# Question
Title: Is there a waterfall visual after-effect with discrete inputs?
If you watch a waterfall for several seconds and then suddenly change your gaze to a fixed object it appears to briefly move upward.

But if instead you're looking at a scrolling LED marquee sign, does the motion aftereffect still take place? In reality nothing is actually moving on the marquee sign because the LEDs are all fixed in place.

The answer to this question probably has interesting implications as to where in the visual pipeline motion is being processed. The difference between the actual waterfall and the scrolling LED marquee might also be a good way to separate out various aspects of motion processing. I'd be curious in hearing commentary on this.

# Answer
> 2 votes
The waterfall after-effect is an illusion falling into a broader class of visual illusionary apparent movements caused by watching a constant motion for an extended period of time. The **motion after-effect** can be explained by adaptation of visual neurons that respond selectively to movement. Motion-sensitive visual neurons are tuned to a specific direction. Exposure to a continuous motion in one particular direction fatigues specifically those visual neurons that are tuned to that direction as they continuously fire. When the visual stimulus stops, it alters the balance of activity in favor of cells tuned to the opposite direction, as these are the least fatigued by the stimulus and this causes the after-effect (Mather *et al*., 2008).

The motion-after effect does work well with more discreet stimuli too.

To start with, here is an example of a more standard waterfall effect illusion (see Fig. 1 for a related impression still image).

Fig. 1. Waterfall. source: Carlos Vasquez

And in this video an example is shown of the waterfall after effect with more discreet stimuli. Not particularly your standard marquee sign but it comes close and there's a definite motion after effect observable (Fig. 2).

Fig. 2. Movie still from this video

However, I think your question is specifically whether a motion after-effect occurs with chase-lighting as often seen in Marquees signs (Fig. 3).

Fig. 3. Marquees sign showing illusionary apparent motion. source: Old Turnpike School

The **chasing-light stimulus in itself is a visual illusion**, as there **is no true motion involved**. Instead, it is generated by using electronic circuitry to activate lights serially with a certain time delay in-between activations. Because there is no motion involved as such, I believe the after effect will not occur, or very weakly. At least, I couldn't observe an after effect after watching several chase lightings for a while. For example, the chase lightings in Fig. 1 become ambiguous when I look at it a while, *i.e.*, the lights actually spontaneously reverse their direction when staring at it for a while. The only thing I see when I look away, personally, is a colorful blob, and no motion after-effect.

**Reference**
**-** Mather *et al*., *Trends Cog Sci* (2008); **12**(12): 481-7

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Tags: perception, vision, neurophysiology, optical-illusion
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# Question
Title: Is there a validated questionnaire on consumer well-being?
I am conducting a study comparing different cigarettes in terms of their relative toxicity. As a side analysis, I wish to see if a novel cigarette, purportedly less toxic, is similarly pleasurable.

Participants will only smoke one cigarette, so I would like to use a validated questionnaire of instantaneous well-being and satisfaction. Are there any?

# Answer
> 1 votes
There are many consumer satisfaction tests available, see for a somewhat dated but informative review Westbrook & Oliver (1981). Most often, simple, single-item rating scales are employed. Reportedly, there is little uniformity in the number of scale steps used and in the anchoring. They often range from 3-point labeled rating scales (*e.g.*., good - neutral - bad) to 10- and 11-point variants labeled only at the extremes and midpoint (*e.g.*, 0= bad; 5 = neutral; 10= excellent).

An interesting consumer questionnaire I found was devised by Lou *et al*. (2007). It was devised for assessing people's satisfaction with drinking water and consisted of a general part I with personal information (Fig. 1), and a part II specifically testing consumer satisfaction (Fig. 2). Because the authors targeted specifically the defining characteristics of drinking water based on the Water Taste and Odor Wheel you might want to adapt certain questions in part II to match your specific needs.

Fig. 1. Part I. General information. source: Lou *et al*. (2007)

Fig. 2. Part II. Consumer satisfaction. source: Lou *et al*. (2007)

**References**
**-** Lou *et al*. *J Environmental Management* (2007); **82**(1): 1-12
**-** Westbrook & Oliver, *Advances Consumer Res* (1981); **8**: 94-99

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Tags: perception, reference-request, methodology, test, well-being
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# Question
Title: Can we identify specific emotions on the basis of fMRI scans?
I am looking for fMRI studies in which the emotional response of a person listening to music is visible in the fMRI scans, paralleled by a retrospective think aloud report of the person describing his/her emotions while listening. Are there such studies? And did they reveal something comprehensible, i.e. can one see in the fMRI scans how emotions did manifest themselves?

The idea is, that one might be able to distinguish between emotional responses due to characteristic activity patterns or modes, perhaps including the amygdala.

I know of this video with Oliver Sacks being the person, but it disappointed me: we only see that he is emotionally touched stronger by Bach than by Beethoven. But - as I have the impression - we cannot distinguish between positive and negative emotions by just looking at the fMRI scans, can we?

# Answer
> 5 votes
From meta-analyses that include musical emotion inductions, there is not much evidence that we can reliably distinguish between emotions in the brain, independent of the emotion induction procedure or meta-analytical method (    ).

We might be able to distinguish emotions with specificity and reliability within an individual, but this kind of work is just starting to happen.

# Answer
> 2 votes
**Short answer**
Pleasant and unpleasant music activate other areas of the cortex, potentially allowing for differentiation of music-related emotions based on fMRI scans alone.

**Background**
An fMRI study by Koelsch *et al*. (2009) investigated human emotions evoked by pleasant (consonant) and unpleasant (dissonant) music.

Unpleasant music activated the...

* amygdala
* hippocampus
* parahippocampal gyrus and
* temporal poles.

These structures are generally implicated in negative emotions.

In contrast, pleasant music activated the...

* inferior frontal gyrus (IFG)
* anterior superior insula
* ventral striatum
* Heschl's gyrus
* Rolandic operculum.

IFG activations appear to reflect processes of music–syntactic analysis and working memory operations. The operculum, anterior superior insula, and ventral striatum are thought to be part of a pre-motor circuit for vocal sound production during the perception of pleasant sounds.

<sub>**Reference**
**-** Koelsch *et al*., *Human Brain Mapping* (2006); **27**(3): 239–50</sub>

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Tags: cognitive-neuroscience, emotion, neuroimaging, fmri, brain
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# Question
Title: Working Memory Timing Information Storage
In most working-memory tasks, a person is given a list and is asked to recall it in various manners. For example, they could recall it forwards, backwards, freely or try to recall a specific item given it's position.

However, has there been any tests where temporal information is emphasized? For example, consider the scenario where there is 1 second between the presentation of the first and second item in the list, but 2 seconds between the second and third items in the list. I could then ask the person which item was temporally closer to the second item in the list.

Has there been any Working Memory research of this temporal nature?

# Answer
In "Similarity Breeds Proximity: Pattern Similarity within and across Contexts Is Related to Later Mnemonic Judgments of Temporal Proximity" by Youssef Ezzyat and Lila Davachi, timing between stimuli was kept constant, but the context of the stimuli was manipulated.

They found that changing contexts increased the perceived temporal distance between stimuli.

Alternatively, in "Learning and Generalization of Auditory Temporal–Interval Discrimination in Humans" by Wright et al., differentiating temporal distance between tones were learned. Additionally, in "Anticipation of future events improves the ability to estimate elapsed time" by Yoshiaki Tsunoda and Shinji Kakei, the probability distribution of distance between a warning signal and a trigger for a "GO"-like task was learned.

These experiments operate on very different time scales (milliseconds vs seconds) with very differently semantically-loaded stimuli (images vs tones). Although neither of them describe in the exact experiment in the original question, together they show the various ways perception and memory is affected temporal cues.
> 2 votes

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Tags: cognitive-psychology, reference-request
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title: Ligand-gated ion channels as operators

text:
# Question
Title: Ligand-gated ion channels as operators
Isn't there a perfect analogy between ligand-gated and voltage-gated ion channels considered (mathematically) as (non-linear) operators, mapping one function (of time) to another one? Voltage-gated channels respond to voltage *signals* (= functions of time at a given location, not just a voltage), ligand-gated channels respond to neurotransmitter *signals* (not just neurotransmitters). Both yield a conductance *profile* (as a function of time, not just a conductance).

Both ligand- and voltage-gated ion channels display some form of hysteresis, i.e. the dependence of the state of a system on its history. Hysteresis can not be modelled by simple mathematical functions (by which dependencies normally are modelled), but maybe better by some non-linear operators.

With respect to the Hodgkin-Huxley model (that AliceD mentions in her answer): In this model (that is also used by Rall) the resistances (= ion channels) are just switched on and off instantaneously. But this may be oversimplified: it takes some time, and it cannot be done with arbitrary frequency. That's why we possibly need operators to describe them.

My question is: Are there references where ligand-gated channels are modelled mathematically as (non-linear) operators?

# Answer
**Short answer**
Generally, Hodgkin & Huxley-derived models are used to describe the gating characteristics of ion channels and ligand operated receptors.

**Background**
Ligand-gated and voltage-operated ion channels do not really perform a memory task. Instead, they channel ions across the cell memnrane and by doing so they can convey information from out the cell (neurotransmitter release / voltage changes) into the cell. Their role is physiological and the way they are modeled is typically based on **Hodgkin & Huxley kinetics** (Sig, 2014) (Fig. 1).

Fig. 1. Hodgkin & Huxley model of membrane kinetics. source: Neuronal Dynamics

The Hodgkin-Huxley model models the semi-permeable cell membrane as a capacitor that separates the interior of the cell from the extracellular fluid. If an input current is injected into the cell, it may add further charge on the capacitor, or leak through the channels in the cell membrane. Each channel type is modeled by a resistor (conductor of current). The unspecific channel has a leak resistance R, the sodium channel a resistance RNa and the potassium channel a resistance RK. The diagonal arrow across the diagram of the resistor indicates that the value of the resistance is not fixed, but changes depending on whether the ion channel is open or closed. Because of active ion transport through the cell membrane, the ion concentration inside the cell is different from that in the extracellular liquid. The Nernst potential generated by the difference in ion concentration is represented by a battery. The Nernst potential depends on the ion and hence there are separate batteries for sodium, potassium, and the unspecific third channel, with battery voltages ENa, EK and EL (source: Neuronal Dynamics).

