test and performed well on the remainder of the test. Group B took longer and verbally reported trying many hypotheses of the rules before discovering there were 3 rules to choose from. Group C had no idea what was going on, some subjects perseverated 100 trials with their own incorrect rule.

I therefore speculate that if there were only 3 stimulus cards that group B would be somewhat eliminated. Subjects who could determine the rules would get there faster by elimination since there could only be 1 correct stimulus card at a time. One virtue then, of having 4 cards, is to parse out subjects who have a more keen ability to "think/shift" which could be more useful/powerful if the goal of the test is to quantify shifting ability.

Furthermore, I took the online test located here and found 18 out of 60 trials where there was more than 1 matching possibility yet I was able to succeed at the test because I was able to track which rule I had been using.

I agree with Robin Kramer that the number of stimulus cards can be altered depending on the purpose of the test.

> 1. "A simple objective technique for measuring flexibility in thinking." Berg, A, 1948, Journal of General Psychology, Vol 39, 15-22.
> 2. "Abstract and concrete behavior: An experimental study with special tests." Goldstein, K., Scheerer, M., 1941, Psychology Monologues, Vol 53, 1-151
> 1 votes

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Tags: test, categorisation, frontal-lobes
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# Question
Title: What's the term in psychology for the way people think of concepts using examples?
I learned about this but forget its name. The idea is that when people hear a word or think of a concept they tend to come up with certain examples that fit the idea more than others. For example, if people think of birds, they tend to think of sparrows or seagulls, not penguins, even though penguins fit the definition of bird perfectly. If people are told to imagine a chair, they tend to think of one with 4 legs, probably made of wood, not something like a movie theater chair. What's the name for this?

# Answer
> 5 votes
You are talking about Prototype Theory:

> ... any given concept in any given language has a real world example that best represents this concept. For example: when asked to give an example of the concept furniture, a couch is more frequently cited than, say, a wardrobe.

Specifically, the "graded categorization" (degree) property of prototypes:

> For example, robins were seen as being "birdier" than ostriches ...

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This contrasts with Exemplar Theory, which proposes that categories are based on all examples rather than one or a few:

> For example, the model proposes that people create the “bird” category by maintaining in their memory a collection of all the birds they have experienced: sparrows, robins, ostriches, penguins, etc. If a new stimulus is similar enough to some of these stored bird examples, the person categorizes the stimulus in the “bird” category.

Other theories on categorization (or how a Concept is structured in the mind) include Essentialism, Theory-theory, and Bayesian Inference.

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Tags: terminology
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# Question
Title: What's the difference between computational neuroscience and systems neuroscience?
I'm an engineer, interested in mental machinery, to imitate cognitive capabilities of the human mind into primitive artificial models. In this case, cognitive neuroscience (CogN) is something, apparently, relevant and important field.

But I have no clear idea about the differences between computational neuroscience (CompN) and systems neuroscience (SysN) ***and their relevance to my target***. In my view, these two topics are very similar (if not the same!), because one need to analyze the brain and its systematic functionality by computational approaches. Furthermore, it is inevitable to consider system-driven perspective to be able to present computational interpretation for neural systems.

1. **So, what is the subtle difference between SysN and CompN?**
2. **Which one should be taken into account within (in coordination with CogN) to studying of the mental functionality of the brain?**

Thanks

EDIT: Someone else's answer to the first question, does which sound like a seminal viewpoint:

> I feel the question is ill-posed. Don’t pick a “field” to study. Pick a problem to study. Based on the problem selected one or another field may be more relevant for your work, but it is unlikely that any interesting question about cognition will fall wholly within the domain of any one classically defined area of neuroscience.

# Answer
Systems neuroscience studies systems, such as the visual sensory system - from the light (input) to the cortical representation. Systems neuroscience generally implies an integrated approach that includes *fundamental* or *basic neuroscience* \- the study of cellular and molecular functions of the nervous system(s) - and typically borders to behavioral or cognitive neuroscience.

