# Question
Title: Understanding the concept behind d-prime
I know that sensitivity (d') is typically calculated as follows:

d' = z(Hit Rates) - z (False Alarm Rates)

I understand this as the idea is to standardize both distributions, and to then calculate the z-score, which allows to calculate a distance within the same scale so to say.

What is however very confusing to me is the visualization of the process. I am using the following plots from these slides:

My questions are as follows:

(1) As in the plot above, d' is *always* depicted as the difference of the means of the two distributions (of signal and noise, for instance). Say however that I find in my data that the Hit rate (or Hit probability) is 0.8 - I would think that now, I would need to find z(Hit = 0.8), would this not be to the right of the mean:

Is this correct?

(2) In addition, I am am uncertain about the arrows associated with Z(CR) and Z(H) on panel A above.

For one, in my opinion, CR includes the entire area before the criterion. The arrow, however, associates Z(CR) with only the distance mean-criterion - why?

Then, if Z(X) refers to the cumulative probability density of variable X, Z(X) should be the entire density up to X. In the case of Z(CR) in panel A,however, it seems that it is only the part from the mean of the noise distribution to criterion. So what does then the Z(..) notation mean in this context?

# Answer
> 2 votes
First lets write down some math for the above figures assuming Gaussian distributions with means $\mu\_{n}$ and $\mu\_{s}$ both with a standard deviation of unity. In this case the probability of a detection is

$$P\_D=1/(\sqrt{2\pi})\int\_{c}^{\infty}e^{-(x-\mu\_{s})^2/2}dx$$

and the probability of a false alarm is

$$P\_F=1/(\sqrt{2\pi})\int\_{c}^{\infty}e^{-(x-\mu\_{n})^2/2}dx$$

and the normal deviates are

$$Z\_D=\Phi^\prime(P\_D)$$

and

$$Z\_F=\Phi^\prime(P\_F)$$

where $\Phi^\prime(x)$ is the inverse of $\Phi(x)$

$$\Phi(a)=1/(\sqrt{2\pi})\int\_{-\infty}^{a}e^{-x^2/2}dx.$$

We also need to note that

$$1/(\sqrt{2\pi})\int\_{-\infty}^{c}e^{-(x)^2/2}dx+1/(\sqrt{2\pi})\int\_{c}^{\infty}e^{-(x)^2/2}dx=1$$

and that

$$\Phi(-x) = 1-\Phi(x).$$

Now using integration by substitution on $P\_D$ and the above equalities gives us

$$P\_D=1/(\sqrt{2\pi})\int\_{c-\mu\_{s}}^{\infty}e^{-(x)^2/2}dx=1-1/(\sqrt{2\pi})\int\_{-\infty}^{c-\mu\_{s}}e^{-(x)^2/2}dx=1-\Phi(c-\mu\_{s})=\Phi(\mu\_{s}-c).$$

You can play the same mathematical games and get that $P\_F=\Phi(\mu\_{n}-c)$ or that $Z\_D=\mu\_{s}-c$ and $Z\_{CR}=c-\mu\_{n}$ (this one is a little trickier ...).

Now on to your questions

> (1) As in the plot above, d' is always depicted as the difference of the means of the two distributions (of signal and noise, for instance). Say however that I find in my data that the Hit rate (or Hit probability) is 0.8 - I would think that now, I would need to find z(Hit = 0.8), would this not be to the right of the mean:

This depends on what the means are. If the signal distribution has a mean of $-100\sigma$, then $Z\_{hit}$ will likely be to the right of the mean, but if the signal distribution mean is $100\sigma$ it will likely be to the left.

> In addition, I am am uncertain about the arrows associated with Z(CR) and Z(H) on panel A above.
>
> For one, in my opinion, CR includes the entire area before the criterion. The arrow, however, associates Z(CR) with only the distance mean-criterion - why?

This is a direct result of the magic of the math above.

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Tags: psychophysics, signal-detection
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# Question
Title: Is there any significance to the way Trump spreads his hand from each other?
Is there any significance on how President Trump constantly spreads apart from each other his hands while talking?
I postulate that this falls under some sort of sub-conscious (or conscious) body language message. Though, I can’t put my finger on it, my speculation ranges from where it is at his disadvantage to those watching him.

Specifically, when I saw ***this video*** I was awakened to ask this question. The way he conducts himself there seems to be a hyper-version of whatever it normally means.

# Answer
> 3 votes
**Short answer**
The open palms are usually seen as a gesture of openness.

**Background**
I have answered a related question, and I will use the same source as I used there, namely an interesting interview from Euro News with two communication experts, Stevens and prof. Beattie.

They claim that the open-palms gesture (Fig. 1) is one of all-inclusiveness and openness. It is a sign saying ‘*look I’m an honest Joe*’, and it might be a gesture of ‘*look, you the audience and I, we are in exactly the same boat.*’ In other words, while acknowledging that Trump talks of himself a lot, Stevens and Beattie claim that he compensates these egocentric words with gestures that show that his emotions and the emotions of the public are aligned and so builds connections between him and his audience.

Fig. 1. Trump's open palms. source: YouTube

**Source**
**-** Euo News article What does Donald Trump’s body language say about him by Charlotte Cullen (2016)

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Tags: behaviorism, body-language
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# Question
Title: Why is the chicken crossing the road joke funny?
According to modern psychology why is the answer to the joke "Why did the chicken cross the road?" "To get the the other side." Funny?

According to the relief theory, what are we relieved about?

Could it be that the question invokes a feeling of stress when we don't know the answer? Do we fear that we shall have to expend a lot of energy in trying to work out the solution? Is it stressful having a question put to us which we can't answer? (Just like starting a new job where we don't know what we're doing?)

Or does the stress come from the fear that we will look stupid for being unknowledgeable about the answer to the question?

Why are we then relieved by the answer? Is it because we are relieved that we don't have to expend new energy storing new information because we the information is already so obvious? (But this might not make sense as we do tend store jokes.) But we do not have to alter any of our existing information.

Or does the relief come from finding out that the questioner does not have superior knowledege to ourselves. And we laugh at how idiotic this person is. Like shadenfrauder.

Or... is the laugh a submissive behaviour that we acknowledge that we have been fooled by a greater wit and intelligence?

What is the modern take on this?

# Answer
> 1 votes
I think, as you surmised, the joke isn't all that funny. I would consider the dynamics of the social interaction in which the joke was told as more important than the joke itself.

Laughter is as much a social phenomenon as an involuntary reaction to something humorous. Duchenne laughter is even correlated with increased pain tolerance, in addition to feelings of well-being (https://doi.org/10.1098/rspb.2011.1373). People may laugh or otherwise respond positively if they are seeking social or personal approval.

But as an example of an infamous anti-joke, the chicken-road question "humor" is probably the relief of stress caused by the knowledge that the answer is trivial and thus we are obviated of the need to seek a more clever answer that would render this more of a riddle. The expectation is that the answer is something clever, interesting, or non-obvious, and so when the punchline is revealed, we are relieved and also fooled. The relief comes from the realization that it's not actually important what we said because the joke was a trick and our intellectual status was never on the line.

You may be interested in My Humorous Robot, a conference paper on human responses to an NAO robot telling jokes. The jokes range from actually funny to anti-jokes and human responses are statistically analyzed.

HRI '18 Companion of the 2018 ACM/IEEE International Conference on Human-Robot Interaction Pages 193-194 https://dl.acm.org/citation.cfm?id=3177015

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Tags: humour
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title: NREM sleep and REM sleep

text:
# Question
Title: NREM sleep and REM sleep
Why is the first stage of sleep non-rapid eye movement (NREM) sleep, and why does rapid eye movement (REM) not happen during this first stage, although we remain partially awake?

# Answer
> 0 votes
A few years back when I was doing my studies on this subject of SLEEP, I had some insights and this question gives me an opportunity to express them and I would put them in the form of a hypothesis:

In my opinion, the rapid eye movement does not happen during the first stage of sleep because it is not part of the “sleep mechanism” which the brain initiates to induce sleep, rather it is the outcome of the “waking mechanism” which the brain initiates. The human brain initiates the sleep process by secreting some hormones, primary among them are GABA, melatonin and serotonin. The factors governing this secretion are in general the hour of the day, the bodily conditions and to some extent other environmental factors. Now when the sleep process has been initiated, a normal adult human being passes through the stages of NREM1, NREM2 and NREM(3&4) in his sleep cycle.

Now, the brain has initiated a sleep process, so it has a duty to initiate a waking process also. When should it do that? For that, the brain simply follows a biological clock and after approximately 90 minutes of initiating a sleep process(in a normal adult human), it initiates a “waking process” which is marked by the secretion of some other chemicals, primary among them being the neurotransmitter acetylcholine and then allows the other factors to decide the future course.

So, after approximately 90 minutes of the first sleep cycle, there comes a transition phase where both the “sleep mechanism” and the “waking mechanism” of the brain are active, and it is a sort of a duel, a tussle between the hormones and chemicals of the two mechanism to outdo each other, to overpower each other or to gain the upper hand. The outcome of all this struggle is in the form of RAPID EYE MOVEMENT and the stirring of the memory cells of the brain which results in the observation of DREAMS during this period.

Since generally at the end of the first sleep cycle the factors responsible for the “sleep mechanism” are very strong, the hormones responsible for “sleep mechanism” easily overpower the hormones of the “waking mechanism” and therefore after a short duration of REM sleep, another sleep cycle gets initiated.

Now, approximately 90 minutes after the second sleep cycle of NREM sleep, the brain again starts the “waking mechanism” by secreting hormones. By this time, the body has already received more than three hours of sleep, and so the factors for inducing sleep are slightly weakened but are generally strong enough to continue the sleep process. So this time the tug-of-war between the sleep hormones and the waking hormones ensues for a little more duration of time than the earlier one when again there is REM sleep and then again, generally speaking the body of a normal adult human goes into the third sleep cycle of NREM sleep.