Now to your edited question: you say

> \[Ion channels\] are just switched on and off instantaneously. But this may be oversimplified: it takes some time...

It goes further than that; voltage-operated ion channels like the Na+ channel are actively activated and inactivated with well-defined time constants that, among other things, govern the process of absolute and relative refractoriness of nerve cells (Fig. 2). The temporal gating characteristics in terms of activation and inactivation are expressed as time constants, which can be described in for example a **Markov model** (Wang *et al*., 2004). For example,

dm/dt = 1/τm(V) * (m∞(V)−m), where

m∞(V) = α(V) / \[α(V)+β(V)\] (9) τm(V) = 1 / \[α(V)+β(V)\]

Here, m∞ is the steady-state activation and τm is the activation time constant of the Na+ current (n∞ and τn represent the same quantities for the K+ current). In the case of h, h∞ and τh are called steady-state inactivation and inactivation time constant, respectively (source: Destexhe & Huguenard, 2007).

Similar formulas apply to the association and dissociation constants in ligand-operated channels, where timing of activation and inactivation are affected by the ligand's affinity for the receptor.

Fig. 2. Ion channel gating. source: Lehmann-Horne & Jurkatt-Rott (1999)

**References**
**-** Lehmann-Horne & Jurkatt-Rott, *Physiol Rev* (1999); **79**(4): 1317-72
**-** Sig, *J Gen Physiol* (2014); **144**(1) 7-26
**-** Wang *et al*., *J Physiol* (2004); **557**(3): 705–17
> 2 votes

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Tags: memory, reference-request, theoretical-neuroscience, neurophysiology, short-term-memory
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# Question
Title: Which Cognitive Sciences are the most affected by the Replication Crisis?
As many here are probably aware, a replication crisis seems to have been occurring in many scientific fields for some time now. Allegedly, Psychology is at the center of this crisis, with many of its high-profile studies turning out to be impossible to replicate.

As someone who tries to regularly consume academic literature in order to educate oneself, this makes me wonder what areas within the broader umbrella of 'Cognitive Sciences' have had the most replication attempts fail and/or have the most information available about replication failures.

# Answer
> 8 votes
One finding from the Reproducibility Project was the following:

Van Bavel et al wrote that

> Inbar (2) notes that the reproducibility rate of social psychology (28%) is lower than cognitive psychology (53%).

In general, one might expect that subdisciplines with the following features to have greater reproducibility issues:

* particularly interested in novel effects
* many researcher degrees of freedom (e.g., analytic choices, many possible outcomes variables, many possible predictors, etc.)
* between subjects designs rather than repeated measures designs
* lower statistical power (typically because getting a sufficient sample size requires substantial resources)
* those embracing fewer open science practices (e.g., pre-registrration, open data, etc.)

So, for example, cognitive psychology often uses repeated measures designs to examine fairly intuitive cognitive effects.

Personality and individual differences research is often concerned with quantifying the degree of relationships and often has very large sample sizes.

A lot of neuroscience research traditionally used techniques like fmri that often involves many researcher degrees of freedom (e.g., many brain sites), and the research is expensive per participant so sample sizes are often too small.

Social psychology has a tradition of being interested in novel experimental effects. Many of these studies have traditionally been underpowered (e.g., 20 or 30 participants per group, when perhaps 100 or 200 per group would be required for adequate power), and they have often had some degree of flexibility (e.g., choice of outcome variable; case exclusion rules; whether to transform; whether to covary for something; etc.).

These effects also combine with publication bias (preferences to publish significant effects) and file draw effects to reduce replication (although the same bias reduces the awareness of these issues).

That said, in general, a lot is happening in the open science area to try to both increase understanding of replication issues, as well as change research practices.

Reference

* Van Bavel, J. J., Mende-Siedlecki, P., Brady, W. J., & Reinero, D. A. (2016). Contextual Sensitivity Helps Explain the Reproducibility Gap between Social and Cognitive Psychology.

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Tags: reproducible-research
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# Question
Title: How to understand what a low score or high score is for a particular measure?
I am trying to use a survey tool to recommend a particular decision. In my case, I am using the Ten-Item Personality Inventory (TIPI; link here: https://gosling.psy.utexas.edu/wp-content/uploads/2014/09/JRP-03-tipi.pdf) and want to understand what a good binary or ternary cut off would be to recommend a choice. Should I use the mean score or 33% percentiles respectively or is there a better way to think about it? Also, more generally when taking a survey test, how do you recognize if you are "low," "average," or "high" on a particular measure? For instance, when you take a personality test and your results state you are low in neuroticism, where does that ordinal value come from?

Lastly, it should be useful to note that from the research paper I linked, I don't yet know the mean values/percentiles, so if that is the right answer, using an example referencing the paper would be most beneficial to my problem.

# Answer
First, a minor point is that the TIPI is a very poor measure of individual-level personality. Two item measures of personality are rarely justifiable. Standard errors of measurement are unnecessarily large.

In general, you are talking about the topic of norms and standardized scores. Any introductory book on psychological measurement will discuss topics related to standardised scores and norms.

General thoughts about defining a high and low score:

### 1. **Define your population.**

You need to define your target population. E.g., Just males? Just females? What ages? What country? etc.

### 2. Obtain estimates of norms for that population.

You then need to get a sample estimate of that population. In some cases, the test manual may provide this. In other cases, you can look to the published literature to see various normative samples.

### 3. Calculate statndardized scores

You then need to compute a standardized score that relate an a particular respondent's score to the norms. Percentile ranks are one way of doing this. Other approaches are based on z-scores (i.e., where the raw score is scales to mean of zero and an standard deviation of 1). For example, t scores are the same as z-scores, but mean is 50 and standard deviation is 10. https://en.wikipedia.org/wiki/Standard\_score

Note that these standardized scores are always contingent on your norm sample.

There are also a range of more sophisticated approaches that are sometimes applied. For example, if you are doing cognitive testing in children, you can interpolate norms between ages, so for example, the norm for a 6.5 year old is different to a 6.8 year old.

### 4. Define cut-offs

The definition of high and what scores are low, average, and high is somewhat arbitrary. You probably want to think about your application and what the consequences will be of these categorical designations.

That said, I think based on natural language, I think a reasonable starting point (using z-scores where mean is 0 and standard deviation is 1) would be:

* Low: z-score \< -1
* Average: -1 \< z-score \< 1
* High: z-score \> 1

I'd probably use language to also say that

* Very low: z-score \< -2
* Very high: z-score \> 2

Assuming a normal distribution, about a sixth of the distribution would be the low category, and another sixth would be in the high category. If the distribution is not normal (e.g., you have floor or ceiling effects), then you may prefer percentiles for the full distributions or raw scores, but in cases of published articles, you probably wont have that.

### Applying to the TIPI Example

Thus, for sake of illustration, here is how you would apply this to the above

For extraversion where the mean is 4.44 and SD is 1.45, then you might have cut-offs of low \< 2.99 \< average \< 5.89.

Anyway, as noted above, the publication present several different norms by gender and race. You may even have your own norms that is more relevant to your context.
> 2 votes

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Tags: measurement, personality, survey
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# Question
Title: Is there any difference in social status for gays and lesbians?
If we ignore religion, do gays and lesbians have different social statuses?

(Please add what biases you have in the question to support the answer, e.g. the grass is greener on the other side).

I did find this research report on mental health for LGB people but it does group everyone together (https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2853758/).

The report did say that social relation is an important part for mental health.

One of the other things that I found was that LGB or LGBT one group except one that was in favour for lesbian but based on a general study made in the USA that was on tolerance of LGB as a group so it's most a blur of gray. (http://www.pewresearch.org/fact-tank/2013/06/25/how-lgbt-adults-see-society-and-how-the-public-sees-them/)

I don't have a source for this: Even if it is more accepted to be lesbian, wouldn't I say that they do have a higher social status and I do feel like it is in general a very big difference on how accepted LGBs are and that really messes with it.

# Answer
> 1 votes
Well, I think one would have to make their own personal observation of this and do some research.

From what I've seen, being gay as opposed to lesbian, malexmale femalexfemale respectively, it's more acceptable to be gay. I believe this is because of how common "gay jokes" are, and how popular you see two men together in the media. In my hometown, when someone is introduced as gay, or "comes out of the closet" as they say, it's sort of funny and cute and nobody really cares. However, if it's a woman who announces her sexuality, then people are disgusted, shocked, confused, and she's more often than not labeled a "butch"

I come from a very religious place, but also a place where there's no public hate. There is general tolerance and some are liberal and very supportive of the LGBTQ+ community, but for the most part it is just a general cold tolerance.

I think this is in part due to how women have been viewed since the beginning of mankind. And also how women are represented in the media today. Usually it takes several years before a residue will be left of a certain message. Seeing two gay men has been so common that it's sort of settled into less open communities, and they will shrug at a man being gay. But because women haven't been portrayed as being lesbian for as long, and when they are they are perceived as "butch" (tomboy, tough, etc in other words) people are less accepting of them.

Women in my community are also seen as more "sacred" or "feminine" and the idea of tainting the typical girl who dresses appropriately, doesn't swear, upholds all religious doctrine 100%, and would never do anything wrong in her entire life is just absurd. It is normal for girls in my community who are not seen in this holy light to be labeled as "freaks."

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Tags: social-psychology, sexuality, sex-differences
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# Question
Title: Relation of confidence and problem solving ability
My personal experiences have shown me multiple times that by only boosting my confidence in my ability to solve a problem, without gaining any additional knowledge, I was able to solve it!

My question is, has this been studied that to what extent our confidence in our abilities can help us to find a solution for a problem?

If so, can you please provide a link?