Whereas *cognitive neuroscience* aims to explain the "biology of the mind" - for example, how is memory realized in the brain - systems neuroscience aims to explain how the brain works - for example, how does the brain give rise to vision.

*Computational neuroscience* is fundamentally a mathematical discipline that is realized using computers. It is used to both simulate (*theoretical neuroscience*) and validate *in vivo* and *in vitro* findings *in silico*. It includes the abstraction of general laws based (more or less) on empirical data. Generally, initial parameters are based on findings from basic neuroscience, which enables biophysically realistic models based on the functionality of neurons to be implemented. However, less realistic simplified models are often used to model neural networks that have an applied AI task. However, these models border to computer science and in particular AI and machine learning.

Neuroscience is a large field and there is a strong need to bridge the different disciplines that contribute to the science, not only through computational neuroscience, but also through neuroinformatics:

> The exponential growth of the data produced in neuroscience mean that computational approaches are fundamental to make sense of this information, including theoretical modelling and methods for large scale data analysis/integration that are capable of handling and comparing data generated over such diverse timescales (e.g. synaptic versus genetic changes). As such, quantitative theoretical neuroscience must be gradually integrated with mainstream experimental neuroscience. —European Brain Council Consensus Statement - March 2016

## In response to comment

"Basic neuroscience" requires an *invasive* study of neurons in order to study the molecular mechanisms of the cell - on the most basic level. That is why mostly animals are used in this type of study. (However, neuroanatomists also study human post-mortem brains, and molecular imaging can be used in humans, but on a different level of explanation - a whole-brain perspective - with less specificity of the causal mechanisms on the cellular level.) *Molecular neuroscience* studies, for example, the properties of different types of calcium channels. A famous computational model is the Hodgkin-Huxley model that is based on the study of aplysia. In this regard, basic neuroscience informs computational models that are bottom-up, but there are also top-down models that rely on pure psychology, and a range of models in-between.

*N.B. I would be careful to use the term "exploratory", because this implies that the science proceeds without a hypothesis. That is rarely the case in the natural sciences, but some of the pioneering work is indeed exploratory.*

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I am a PhD student in Neuroscience working with humans. Some of my colleagues work with animals or cell cultures. One of my collaborators works in computational neuroscience and we are currently working on a new model together that we might be able to update based on the empirical findings in my lab. This type of collaboration is important, because the computational model "knows" more basic science, than I could possibly study in humans. That is why we can use computational models to test the limits of our findings - to test if our models of cognition are compatible with biophysical models, which are informed by principles derived from animal studies.
> 1 votes

# Answer
I think you have sliced off tiny bits of both systems and computational neuroscience to the extent that you now think they are the same. In fact, they are massively different. The is no *need to analyze the brain and its systematic functionality by computational approaches*; there are lots of non-computational approaches to study the brain and its systematic functionality. Computational neuroscience requires computation, but can be applied on a variety of scales (e.g., single neuron or system). System neuroscience only applies to systems, but can be done with a variety of techniques (e.g., computational, intercellular recordings, and fMRI).

I am not entirely sure what it means to study the "mental functionality of the brain", but my guess is it requires systems neuroscience. There is no inherent reason that you would need to do this with a computational approach. That said, it sounds like you want to take a computational approach.
> 0 votes

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Tags: cognitive-neuroscience, computational-modeling
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# Question
Title: Isolating stable EEG data across all channels in EEGLAB
I'm working on some EEG data we collected using the Emotiv Epoc headset using 14 channel sensors.

I need to isolate chunks of data where all 14 channels are stable (non-noisy) for a given length of time (e.g. 5 seconds). I've written a MATLAB script for this, such that I calculate the standard deviation of each channel and pass an analysis window over the data, comparing the difference between maximum and minimum values in the window to this standard deviation (i.e. where maximum - minimum is less than the standard deviation \[or 3-5 standard deviations\], I treat that window as stable).

Based on this criteria, I am having some success in finding 5 second long segments but am worried this data may not be reliable (or not as stable/artefact free as desired).