So, in this cyclic manner when the factors for the “sleep mechanism” have weakened sufficiently, the “waking mechanism” of the brain overpowers it and the body is brought to the waking state.

Since the REM sleep is caused by the “waking mechanism” of the brain, in the first stage of the sleep there is no question of having REM sleep.

I am not sure if psychologists who are actively engaged in research work in this subject think along these lines, but I think this explanation does satisfactorily answer the question and any researcher on this subject is most welcome to verify this hypothesis.(https://en.m.wikipedia.org/wiki/File:Sleep\_Hypnogram.svg) \[Hypnogram showing sleep architecture from midnight to 6:30 am, with deep sleep early on. There is more REM (marked red) before waking. (Current hypnograms reflect the recent decision to combine NREM stages 3 and 4 into a single stage 3.)

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Tags: cognitive-neuroscience, sleep
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# Question
Title: Differences in reaction time on visual tasks with and without binocular disparity ques?
Have there been any studies done that test the reaction time to vision processing tasks with and without the benefit of binocular disparities? I have been wondering how much depth information (such as the jutting out of the nose on a face) contributes to visual processing and object encoding in the brain - or if the visual scene is treated like a diorama with 2D images placed at various depths.

My assumption is that if the 3D aspect of the scene components are important then the reaction times would vary.

# Answer
According to these three published studies I found below - reaction time is slower when depth disparity information is withheld, as to whether or not that extra information is actually encoded in the brain is still an open question.

* This first paper by Young Lim Lee; Jeffrey A. Saunders used left and right eye rendered images of novel 3D shapes with and without binocular cues to time test subjects in discriminating whether two images were rotational views of the same object. With a set of three experiments they concluded in all cases that the stereo information improved reaction times.

Stereo improves 3D shape discrimination even when rich monocular shape cues are available
* The second paper by Darren Burke, Jessica Taubert, Talia Higman had test subjects view pairs of photographed human faces briefly through a stereoscope with and without stereoscopic information and were required to identify if it was the same or a different individual. Results were that the subjects had faster reaction times and lower error rates when stereoscopic information was present.

Are face representations viewpoint dependent? A stereo advantage for generalising across different views of faces
* And the third paper by Oliver ZJ, Cristino F, Roberts MV, Pegna AJ, Leek EC the test subjects were split into a mono and stereo groups before being required to memomrize a set of 3D objects and then determine amongst a series of test objects whether or not it was from the set. The test was conducted using a 3D stereo monitor and glasses with the images displayed either with complementary or identical images to either eye depending on the group while 128 channel ERP (event-related-potential) traces were recorded. Results showed higher accuracy for the stereo group and while there was no statistics given for reaction times, the paper concludes with an analysis and discussion regarding the differences in ERP data collected from the two groups.

Stereo Viewing Modulates Three-Dimensional Shape Processing During Object Recognition: A High-Density ERP Study
> 2 votes

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Tags: neuroscience, vision, experimental-neuroscience
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# Question
Title: What is the relationship between anger management difficulties and ADHD?
According to Wikipedia, "Difficulties managing anger are more common in children with ADHD"

Is it that the anger is due to ADHD specifically? Is the anger suggestive of a comorbid disorder? Could it be either?

# Answer
Attention Deficit Hyperactivity Disorder (ADHD) is a type of Neuro-developmental condition whose signs can be seen during early childhood.

ADHD is related to **hyperactive behavior, attention difficulties or difficulty in controlling behavior.** ADHD can affect an individual’s ability, whether at school or work depending on the symptoms.

Usually, the majority of individuals with ADHD tend to have problems with aggression and emotional control.

Anger outbursts individuals with ADHD are often **excessive and explosive**. Some individuals may hyperfocus on their anger and frightened when they lose control and have difficulty understanding their outbursts.

ADHD is strongly associated with **Oppositional Defiant Disorder (ODD)** and can interfere with the successful treatment of ADHD.

I am a teacher at **Accel Centre**, and there are a few students suffering from *hyperactive behavior* while in the class.

This happens because many children and teenagers are unaware of being overly angry or otherwise they are unable to identify the origin of their anger.

On the flip side, many people with ADHD seem to only be able to focus their attention on something they enjoy doing.

References:

*http://www.childhealing.com/articles/adhd.php*

*https://www.myvmc.com/diseases/attention-deficit-hyperactivity-disorder-in-adults-adult-adhd/*
> 3 votes

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Tags: abnormal-psychology, adhd, psychology
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# Question
Title: How does one distinguish BPD anger from ADHD anger?
Some people with ADHD are known to have difficulties in controlling anger.

Whenever a person with ADHD has difficulties in controlling anger, how does one determine whether or not that person really has BPD? By which I mean to ask, how do we know that the anger is symptomatic of BPD rather than ADHD?

# Answer
> 5 votes
**Borderline Personality Disorder (BPD)** is a complicated diagnosis to understand and treat. A painful mix of **emotional trouble, unstable relationships and self-destructive behavior**, including suicide attempts are associated with BPD.

Experts have given a new name to BPD as Biosocial disorder. People who develop BPD are highly emotional, sensitive and reactive, more immediately and intensely than most people. And once a powerful emotion is triggered, it takes them longer to return to their emotional baseline.

**Attention Deficit Hyperactivity Disorder (ADHD)** is a chronic condition which includes **attention difficulties, hyperactivity, and impulsiveness.**

ADHD is often seen in childhood persisting into adolescence and adulthood, which contributes to hyperactivity, low self-esteem, disturbed relationships and attention difficulties at school or work.

In relation to anger, individuals with BPD report higher traits of aggression and hostility when provoked than individuals with ADHD.

Furthermore, individuals with *BPD exhibit a higher state of anger and stress-dependent anger increase.* In BPD patients, aggression and anger were positively correlated with emotion regulation deficits.

Being a Special Education Teacher at **Accel Centre**, there are kids and adults with special needs education who require ***vocational training for special needs*** that helps them to develop social skills and anger management.

*Reference: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5356413/*

# Answer
> 3 votes
The difference is in consistency. Bipolar disorder there is usually episodic; quick, drastic changes between normality, mania, depression and anger. ADHD on the other hand is chronic and affects attention and behavior rather than mood. Anger is of course a symptom but usually only situational. Over a period of time, bursts of anger and other moods can be documented and the pattern matched with ADHD, Bipolor, Autism or whatever similarly presenting issues.

**BPD (Borderline Personality Disorder)**

I was sure your question was asking about bipolar. Maybe I read it wrong. Distinguishing between BPD and ADHD is another matter because it's not about distinguishing per-se, more about deciding if you have one or both as there is symptom overlap. Again the answer is a complete medical and behavioral history however. The idea (as with above) is to gather all presenting symptoms then if you have the non overlapping symptoms of either or both ADHD (e.g.hyperactivity, disorganisation, attention) and BPD (e.g.emptiness, suicidal thoughts, self harming), they are diagnosed. It's very unlikely a person will present with only the overlapping symptoms but in that case...I'm not sure.

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Tags: abnormal-psychology, personality, adhd, personality-disorder
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# Question
Title: Does high IQ give cause to doubt an ADHD diagnosis?
My friend was diagnosed with ADHD as a kid, but her parents disagreed with such a diagnosis on the grounds that she had a high IQ which was discovered when her psychologists and psychiatrists were investigating what mental illnesses she may have had.

Edit: There was medicine prescribed, but she and her mother can't remember the name of her prescribed medicine.

I thought back to that when reading this:

> Myth #10: Kids with ADHD won't amount to anything.
>
> Many famous artists, scientists, and politicians had ADHD as children. Here's a list of some well-known celebrities with ADHD:

It seems to me based on that and the things I've heard that people think ADHD in children causes poor academic performance, but the myth is that such poor academic performance is suggesting that said children "won't amount to anything".

**So, people don't think that children with ADHD can be geniuses?**

Expansion: **Is it, however, also a misconception (whether as prevalent as a myth or not) that people who are thought to have mental illnesses instead are geniuses or something like that?**

By genius I mean someone with a high IQ.

# Answer
> 7 votes
Sounds to me like someone is making a logical fallacy here, though the origin of this fallacy isn't clear to me.

We cannot go from 'poor academic performance', to 'not amounting to anything', to 'having a low IQ'. These are not relationships of cause and effect.

The motivation to do something ('amount to something', if you will) is driven primarily by the reward-center. The neurotransmitter 'dopamine' is considered to be a large player in this game. Dopamine tends to project to the areas associated with reward (and these areas are clustered into the abstraction known as the pleasure center). Incidentally, ADHD has shown to be a dysfunction of executive reasoning as a result of low dopamine levels.

IQ is not determined by executive functioning. IQ is almost independent of executive functioning. If they were interchangeable, then Albert Einstein would have a very low IQ compared to, say, Donald Trump. I say that it is 'almost' independent because it is not clear that there is no relationship between the two at all. Studies have shown that ADHD sufferers show an average increase of 4.5 IQ points after long-term use of dopamine-reuptake inhibitors. \[1\]

You might also be interested in this page to answer the second part(?) of your question. It is well-written and extremely insightful.

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Sources:

\[1\] Millichap JG (2010). "Chapter 3: Medications for ADHD". In Millichap JG. Attention Deficit Hyperactivity Disorder Handbook: A Physician's Guide to ADHD (2nd ed.). New York: Springer. pp. 121–123.