# Answer
> 3 votes
Quick answer:

A brief Google search show cases where this occurred. For example, it seems that a study on medical students showed a significant relationship between confidence and ability after training, although not before training (Clanton et al., 2014). This being said, the Dunning-Kruger effect always comes to mind when such questions come up…

**References**

Clanton, J., Gardner, A., Cheung, M., Mellert, L., Evancho-Chapman, M., & George, R. L. (2014). The relationship between confidence and competence in the development of surgical skills. Journal of Surgical Education, 71(3), 405–412. http://doi.org/10.1016/j.jsurg.2013.08.009

# Answer
> 3 votes
I think what you are reffering to is known as self-efficacy.

> Perceived **self-efficacy** is defined as people's beliefs about their capabilities to produce designated levels of performance that exercise influence over events that affect their lives. Self-efficacy beliefs determine how people feel, think, motivate themselves and behave.
>
> ...
>
> A strong sense of efficacy enhances human accomplishment and personal well-being in many ways. People with high assurance in their capabilities approach difficult tasks as challenges to be mastered rather than as threats to be avoided. Such an efficacious outlook fosters intrinsic interest and deep engrossment in activities. They set themselves challenging goals and maintain strong commitment to them. They heighten and sustain their efforts in the face of failure.
>
> ...
>
> Most courses of action are initially organized in thought. People's beliefs in their efficacy shape the types of anticipatory scenarios they construct and rehearse. Those who have a high sense of efficacy, visualize success scenarios that provide positive guides and supports for performance. Those who doubt their efficacy, visualize failure scenarios and dwell on the many things that can go wrong. It is difficult to achieve much while fighting self-doubt.
>
> ...
>
> Perceived self-efficacy to control thought processes is a key factor in regulating thought produced stress and depression. It is not the sheer frequency of disturbing thoughts but the perceived inability to turn them off that is the major source of distress. Both perceived coping self-efficacy and thought control efficacy operate jointly to reduce anxiety and avoidant behavior.

Reference :

Bandura, A. (1994). Self-efficacy. In V. S. Ramachaudran (Ed.), Encyclopedia of human behavior (Vol. 4, pp. 71-81). New York: Academic Press. (Reprinted in H. Friedman \[Ed.\], Encyclopedia of mental health. San Diego: Academic Press, 1998).

# Answer
> 0 votes
There are studies that looked explicitly at confidence and performance. There is a well-known relationship between confidence and performance: the less skilled people are, the less calibrated their confidence is (they are less able to estimate whether they are correct or not), and the more overconfident they tend to be. It's sad, it means that the less knowledgeable people don't even realize they are not knowledgeable.

You can also draw conclusions indirectly from the psychosocial literature and for example the well established "stereotype threat" effect. Members of minority groups with a negative stereotype do not perform well when they are explicitly tested on that stereotype (e.g. African Americans on IQ tests, women on math tests, etc). But they perform as well as other groups if they are told the same test is testing something else; and they perform poorly on a tests that actually test something else if they are told it is about their stereotype. You can speculate that negative stereotypes decrease confidence and reduce performance.

There are also more studies you could draw on, for example showing that wrong feedbacks reduce learning rate etc. But at the top of my head, I can't think of a study that tested your precise question (if confidence boosts performance). My understanding of the confidence/decision-making literature is that the answer is no. What matters most is to have a well calibrated confidence (being confident when you are right, and not confident when you are wrong). Being underconfident (e.g. due to a stereotype), harms your performance, but being overconfident too.

Lichtenstein, S., & Fischhoff, B. (1977). Do those who know more also know more about how much they know?. Organizational behavior and human performance, 20(2), 159-183.

Steele, C. M., & Aronson, J. (1995). Stereotype threat and the intellectual test performance of African Americans. Journal of personality and social psychology, 69(5), 797.

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Tags: problem-solving, confidence
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# Question
Title: Is it possible to calculate the probability of a child having an IQ in a certain range based on their parents' IQ?
For instance, if two parents have IQs of 160, can one calculate the probability that their child has an IQ over 160?

# Answer
This is precisely the question Galton had in mind when he invented regressions. He tested it with heights. Given parents heights, their children height is actually more likely to be closer to the population mean. So high parents tend to have smaller children, and short parents taller children (hence the term "regression"). To answer your question, a children of parents with high IQs (160 is very high), is likely to have a higher IQ than the average population, but lower than the parents. This is even more true than for height as IQ is a lot less heritable. The precise likelihood can be calculated given some assumption.

Galton, F. (1886). Regression towards mediocrity in hereditary stature. The Journal of the Anthropological Institute of Great Britain and Ireland, 15, 246-263.
> 2 votes

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Tags: intelligence, statistics, genetics
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# Question
Title: What is the best time-effective study technique?
What is the most effective way to study? For instance, assume a student has the following 4 classes in parallel:

1- C++ & Data-structure
2- Logic Design
3- Linear Algebra
4- Integration

Should the student study 1 course per day, or study all 4 courses every day to study efficiently? In other words, should a student learn big chunks of information on one course/topic, or study multiple courses/topics in parallel to learn the most in the least amount of time?

# Answer
> 3 votes
According to the distributed learning strategy which is based on a phenomenon called spacing effect, it is better to study classes in parallel.

> **Distributed practice** (also known as spaced repetition or spaced practice) is a learning strategy, where practice is broken up into a number of short sessions – over a longer period of time. Humans and animals learn items in a list **more effectively** when they are studied in several sessions spread out over a long period of time, rather than studied repeatedly in a short period of time, a phenomenon called the spacing effect.
>
> **The opposite, massed practice**, consists of fewer, longer training sessions. It is generally a **less effective** method of learning.

Reference :

Greene, Robert L.. Spacing effects in memory: Evidence for a two process account. Journal of Experimental Psychology: Learning, Memory, and Cognition15. 3 (May 1989): 371-377

Challis, Bradford H.. (Mar 1993). Spacing effects on cued-memory tests depend on level of processing. Journal of Experimental Psychology: Learning, Memory, and Cognition 19. 2, 389-396.

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Tags: cognitive-psychology, learning, educational-psychology
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# Question
Title: What are the temporal limits of the auditory system?
I would like to know what the time scale is of the human ear. I mean, what is the shortest duration of a sound that a human ear can notice and what is the longest duration of a sound that a human ear can not track?

# Answer
> 7 votes
As far as I know, **auditory clicks** are the shortest possible auditory stimuli. The shortest auditory click I was able to find in the literature, and which was used in a psychophysical context (i.e., audible to a human) was 10 microseconds (Leshowitz, 1971).

The longest sound we can hear is pretty much defined as a human's maximum age I guess. While the auditory system definitely adapts to acoustic stimuli at the neurophysiological level (Pérez-González & Malmierca 2014), this neural adaptation does not become evident in gross psychophysical adaptations. In other words, prolonged acoustic stimulation does not lead to sounds becoming less audible, let alone inaudible. That, because tonal stimuli consist of continuously changing air pressure differences. Of course, a continuous pressure applied to the eardrum is not heard, but a stimulus like that is not sound, but simply pressure, as it has no tonal content.

<sub>**References**
**-** Leshowitz et al. J Acoust Soc Am 1971; 49, Suppl 2:462-6
**-** Pérez-González & Malmierca, *Front Integr Neurosci* (2014); **8**: 19</sub>

# Answer
> 6 votes
In terms of the shortest stimuli, the auditory system can process acoustic impulses, but defining the duration of an impulse is problematic. As the duration of the impulse gets shorter, the bandwidth gets broader. A 25 us impulse has frequencies between 0 and 20 kHz, as you decrease the duration of the impulse you add higher frequency components such that a 10 us impulse has a maximum frequency of 50 kHz. The upper edge of human hearing is 20 kHz so it is unlikely that we could detect a difference between a 25 us impulse and a 10 us impulse (or even a 1 us impulse), but assuming sufficient energy, all would be detectable. Making really short sounds with sufficient levels of energy is technically challenging and requires good transducers, but ultrasonic transducers exist.

The upper limit depends on what you consider the *human ear*. Durlach and Braida (1969) introduced the concepts of *sensory‐trace mode* and *context‐coding mode* to separate sensory limitations from memory limitations. The 15 papers in the series, written over 25 years, delve into the details (and then some), but basically after about 250 ms, listener switch from trace mode to context coding, suggesting this is the upper limit of processing by the *ear*.

That said, my recollection is that echolocating bats need precise temporal tuning (so sensory mode) over the time course of 10s of seconds. As humans are also able to echolocate, to an extent, there may be some aspects of the auditory system for which the neural trace degrades much more slowly.

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Tags: neuroscience, perception, neurophysiology, sensation, hearing
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# Question
Title: What's the technical name for this cognitive bias?
I'm pretty sure I've seen this cognitive bias described in the literature, but I can't find its official name, so I'll provisionally call it "the used-book finder's bias", based on the following vignette.

Say you are browsing through some used-book store, looking for nothing in particular, when you spot, tucked in some corner, almost hidden, a copy of some "classic" book. The book is in good shape, and the price is very attractive. What a find! You've got to have it, never mind the little voice reminding you that your reading list is already overcrowded, as are your bookshelves, and that you won't have time to read this book in the foreseeable future...

The cognitive bias I'm referring to is the intense compulsion to acquire the *serendipitous find*, even though one does not need it, and almost certainly will not do anything with it.

As someone who used to frequent used-book shops, I'm all too familiar with this cognitive bias. It led me to spend a lot of money, and acquire more books than I could even store, let alone read. (Eventually, I wised up.)

Mind you, the vast majority of the books I found this way were not really hard-to-find; I could easily get through other means (e.g. the library) *if* I ever really needed to read them. Moreover, if I had just paid full price for brand new copies of the very few among those books that I ultimately read, I would have still saved myself a lot of money.

The principal element of the bias, seems to me, is the strong feeling of *good fortune* one feels in such a situation. Conversely, one feels strongly that one would be a complete fool not to take advantage of such a lucky event.

# Answer
> 5 votes
I am not entirely sure about the proper scientific names but I think your issue revolves around buying things because they are

* cheap;
* hard to find.

The first is a notorious reason to buy stuff; the impulsive purchase of goods, simply because they are advertised as 'buy two, pay for one!'. This bargain hunting can indeed become pathological and **addictive** (source: Psychology Today).