Are there any better ways of performing this analysis? Even better, are there any functions built into EEGLAB for this very purpose?

**Further info:**

I've selected only the relevant channels and can now look through my EEG data files.

I am no neuroscience expert, actually I'm rather new to this sort of analysis, so apologies if this question is overly basic or off-point.

**EDIT**

We collected our data in a museum environment (very noisy in many ways), with participants sitting as still as possible for 2-minute sessions at a go. For this reason, there is a high likelihood of artefacts being found in the data due to movement, the environment and possibly even inaccuracies from the device itself (since we went through a rather large number of participants, cleaning and charging the headsets in between trials).

From what I've discussed with the team, I've been told that removing artefacts wouldn't solve the issue (though admittedly I'm no expert as to why this would be).

For clarity, the data we've collected looks similar to the plot below.

And we're looking for a minimum of 5 seconds of stable data, closer to the plot below.

Also, I know this data selection can be done manually using pop\_eegplot, however since we have close to 300 data files I'm looking to automate this (and hopefully get more reliable selections).

# Answer
> 0 votes
You could try to use approaches that are similar to measure the strength (and delay) of a P3 response in ERP data. There are many ways described to measure the P3 responses (or any other response you are interested in) in the book of Luck: An introduction to the event related potential technique. These include:

* Maximum value (within a time frame; sort of what you are doing)
* Mean peak value (averaged over a time frame)
* Area of the response ($amplitude * time$)

I am probably missing a few, so you might want to check out that book. These may provide more reliable results than solely looking at max-min differences.

# Answer
> 1 votes
In this conference paper they propose an algorithm that roughly goes as follows (if you can't access it, just add "sci-hub.bz" after ".org" in the url and it redirects you directly to the pdf) :

* Divide channels into four groups: 1) frontal, 2) central, 3) temporal and 4) parietal+occipital.
* For each group take three signals: 1) the raw signal, 2) the alpha band(8-12Hz, using a 3rd order butterworth band-pass filter) and 3) the beta band(13-35Hz).
* For each group and each signal calculate the four metrics: 1) max amplitude, 2) standard deviation, 3) kurtosis and 4) skewness. For the frequency band signals they also take the mean power and the standard deviation of the power.

They then go on and find optimal thresholds for each metric, group, and signal by using a differential evolution algorithm on training data, so unfortunately it's not immediately applicable for you. As I see it, you have at least two options here:

1. Create 5 seconds long epochs of your data and label a lot of them. Use that data to learn optimal thresholds (unfortunately they don't give any details on how to do that, so you would have to figure that out yourself). This would obviously take a lot of effort but at the end you can be quite confident about your classification.
2. Just try some value ranges for the different metrics, you can orient yourself on the values they found in the paper (you have to read them from the plots though). Check the resulting classifications. Pick the threshold values that give the "best" results by inspections. This is not as systematic as the first option but might fit your needs already. For example if you just want to avoid to have segments that were falsely classified as "clean" you might just go for very conservative/safe threshold values. There is a **big danger** here though, that you will get lost in an endless loop of "maybe if I adjust this threshold a bit more" and will never stop exploring. To help with that, you might also reduce the number of metrics, groups or signals.

# Answer
> 0 votes
## Short answer

This answer is not on how to find clean data. Instead, I would like to argue that you can clean your data.

## Long answer

> We collected our data in a museum environment (very noisy in many ways), with participants sitting as still as possible for 2-minute sessions at a go. For this reason, there is a high likelihood of art\[i\]facts being found in the data due to movement, the environment and possibly even inaccuracies from the device itself.

This is indeed true. The Emotiv Epoc has shown to not be the best EEG headset and introduces a lot of noise (e.g. Ries et al., 2014). In this study, where they used an odd-ball paradigm (a highly controlled lab experiment), the authors found that significantly more trials had to be removed, compared to medical grade EEG (BioSemi) and another wearable EEG headset (B-Alert X10).