# Answer
> 1 votes
*Attention Deficit Hyperactivity Disorder (ADHD) is a type of neurological developmental condition that affects in the childhood and can continue in adulthood.*

It is a particular set of how the **brain functions and related behaviors** of an individual with ADHD.

Children with ADHD are hyperactive, have trouble paying attention and unable to control their impulses.

Some people with ADHD might have higher IQs, but assuming that there’s a correlation may be harmful because it can keep your child from getting the help they need.

The fact is, intelligence and ADHD don’t go hand in hand. ADHD can affect an individual’s ability, whether at school or work depending on the symptoms.

At times, everyday tasks can be quite difficult which can give off the impression that such an individual has a low IQ.

At **ACCEL**, a range of verbal, memory and problem-solving tests are carried out for special needs education. On the flip side, many people with ADHD seem to only be able to focus their attention on something they enjoy doing.

*Source: https://www.sciencedirect.com/science/article/pii/S0160289616303324*

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Tags: abnormal-psychology, intelligence, iq, adhd
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# Question
Title: Is there a difference between ADD and ADHD?
These terms are often used interchangeably.

Is there a difference?

# Answer
They are interchangeable. ADD was a term used throughout most of the 80s and ADHD aftewards. In the *Diagnostic and Statistical Manual of Mental Disorders 1980* (*DSM-III*) published by the *American Psychiatric Association* (*APA*) it was named ADD and the name changed to ADHD in the 1987 edition, *DSM-III-R* (which I can find no online sources of).

ADD has been used to describe a sufferer without the observable hyperactivity but it is still essentially the same thing. Which leads to the confusion.

Terms used to describe the condition include:

* Before 1980, *hyperkinetic reaction of childhood*
* 1980-1987, *Attention Deficit Disorder (ADD)*
* 1987, *Attention Deficit and Hyperactivity Disorder ADHD*
* 1994, *ADHD* was disected into subtypes, *predominantly inattentive (ADHD-PI or ADHD-I)*, *predominantly hyperactive-impulsive (ADHD-PH or ADHD-HI)*, and *combined type (ADHD-C)*.
> 6 votes

# Answer
**Attention-deficit/hyperactivity disorder (ADHD)** or is it **Attention Deficit Disorder (ADD)**?

**ADHD** is a neural development disability which can be related to the brain function and behavior of an individual.

Individuals with ADHD are hyperactive, have trouble paying attention and are unable to control their impulses.

ADHD is a brain disorder which can interfere with the daily task at home or work. Both the terms ADD and ADHD refer to a syndrome found in both children and adults with visible characteristics by restlessness, hyperactivity or impulsiveness.

A few signs for individuals with ADHD can be seen as,

* *Lack of attention*: Includes disorganization, problems staying on task, constant daydreaming, and not paying attention when spoken to directly.
* *Impulsiveness*
* *Hyperactivity*: Involves squirming, fidgeting, tapping, talking, and constant movement.

On the other hand, **Attention Deficit Disorder (ADD)** is an outdated term used for Attention Deficit Hyperactivity Disorder. This condition can vary from person to person and used to refer an individual who had trouble focusing on anything rather than being hyperactive.

ADD is a type of ADHD that doesn't involve constant movement and fidgeting. But it's a blurry distinction.

I have been treating **ADHD** and other **vocational training for special needs** at **Accel Centre** for the past 20 years and have realized that it is not a disability or deficit instead of a trait an individual can have with some positive and negative outcomes.

References:

*https://www.healthline.com/health/adhd/difference-between-add-and-adhd*

*https://www.webmd.com/add-adhd/childhood-adhd/add-vs-adhd*
> 1 votes

# Answer
ADD is the term commonly used to describe symptoms of inattention, distractibility, and poor working memory. ADHD is the term used to describe additional symptoms of hyperactivity and impulsivity. Both are included in the medical diagnosis of ADHD.

1980-1989, Attention Deficit Disorder (ADD) 1997, Attention Deficit and Hyperactivity Disorder ADHD
> -1 votes

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Tags: terminology, adhd
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title: Can adults adapt to less sleep?

text:
# Question
Title: Can adults adapt to less sleep?
I am asking whether adults, especially in circumstances like a monastery or Zen center, can become able long-term to sleep only about 4 to 5 hours a night? So, that would mean: no children to care for, no heavy labor, lots of time spent meditating and doing other things that the body would find restful and undemanding...

Can the mind get along on much less hours of sleep than the usual adult? I am not asking about the absolute numbers, only if it can be reduced and sustained over years, or permanently?

# Answer
A paper by Kaul et al. from 2010 suggest that meditation can indeed decrease the need for sleep. Meditation acutely improves psychomotor vigilance, and may decrease sleep need

Quote from conclusions:

> These results suggest that meditation provides at least a short-term performance improvement even in novice meditators. In long term meditators, multiple hours spent in meditation are associated with a significant decrease in total sleep time when compared with age and sex matched controls who did not meditate. Whether meditation can actually replace a portion of sleep or pay-off sleep debt is under further investigation.
> 1 votes

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Tags: sleep
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# Question
Title: What speaker is commonly used for low-latency audio stimulation
We need to purchase a new speaker for audio ERP study, so the sound should be played in lowest possible latency with lowest possible jitter. I have seen quite a few suggestion on the OS/driver/sound card part, but it seems that there is less information about how to choose the proper speaker.

What is the common latency between the the time point when the sound card actually start sending out signal, and the time point when the speaker actually start vibrating? And are there any point that we should take care when choosing the speaker?

# Answer
> 2 votes
There is generally an intervening stage between the sound card and the speaker, the amplifier. From the output of the amplifier to the speaker, there is an electrical signal traveling at like 0.01C that then drive the speaker via an electromagnet. The transmission and transduction time is essentially zero. Further, you can safely ignore any jitter.

For powered speakers, or amplifiers, there are all sorts of models. Some might have some built in filtering that could introduce a delay, but it is probably negligible.

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Tags: methodology, experimental-psychology
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# Question
Title: Is the amount of learning modulated by reward transmitters?
The human brain is a signal processing system. Input streams contain sensory, motor, reward and possibly more signals mixed. I wonder if neuro transmitters associated with reward increase or decrease memorization of those streams. That would result in a tendency to memorize streams co-occurring with high reward over those co-occurring with low reward. Thus, attractors would settle for better streams and we would perform actions optimizing the reward.

# Answer
The effect of dopamine signaling is one of the areas where computational neuroscience has provided insight into brain mechanisms, specifically via Reinforcement Learning (RL) models.

Based off this paper and PHD thesis from Dan Rasmussen, this first began with this publication from Schultz showing that dopamine acts as a reward signaler. From the abstract:

> Dopamine neurons are activated by rewarding events that are better than predicted, remain uninfluenced by events that are as good as predicted, and are depressed by events that are worse than predicted. By signaling rewards according to a prediction error, dopamine responses have the formal characteristics of a teaching signal postulated by reinforcement learning theories.

To answer your question directly, it does seem the speed/plasticity of learning is modulated by dopamine neurons.
> 2 votes

# Answer
**A bit of context**

In mammalian brains, a main neurotransmiter linked with reward is Dopamine. This molecule is produced in the Ventral Tegmental Area (VTA) and in the Substantia Nigra (SN).

In a very famous study, Schultz recorded neurons in this two regions (at the time, we didn't really make the difference between them), and realised that the activity of these neurons was linked with reward. More precisely, neurons were coding for Reward Prediction Error, a feature that is implemented in Reinforcement Learning models.

Recently, some researchers decided to adress your question. To do this, they used optogenetics, wich is a technique that permit you to modulate the activity of neurons with light.

You can read the paper here : McNamara et al. Nat. Neurosci. (2014)

**What are the main results ?**

Mice with increased dopamine neuron's activity had better performance in a spatial task. They were **better** at learning a new maze. On top of that, the increased activity of VTA neurons induced a higher amount of specific oscillations (called Sharp Wave Ripples) in the Hippocampus, a structure important in spatial learning. We start to have strong evidence that this oscillations are important for memory, as disrupting them impair memory (see Jadhav et al. Science (2012) and Girardeau et al. Nat. Neuosci. (2009) if you are interested in the subject)

Note that this study was done in mice. Their is probably papers making a link between the activity of the VTA and learning using FMRi on humans, but I don't know the litterature enough.
> 2 votes

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Tags: neuroscience, cognitive-neuroscience, neuro-transmitters, reward
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# Question
Title: What is the term for learning to group objects
I've been googling this for a few days now but haven't come across what I'm looking for.

**Scenario**: A child has to learn how to identify species. When first learning, they might mistake a cat for a dog. They both have four legs and a tail. However, as they are shown more and more examples of cats and dogs, they build up a more detailed definition of what a dog is and what a cat is ... specifically by being shown many many examples (different examples at all ends of the spectrum ... big and small) of these two species.

I was reading about this area of cognitive psychology a few years back (quite a few years back). I wanted to refresh and study up on this some and read what I can about it, but can't because I'm not googling the correct terminology. Any direction would be greatly appreciated. Thanks.

# Answer
I would suggest you start with the Wikipedia articles on Categorization and more specifically Prototype theory.

While the Categorization article gives a number of branching points for you to drill down on and hone in and/or prime your thinking for further searches, the Prototype theory topic is where my mind went upon first reading your question

Even though the focus of prototype theory is on the shared artifact of language which you may or may not have been thinking of when you posed the question. I would expect any further reading you did on the topic to have plenty to say about the individual language user/learner also.

...

As a follow up I also found the following article which is from the perspective of Developmental Psychology.
> 4 votes

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Tags: cognitive-psychology, cognitive-neuroscience, recognition
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# Question
Title: Can one reasonably guess the gender of a person from their writing/speech contents?
Is it possible to reasonably guess the gender of a person from a **random sample** of their writing (text, not handwriting)?