The buying simply because a product is hard to find is a bit harder to frame in behaviors, but it is indeed a common phenomenon that people tend to buy stuff because they are exclusive (#55 here). Also, perhaps you simply wish to buy it just because you *can* (#26 here).

Further, buying stuff in general makes you feel good as it activates the reward circutry in our brain. As a consequence buying stuff can become an addiction (shopaholics).

There is actually a disorder named compulsive buying disorder. It was included in DSM-III, but not in later DSMs. It's not strictly defined but it has been associated with addictive disorders, obsessive-compulsive disorder, or mood disorders (Black, 2007).

<sub>**Reference**
**-** Black, World Psychiatry (2007); **6**(1): 14–18</sub>

# Answer
> 5 votes
Not sure what you describe is a cognitive bias in itself, but I suspect the scarcity heuristic may be part of the purchaser's rationalization. (See the wikipedia article for academic references.)

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Tags: terminology, bias, consumer-psychology, behavioral-economics
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# Question
Title: During body-scan ('sweeping') meditation, what does brain-imaging (e.g. fMRI) look like?
I do not know how extensive body scans have been studied with brain-imaging techniques, e.g. fMRI.

Body scan is a meditation technique developed by Jon Kabat-Zinn. It was derived from a meditation practice ('sweeping') of the Burmese U Ba Khin tradition.

> "It involves systematically sweeping through the body with the mind, bringing an affectionate, openhearted, interested attention to its various regions, customarily starting from the toes of the left foot and then moving through the entirety of the foot \[...\] From there, the focus moves into, successively, and slowly, the entirety of the pelvic region, including the buttocks and the genitals \[...\] and finally, to the face and head."
>
> "We are systematically and intentionally moving our attention through the body, attending to the various sensations in the different regions. That we can attend to these body sensations at all is quite remarkable. That we can do it at will, either impulsively or in a more disciplined systematic way, is even more so."
>
> "We might describe what we are doing during a body scan as tuning in or opening to those sensations, allowing ourselves to become aware of what is already unfolding."

I found it quite easy to practice and had interesting and unusual experiences (mostly pleasant).

My question is: Would any brain and brain-imaging expert - given this description - dare to guess roughly how a body scan may look like in a "brain scanner", e.g. recorded with fMRI?

I am not such an expert, nevertheless I dare to guess.

Presumably, a body scan will - mainly but not solely - take place in the areas of the cortical homunculus in the primary motor and sensory cortices.

I would guess that it is here that most of body scan related neural activity will occur. But in which manner: how will activity evolve and literally move around, how will it look like in the "brain scanner"?

Five possibilities come to my mind:

1. Experts and laymen will see nothing but a generally increased, enigmatically billowing activity of the cortical homunculus.
2. An expert would see some significant patterns, but only vague and hard to communicate.
3. Even the layman could see something:

* an overall increased activity of the cortical homunculus with somehow changing peaks of activity (highlights, representing the body region the attentional focus is currently on)
    * a mostly "dark" cortical homunculus with a wandering spotlight of activity
    * a mostly dark cortical homunculus with a fading-in/fading-out spotlight every now and then

Which of these possibilities do you - as a brain and/or brain-imaging expert - consider the most probable one? Other possibilities are welcome!

And of course hints to studies where this question has been experimentally attacked.

(I found one study but didn't delve deeper into it: there are too few images in it.)

# Answer
> 3 votes
The Mind of the Meditator may be what you are looking for: https://www.nature.com/scientificamerican/journal/v311/n5/full/scientificamerican1114-38.html

The image taken from the article gives some good explanation:

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Tags: cognitive-neuroscience, neuroimaging, meditation
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# Question
Title: Is Freudian Psychology a scientifically valid contribution to the Cognitive Sciences?
Freudian Psychology is based on the work of Sigmund Freud (1856-1939). He is the founder of Psychoanalysis and is credited with establishing the field of verbal psychotherapy. Freud is known for his theories of the unconscious mind, dreams, infantile sexuality, libido, repression, and transference, ego, and the superego.

However, despite his acclaimed influence on psychology and psychotherapy, it seems that Freudian Psychology is criticized by many (Horgan, 2017) and is even considered to be pseudoscience.

Is Freudian Psychology considered to be a scientifically valid approach?

Sigmund Freud. source: Wikipedia

Related:
What are the different branches of Psychoanalysis?
Is there anything in Freudian psychoanalytic theory that is scientifically sound?
Which schools of psychotherapy are most credible to a hard scientist?

# Answer
> 15 votes
**Short answer**
Freudian Psychology is considered by many to be pseudoscience, but as pointed out in another answer, there have recently been increasing numbers of comparisons between psychoanalysis and other depth psychology schools (e.g. a long-term study of CBT vs psychoanalysis for depression, where CBT is not much effective) with results which show that

* psychoanalysis is just as effective as CBT for many disorders,
* it is more effective for certain disorders, and
* it is less effective for others.

In other words, psychoanalysis and CBT are both appropriate for certain patients and disorders and that the decision between them has to be made case by case.

**Background**
Freudian psychology is still applied, and Freudian psychoanalysis is still actively used today and according to the Science Council, **Science** is...

> ...the pursuit and application of knowledge and understanding of the natural and social world following a systematic methodology based on **evidence**.

**It is in the scientific evidence where the support of the Freudian approach is limited**. However, Freud's ideas have never been extensively assessed scientifically. For instance, there is no unambiguous evidence that psychoanalysis works (Horgan, 1996) and supporters of Freud’s theories are believed to be influenced mainly on the confirming evidence, while they largely ignore the disconfirming cases (Shermer, 2011). Indeed, Sulloway (Dufresne, 2007) argues that...

> The greatest failing of psychoanalysis is its blatant rejection of the scientific method. Without such methods for critical thinking, a discipline inevitably drifts from one pseudoscientific system of belief to another.

It should be stressed, however, that the human psyche is extremely complex and largely not understood. Other theories that are generally regarded as valid science, such as the string theory in astrophysics have never been proven either, and the relativity theory of Einstein took about hundred years to be proven right.

Indeed, distinguishing between science and pseudoscience is problematic (Shermer, 2011). As covered in this answer to Does suppressing a desire make it more powerful?, Freud's work is derived from empirical evidence and backed up with high profile journal articles. Nonetheless, in the gray area between science and pseudoscience, according to eminent critics such as Karl Popper, Frank Cioffi, and Adolf Grünbaum, the theories of Freud are generally placed in the area of pseudoscience as they are seen as non-falisifiable.

Many authors assume that to be pseudoscientific, an activity or a teaching has to satisfy the following two criteria (Hansson 1996):

* it is not scientific, and
* its major proponents try to create the impression that it is scientific." (Hansson, 2008)

With regard to Hansson's first point, a PsychologyToday article (2016) points out that

> psychology was defined by the application of scientific method(s) and psychologists conduct valuable research and have developed some key insights into animal behavior, cognition, consciousness, and the human condition.

Hansson, has since updated his definition of pseudoscience to an "improved version" (Hansson, 2013)

**References**

**Supporting network posts**

**Note**
The community is invited to improve this answer. This question-and-answer is discussed here in meta.

# Answer
> 8 votes
Some thoughts:

1. You have to differentiate between psychoanalysis (PA) as a method and procedure for psythotherapy and PA as a theory of the human psyche. Criticism is mostly aimed at PA as a theory.
2. The only therapeutic school that has been extensively evaluated is Cognitive Behavioral Therapy (CBT). In these evaluations, CBT is shown to "work". The absence of positive proof for PA (and other schools, such as systemic, gestalt, or humanist psychotherapy) is often interpreted by critics of PA to imply that only CBT is a valid method for psychotherapy and that PA does not "work". Recently, there have been increasing numbers of comparisons between CBT and other cognitive-behavioral schools and PA and other depth psychology schools (e.g. a long-term study of CBT vs PA for depression, where CBT is not much effective). The results show that PA is just as effective as CBT for many disorders, that it is more effective for certain disorders, and that it is less effective for others. Or in other words, that PA and CBT are both appropriate for certain patients and disorders and that the decision between them has to be made by case. One remaining disadvantage of PA, though, is that it is more time- and cost-intensive: PA therapies take years at three to four sessions per week, while CBT takes months at one session per week or less. Where they are equally effective, CBT is to be preferred, therefore.
3. Certain PA therapeutic concepts such as transference and countertransference have been absorbed by non-depth-psychology therapies, because their therapeutic concepts has been lacking in this aspect. That is, PA survives in certain concepts that have become common therapeutic lore.
4. The most intense criticism is aimed by experimental psychologists at PA as a theory of the psyche. "Scientific" psychologists believe (sic) that the Oedipus Complex is pseudoscientific nonsense. But there has been some experimental research into PA concepts, e.g. the defense mechanisms. Roy Baumeister has reviewed experimental evidence for a number of these mechanisms and has found experimental evidence for the existence of some of them. Plainly said: Freud was right in at least some of these mechanisms. Another concept that is generally accepted to be accurate is the unconsious. Few non-PA psychologists today would dare to claim that the unconscious does not exist.
5. PA has survived as a therapy because of institutional power (they have been a part of the health system in Western countries for a hundred years and are difficult to displace) and because it was an extremely popular ancillary science in cultural theory (e.g. to analyze literature, cf. Lacan and poststructuralism).

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Tags: psychoanalysis, freud, pseudoscience
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# Question
Title: What is the difference between implicit and explicit attitudes?
Although it is clear that implicit and explicit attitudes are not same, how do they differ is not. I believe establishing the relation between them would surely help deducting it's meaning in context of psychology. It seems that research by Nosek (2007) would be relevant.

Nosek, B. A. (2007). Implicit–explicit relations. Current Directions in Psychological Science, 16(2), 65-69.

# Answer
Although implicit and explicit attitudes are not the "same" they frequently overlap (e.g. people that are explicitly racist are usually implicitly racist). Both are a positive or negative feeling towards an object. The primary difference between the two is found in conscious awareness of a particular attitude and how the attitude is expressed. Implicit attitudes are unconscious while explicit attitudes are conscious. Explicit attitudes are tempered by things like social desirability. Work with implicit attitudes tests like the IAT have shown implicit biases against things like race, age and sex. Most people do not explicitly subscribe to these biases but still unconsciously harbor latent preferences.