> From what I've discussed with the team, I've been told that removing artefacts wouldn't solve the issue

It is true that removing muscle artifacts (they were sitting still right?) and system noise will not be very helpful. The data will be contaminated throughout the task, and removing that would likely also remove some actual data. It may be interesting to investigate at what frequency the system adds noise. You could do a measurement with the system while it's not equipped to the head, and then calculate the frequency spectrum with an FFT. This will give you an indication of how your actual data was affected.

You can remove ocular artifacts though. As you showed in the picture, there is only one clear peak in that five second period. That particular patterns is a clear eye blink. Another EOG artifact is an eye movement, which can be seen in the picture below as the jumps in data in the top two channels (between 3 and 3.5 seconds).Both artifacts can easily and rather safely be removed due to their distinct patterns. For this I always use an independent component analysis (ICA; Makeig et al., 1996). This is also explained by Delorme and Makeig (2004) for EEGLab specifically (and here is a tutorial that explains it with FieldTrip).

**What would that mean for your data?**
Whenever you got rid of the EOG artifacts, your data should be pretty clean. Then, you do not need to search for clean periods but you can select the same (or a random) period of time for each participant. However, if you really do not want to clean your data, this answer doesn't help you.

# Answer
> 0 votes
For automation, you need to write a MATLAB script that controls EEGLAB. One option is to use the Automatic Artifact Removal toolbox, which you can find a link to here.

Generally, min, max, abs(max-min) criteria suffice to mark the artifactual events, followed by artifact rejection. However, line noise and environmental noise must be dealt with separately. The influence of eye movements can also be removed - either using ICA, which would be a timely process for 300 data sets (assuming you do not have have access to a MATLAB computer cluster), or computing virtual EOG channels and excluding data based on some criterion for those peaks. Compute the channel Af4-Af3 for horizontal eye movements and F7-F3 for vertical. Tweak the parameters for a single noisy data set first. If that works, batch process the files with the same criteria. I would start with Steven Luck's criteria.

Artefacts will go away once you start averaging across trials because of common mode rejection, but they can be influential if not dealt with.

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Tags: eeg
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# Question
Title: Human brain v/s computer: speed comparison?
We can't compute (speaking of some of the functions a computer can perform ) as fast as a computer. Where does this shortcoming stem from- working memory or clock frequency perhaps comparable to the firing frequency of neurons- in this analogy? I have come across that the conscious mind can hold only about 40 bits(or other similar, small numbers) at a time. So what all could I accomplish given I had access to say 6 GB of RAM? Note: Please consider this analogy even if it's remotely applicable.

# Answer
> 2 votes
Doing this sort of comparison is very difficult.

First, the brain is not digital by any stretch of the imagination, it is highly analog. Computers, on the other hand, are digital (binary, specifically). So doing a calculation measurement on a brain is hard to begin with.

Second, the way they handle tasks is very different. Computers are designed to carry out individual, complex tasks in a stepwise manner. Brains, on the other hand, are designed to do an enormous number of simpler tasks in parallel. So an individual task for a brain might be slower, but that is because the brain is doing a lot of other stuff at the same time, and only a small portion of the total "processing power" is available to individual tasks.

Third, their architectures are organized to do completely different tasks. Modern computers are largely designed to do mathematical calculations on binary numbers, integers, and/or floating-point numbers. Processors are largely designed around doing these sorts of calculations (and moving memory around). Brains, on the other hand, are pretty bad at those sorts of calculations, and don't seem to have anything equivalent to moving blocks of memory around (the brain has no such thing as "RAM"). Brains are much better at fuzzy (non-binary) operations like pattern matching, things that computers are really bad at.

So it isn't that computers are faster than brains, they aren't. It is that brains and computers are optimized for different sorts of tasks, and they do those tasks in different ways.

# Answer
> 1 votes
Neurons have a refractory period, meaning that they are rate limited (see Kandel et al., Principles of Neural Science). As the demand on working memory increases, more neurons need to be working in synchrony (Vogel & Luck, 2013 ...). The human brain is characterized by gyri, compared to the flat surface of the mouse brain. This evolutionary adaption is believed to reflect a biological strategy to maximize the brain use inside the skull. However, brain size does not correlate with intelligence. The density of white matter fibers, however, sometimes do. An increase of grey matter also reflects knowledge, in taxi drivers for example. (However, it is also known that more efficient processing requires less neurons. See the documentary on Vanessa Mae for an example).