How about from the contents of their speech (not including their voice, of course)?

# Answer
> 4 votes
While you are probably better to ask your question over at the AI Stack Exchange for more practical answers on how to accomplish the task, I would also suggest you could take a look into the topics on Wikipedia for Sociolinguistics, and also Language and gender for the underlying theories as to why Machine learning models are able to make guesses/predictions with upwards of 80% accuracy in trained models such as the following.

So to fully answer your question

> Can one reasonably guess the gender of a person from their writing/speech contents?

What is a 'reasonable guess' is not something I can define and is something you would wan't to think seriously about before using the predictions for anything of import to those you are labelling! However it would seem you can make a significantly better than random guess.

# Answer
> 0 votes
**Guesswork is not what this site is about.**

Statistical analysis of factors of "The Big 5" personality traits:

have been extensivley studied and are well understood in terms of the sex differences that emerge from biology, and also but less so from cultural differences.

It would be possible to design studies to research the various different modes and media of writing, given sufficient funding and analytical clout to do what you ask.

As far as this answerer can determine, no-one has yet given it much attention as it is a low-priority compared to the social issues that prevail in societies today. What you are asking would be considered trivial or "Blue Sky" research at best.

# Guesswork:

Statistical analysis of many factors, correcting for others is (reductio) extended inductive reasoning, which is (reductio ad absurdum) guesswork.

Get the financial backing to gather a big enough (set of) sample(s) that you can leverage analysis out of (and the mental tools to bring it to order) and you're all set to make a "guess".

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Tags: gender, speech, writing
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# Question
Title: Why can't we use 100% of the brain in a certain moment?
I know it's a myth that we only use 10% of our brain, but the point is that we use less than 10% in any given moment; only by using different parts of our brain for various tasks over time do we ultimately use 100%.

Let's imagine that we have a GPU, a CPU, a quantum computer, and a biological computer that can work perfectly. It's obvious that some of them are going to be better at performing some things than others, but the point is that anything that can be computed can be done by any of them.

I think that similar logic should apply within our brain: Although some areas of the brain might not be too good at processing some things, they could also work towards the result.

What is the reason that this doesn't happen? I believe that it would be a significant improvement in the brain's performance, although it would be very energy consuming.

# Answer
> 15 votes
The widely quoted figure of "10% at a time" is actually overestimating simultaneous brain activity by up to an order of magnitude. As demonstrated by Lennie 2003 (Current Biology), the

> number of neurons that can be substantially active concurrently

is possibly as small as 1% of the brain's neurons, due to the *high metabolic cost of spiking*. Generally, metabolic cost is a major determinant in brain activity. This in turn entails that even

> less than 10% of cortex could be active at all

, to quote Lennie again. This number, derived for humans, is lower than for other animals, who are capable of sustaining a larger fraction of their brain's neurons simultaneously. This means that rats and hamsters use more of their brains than humans do.

Paradoxically, the highest metabolic cost comes from inhibitory activity. Also, neurons restrict their own firing rates via refractory periods. For the best example of a failure of this inhibitory control of excessive spiking, consider epileptic fits, which correspond to extreme synchronization of neural activity, in a sense an over activation of the brain.
I think considering that two examples of brains showing more concurrent activity than the healthy human brain are 1. the rat brain, 2. the epileptic brain, it becomes obvious that increasing total activity would not inherently improve brain function.

# Answer
> 6 votes
Far from being one single organ performing a single homogeneous function, the brain is actually several lobes, and each lobe is like a separate organ performing a dozen functions. Putting it in another way, the brain is not like a "thinking machine", it is more like a collection of computers, instrument panels of an aircraft, radars and sonars of a submarine, the memory banks and backup systems of the New York Stock Exchange and all the banks on Wall Street, and the automatic self-balancing sensors that make a Segway look feeble, and then some.

So, if all the neurons of the all the separate lobes of the brain fire at the same time (which is what 100% brain usage is all about), it means that something is going very, very wrong.

Besides, the brain is engineered for redundancy. It is NOT built for firing all at the same time, because some aspects of the brain are like Plan A, Plan B and Plan C; If Plan A fails, it fires Plan B, and if that fails, Plan C. Firing them all at once defeats the purpose of redundancy.

Also, some other aspects of the brain may be compared to a multi-stage rocket, where Stage A, B and C fires up sequentially, and not simultaneously. Sequential processing is vital for various brain functions.

# Answer
> 4 votes
Unlike a computer, where the circuitry is information agnostic (it can represent anything digital), neural networks (both biological and artificial) are not. The organization of neurons (their connections and the strengths of those connections) determines what they represent and how they process information. Thus, the visual cortex cannot be recruited for audio processing when your eyes are closed because the visual cortex is only capable of the function of processing visual information (very different from a GPU).

Thanks to neuroplasticity, the visual cortex can (with much training over a long period of time) actually be recruited for other functions (including audio processing) in blind people for example, but then that becomes the only function it performs - ie, neuroplasticity does not give the brain a context-switching capability like computers have.

# Answer
> 4 votes
Neurons are extraordinarily expensive to make, maintain, and use (Laughlin et al, 1998; Stone 2018). Half of a child's energy budget, and a fifth of an adult's budget, is required just to keep the brain ticking over (Sokoloff, 1989; Levy and Baxter, 1996). For both children and adults, half the brain's energy budget is used for neuronal information processing, and the rest is used for basic maintenance (Attwell et al, 2001). The high cost of using neurons accounts for the fact that only 2-4\\% of them are active at any one time (Lennie, 2003). I suspect that, if all neurons could be active at the same time then the enormous amounts of energy required would probably result in cooking the brain.

References

Attwell, D and Laughlin, SB. An energy budget for signaling in the grey matter of the brain. J Cerebral Blood Flow and Metabolism, 21(10):1133–1145, 2001.

Laughlin, SB, de Ruyter van Steveninck, RR, and Anderson, JC. The metabolic cost of neural information. Nature Neuroscience, 1(1):36–41, 1998.

Lennie, P. The cost of cortical computation. Current Biology, 13:493–497, 2003.

Levy, WB and Baxter, RA. Energy efficient neural codes. Neural Computation, 8(3):531–543, 1996.

Sokoloff, L. Circulation and energy metabolism of the brain. Basic Neurochemistry, 2:338–413, 1989.

Stone, JV. Principles of Neural Information Theory: Computational Neuroscience and Metabolic Efficiency. Sebtel Press (published 8th June 2018).

# Answer
> 1 votes
I think the problem with your question is that we don't "use" our brain. It appears that our brain have different patterns of activities, in different regions, at different times and, to the best of our knowledge, all this factors are what produce our perception of the environment, the reaction we have, and probably our thougths and identity (the "we" in your question).

Since their is no "we" outside of the brain that can decide to activate or not any given region of the brain, their is not really an asnwer to your question.

Now your question could be reformulated to : "**why is the brain not activated at 100% at any given time**"

By activation, we usualy talk about action potentials, wich are produced by neurons. This is considered to be the fundamental way of two neurons to transmit information to one another. You can consider this action potentials as a binary code (although it is probably more complicated, see neuromodulation for exemple). In this exemple, an action potential is a 1 and no action potential is a 0. If no neurons are firing, you only have 0, wich convey no information to other neurons (indeed, you can simplify this signal to 0 x the time elapsed). On the other hand, if every neurons are firing in the same time, you don't convey information too (this can be simplified by 1 x the time elapsed). The only way to convey information, and as you might have understood I am talking in an information theory way, is to produce a mix between zero and 1, wich is, in our exemple a serie of action potentials and no action potentials. In you exemple, it would be like if in a CPU, every transistors were activated in the same time. You don't have any information conveyed.

An other exemple can be an assembly of persons in a room. If nobody talk, there is obviously no information conveyed. But if everyone is talking at the same time, they don't understand each other.

In the brain, an activation of every neurons can happen in certain regions. It is called epilepsy, and it is not really functional.

So 100% activation is possible in the brain, but it is not efficient computationaly, as it does not produce information.

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Tags: neuroscience, neural-network, performance, brain
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# Question
Title: Looking for text books comparing animal and human brain
Are there any papers or textbooks comparing animal nervous system and human's ? I'm most interested in "higher" animals such as mammals(Chimps, dogs etc.)

# Answer
> 2 votes
I believe what your looking for is a book on Comparative Neuroanatomy the only text book I could find in the field was: Comparative Vertebrate Neuroanatomy: Evolution and Adaptation but you will find a number of web pages via google.

Comparative Neuroanatomy

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Tags: neuroscience
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title: "Dyslexia" in reasoning?

text:
# Question
Title: "Dyslexia" in reasoning?
I was trying to use logical argument with a friend of mine recently, and found that she was missing my point and completely misunderstanding my position. So I wonder if there is something like dyslexia of reasoning/logic, a brain condition that makes people unable to understand and follow logical arguments.

# Answer
Cognitive dissonance is often a problem when trying to convince someone of your position. Depending on the subject matter and how closely the position is held for the opposing party it can be very difficult to follow even logical well reasoned arguments. The opposing party often has a framework of reality in which they make sense of various situations or concepts. If a new concept doesn't fit within that framework there is often underlying reasons as to why the argument is unable to land. So until the deeper views are addressed you are arguing in vein.

For example in order for something you postulate to be true, it may require the opposite party to reconcile other beliefs that are deeply held in a way that they are potentially unwilling to address, or see no reason to address due to unwanted stress or emotional distress in addressing the beliefs.

Alternatively there are neurological deficits or disabilities that could make getting your point across more difficult, but at least from my experience it is often a case of Cognitive Dissonance.
> 4 votes

# Answer
So let me start off by saying that the word dyslexia is a well-defined term describing a condition typically affecting the left angular gyrus.