Check out Project Implicit to take a variety of IAT's and learn more: https://implicit.harvard.edu/implicit/
> 5 votes

# Answer
An attitude can actually exist at two different levels. Explicit attitudes are attitudes that are at the conscious level, are deliberately formed and are easy to self-report. On the other hand, implicit attitudes are attitudes that are at the unconscious level, are involuntarily formed and are typically unknown to us.
> 1 votes

# Answer
Explicit attitudes are consciously accessible attitudes that are controllable and easy to report. Implicit attitudes are uncontrollable and perhaps not consciously accessible to us.
> 0 votes

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Tags: cognitive-psychology, social-psychology
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# Question
Title: Is remembering a list of words an example of semantic or episodic memory?
I'm having a hard time making a clear distinction between semantic and episodic memory. When presented with idealized examples, I find the breakdown clear; describing a trip to Paris is an example of episodic memory, describing the structure of a cell is an example of semantic memory.

However, when it comes to experimental settings, things suddenly start to look more murky. For example, say that one is presented 20 words in a sequential fashion and then is asked to repeat as many of these as possible. Are we dealing with episodic memory then? Does it make any difference if one is forced to recollect them in the same order as they appeared? Many researchers seem to consider this situation an example of episodic memory (just as an example, see van der Helm et al., 2011), and indeed, the man who invented the concept of episodic memory also did so at the time of its conception (Tulving, 1972; p.390).

However, later, Tulving has revised his original definition. In a more recent article (Tulving, 2002) he writes:

> I had been wrong in 1972 when I had assumed that the traditional, Ebbinghaus-inspired, study/test laboratory experiments of verbal learning and memory had dealt with episodic memory. They had not. Two important features of episodic memory were missing.
>
> One had to do with the contents of what the subjects in the experiments had to learn. Episodic memory is about happenings in particular places at particular times, or about “what,” “where,” and “when” \[...\] Traditional laboratory experiments, however, were almost invariably concerned with “what.” Subjects are asked, “What do you remember of the presented material?” They report their knowledge in tests such as free recall, cued recall, or recognition. Subjects’ memory for “where” and “when” was hardly ever examined.
>
> The other missing feature was what I referred to in Elements as “recollective experience,” or conscious awareness of what had happened in the past. In traditional experiments the experimenter assumes that the overt behavioral response reflects the subject’s mental state; that is, that behavior is a faithful index of cognition. The reasoning goes something like this: Surely, if the subject recognizes an item in a recognition test, it means that he remembers it from the list, that is, that he has a conscious recollection of the item’s occurrence in the study list. How could it possibly be otherwise?
>
> As subsequent history showed, it could be otherwise. Research on implicit memory \[...\], or so-called nonconscious memory \[...\], has overwhelmingly proved that one and the same behavioral response in a study/test experiment could represent conscious awareness of the retrieved item’s experimental history as readily as it could represent total lack of such awareness.

So which one is it? Are there any large disagreements within the community of what episodic memory actually is? Are word list tests seen as something that at least captures a small part of episodic memory? If remembering a list of words isn't an example of episodic memory, then what is it an example of?

# References:

* van der Helm, E.; Gujar, N.; Nishida, M; Walker, M.P. (2011).Sleep-Dependent Facilitation of Episodic Memory Details. PLoS ONE, 6(11).
* Tulving, E. (1972). Episodic and semantic memory. In E. Tulving and W. Donaldson (Eds.), Organization of Memory (pp. 381-402). New York: Academic Press.
* Tulving, E. (2002). Episodic memory: From mind to brain. Annual Review of Psychology, 53, 1-25.

# Answer
> 5 votes
The definitive categorization of memory is an example of semantics *(an irony I enjoy in answering this question).*

Firstly, you have asked four questions in one.

> * So which one is it?

Definition of *semantic:*

> adjective
> relating to meaning in language or logic.

Semantic is the imposed meaning that human beings give things.

Remembering a list of words, would be semantic memory, as the person is required to recollect a list, that has been arbitrarily compiled, as opposed to recalling the experience of reading the words.

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> * Are there any large disagreements within the community of what episodic memory actually is?

Not that I am aware of, but I am not an expert and have not investigated this thoroughly.

---

> * Are word list tests seen as something that at least captures a small part of episodic memory?

Word list test would be capturing semantic memory, though I doubt they would form long term memory, as they are only being held for a short period of time, have no emotional context, nor form the part of pattern or logic of any semantic learning. Taking and remembering the test itself would form episodic memory, in recalling the event, time and place, with, the long term semantic memory in knowing how to do such a test. I have addressed this in more detail under the next point.

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> * If remembering a list of words isn't an example of episodic memory, then what is it an example of?

To answer this, I am going to present two alternative arguments.

**As episodic memory.**

To regard it as episodic memory, (but short term memory, which is muddying the waters, as the information only needs to be keep in the memory for a short term and would be used within the working memory) so in terms of it being episodic, it is unlikely to be recalled effectively at a later date (for most people). I would liken it to being shown images of animals, with no purpose of pattern, except the person is asked to retain a memory of what they have seen. Like going to a museum and then being asked, what did you see there, as opposed to going to a museum and then being asked what was the history of the steam engine, which would be recalled from semantic memory of reading about the team engine at the museum.

In this context, a test of semantic memory would be to give the individual the rules of a new game and ask them to memorise them. If a person was being asked to remember the *periodic table of elements*, this would be semantic memory, as it would be something the person would later use as a useful pool of human defined information, like the rules of a card game.

**As Semantic memory**

So in terms of the concept of semantic memory being the recall of facts, as opposed to episodic memory being the recall of personal facts, it could be argued that recalling a list is using semantic memory. The list is a generic and semantic thing (human created rules, as opposed to the spontaneous and authenticity of life experience, that creates episodic memory). So regardless of the intention, it is a semantic list, that has no bearing on *action* or what is occurring, hence the episodic memory. The episodic memory, may be of perspiring whilst trying to recall 20 unrelated words. So the person is trying to jam 20 words into their short term memory, in a *rote learning* fashion. Rote memory would be regarded as semantic memory.

> Rote Memory (item or semantic memory) (1)

Episodic memory could be considered explicit memory, whereas semantic memory could be considered implicit memory, as it does not require the recall of a particular event, but it the memory of a generic mental exercise, as opposed to the test itself.

The ability to use a pen and write out the test form, is an example of implicit procedural memory, the memory of a teacher leaning over you and showing you how to write is an example of explicit, declarative, episodic memory. Knowing how the testing process works is an example of implicit, declarative, semantic memory.

---

Semantic and episodic memory are related, both being types of declarative memory.

> **Types of Memory**
>
> **Declarative vs. Procedural Memory**
>
> Declarative memory is recall of factual information such as dates, words, faces, events, and concepts. Remembering the capital of France, the rules for playing football, and what happened in the last game of the World Series involves declarative memory. Declarative memory is usually considered to be explicit because it involves conscious, intentional remembering.
>
> **Semantic vs. Episodic Memory**
>
> Declarative memory is of two types: semantic and episodic. **Semantic memory** is recall of general facts, while **episodic memory** is recall of personal facts. Remembering the capital of France and the rules for playing football uses semantic memory. Remembering what happened in the last game of the World Series uses episodic

---

> **Episodic memory** is the memory of autobiographical events (times, places, associated emotions, and other contextual knowledge) that can be explicitly stated. It is the collection of past personal experiences that occurred at a particular time and place. For example, if you remember the party on your 6th birthday, this is an episodic memory. They allow you to figuratively travel back in time to remember the event that took place at that particular time and place.
>
> Tulving has seminally defined three key properties of episodic memory recollection. These are: a subjective sense of time (or mental time travel), connection to the self, and autonoetic consciousness. Autonoetic consciousness refers to a special kind of consciousness that accompanies the act of remembering which enables an individual to be aware of the self in a subjective time. Aside from Tulving, others named the important aspects of recollection which includes visual imagery, narrative structure, retrieval of semantic information and the feelings of familiarity.

---

> **Semantic memory** refers to the memory of meanings, understandings, and other concept-based knowledge, and underlies the conscious recollection of factual information and general knowledge about the world. Semantic and episodic memory together make up the category of declarative memory, which is one of the two major divisions in memory. With the use of our semantic memory we can give meaning to otherwise meaningless words and sentences. We can learn about new concepts by applying our knowledge learned from things in the past. The counterpart to declarative, or explicit memory, is procedural memory, or implicit memory.
>
> Semantic memory includes generalized knowledge that does not involve memory of a specific event. For instance, semantic memory is knowing how to add and subtract, whereas episodic memory is the specific memory of being taught how to subtract.

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*Disclaimer: I could be completely wrong.*

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Reference:
(1) BRAIN Research Compatible Memory Strategies Judy Willis, M.D., M.Ed.

# Answer
> 2 votes
The answer is episodic. Episodic memory is responsible for storing information about events (or episodes) we have experienced; whereas semantic is for storing information about the world, such as the meaning of words. While semantic memory would be required to understand and thus encode the words in the first place, remembering the list of words would require episodic memory. Hope this helps.

# Answer
> 1 votes
I agree there is some murkiness, as learning a list of words doesn't seem to resemble what we normally think of as an 'event'. I think the answer is episodic when there is a single learning episode, and the memory test asks something like "what were the words you learnt in this list in this experiment" (even if the qualification "in this experiment") is sometimes only implied. In that case the memory is likely to be contextual and episodic. Think about the simpler example of learning individual words - these are known words, but if the task successfully taps memory for the episode in the current experiment, it is typically regarded as an episodic task, and people report recollective experience surrounding individual items (e.g Tulving's original remember-know paper here as pdf http://www.esalq.usp.br/lepse/imgs/conteudo\_thumb/Memory-and-Consciousness.pdf)

But if there are multiple learning episodes a semantic memory may emerge gradually - and according to some recent work on schemas, if the list corresponds well to prior knowledge there may be a 'fast track' to semantic memory, and hippocampal independence (e.g. Tse, Morris and others, http://science.sciencemag.org/content/316/5821/76.full), but there are other views.