If a human being had 6 GB RAM, you would have to take into account the cycle speed, swap speed, etc. This would reflect an autistic alien being capable of rendering roughly 12 hours of music all at once.

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Tags: measurement, theoretical-neuroscience
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# Question
Title: What is the status of traits theory in personality psychology?
Currently, what is the status of traits theory in personality psychology? Is it still a satisfactory theoretical framework to which to refer? What about its personality tests? Could you support your answer with recent scientific literature, please?

# Answer
This question is quite vague. The trait perspective is probably the most actively researched perspective in personality research. Many thousands of papers are published each year using trait-based measures. And there is a lot of active debate about theoretical and measurement issues.
> 1 votes

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Tags: personality
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# Question
Title: Generate fMRI from neurotransmitter consumption
As mentioned in this answer, it's possible to generate an fMRI BOLD signal from neurotransmitter consumption. What equation would be appropriate for this use?

# Answer
> 2 votes
The simplest equation for getting a BOLD signal from neurotransmitter that I could find was in "Tracing Problem Solving in Real Time: fMRI Analysis of the Subject-paced Tower of Hanoi", which itself references many other publications where it was used:

$$H(t)= m \times(t/s)^a\times e^{-(t/s)}$$

The parameters $s$, $a$ and $m$ don't have an explicit meaning. Heuristically, from the text:

> $m$ is the magnitude of the response and $s$ is a time scale. The function peaks at time $a \times s$. The parameter a determines the shape of the function such that the larger $a$ is the more narrowly the function will be distributed around its peak.

So it seems you have to fit it to some previous data in the area you're trying to generate data from before it can be used.

# Answer
> 2 votes
It is not clear what neurotransmitter you are interested in, but one model that relates the PET ligand affinity to the cerebral blood volume (CBV) from fMRI looks like this:

Source: Neurovascular coupling to D2/D3 dopamine receptor occupancy using simultaneous PET/functional MRI

You can find several studies, which try to relate neurotransmitters with oxygen consumption. Google made the following suggestions to me:

In addition to PET, of special interest is the technique MRS using the same type of scanner that is used for fMRI:

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Tags: theoretical-neuroscience, fmri
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# Question
Title: Can you learn a skill by observing someone else?
For instance, does watching an artist draw improve your drawing skill, even if you're not drawing along with them?

# Answer
> 3 votes
Watching others perform a skill serves as both instruction and visualization practice. The instruction can provide the beginner with a wealth of information that they lack, when starting a skill. It provides the experienced practitioner with details of technique that informs their growth.

How productive watching can be sometimes depends upon previous experience. For example, in the medical profession there is a phrase, "Watch one. Do one. Teach one." Which indicates that the practitioner should observe a technique once, do the technique once, and then teach it to someone else, once. This seems frightening, at first glance, since I certainly do not want to be someone's "do one" when I am lying on a surgery table.

However, the actual context of this learning method matters. Generally, what the practitioner is learning is some small variant of a skill they have already mastered. For example, if they already know a wide array of stitches for closing wounds, they may be learning a variant of one of these stitches. In this case, seeing the technique performed slowly once is sufficient. Then they practice the stitch by "doing one", often while being observed. Finally, they teach the technique to someone. This serves to reinforce their new knowledge, because to teach someone else something requires that you think about the subject carefully, which in turn aids in mastery.

Such a system of learning by watching breaks down, if the context of previous knowledge is omitted.

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Tags: perception, learning, motor, perceptual-learning
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# Question
Title: Why is Potassium(K) important to neurology & the brain?
When researching the pharmacological mechanisms of action and interactions that various psychotropic drugs, poisons, neurotoxins, etc. have on the brain:

I frequently see off-hand references to the element ***Potassium(K);*** in the context of matters concerning neurons, neurotransmitters, neurotransmission, and so on.