If you're looking for a biological condition that leaves a similar effect on reasoning, I'm afraid you've got in backwards. Humans are rational beings, but that doesn't mean we always, or even often, behave rationally.

Instead, we're often driven by heuristics, rules of thumb, that helped us survive in the bush, but fail to accurately handle larger, more abstract problems.

Another issue is identity, there have been hundreds of books discussing group identity's powerful effect on our reasoning, but to distill it as much as possible: let's say someone is an anti-pencil, for whatever reason they absolutely hate pencils, and there's a group of these pencil-hating buffoons. As they assimilate into this anti-pencil group, the pencil hatred starts to become part of their identity. Once it's part of their identity, attacking their beliefs head-on is futile.

Instead of helping them to see the fallacy of their ways, counterarguments are often perceived as a personal attack; akin to insulting your taste in music, clothes, or weight.

If you are looking for ways to help, you're actually much better off inviting your pencil-hating friend to imagine what life must be like for pencil users.

Source: https://www.newyorker.com/magazine/2017/02/27/why-facts-dont-change-our-minds

Ps: If you want to know more about why, both biologically and sociologically, people can be so immune to rationality,I strongly recommend a book: Behave, by Dr. Sapolsky.
> 3 votes

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Tags: cognitive-neuroscience, abnormal-psychology, attention, cognition
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# Question
Title: Put a fixation cross on top of a image in Expyriment?
I wanted to try to put a fixation cross on top of images presented to avoid subject eye movements as much as possible.

I am using Python's Expyriment package and thought that after `present` with a `expyriment.stimuli.Picture` I could do a `present` with an `expyriment.stimuli.FixCross` object using the `clear`or `update` input arguments. But this does not seem to work.

# Answer
> 1 votes
This should work:

```
picture = expyriment.stimuli.Picture("/path/to/picture.jpg")
fixcross = expyriment.stimuli.FixCross()
picture.present(update=False)
fixcross.present(clear=False)

```

Alternatively, you can first plot the fixation cross on top of the picture and then present it:

```
picture = expyriment.stimuli.Picture("/path/to/picture.jpg")
fixcross = expyriment.stimuli.FixCross()
fixcross.plot(picture)
picture.present()

```

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Tags: experimental-psychology, software
---


# Question
Title: Integrated Information Theory - If correct could humans create artificial consciousness?
First off please keep in mind I am self-learning and am learning about this for fun, I have no end goal. I'm trying to make predictions about what I am learning implies or means, so I can ask better questions and clarify what I should learn/focus on learning. I know I need to spend tons more time in understanding the physics and biology that we currently understand. I'm looking for feedback that can help me either confirm my understanding or correct it and/or point me in directions that will help me better develop it so I can ask better questions in the future.

This assumes IIT is a valid theory.

It seems to me IIT implies that consciousness not only requires integration, but in order to achieve integration the system must be dynamic and able to respond spatially to feedback within the system. As I understand it our neurons grow and die, they can move, they receive inputs from their connections but can also be influenced by molecules that make their way to them indirectly. There is an end result of all the behavior of the neuron and that is the movement of electrons. The molecules and cells surrounding the neurons, provide it the ability to release the action potential. Or the stored up energy that must reach a certain threshold in order for the neuron to fire. This firing is what must be in harmony and certain firing patterns in theory results in conscious experience.

So if humans were to artificially generate consciousness as we experience it (using non-biological methods) this would require us to develop a system that can arrange and rearrange neurons or nodes spatially that can release action potentials of electrons(not sure I'm using correct terminology/physical process) in symphony. The neurons would need to be able to change connection weights not only through internal inputs but also through external inputs, and not only by connected nodes. We would need to understand what causes neurons to grow along particular paths or make particular connections... I assume some of this is known or theorized about. It also seems that certain parts of neuronal intelligence is crystallized or more or less unchanging where as other parts do change and use relationships between the unchanging or slow to change parts in conjunction with more dynamic components that allow for variation in abilities to connect.

IIT seems to imply that conscious experience lies in certain configurations of the electron field (what happens beyond that is unclear) but that seems to be the end result of the actions that any particular group of neurons is taking. I suppose not all, because it also serves the purpose of communication and coordination through out the body. It doesn't seem that synchrony in neuronal behavior coordinates chemical arrangements that would explain experience, but it does coordinate electrical fields as an end result. I'm trying to understand if that is a correct understanding whether that is one of the main outputs of neuronal firing.

# Answer
IIT implies that just about everything is 'conscious' (to a degree) in that you can measure its integrated information to say how conscious it is, while accepting that what we as humans typically describe as 'consciousness' is a very high value of this measure. That's sort of the whole point of the theory: having a definition of consciousness that starts from a more basic principle ('integrated information') rather than starting at "humans are conscious" without defining what it really means to be conscious.

High levels of integrated information are not easy to achieve with typical computers we use today, but nothing about the theory says it cannot be done. If you have a sufficient level of integrated information, we can call that consciousness based on IIT.

IIT does not say anything about implementation of such a system, even though your question implies that it does (you could view this as either a weakness or a strength depending on your perspective); there are certainly ways to connect artificial systems dynamically without them needing to be neurons. It is true, however, that an individual neuron is far more complex than typical artificial instantiations of neurons, like the nodes of an artificial neural network.

As far as your paragraph beginning "*IIT seems to imply that conscious experience lies in certain configurations of the electron field*" I don't know what this means or where your got it; IIT doesn't say anything like this. IIT says that consciousness is what you get when you connect information to other information; for example, placing information you are measuring from the world right now in the context of your life's experience involves integrating information from your sensory systems with your memories. Computers can already achieve this to some degree, the part about human consciousness that is remarkable is just how deeply and rapidly (and automatically) these comparisons occur in parallel.

---

Koch, C., & Tononi, G. (2008). Can machines be conscious?. Ieee Spectrum, 45(6).
> 2 votes

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Tags: neuroscience, theoretical-neuroscience, consciousness, neurophysiology, artificial-intelligence
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# Question
Title: Why do we sometimes(i often) go to trance while listening to music?
What's the scientific reason behind it?

I can't quite figure out what's around me and it feels so soothing same as the effect of meditation. It feels like an enlightenment.(I feel like I'm connected to a higher deity)

# Answer
If you take a look at this quick article: The Neuroscience Of Trance or the full published study the article refers to: Brain Network Reconfiguration and Perceptual Decoupling During an Absorptive State of Consciousness scientists used fMRI to view what was going on in the brains of shamans as they either entered into a trance or purposefully stopped themselves from doing so while listening to drumming.

One of the things they noted was a dampening of the sensory pathways - there theory being that while the drumming beat was the most prominent external stimulus, it's repetitive and predictable patterns allowed it to be gated out/ignored while its ongoing presence prevented reorienting to the usual random environmental distractions.

I would expect the music your listening to is doing more or less what the drumming does for the shamans.
> 1 votes

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Tags: music
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# Question
Title: Is there any evidence for or against the existence of neurons that encode surface slant in vision?
In the way orientation columns display selectivity for various edge orientations projected on the retina which is then repeated at various angles in a localised region of the cortex. I am wondering whether in an analogous fashion if any similar neuronal circuitry has been shown to represent variations in the surface slant at the region being projected onto the retina.

*By slant I mean a measure of the surfaces orientation away from co-planar with the visual focal plane.*

Perhaps this information is extracted from binocular receptive fields?

If it hasn't been found then I guess I'm also wondering if anyone has ever looked? and or how the depth information from binocular receptive fields is encoded/represented for further processing?

# Answer
Yes there is evidence of the encoding of surface slant in the visual field

* Disparity-Based Coding of Three-Dimensional Surface Orientation by Macaque Middle Temporal Neurons

> We now show that MT contains robust, disparity-based signals regarding the 3-D orientation (tilt and slant) of planar surfaces. This tilt selectivity does not result from vergence eye movements or subtle monocular dot-density cues, and approximately one-half of MT neurons respond more strongly to a tilted stimulus (i.e., a nonzero slant) than to any frontoparallel stimulus of the same size (data not shown). In addition, we show that the tilt preference of MT neurons is primarily independent of the mean depth and slant of the surface, properties that may simplify the extraction of 3-D orientation signals from a population of MT neurons.
* Representation of 3-D surface orientation by velocity and disparity gradient cues in area MT

> This study demonstrates that single MT neurons signal 3-D surface orientation (tilt and slant) via selectivity for velocity and disparity gradients, and to a lesser degree, for texture gradients. Selectivity is similar in multiunit activity recorded simultaneously, suggesting that 3-D surface orientation tuning is clustered in MT. Tilt selectivity is generally enhanced when multiple gradient cues are presented together, indicating that MT may integrate cues to represent surface structure with greater fidelity. This occurs despite the fact that tilt preferences for disparity and velocity gradients are poorly correlated overall. In addition, we found that responses to the combined stimulus, which contains all three gradient cues, are well approximated by a linear weighted sum of responses to the individual cues, with disparity and velocity gradients weighted most heavily. This study provides the first systematic examination of neural integration of multiple gradient cues to surface orientation and suggests that area MT contains an early multicue representation of 3-D surface structure.
> 2 votes

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Tags: neuroscience, theoretical-neuroscience, vision
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# Question
Title: Do you know any good tutorial on designing EEG experiments with PsychoPy?
I'm trying to find good documentation on using PsychoPy to measure Event-Related Potentials. In particular, I want to measure and compare the amplitude of the N170, a face-sensitive ERP, when presenting neutral versus threatening faces. I would be using the Emotiv Epoc EEG headset, whose validity for research on the N170 has been documented.