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Tags: memory, long-term-memory, episodic-memory, semantic-memory
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title: Sleep vs. Trance

text:
# Question
Title: Sleep vs. Trance
I've been recently reading about hypnosis and I'm asking this question because I've had certain personal experiences that makes me confuse the term Trance with just simple sleep.

I'm not a fan of Heavy Metal music, but I sometimes listen to it because it somehow calms me down and I usually listen to music while wearing my big uncomfortable headphone, sitting in my chair which is also very uncomfortable and having my legs resting on my desk. When I listen to music, I almost always start to imagine things, for example I sometimes try to imagine a trip to a certain place, or I try to make up a music video for that tune in my mind. The reason why I mentioned Heavy Metal is that, when I listen to that kind of music in that uncomfortable position, I fell asleep in a way that I can still hear the music and this goes on until the whole album is finished and when I wake up I feel really really fresh like my brain has been fully reset. However, this feeling does not happen when I just go to bed or I just get some rest.

What I have read about hypnosis suggests a similar condition, which is when someone is between being conscious and unconscious (or I can't describe it well). However, the videos I have seen about it emphasis on comfort. Would this be (what's I'm experiencing) a kind of trance or hypnosis, or it is just a normal nap?

And would there be any reason why a music full of violence, yelling, and rough sounds would calm down the brain and put it into a semi-conscious state and then makes it very refreshed afterwards?

# Answer
Wearing those big headphone is indirectly a way to isolate yourself from the surrounding sound. That is usually a prelude for relaxation, or meditation. *(In people with audiotory disorder, or with authism, this is a way they can feel good as that remove a big source of stimulis)*

On the other side for the heavy metal, study have found it can be a stress reliever, as stated in that study;

Extreme Metal Music and Anger Processing

> The findings indicate that extreme music did not make angry participants angrier; rather, it appeared to match their physiological arousal and result in an increase in positive emotions. **Listening to extreme music may represent a healthy way of processing anger for these listeners**.

Other news site suggest the same;

> One student said: "It helps me with stress. It's the general thrashiness of it. You can't really jump your anger into the floor and listen to your music at the same time with other types of music."

It's not a fact, but some smaller study clasify heavy metal fan at the same level than classical fan;

> Classical music and heavy metal fans might not be different after all. New research by scientists at Heriot-Watt University has found that not only are peoples' personalities linked to their taste in music – classical and heavy metal listeners often have very similar dispositions.

With thoses study in head, I have no difficulty to understand why you can relax to such music. Is it hypnosis, trance or such ? who know, but something is sure is that those headphone and heavy metal is a good mix to deeply relax / meditate.
> 5 votes

# Answer
It's highly plausible (judging from your description) that you induce some sort of hypnotized state. I highly doubt it's strongly related to heavy metal though. The state of mind you're hinting at is not really a state between the subconscious and conscious. It's your mind deceiving your body that you're asleep without losing awareness. The increased visual imagination indicates to me that you're approaching a dreamlike state.

What about your dreams? I suggest u start writing a dream journal. Also, try practicing meditation before you go to bed and see if you achieve similar results.
> 2 votes

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Tags: sleep, music, hypnosis
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title: How can visual thinking be avoided?

text:
# Question
Title: How can visual thinking be avoided?
I have seen a lot of resources online about how to teach people visual thinking, but I've seen a lot less on the opposite: how to avoid visual thinking. The problem with visual thinking is that it is inherently concrete, while words are inherently abstract. Given that some subjects are more abstract than others, it is preferable in those subjects to not use visual reasoning.

How can visual thinking be avoided?

# Answer
**Short answer**
In normally sighted people visual thinking is the dominant mode of thinking and may be intimately associated even with verbal thinking and hence difficult to root out completely.

**Background**
Human thought can be generally divided into **visual** and **verbal thinking**. Visual thinking is mediated by **visual imagery**, where imagery visual representations are created of things that have been, are, or will be (*e.g.*, life events such as memories of a recent vacation). In contrast, verbal thinking involves thinking in words, for example when you are thinking about what and how you will tell something to friends or colleagues, *i.e.*, **inner speech** (source: Harvard Gazette, May 2017).

A study by Amit *et al* (2017) investigated subjects' brain activity when recalling images or sentences. Verbal thoughts resulted in more robust activation of language centers in the brain than during visualizations. However, subjects generated visual images regardless of whether their intent was to visualize or to think verbally. One possible interpretation the authors provide is that visual thinking is a primary mode of thought, which is supported by the notion that verbal abilities appeared later in human evolution and also appears later in childhood.

An interesting notion here is of **congenitally blind people** that lack visual memory altogether. In these instances, visual imagery is totally absent and in these people verbal thinking may be the only mode of thought available (Zimler & Keenan, 1983). In congenitally deaf-blind individuals the mode of thinking may be further warped into tactile thoughts. These considerations may lead to believe that with sufficient practice, pure-verbal thinking may at least theoretically be possible in the sighted.

<sub>**References**
**-** Amit *et al*., *Neuroimage* (2017); **15**(152): 619-27
**-** Zimler & Keenan, *J Exp Psychol Learn Mem Cogn* (1983); **9**(2): 269-82</sub>
> 1 votes

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Tags: cognitive-psychology, visualization, thought, self-discipline
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title: How can I test reaction time?

text:
# Question
Title: How can I test reaction time?
How can I measure someone's ability for the speed to which they react to something? Is their a way to test something like a person's reaction timing that doesn't involve something as simple as the ruler test, but rather something a bit more complex.

Edited: The ruler test: https://www.youtube.com/watch?v=yn6WRm6TiPk I have not yet done initial research on this topic because I want some good opinions on sources that I can use to better my understanding of this topic. I apologize if I was not clear at first.

# Answer
It is very typical to record response times. Usually using a computer keyboard. It's easy to program or some software can do it for you (e.g. e-prime). You can also use already-made response boxes (e.g. RTbox), or make your own (e.g. with an arduino). As pointed out, it is usually good to control for performance to prevent speed-accuracy tradeoff confounds.

Li, X., Liang, Z., Kleiner, M., & Lu, Z. L. (2010). RTbox: a device for highly accurate response time measurements. Behavior Research Methods, 42(1), 212-225.

Schubert, T. W., D’Ausilio, A., & Canto, R. (2013). Using Arduino microcontroller boards to measure response latencies. Behavior research methods, 45(4), 1332-1346.
> 4 votes

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Tags: developmental-psychology
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# Question
Title: What is the cause of frequent nightmares?
Is there a reason why people dream of demons, ghosts, and other scary creatures? More specifically:

**What factors cause frequent nightmares to occur**?

# Answer
Nightmares can be defined as (Pagel, 2000):

> ...vivid and terrifying nocturnal episodes in which the dreamer is abruptly awakened from sleep. Typically, the dreamer wakes from REM sleep and is able to describe a detailed, associative, often bizarre dream plot. Usually, the dreamer has difficulty returning to sleep.

Nightmares are common and can be a normal reaction to stress. Frequent occurrence of nightmares, however, may become a disorder when it impairs the sufferer's everyday life and may then be referred to as Nightmare Disorder (formerly Dream Anxiety Disorder) or "repeated nightmares," which is a term defined more specifically as a series of nightmares with a recurring theme (source: Psychology Today).

**Nightmare disorder** is defined in the Diagnostic and Statistical Manual of Mental Disorders (DSM-5) as:

> \[R\]epeated awakenings with recollection of terrifying dreams, usually involving threats to survival, safety or physical integrity.

Causes of nightmare disorder, according to WebMD, Psychology Today and (Sheaves *et al*., 2015) are:

* Anxiety or stress, for example due to a major life event
* Depression
* Psychosis
* Sleep deprivation
* Illness with a fever
* Medication side effects
* Drug or alcohol withdrawal
* Excessive alcohol consumption
* Sleep apnea, narcolepsy or restless legs syndrome or other sleep disorders
* Eating just before going to bed, which raises the body's metabolism and brain activity

<sub>**References**
**-** Pagel, *Am Fam Physician* (2000); **61**(7): 2037-42
**-** Sheaves *et al*., *Can J Psychiatry* (2015); **60**(8): 354–61</sub>
> 7 votes

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Tags: sleep, dreams
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# Question
Title: Efficiency of multitasking depending on task difficulty
How does the efficiency of multi-tasking differ by task type? My understanding is that multitasking impairs efficiency for cognitively challenging tasks.

Does this apply to trivial tasks as well?

# Answer
First, it is important to disambiguate between *concurrent multitasking* and *sequential multitasking* (Salvucci et al, 2009). In a recent publication I present a short overview on related work of both (Jeuris and Bardram, 2016):

> During concurrent multitasking cognitive resources have to be divided across several competing parallel tasks, such as driving while talking on the phone. Many ‘dual-task’ studies investigate dual-task interference and reduction of performance while performing two simultaneous tasks. ...
>
> In contrast to concurrent multitasking, sequential multitasking denotes the interleaving of several primary tasks which are executed one at a time. ... Studies investigating sequential multitasking are among other things interested in measuring the effects of task interleaving on productivity and accuracy. ...
>
> Results show an inverted U-relationship between multitasking and productivity; there is thus an optimal amount of task switching which leads to the highest productivity. However, increased levels of multitasking lead to a significant loss in accuracy, indicating a trade-off between productivity and accuracy (Adler & Benbunan-Fich, 2012).

In regards to the effect of *task difficulty* on sequential multitasking, "subjective task difficulty has been found to be a determining factor: easy tasks benefit from multitasking by increasing stimulation, whereas hard tasks decrease performance as the result of an overload in mental workload (Adler & Benbunan-Fich, 2015)".

So to answer your question, at least one study has found that for the tasks they used more challenging tasks do 'suffer' more from multitasking. However, there is still an optimum amount of multitasking.