Why is ***Potassium(K)*** relevant/significant/important to neurology & the brain?

# Answer
The main cell of the brain is the neuron. The neuron has a semipermeable membrane that under specific circumstances lets potassium through. Another common cell is the glia cell, which only has potassium channels. Potassium, K+, has a positive charge and it can pass across the membrane at specific channels, depending on their state (open/closed). The channels are ion specific as the amino acids that make up the channels (proteins) have different charges and configurations.

Different membrane *ion channels* have different roles. K+ is mainly found in the cytoplasm during resting state with an equilibrium potential of -75mV. In the typical neuron model, this potential is larger than that of Na+ or Cl-.

Ions seek out an equilibrium where they do not have to move because positive and negative charges repel each other. However, the cell is determined to manage this laziness and to avoid a stand-still, it has a negative potential.

When K+ exits the cell, the relationship between positive and negative ions changes, leading to an increasing voltage difference between the inner cytoplasmic and the outer extracellular ions. The negativity in the cell increases and two things happen: a chemical driving force from K+ and an electrical driving force - resulting from the voltage difference. As the K+ exits the cell, neighboring channels increasingly adopt the same pattern and this gives rise to a domino effect along the cell membrane, which travels through the axon. As this switch from -/+ to +/- occurs as K+ passes the membrane the outer charges ++++ switch to ----. This results in a voltage +- that grows along the axis ++--, +++---, ++++----, but this is mediated by Cl-, resulting in a cycling of the potential - and it moves:

------, +-----, ++----, +++---, +++++-, -+++++, --++++, ---+++, ----+, ------

(Kandel et al., Principles of Neural Science, 5th ed., p.126-129, p.144)

The potassium drives the action potential and that is why neurons can "talk to each other" and signals can reach their destination. This is why potassium is important for the nervous system.

Above, +++--- implies the outer charge and thus the cell membrane has the voltage:

```
+ + + - - -
- - - + + +

```
> 4 votes

# Answer
Without Potassium (K), no chemicals move.

The Central Nervous System is comprised of a variety of chemicals, electrical signals and neurotransmitters to send a variety of signals through the brain and a variety of receptors of the nervous system. If you want to send a signal of neurotransmitters (medications/ or other chemicals found in your list), there must be proper voltage to move the chemicals around.

The Potassium (K) and Sodium (Na) interact with their respective ion channels to depolarize the cell from -70mV (theoretical resting) to about +55mV (about when movement of neurotransmitters happens). The cells attempt to create an equilibrium, but are in a feedback loop of chemical and electrical interactions.

Luo's Principles of Neurobiology (2015) is a good reference, and there are a variety of other human biology texts that could also illustrate the examples of how these chemicals interact. The http://www.mindcreators.com/neuronbasics.htm also seems to be a good source of visuals.
> 1 votes

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Tags: neuroscience, cognitive-neuroscience, neurophysiology, psychopharmacology, electrophysiology
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# Question
Title: Models of barriers to "Flow" (being in "the zone")
This Wikipedia article is an excellent overview to the concept of Flow.

The problem is, from personal experience, in one specific area, I think it's incomplete. To quote:

> Schaffer (2013) proposed 7 flow conditions:
>
> * Knowing what to do
> * Knowing how to do it
> * Knowing how well you are doing
> * Knowing where to go (if navigation is involved)
> * High perceived challenges
> * High perceived skills
> * Freedom from distractions\[22\]

And there are times when I can check the above off but still be feeling unable to get in the zone. My best guess is the weak point is either:

* distractions - it's a broad term, and feeling under pressure, even if completely self imposed, comes under that category.
* Knowing how to do it. If there are several options, and you know how you might do each, but can't decide which might be best, it becomes an issue, even if there is no obvious difference.