# Answer
> 2 votes
A collection of classic EEG experiments implemented in Python and Jupyter notebooks. Currently, all experiments are implemented for the Muse EEG device and using psychopy lib for stimulus presentation. Classification is made offline though. But I'll post very soon an online tutorial: https://github.com/NeuroTechX/eeg-notebooks/tree/master/notebooks

# Answer
> 2 votes
You can buy the book in particular Chapter 18: Building an EEG study. There is also the PsychoPy forum with 50+ questions about EEG. You could also go to the lead developers OSF page and steal some code there from his EEG experiments.

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Tags: cognitive-psychology, cognitive-neuroscience, software, event-related-potential
---


# Question
Title: What is the difference between getting high( i.e. using alcohol or similar things) and getting unconcious using general anesthesia?
I searched the internet about the difference but couldnt really understand it.I am not asking about the difference in the type of drugs used, Iam interested in the difference in the state of unconciousness.(Iam not sure whether "getting high" can be called unconcious.)

# Answer
> 1 votes
The short answer to what the difference between getting high and getting unconscious using general anaesthesia - It simply boils down to a matter of dosage levels and medical supervision!

And now to clarify ...

When you are put under general anaesthetic the attending anaesthesiologist will be administering possibly multiple drugs that work together to achieve the required effect of preventing you from moving your body, and your brain from being aware of whats happening to your body. The precise dosages and the timing of there administration are carefully chosen to ensure you stay blissfully unaware and immobile for the duration of the procedure.

Now compare that to you going out for a night on the town where ideally the only one administering any drugs is you (for better or worse) - barring any accidental overdoses from you pounding down a full bottle of spirits in one turn - the dosages you put in your system are thankfully just not in the same league as what you would receive on the operating table and so you just get high or obnoxious as apposed to getting into what is technically a medically induced coma.

One of the major characteristics of that induced coma is that your body looses its protective reflexes and your at the mercy of the attending medical teem to prevent you from choking on your own tongue - when you hear of someone outside of a hospital dying from an overdose whether it be drug or alcohol, a lot of the time the cause of death isn't the toxicity but that same loss of protective reflexes that doesn't save them as they asphyxiate on there own tongue or vomit after slipping into a deep sleep (or coma).

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Tags: unconscious
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# Question
Title: Does total time exercising matter for cognition more than the time exercising continuously?
Will my brain benefit from cardio equally if I exercise at the same intensity level for 12 10 minutes sessions as it would for one 120 minute session?

# Answer
Before giving my gut feeling as an answer in the final paragraph I'll first have to explain why I don't think the question can be answered in absolute terms (at least not without additional restrictions).

To start with I'll remind you that our bodies don't just flick over to exercise mode but instead ramp up and down in response to the demands put on them. As a result to make a proper comparison between bursts and sustained exercise isn't as simple as multiplying there duration.

If we take our \[calculated MHR\]\[1\] as a basic measure of exercise intensity then say a respectable level is 50% to 70% of MHR, the quickest we are going to be able to get into that heart rate zone is with an all out sprint (a very bad idea without warming up) at which point our heart rate will overshoot the mark (sometimes reaching well over 100% since the MHR calculators are pretty rough without doing a full fitness workup) and then drop and eventually settle on a rate after maybe 2 minutes.

But the more likely and sensible scenario is that we will start exercising at what we feel is the correct intensity and our heart rate will eventually increase over the space of several minutes so that it may be 5 to 10 minutes before we get in the zone.

So while I completely understand where you are coming from with your question it is one that I see a way of testing experimentally - and so i will just give you my subjective answer in what follows.

Since the physiological changes in the brain (\[such as increased blood flow, seratonin, BDNF\]\[2\]) would I believe happen toward the start of the exercise session and then your brain would adapt to the new exercise demands and stop producing extras of all those goodies leaving them to begin dissipating before you ended the session and for a duration of time after means you would be better off doing bursts of exercise throughout the day to keep triggering that brain response that re-releases the goods.
> -1 votes

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Tags: exercise
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# Question
Title: What is the medical term for semi-mindless activities to help reduce anxiety? ... such as gardening, mowing, cleaning... perhaps driving
What is the medical term for semi-mindless activities to help reduce anxiety? ... such as gardening, mowing, cleaning... perhaps driving.

I recall that, maybe, the word asynchronous was part of the term *** which based on present answers now seems less likely *** .

# Answer
I have read it mentioned as **grounding-** techniques or activities. Activities that pull you into the present, and, if possible, fulfill you by giving you the impression towards achieving a goal.
> 3 votes

# Answer
I have not been able to find any term, medical or non-medical, which includes the word *asynchronous*, but to add to the answer by @user20460 there is the non-medical term *hobbies*.

Taking part in hobbies and other interests is recommended to anyone who suffers from anxiety and/or depression because not only can it provide a distraction, but it can also alleviate boredom which in itself can create or exacerbate anxiety \- see also, Csikszentmihalyi (2000).

As NoPanic.org points out, you should...

> do something that makes you happy. Every day should include a bit of ‘ME’ time. It may be losing yourself in a book, playing or listening to music or a self-pamper session. However busy life seems, you deserve that special time.

## References

Csikszentmihalyi, M. (2000). *Beyond boredom and anxiety* (Vol. 721). San Francisco: Jossey-Bass.
> 4 votes

# Answer
What you are describing sounds a lot like aspects of Occupational Therapy (sometimes called Ergotherapy). Occupational therapy can include prescribed activity such as knitting (to meaningfully occupy your time) and is applied to a wide range of health related issues including anxiety.

Here is a dictionary definition of Occupational Therapy https://www.merriam-webster.com/dictionary/occupational%20therapy

And here is a link to a definition from the University of British Columbia https://osot.ubc.ca/about/what-is-os-ot/
> 2 votes

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Tags: cognitive-psychology, behaviorism, stress, anxiety
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# Question
Title: What are existing theories on competing wills in the mind?
To clarify a little further, I've read in different places that our brain could be composed of mini minds, that preform all sorts of actions. Assuming this is valid I'd think that of these minds, some result in a composite or layering that results in our personality and an ultimate will that wins out to complete some action or decision, insomuch as a set of minds are inter-related in relation to some function.

I'm really just assuming from reading various articles and papers and some personal self reflection... but I'd imagine there is something to read in relation to this idea in some shape or form.... In other words I'm looking for more solid reading material, I'm not sure what I should be searching for.

# Answer
> 1 votes
Instead of pointing you to existing theories, which is (1) too advanced for you to understand at the current level of knowledge, and (2) too focused so that you don't have a big picture, why don't we just suggest you to read a textbook about cognition? It will solve both problems at the same time.

I recommend the book **Cognitive Psychology**, written by Strenberg, as the starting point. **Cognition: Exploring the Science** (author: Reisberg) is also a good one. If you are like me, you will realize how to make the question clearer just after some first few pages of reading.

# Answer
> 0 votes
Two theories that can elaborate on your initial question would be:

1. Norman and Shallice model on executive function. Specifically the component described as supervisory attentional system:

Norman, D. A., & Shallice, T. (1986). Attention to action. In Consciousness and self-regulation (pp. 1-18). Springer, Boston, MA.

2. Leon Festingers concept of cognitive dissonance:

Festinger, L. (1962). A theory of cognitive dissonance (Vol. 2). Stanford university press.

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Tags: cognitive-psychology, cognitive-neuroscience, reference-request
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# Question
Title: What kind of psychologists study 'genius'?
Which sub-field of psychology deals with differences in human intelligence? As in, what makes someone an intellectual genius? Or, maybe a bit more humbly, why are some people more intelligent than others? It would help if you could also mention some leading thinkers in this field (or any good resources to read more about these topics)

Thanks!

# Answer
> Which sub-field of psychology deals with differences in human intelligence? As in, what makes someone an intellectual genius?

Broadly speaking, the study of individual differences in psychology is called *differential psychology*. *Psychometrics* is the study of psychological measurements, an extremely important part of intelligence research.

> Or, maybe a bit more humbly, why are some people more intelligent than others?

The subfield that has been most important in establishing why some people are more intelligent than others is probably *behavioural genetics*. This field has been at the forefront of creating experimental designs that can give evidence for the causes of individual differences.

However, these fields overlap. It can sometimes be difficult to difficult to say when something is research in field X or Y (And often not important exactly which field you would categorize it as).

> It would help if you could also mention some leading thinkers in this field (or any good resources to read more about these topics)

There are many important researchers who study intelligence and why people differ intellectually. Here are a few examples of books that talk, in part, about why people differ in intelligence.

(1) "Intelligence" by Stuart Ritchie. This is a short introduction to intelligence research and is easy to read.

(2) "The Neuroscience of Intelligence" by Richard Haier. This book is slightly longer, but is still fairly easy to read. This book focuses on the actual brain itself.

(3) "The *g* Factor" by Arthur Jensen. This is a more detailed and complex book. It's not as new as the others but is considered a classic.

However, if you're talking specifically about high intelligence then there are only a few leading researchers.

There have been several leading figures if you go far enough back. All the way from Francis Galton to Lewis Terman to Julian Stanley. Two of the most important current researchers are David Lubinski and Camilla Benbow. They are leading the Study of Mathematically Precocious Youth (SMPY), which is a longitudinal study of highly intelligent individuals. See the link for several publications from the study.

If I could give only a single article (on the subject of very high intelligence) for you to read, it would be the following:

Lubinski, D. (2016). From Terman to today: A century of findings on intellectual precocity.

This is a review of the findings of the study of highly intelligent individuals.