<sub> Salvucci, D. D., Taatgen, N. A., & Borst, J. P. (2009, April). Toward a unified theory of the multitasking continuum: From concurrent performance to task switching, interruption, and resumption. In Proceedings of the SIGCHI conference on human factors in computing systems (pp. 1819-1828). ACM.
Jeuris, S., & Bardram, J. E. (2016). Dedicated workspaces: Faster resumption times and reduced cognitive load in sequential multitasking. Computers in Human Behavior, 62, 404-414.
Adler, R. F., & Benbunan-Fich, R. (2015). The effects of task difficulty and multitasking on performance. Interacting with Computers, 27(4), 430-439.
Adler, R. F., & Benbunan-Fich, R. (2012). Juggling on a high wire: Multitasking effects on performance. International Journal of Human-Computer Studies, 70(2), 156-168. </sub>
> 5 votes

# Answer
The effects of multitasking are apparent even for the most trivial tasks. For example try walking and eating a sandwich at the same time, you will walk slower and more irregular. The multitasking effects though, are much less when the competing tasks are simple or familiar.

Exctract from this article :

> In experiments published in 2001, Joshua Rubinstein, PhD, Jeffrey Evans, PhD, and David Meyer, PhD, conducted four experiments in which young adults switched between different tasks, such as solving math problems or classifying geometric objects. For all tasks, the participants lost time when they had to switch from one task to another. **As tasks got more complex, participants lost more time**. As a result, people took significantly longer to switch between more complex tasks. Time costs were also greater when the participants switched to tasks that were relatively unfamiliar. They got up to speed faster when they switched to tasks they knew better.

Reference:

Rubinstein, J. S., Meyer, D. E. & Evans, J. E. (2001). Executive Control of Cognitive Processes in Task Switching. Journal of Experimental Psychology: Human Perception and Performance, 27, 763-797.
> 1 votes

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Tags: cognitive-neuroscience, performance, cognition, neuropsychology
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# Question
Title: What are the definitions of 'multi-channel coding' and 'opponent channel coding'?
I am looking for the definitions of

* Multi-channel coding
* Opponent-channel coding

And specifically in the context of visual adaptation. I have searched for information on the web and in books, but I am unable to find accurate definitions.

# Answer
> 1 votes
**Short answer**

* Multi-channel coding in color vision refers to the different photoreceptors in the retina.
* Opponent-channel coding refers to the opposing color pairs: the red-green and yellow-blue axes.

**Background**

I think you are referring to terminologies often used in color vision.

* **Multi-channel coding** generally refers to different types of photoreceptors in the retina, namely **rods and cones**. In terms of color vision, it is the cones doing the work. In trichromatic species, such as humans, there are three types of cones in normally sighted people, namely red, green and blue cones. So humans have a 3-channel color system, the same as your computer screen you are looking at now, namely R, G, and B channels.
* **Opponent-channel coding** refers to the opponent theory of color vision as proposed originally by Hering. It basically states that our RGB color system defines color space by 3 opponent processes, namely a black-white, a red-green and a blue-yellow opponent system (Fig. 1). Basically it is theorized that red opposes green, yellow opposes blue and white opposes black (and *vice versa*). This means that colors are mixed between these channels (*e.g.* a reddish blue equals purple), but that colors within channels are mutually exclusive (*e.g.* there exists no such thing as a yellowish blue).

Fig. 1. Hering model of color vivion. source: University of Calgary

**Reference**
**-** Gouras, Color Vision. In: Kolb *et al* (eds), *Webvision. The Organization of the Retina and Visual System*. Utah University

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Tags: neuroscience, perception, vision, neurophysiology, sensory-perception
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# Question
Title: For binary (spike train) signals, take FFT of signal or autocorrelation of signal?
I want to characterize a binary time-series signal *x* (derived from neuron action potential data) in the frequency domain.

Should I use the FFT of the original signal *x*, or the power spectrum (FFT of the autocorrelation of *x*, which is defined as $k(n)=E\[x(t)\cdot x(t-n)\]$ )?

Also, does anyone know any literature which explicitly talks about this, or at least took sides?

# Answer
> 2 votes
For binary data (spike-trains), people use a spike-train autocovariance function (same as autocorrelation but subtracting the mean firing rate). It's commonly used to study brain oscillations (e.g. Engel & Konig, 1991). There is a good description of the math in the Dayan & Abbott (page 27).

Dayan, P., & Abbott, L. F. (2001). Theoretical neuroscience (Vol. 806). Cambridge, MA: MIT Press. Engel, A. K., & Konig, P. (1991). Interhemispheric synchronization of oscillatory neuronal responses in cat visual cortex. Science, 252(5009), 1177.

# Answer
> 1 votes
As this answer explains, the Fourier transform of the autocorrelation of $x$ is the same as the magnitude squared of the Fourier transform of $x$. The autocorrelation of x can be expressed as $x(t)\*x(-t)$, where * means convolution and the Fourier transform of the autocorrelation is then $X(w)X^\*(w)=|X(w)^2|$, which of course is the Fourier transform of the original signal $x(t)$.

As for references, see this answer.

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Tags: theoretical-neuroscience, computational-modeling
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# Question
Title: Cognitive bias of comparing numbers on a relative scale
Is there a name for the bias of comparing numbers on a relative scale?

Here are a few examples.

The car salesman sells you a \\$900 navigation system as an up-sell to a \\$30,000 car. It doesn't seem like that much because it 900 is a relatively small percentage of 30000. And let's say a top quality system installed, away from the dealership is \\$700; a difference of \\$200.

What causes us to think \\$200 isn't that much?

But if shopping in a store where the top priced GPS was \\$700 and all the others are priced around \\$500, now \\$200 seems too much.

Or how about a homeowner trying to sell a house for \\$200,000 when a potential buyer bids at \\$185,000 because of water damage in one room. The seller accepts even though the cost to repair the damage might be only \\$10000. The \\$5000 doesn't seem like that big of a loss for the hassle of having to do the repair, but in a lot of other circumstances (like selling a car) it's a deal breaker.

Another. Take a trip to a neighboring town and you might go a mile or two out of your way to see an attraction you just discovered. Take a trip across the country and you might visit a whole other state, hundreds of miles out of your way.

I know that anchoring bias can cause you to, for instance, perceive a price as being lower because of false higher price. But is it the same as this relative scaling bias? Or is this called something else altogether?

# Answer
> 4 votes
It's been called “relative thinking” in a few places (eg http://journal.sjdm.org/11/10921/jdm10921.html). The earliest I can find is in a 2004 article by Ofer Azar. A Google Scholar search turns up many other references to the term as well.

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Tags: cognitive-psychology, bias
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# Question
Title: How to measure galvanic skin response with wearables?
I'm trying to measure galvanic skin response in real-time with a wrist-wearable device, similar to what is being done in the paper "Using Noninvasive Wearable Computers to Recognize Human Emotions from Physiological Signals" which is used the, now discontinued, BodyMedia SenseWear. What solutions exist for this problem? From my preliminary research, I have found:

Are there other solutions that I've missed? How does one compare the accuracy of these various solutions?

# Answer
iMotions has a pocket guide on GSR targeting a layman audience (believe the PDF you can request might be more up-to-date). One key thing to point out is (emphasis added):

> Our body has about three million sweat glands. The density of sweat glands varies markedly across the body, being highest on the forehead and cheeks, the **palms and fingers** as well as on the sole of the feet.

For wrist-worn devices this means ideally you place the electrodes on the **palms or fingers**. Measurements on the wrist are much less sensitive, as shown in Seanny123's answer in case of the Empatica E4. Of course, not all experiments allow to place electrodes there, in which case electrodes on the wrist might still be worthwhile exploring.

Wearable devices supporting electrodes on the palms/fingers:

Watch-like devices, with electrodes placed on the wrist:

Other wearables:

<sub> Disclosure: I work for iMotions. Feel free to edit this list and include any other wearable devices you know of. </sub>
> 4 votes

# Answer
A system that I am currently testing is the MoviSens EdaMove. The system consists of a small device that can be attached to the arm, and two electrodes to measures EDA at the palms of your hand. The EdaMove uses the exosomatic method, by applying a 0.5V direct current, and samples with 32 Hz. An accelerometer is also included in the sensor, so that you can correct the EDA recordings for movement.

So far, the recordings are pretty good, but I haven't done any formal testing yet. Usability-wise, it may not be the best solution, since it is somewhat more intrusive than a wristband/watch.

**Update:** This is the fun part. Skin conductance is a measure of skin sweatiness. Unfortunately, the stickers that attach the sensors to the skin (similar to how ECG/EEG-reference sensors are attached) let loose when the hands start to sweat. This is even more so with many movements. For tasks that require much manual work or fine hand-movements, the EdaMove may not be the best sensor.

---

From the E4, I know that performance is not perfect, but it is okay. Benefit is that the E4 also includes an PPG sensor and accelerometer. Moreover, the E4 allows you to monitor the recordings in real time with their Android/iPhone app.

There are two major issues though with the E4. 1: It needs a good connection with the skin. If not, you could rather easily have missing data (especially so for the HRV sensor). The sensor should thus fit rather tightly. 2: Empatica applies some filtering of the data before you can extract it. It is not clear, however, to what extent it is being filtered. *NB. The website states that raw-data is provided. Only the interbeat intervals (IBI), an HRV metric appears to be filtered.*
> 4 votes

# Answer
## Accuracy Comparisons

In Simon Ollander's thesis "Wearable Sensor Data Fusion for Human Stress Estimation" the Empatica E4 sensor is compared with laboratory quality equipment. Specifically, in the case of GSR, these were finger-tip electrodes as shown below:

Two tasks were compared, D2 and SCEPT. The SCEPT task consisted of the subject putting their hand in 0 freezing water (stress) vs. warm water (control), while the D2 required the subject to find all d:s with two lines among other symbols under time pressure (stress) vs. no time pressure (control). As you can see from the plots below, the signals collected from the Empatica E4 sensor differ from the lab equipment:

To determine whether these variations were significant a stress classifier was trained on the lab-quality equipment and validated on the E4 data.

Not sure what happened with that Naive Baye's classifier...
> 3 votes

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Tags: methodology
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# Question
Title: Which personality trait(s) characterize high need for external validation?
Some background to explain my question: I recently overheard a conversation, between two men working in the same firm. One of them (A) is thinking about finding a new job, as he is not happy where he is. The other (B) says "A, you have very valuable skills in this, nobody else knows as much as you do about this! You will have no problem at all finding a better job!"