Are there any alternative models which explore possible barriers in more detail? Or any concepts such supplement flow theory to give further preconditions for flow? Stating the obvious perhaps, nearly any aspect of a person's general state of mind can be a barrier. Stress, even on unrelated tasks, is an obvious one. Is that already coversed in the above model? It would hamper decision making (knowing how you're going to do it), even though you do know how to do it. Perhaps it also counts as a distraction?

One last thought: perhaps, checking off the above, but feeling unable to achieve flow is itself a sign of incorrect cognition, since one or more points have been incorrectly assessed. (Assuming the model is correct and complete).

# Answer
The model is mindfulness.

There are three options:

* You can focus on the negative
* You can focus on the positive
* You can focus
> 0 votes

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Tags: performance, concentration
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# Question
Title: what does “dominants” mean in psychology
I am reading the book "The Psychedelic Experience". In the following two sentences word "dominants" is used

```
1. ...world of psychic “dominants” from which the ego originally emancipated itself with enormous effort

2. ...and the terrifying dream evoked by karma and played out by the unconscious “dominants” begins

```

What does "dominants" mean in these sentences. I googled if "dominants" has any special meaning in psychology but couldn't find any results.

# Answer
> 1 votes
I have just been doing some research on this piece of writing and I wonder if anyone really should take heed to what is written. The reason is that the writing seems to be an attempt on a

> psychedelic version of the Tibetan Book of the Dead (source)

It is not something I personally would take any notice of, however, from my understanding after reading the above source, this writing is talking about "transcendence" and the "pre-mortem-death-rebirth experience" through the stages of ego-loss, hallucinations and "reentry" created by ingestion of psychedelic drugs such as LSD, psilocybin, mescaline, DMT, etc.

> Of course, the drug dose does not produce the transcendent experience. It merely acts as a chemical key - it opens the mind, frees the nervous system of its ordinary patterns and structures.

Where it says

> ...the terrifying dream evoked by karma and played out by the unconscious "dominants" begins.

it seems to be talking about the "second stage" called the Chonyid state (hallucination state) where you have "reached your goal" of ego-loss in the Fruedian sense and now you are allowing your thoughts to come to play as though they are reality as the preceding part of the sentence says

> The "thought-forms" appear as realities, fantasy takes on real form

This is the effect of taking these psychedelic drugs. The ego is diminished and therefore you lose touch with reality, norms and rules.

I believe the "dominants" in this writing is referring to the dominant thoughts.

edit - *for further info*

I am in the middle of learning about analytical psychology and for the authors to refer to Carl Jung as someone who was interested in the Tibetan Book of the Dead (Bardo Thodol) and that he would possibly advocate their "psychedelic version" interested me.

Carl Jung apparently suffered from a form of psychosis and as a result, he suffered with visions and hallucinations.

> Jung spent time in his study inducing the visions and hallucinations. He did this not through the use of any kind of drug, apparently, but instead through his own personal methods that allowed his unconscious mind to become totally open and flowing forth. (source)

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Tags: terminology
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title: What is the limit of human memory?

text:
# Question
Title: What is the limit of human memory?
I am currently a high school student and have grown curious at what the limitation of memory storage in the brain might be in humans.

**Information is coded genetically and stored in the brain, but is there a limit to how much information a person can retain without forgetting?**

In high school I have taken a broad courses in biology, chemistry, physics, calculus and more. I wonder if my desire to learn and keep moving forward will be hindered mentally by the intrinsic aspects of memory (if they do exist)?

# Answer
> -3 votes
http://www.scientificamerican.com/article/what-is-the-memory-capacity/

https://www.quora.com/Is-there-a-physical-limit-to-human-memory-If-yes-can-it-or-has-it-been-measured

It's said that you store everything or nearly everything you experience in your subconscious mind.

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Tags: memory
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# Question
Title: Reading and understanding difficult material
I am not an university graduate but I have a passion for learning. I want to learn computer science and I keep on searching some good reference material. Recently I found some lecture notes on TOC of a well known teacher although he has explained things in detail but I am having hard time to grasp the material. One of the reason being is that they assume that you have a good mathematical foundation and other is you have the TA and professor to help when needed.