There are other researchers that are important, of course. One other I know who researches high intelligence and high achievement is Jonathan Wai, see his blog if you interested. I'm sure other people could refer to several other important researchers.
> 1 votes

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Tags: personality, intelligence
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# Question
Title: complex name - surrounding you with inferior (less talented) people
What is the name of the complex of surrounding oneself with inferior (less talented) people to avoid being eclipsed or overcome?

I have a vague memory that it was a Greek naming or one from classic literature, but I cannot conjure it up.

# Answer
> 2 votes
It's not greek, but... Wills classified this as a group behavior, and called it downward social comparison. The gist of the theory is that a person attempts to feel better about him-/herself by socializing and comparing with someone considered performing poorer in areas important to him/her.

Wills, T. A. (1981). Downward comparison principles in social psychology. Psychological Bulletin, 90(2), 245-271.

# Answer
> 1 votes
Could the OP be refering to hubris?

> Typically, overconfidence led the hero to attempt to overstep the boundaries of human limitations and assume a godlike status, and the gods inevitably humbled the offender with a sharp reminder of his or her mortality.
>
> To the Greeks, hubris referred to extreme pride, especially pride and ambition so great that they offend the gods and lead to one's downfall. Hubris was a character flaw often seen in the heroes of classical Greek tragedy, including Oedipus and Achilles. The familiar old saying "Pride goeth before a fall" is basically talking about hubris.

Related, see Superiority Complex, and Dunning-Kruger effect.

# Answer
> 1 votes
From the Wikipedia page

> Narcissism is the pursuit of gratification from vanity or egotistic admiration of one's idealised self image and attributes. The term originated from Greek mythology, where the young Narcissus fell in love with his own image reflected in a pool of water.

As to surrounding themselves with inferiors ... well at least in there own eyes they do.

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Tags: psychology
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# Question
Title: Can you really have "excessive empathy"?
This question arose out of the question Excessive empathy, social cues and adaptive behavior evaluation whereby excessive empathy was considered to impair interpersonal relationships. My question is asking if you can actually have too much empathy.

Empathy, **not to be confused with sympathy** is

> the capacity to understand or feel what another person is experiencing from within their frame of reference, that is, the capacity to place oneself in another's position (Bellet & Maloney, 1991).

When empathising, you can actually feel the emotions the client is feeling, and you need to be able to compartmentalise these feelings by recognising that they are not yours to own. They are not your feelings, they are the client's feelings. In the psychological fields, they are there to help you to recognise congruency within the client (is the feeling the client expresses, the feeling the client should have?).

As I pointed out in my comment in Excessive empathy, social cues and adaptive behavior evaluation,

> the need to break away **at times** is self-care

The moment you take on the feelings your client has, this is the moment where you are not exercising self-care.

Empathy is a necessity when working within the therapeutic environment and as Bellet & Maloney (1991) points out, it is important within the field of medicine. Therefore, self-care is paramount to practitioner wellbeing within the relevant fields, as I highlighted in my answer to Named conditions that are the result of exposure to psychopathic behavior of another person? to protect against instances of vicarious trauma caused by environmental psychological conditions.

When looking online, there is a PsychologyToday article (Reynolds, 2017) which proposes that you **can** have too much empathy but I have a problem following her train of thought on her hypothesis.

> With empathy, you will feel their stress, anxiety, and anger in your body. You might feel their pain emotionally and physically. If you let these emotions sit in your body, your body and mind can be emotionally hijacked.
>
> Unbridled empathy can lead to concentrations of the stress hormone cortisol, making it difficult to release the emotions. Taking on other people’s feelings so that you live their experience can make you susceptible to feelings of depression or hopelessness.

With this passage, there was a citation for:

> Blaszczak-Boxe, A. (2017) Too much emotional intelligence is a bad thing. *Scientific American Mind* \[Online\] Retreived from: https://www.scientificamerican.com/article/too-much-emotional-intelligence-is-a-bad-thing

My argument to Reynolds (2017) is that she is describing lack of self-care (lack of compartmentalisation), not excessive empathy, leading to mental health problems within the therapist.

Am I missing something or can there be such a problem as "excessive empathy"? If so, how much empathy is excessive and how would you be able to recognise this excess?

## References

Bellet, P. S., & Maloney, M. J. (1991). The importance of empathy as an interviewing skill in medicine. *Jama, 266*(13), 1831-1832. doi: 10.1001/jama.1991.03470130111039

Reynolds, M. (2017). Too Much Empathy?: When empathy breaks instead of builds trust. *PsychologyToday* \[Online\] Retreived from: https://www.psychologytoday.com/gb/blog/wander-woman/201704/can-you-have-too-much-empathy

# Answer
> 3 votes
The risks of excessive empathy is sometimes conceptualized as "compassion fatigue" or "vicarious traumatization". The problem is not necessarily considered an excess in empathy, it can also be described as an excess in work load.

What could be considered excessive is most likely individual, not unlike our capacity for handling other types of work, like lifting heavy loads or work long hours at the office, for instance.

The most reliable measurement i can think of is how much time a day we spend working as a therapist, for lack of better constructs. Another example for conceptualizing excessive empathy would be the prevalence of fatigue/secondary ptsd symptoms.

Also i'd be curious to see how therapists ambitions/expectations on therapy outcome factors into the risk of compassion fatigue. I don't believe such research has been made.

More research is needed for sure.

https://proqol.org/CS\_and\_CF.html

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Tags: social-psychology, emotion, empathy, emotional-intelligence
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# Question
Title: What benefit is responsible for human preference of one food over another?
I like kiwi. I don't like omelettes. I love berry pies, but I'm not a big fan of potato chips or pretzels.

Human taste preference is seemingly universal, with even young children able to identify foods that they like and dislike, and react appropriately, hungrily seeking the former and rejecting the latter.

But what evolutionary purpose does this serve? Is my dislike of potato chips and pretzels a sign that my body is somehow predisposed to excess sodium, and this distate for the food a compensation mechanism? Is my love of kiwi an indicator of some deficit, perhaps of vitamins C and K, or my more general preference for sour flavors (which tend to indicate acidity) a part of pH regulation?

At its heart, does biological need or deficiency for particular components of a food explain personal preference for that foodstuff, and if not, is there research showing what does?

# Answer
Reasons why we do or do not like certain foods:

**1. Taste**

I may want to eat foods *that taste pleasantly:* chocolate, cakes, fried chicken and...sweet cabbage (?!).

**2. Bowel regularity**

I discover that whole-grain bread makes wonders to my bowel regularity, which *makes my stomach to feel good,* which overweights a bit bitter taste of such bread in my mouth, so I start to like it.

**3. Health concerns**

I read that fast food may not be healthy, so I stop eating it and *start to feel better in general,* and, with time, I will *actually* stop liking fast food.

**4. Nutrient deficiencies**

If I have a period in which I eat very few plant foods, I'll start to crave things, like green salad. I believe, I can start craving foods that contain certain minerals and vitamins I'm missing (iron, potassium, vitamin C, protein...).

**5. Medical conditions**

**6. Beliefs**

I can just *hear or believe* that certain food is "not good to eat" or "not good for me" and, just because of this, I might find that food disgusting.

**7. Genetics and environment**

Genetic and environmental factors can influence food preferences, especially in children and adolescents (PubMed, 2016).

**8. Depression**

Depression can be associated with craving for foods high in carbohydrates and fats, such as chocolate and chips (PubMed, 1995).

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**In conclusion:** Nutrient deficiencies can be one of the factors for food preference.
> 1 votes

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Tags: perception, preferences
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# Question
Title: Can a device create/guide neuron connections between them?
Is there a device of some sort that could promote/guide/create exact connections between neurons? I wish there was a device that could get me PhD by just wearing it for a few months.

# Answer
You can't get a PhD using an electronic device, that's the stuff for movies (Fig. 1). Plus, as I claim in my profile, there's a lot more to science than learning new material:

> Behind the great achievements of a Gauss or an Einstein is in all cases a life devoted to contemplation, curiosity, collaboration and, perhaps most of all, hard work (Burrell, 2015).

However, to bring your question down to a more elementary level, there are concepts in development to guide neuronal growth toward certain targets, for example for use in cochlear implants (CIs). CIs stimulate the inner ear in people with severe hearing impairment. A CI basically consists of an array of electrodes that is guided into the inner ear. Because the electrode contacts are situated relatively far from the target neurons (spiral ganglion cells making up the auditory nerve, see Fig. 2), scientists have been contemplating how to bring the source closer to the target. One way to (theoretically) do this is to coat the electrode array with a solution releasing neurotrophic factor(s), such as BDNF(*e.g.*, Ramku *et al*. (2017)). These compounds are known to act as chemo-attractants that can stimulate and guide neural outgrowths.

Fig. 1. Reaves learning Kunf Fu. source: EJ4

Fig. 2. CI. source: Debener (2016)

**References**
**-** Burrell, *Sci Am*, September issue 2015
**-** Debener, Cortical plasticity in cochlear implant users (2016). Thesis
**-** Ramku *et al*., *Open Access Maced J Med Sci* (2017); **5**(2): 121–5
> 2 votes

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Tags: neuroscience, eeg, neurophysiology
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# Question
Title: Why it is so difficult to think critically about family members behaviour?
It seems to me that some survival mechanisms working in us make the act of analyzing family members behaviour very difficult. We tend to perceive the family's behaviours as normal, even if there are not. In my experience, we must achieve a high level of detachment from the family to be able to think critically.

So my question is, what are our mechanisms that makes it so difficult to think objectively about family members' (aberrant) behaviours?

# Answer
**Short answer**
Millions of years of evolution have resulted in increased empathy towards family members.

**background**
I may be taking a big leap here, but I think the roots of the family-related tolerance may be ingrained in our very genes.