I can see and hear that A is very hesitant to find a new job, he looks uncertain and not convinced that he will indeed find a better job. A says he feels a need for external validation. A does not seem to have low self-esteem, so the need for external validation seems to be unrelated to self-esteem.

**In the Big 5, which personality trait(s) would explain such a need for external validation?** Neuroticism and agreeableness might be able to answer the question, but that depends on the following:

* Would a high-neuroticism low-agreeableness person crave for external validation?
* Is high agreeableness alone enough to make someone crave for external validation?
* Is high neuroticism alone enough to make someone crave for external validation?

# Answer
The Big Five model (OCEAN) of personality is based on statistical analysis of a person's tendency to agree or disagree with short descriptive statements, and consists of the following component dimensions:

1. **Openness to experience (O):** general appreciation for art, emotion, adventure, unusual ideas, imagination, curiosity, and variety of experience.
2. **Conscientiousness (C):** tendency to show self-discipline, act dutifully, and aim for achievement against measures or outside expectations.
3. **Extraversion (E):** breadth of activities (as opposed to depth), surgency from external activity/situations, and energy creation from external means.
4. **Agreeableness (A):** general concern for social harmony and importance placed on getting along with others.
5. **Neuroticism (N):** tendency to experience negative emotions, such as anger, anxiety, or depression.

Of these, I would argue that **the trait which most directly maps on to the concept of a "need for validation" by itself would be Agreeableness.** This is the short answer.

We can, however, imagine a person who is high on Agreeableness, but for personal/cultural/religious reasons does not directly value others' approval; we can similarly imagine a person who is high on Neuroticism and experiences social anxiety, seeking others' approval to alleviate that anxiety. This can be extended to any combination of traits. These more indirect means of obtaining "need for validation" behaviors means that **it is difficult to speak confidently of any one set of Big Five traits, and only that set of traits, mapping on to "need for validation."**
> 6 votes

# Answer
In addition to Christian's answer, I want to note that it may be of further interest to examine the Big Five *Aspect Scales*. This may provide an additional level of analysis with further potential precision.

The quoted text below is taken directly from the Wikipedia entry on the subject (though you can read CG DeYoung's original paper as well):

> "The Big Five Aspect Scales is a personality test that further develops the big five personality traits test model by adding two "aspects" to each trait. Aspects represent a level of precision between the big five personality traits and the facets of the Revised NEO Personality Inventory.
>
> The aspects include:
>
> * Openness/Creativity and Intellect for **Openness**;
> * Orderliness and Industriousness for **Conscientiousness**;
> * Enthusiasm and Assertiveness for **Extraversion**;
> * Politeness and Compassion for **Agreeableness**; and
> * Withdrawal and Volatility for **Neuroticism**."

The particular aspect of Neuroticism that may be likely to contribute would be Withdrawal, or the tendency toward anticipatory anxiety.

The breakdown of Agreeableness into Compassion and Politeness may also provide some insight, considering that compassionate people may be driven by a desire to help others avoid experiencing negative emotion, and that polite people may be driven by respect for authority and desire to avoid conflict themselves.

(Please note that I did not structure this as a direct answer to your questions because it was only intended to be a comment on a previous answer.)

<sub> DeYoung, C. G., Quilty, L. C., & Peterson, J. B. (2007). Between facets and domains: 10 aspects of the Big Five. Journal of personality and social psychology, 93(5), 880. \[PDF\] </sub>
> 1 votes

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Tags: personality
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# Question
Title: Is the Myer Briggs Type indicator (MBTI) a reasonable scientific theory?
**Background:** MBTI stands for Myers-Briggs Type Indicator. It's a theory that suggests that people can be divided into 16 types, based on the way they percieve and analyse information (whether they make decisions based on logic or their feel, rely more on intuition or direct sensoric perception, and whether they are more on judging or percieving approach to things happen).

All of these "preferences" are fit into the "consciousness model" in the way, in which you can understand the appearance or behavior of a certain "type" by looking what are the dominating preferences (feeling against thinking, sensoric perception against intuition, judging vs percieving).

For a comprehensive overview, see the wikipedia article on the MBTI. Go here for another discussion of the MBTI.

### Questions

* Does the MBTI have a fundamental background?
* Were there any scientific experiments conducted?
* Are there any "type" theories that are based on actual brain research?

# Answer
> 19 votes
From what I remember, the MBTI has been compared in some studies to the Big Five (or OCEAN) model of personality. If you've not heard of it, the Big Five is the primary theory of personality that is accepted by researchers who do this sort of thing. Here are some papers comparing the two approaches:

Recent comparison and another.

The main point is that a number of the MBTI traits are correlated with the Big Five traits, though the MBTI can be criticised for various reasons (e.g., it's binary approach to personality). I think from what I remember is that the main criticism revolves around the fact that the MBTI has no place for neuroticism whereas the Big Five does.

That should be enough to get you started (e.g., reading their intro and seeing where this has been cited). There's also a somewhat useful infographic available here.

# Answer
> 8 votes
The MBTI is based on Carl Jung's work with psychological types. However, Jung's work led to the formation of analytic psychology. This work is often associated with clinical observations and anecdotes instead of controlled scientific study. This means that Jung didn't carry out research that can be considered conclusive and scientifically validated. However, I'm not sure if any of his theories can be or have been supported by research done by other people.

That said, the purpose of the MBTI is not to be a scientific theory. Going back to its history, it was meant to determine jobs that would be most suitable for women entering the workforce in the United States during World War II. It's assumed that the person taking the assessment is answering the questions honestly. Also, the MBTI results don't indicate ability or aptitude, but preferences. The MBTI has been used by human resource departments and managers to gain some high level insights into their staff and potential methods for structuring organizations and leading teams. Employees have also used the MBTI for determining possible career directions that they might be more likely to have a preference for.

# Answer
> 5 votes
Absolutely not. And, unlike claimed in other answers, it's about as based on Carl Jung as me whistling out of tune would be "work based on Mozart."

The MBTI was "developed" by a "psychic medium" who read books on Jung and spoke to him twice, much to his chagrin. He later actively avoided her. Furthermore, Jung himself cautioned against using his Personality Types as anything but a foundation for research, as the book and his further writings were based on anecdotes and clinical observation, not research in the scientific sense. He, himself, called it "Eine filosofische Excursio", "a philosophical trip".

The MBTI is an overly simplified pop-sci attempt at a personality inventory. Its type descriptions are written in the form of Barnum texts, texts that most people might find applicable to them. It is assessed through self-evaluation and strongly skewed by the expectations of those who take it. This, too, makes those Barnum Texts stronger ("Do you think often?" "Yes" "You're a thinker" "Wow, you're sooo accurate in your assessment of me").

Since the test is also binary ("Do you like Apples?" doesn't lead to a conclusion about how much someone likes Bananas) and does not control for socialised or pathological answers, it is hopelessly useless.

* Saunders, F. W. Katherine and Isabel: Mother’s Light, Daughter’s Journey. Palo Alto, CA: Consulting Psychologists Press, 1991
* Stricker and Ross (1962). Also: Stricker, L. J. & J. Ross. “An Assessment of Some Structural Properties of the Jungian personality Typology.” Journal of Abnormal and Social Psychology, Vol. 68 (1964), pp. 62-71.
* Carskadon, T. G. “Clinical and Counseling Aspects of the Myers-Briggs Type Indicator: A Research Review.” Research in Psychological Type, Vol. 2, No. 4 (1979a), pp. 2-31.
* Sipps, G. J., R. A. Alexander, and L. Friedt. “Item Analysis of the Myers-Briggs Type Indicator.” Educational and Psychological Measurement, Vol. 45, No. 4 (1985), pp. 789-796.
* Dickson, D. H. and I. W. Kelly. “‘The Barnum Effect’ in Personality Assessment: A Review of the Literature.” Psychological Reports, Vol. 57, No. 2 (1985), pp. 367-382.
* Auerbach, E. “Not Your Type, But Right for the Job.” The Wall Street Journal, January 6, 1992, editorial, p. 11.

# Answer
> 1 votes
> Does the MBTI have a fundamental background?

Yes. It is based on Jung's work, later published as Psychological Types (Collected Works, Book 6). Katherine Briggs, Isabel Myer's mother, did the initial work via communication with Jung. Like Jung, she had different theories at first, but dropped them when she heard of Jung's research on the subject. She developed the Attitude Type and four functions into a consistent theory (further than Jung did, at least at first). She also added the external function indicator as she was focused on getting jobs for women, and the externalized function was seen to be a major component. Its importance was shown even more strongly by Keirsey's work on Temperament Theory.

> Were there any scientific experiments conducted?

If by "scientific" you mean objective, verifiable tests, the answer is no. Currently, at least, that is impossible, being the perception of the Attitude Type and functions are subjective.

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Tags: social-psychology, personality, measurement, jung
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# Question
Title: Definition of valence, arousal and dominance
According to Russel's core affect framework an affective state can be decomposed into valence, arousal and dominance. How would you define these three terms (e.g. when looking at pictures)? I would define valence as the pleasure (positive / negative) and arousal as the activation level. But regarding dominance I'm absolutely unclear what this is...

# Answer
> 3 votes
These concepts (valence, arousal and dominance) are fairly standardized in the emotional investigation.

What do you mean by valence? Although at first the emotions could and were classified as positive and negative or as pleasurable and unpleasant both the relationships between the emotions themselves due to their **nature (evolution characteristics, etc.)** (they are not part of a continuum in which they are placed at the extremes but every emotion it functions independently) as the **relationship with the person who experiences** them make it pass from the pleasant or unpleasant classification to the concept of valence.

With arousal refers to the old classification as **intensity of the stimulus** although there are more in a hundred psychosomatic aspects.

Dominance, tension and kinetics are added to these concepts. In particular dominance would be in relation to the concepts of **control and again this concept is related to psychosomatic aspects**.

You have a document that goes deeper: http://www.levenswerken.eu/flash/pleasure\_arousal\_dominance.pdf

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Tags: emotion, arousal
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