Now, for the first reason I have a good mathematical background but sometimes it may not suffice to the expectation. Second, I am a self learner hence I don't have the luxury to clear my doubts and ask questions.

What I am doing is try to study the material normally 2-3 pages and re-read it until it makes sense or I get frustrated, next day I try to feel positive and try again, I am making progress but it feels slow.

The questions are:

1. I will be able to change my brain's wiring by such constant effort?
2. How to judge that I know the material? by doing exercises? but I don't have solution?
3. How to be motivated in such situations?

# Answer
1. Definetly yes! Even if you feel frustrated at the beginning, thinking and learning about a topic has an impact on your brain. See for example Robert Greenes book "Mastery" (https://en.wikipedia.org/wiki/Mastery\_(book)), where he describes the lives of various geniuses like Leonardo da Vinci and Charles Darwin. They all spent a lot of time becoming masters of their field.
2. Theoretical Computer Science is a very abstrct topic. I would recomend you to participate in some online class. See https://www.coursera.org/courses?languages=en&query=computer+science for example. There you can do excercises that get peer reviewed by others. So you know if you did well or not.
3. Increase you motivation by:

* Learning in groups like on Coursera.
    * Setting clear goals. What do you want to achieve? Get a better job? Write it down. Hang it on the wall.
    * Taking small steps. If you take steps that are too big, you might feel overwhelmed.
> 2 votes

# Answer
Before I attempt to answer your questions, can I suggest you look at joining the computer science group on stack exchange. Even though you have no TA or instructor, use of groups like this obviously gove you the benefit of learning through peers.

Now to your questions..

> I will be able to change my brain's wiring by such constant effort?

Learning rewires your brain. This article may help to explain that. For more, you could look at these articles

> How to judge that I know the material? by doing exercises? but I don't have solution?

That can be a difficult one because as you may not be following a structured curriculum you will not be able to formulate a theory test. However, could you judge understanding by learning what you need to know and testing your theory with some kind of practical test?

> How to be motivated in such situations?

There are a few websites and forums out there on studying methods etc. and this page gives ideas on motivation for studying
> 1 votes

# Answer
I have never found a better learning method than to put the book down.

As a great Philosopher of our Age once said "a man has to know his limitations" or more specifically...that he is limited, just a man.
> 0 votes

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Tags: cognitive-psychology, learning, motivation
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# Question
Title: What techniques are being used here to influence the subject to pick a certain outcome?
The question is about this video.

**Summary of the Video:** (can skip if you watched it)

The only audio is "elevator music." There is a man who communicates only with written orange signs. He asks the viewers to quickly perform some easy arithmetic calculations, and he shows the answer to each one after a few seconds:

$5+3 \ \ = 8$

$9+2 \ \ =11$

$10-6=4$

Then, he asks the viewer to quickly pick a number between $5$ and $12$. At this point, I suddenly felt a sense of urgency, and rapidly picked $7$; it was the only number I could think of in that second. Of course at the end of the video, the man guessed that the subject picked $7$.

**Question:**

How does this video influence the viewer to pick $7$? More generally, what techniques do these types of videos employ to try to manipulate the subject into chosing a certain outcome?

---

I tried to look for certain patterns in the calculations and I found a diagonal symmetry, but I'm not sure if it's relevant:

$\color {red}{\text{odd}} \ \ + \color {red}{\text{odd}}$

$\color {red}{\text{odd}} \ \ + \color {blue}{\text{even}}$

$\color {blue}{\text{even}} \ + \color {blue}{\text{even}}$

I've also noticed that the average of the $3$ results is $\dfrac {8+11+4}{3} = 7. \overline {6}$

# Answer
Priming is a phenomenon where an exposure to a stimulus affect/influences response to another stimulus. It is however, a broad definition which may or may not fully explains what actually happened in the video.

For what's it worth, I notice that number 7 was the only number (between 0-9) that didn't appear at all in any of the arithmetic calculations, answers or questions. But I can't say that I understand how this could influence subject's choice.
> 1 votes

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Tags: cognitive-psychology, attention
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