In an interesting article by Tomasello (2018) he hypothesizes that collaboration was among the key features that resulted in the separation of the *homo* lineage from the apes, starting around 2 mln years ago. Homo heidelbergensis (400k years ago) is believed to have actively collaborated when foraging for food. This collaboration became compulsory, as individuals became dependent on one another to obtain their daily food. Tomasello hypothesizes that morality and empathy were born out of this interrelationship, which helped to sympathize and help their partners. The partners learned to cooperate in hunting (one would chase, the other spear the animal). A "we is greater than me" kind of morality was born.

Then, 200k years ago, modern *homo* was born, an era characterized by competition between small, closely knit groups for food and other resources This meant that members of such a group would have to collaborate and protect each other against invaders. Often (but not always) there would be kinship involved in these small groups ('tribes'). Tomasello continues that this collaboration eventually resulted in the development of culture, but that's outside the scope of this answer.

In all I think I would conclude that millions of years of evolution have resulted in increased empathy towards family members.

<sub>**Reference**
**-** Tomasello, *Sci Am*, September issue 2018</sub>
> 0 votes

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Tags: perception, behavior
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title: Bottom up thinking - what is it?

text:
# Question
Title: Bottom up thinking - what is it?
Mlodinow has book Elastic thinking, which sounds interesting and where he mentions bottom up processes/thinking; which he equates with elastic thinking.

I have watched numerous videos about it, and even read some sample chapters of the book - but to my surprise, it is still unclear to me what exactly he means by **bottom up thinking**?

One unclear quote from the book is:

> Elastic thought is where your new ideas come from. Imaginative, original, and non-linear, it is “bottom-up” thinking, in which insights percolate into the mind, seemingly from nowhere.

Another unclear quote:

> Elastic thinking is about stretching your mind and using ‘bottom up’ processing in the brain rather than the top down executive functions that drive analytical thinking

Can someone please bring **some simple and concrete examples from daily life**, of what is bottom up thinking?

ps. His book is based on research and says it is known term in science community, this elastic thinking/bottom up thinking, and hence my hope people here may know what is it.

# Answer
> 2 votes
Hutchinson, B. (2002), an article in the book *Synergy Matters* by Adrian M. Castell may help in understanding what is meant by *bottom up thinking* and the opposite, *top down thinking*.

> \[T\]he term ‘top down’ is used to describe an approach to problem solving where the problem space is defined first. The worldviews of the participants are used to conceptualise the desired state of the proposed system. Once this is achieved, the system is developed within this boundary. The components, or subsystems are derived within the context of the predefined desired state. The term ‘bottom up’ is used to describe an approach where no assumptions are made about the boundary of the problem space. The behaviour of component parts are rationally observed to determine the properties they have. Management decisions, or system designs are then based on the observed behaviour of components.

An example given in the conclusions is:

> \[I\]nvestigating a system failure in bottom up mode would look for causes at the element level, or more precisely, at their interactions. The top down mode would tend to look at the overall system, and would put ‘blame’ on the system itself and how it functions, rather than emergent properties of system element interactions.

Think of it like a brick building. You need to build it from the bottom up, with each brick being correctly placed to form the correct shape etc. If the bricks are placed differently, you may get a different building, or maybe you will get the same building but badly constructed.

Take the following as a more detailed example comparison...

There is a team of researchers working on a task and each member inputs their findings into a computer system which analyses the results and comes up with a conclusion.

The program relies on accurate information from each team member entry but there was a slight error in a couple of entries producing an incorrect conclusion by the system.

A top down thinker would blame the computer system analysing the results. A bottom up thinker would analyse what the system was analysing and how, leading to them finding the real cause.

## References

Hutchinson, B. (2002). Bottom up thinking. In *Synergy Matters* (pp. 445-450). Springer, Boston, MA. doi: 10.1007/0-306-47467-0\_75
Preview available in Google Books

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Tags: cognitive-psychology, neuroscience, evolutionary-psychology, unconscious
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# Question
Title: Can the brain be enhanced by adding more neurons?
I was wondering of ways to enhance the brain. Couldn't we add a sort of substance to improve the brain? Will it somehow adapt? The brain should 'wire up' the new substance to the existing one.

As far as I know, the brain is just neural connections, so why just not add more connections? I mean, why not add more neurons, therefore enhancing the human mind, getting closer to answering questions like "Does God exist?".

Maybe modifying DNA to produce more neurons, making the brain bigger...? In my opinion the future lies in enhancing the mind, what ways are there to do that?

P.S - I'm only 16 y/o.

# Answer
> 4 votes
I'll try to tackle this question from a developmental vantage point.

You hit the nail on the head by saying

> ...the brain is just neural connections...

Indeed, the power of the brain is based on the connectivity of its neurons. The number of connections is what counts, not just absolute neuronal numbers. In fact, **more than 50% of neurons are lost during development**, as a result of limiting trophic support from the target tissue they are destined to innervate. This neuronal cell death facilitates proper connections in the nervous system. The apoptotic cells are indeed unwanted in the nervous system, and apoptosis continues throughout life and is the central mechanism for the removal of surplus, unwanted, damaged or aged cells. (Mazarakis, 1998). Leaving them could result in aberrant functionality. For instance, it is claimed that synesthesia *may* be linked to incomplete neural cell death in development, leading to aberrant connections between the senses. Many sysnesthetes for instance see certain numbers appear in specific colors. These cross-sensory associations are thought to be caused by faulty cell death between the respective sensory systems in the central nervous system (the brain).

In effect, adding neurons to an existing functioning brain is expected to lead to disruptive brain function, rather than improvement.

The practical limitations of injecting additional neurons are mountainous -

* Where would you obtain viable neurons from? Stem cells?
* In the case of stem cells there's a chance of uncontrolled growth (cancer);
* If the neurons don't come from a genetic identical individual there's the issue of immunological graft rejection;
* How would you deliver the neurons to their appropriate position in the brain? Just drill a diffuse set of holes in the skull? How would you reach the deeper layers of the brain? How would you contain the neurons to the brain and prevent 'leakage' to unwanted sites in the body, such as the blood stream?

<sub>**Reference**
**-** Mazarakis, *Archives Disease Childhood* (1997); **77**:F165–F70</sub>

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Tags: neuroscience, neurophysiology, brain, cognitive-enhancement
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# Question
Title: Are neural adaptation and drug tolerance to psychoactive drugs related?
Neural adaptation is "...a change over time in the responsiveness of the sensory system to a constant stimulus". The example given is placing your hand on the surface of a table. Eventually, you no longer sense your hand touching the table because your neurons have adapted to the stimulus.

Drug tolerance is "...reduced reaction to a drug following its repeated use". This means that increased dosages are required to produce the same effect. I've been careful to state that the drugs I'm considering are psychoactive drugs, so their mechanism of action of is mostly within the brain.

The missing link between these two concepts seems to be acclimatization. Acclimatization is "the process by which the nervous system fails to respond to a stimulus, as a result of the repeated stimulation of a transmission across a synapse". The article on neural adaptation states that acclimatization is the process by which neural adaptation is usually believed to occur.

So is drug tolerance a form of neural adaption with the stimulus being whatever substance a subject repeatedly consumes? It's worth noticing that adaptation does not specify a direction of change in responsiveness. Therefore, assuming drug tolerance is a form of neural adaption, and if the effects of exposure to drugs become amplified rather than diminished, it too would be a form of neural adaptation.

Links to sources in order of appearance:

# Answer
Drug tolerance can be generally defined as

> A condition that occurs when the body gets used to a medicine so that either more medicine is needed or different medicine is needed.

Tolerance to drugs can be produced by several different mechanisms.

* In the case of morphine or heroin, tolerance develops at the level of the cellular targets. Activation of opiate receptors triggers the inhibition of the enzyme adenylate cyclase. After repeated receptor activation, adenylate cyclase adapts so that the morphine can no longer cause changes in cell firing (source: NIH).

However, stating that a single target is involved is definitely an oversimplification.

Another NIH report on ethanol dependence gives an awesome comprehensive overview of the bewildering complexity behind this phenomenon, and I will only shortly sum up the different mechanisms stated there:

* **Functional Tolerance** develops due to brain adaptations that compensate for the alcohol. Chronic heavy drinkers show few obvious signs of intoxication even at blood alcohol concentrations (BAC's) that would otherwise be considered fatal. Examples of functional tolerance are the following:
* **Acute tolerance** can be observed within a single drinking session. Alcohol-induced impairment is greater when measured soon after beginning alcohol consumption than when measured later in the drinking session.
* **Environment-dependent tolerance** develops over several drinking sessions and is accelerated if alcohol administration is always in the same environment, for instance in the local pub.
* **Learned tolerance** develops by practicing a task while under the influence of alcohol. Rats develop tolerance faster in the context of maze walking when they have been when walking in a maze under influence for instance that practiced the task while under the influence of alcohol than rats practicing without prior alcohol administration. Likewise, people develop tolerance more rapidly if they practice a task while under influence, for instance on an eye-hand coordination task. w
* **Environment-independent tolerance** needs larger doses.
* **Metabolic tolerance** results from a more rapid elimination of alcohol from the body and is caused by the upregulation of liver enzymes that metabolize alcohol. Enzyme activation increases alcohol degradation and reduces the time during which alcohol is active in the body, thereby reducing the duration of alcohol's intoxicating effects.

The metabolic tolerance is the easiest to comprehend, but the environmentally-dependent tolerance and learned tolerance, for instance, are definitely centrally mediated, but not just by one simple molecular mechanism, but by the interplay of complex neural networks governing complete and complex associations and tasks.

<sub>**Source**
**-** National Institute on Alcohol Abuse and Alcoholism</sub>
> 2 votes

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Tags: neuroscience, neurophysiology, psychopharmacology, drugs, adaptation
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