# Question
Title: What are popular rationalist responses to Tversky & Shafir?
In the early 90s Tversky & Shafir observed several violations of rationality in human participants, in particular violation of the disjunction effect and sure-thing principle. This has lead to much work on questioning the rationalist assumptions of *Homo economicus*.

### Example

An example of the violation they saw was in the Prisoners' dilemma: if a person knew their partner defected then also defected (only a 3% cooperation rate), if a person knew their partner cooperated then they usually still defected (only a 16% cooperation rate). However, if they were not sure if their partner defected or cooperated, then they cooperated at much higher rates (a 37% cooperation rate). This violates the naive rationalist expectation of some % between 3 and 16 in the unknown-condition case.

Shafir & Tversky explained this effect through *quasi-magical thinking*. Even though the participants knew they had no causal effect on their partner's choice, when the choice was unknown they still "did their part" to cause a favorable outcome.

Note that given the false-belief that your actions magically effect the outcome of the other participant's decision, it is no longer irrational to cooperate at a higher rate when you don't know the partner's decision.

### Question

However, *H.econ* is still a popular model in economics. For some, this is a pragmatic choice ("the assumption holds in most situation and allows us to build nice models, so we are okay with it being broken *sometimes*"), but others have strong justifications for why rationality is still a good principle. What is a popular way for rationalists to defend against the apparent violations of rationality brought up by Tversky and Shafir that go beyond false-beliefs or quasi-magical thinking?

### References

Shafir, E., & Tversky, A. (1992). Thinking through uncertainty: Nonconsequential reasoning and choice. Cognitive Psychology, 24, 449-474. PDF

Tversky, A., & Shafir, E. (1992). The disjunction effect in choice under uncertainty. Psychological Science, 3, 305-309.

# Answer
> 19 votes
I know 2 explanations to such seemingly irrational behaviour in cognitive science. Both of them don't really justify the usage of the simple reward-maximizing model in economics.

## Rule Rationality versus Act Rationality

**Act Rationality** is the notion that **every decision** an agent makes is made in order to maximize his utility. **Rule Rationality** is the notion that decision making follows rules. These rules are rational, in the sense that among all possible rules, the chosen rule is the one that **on average** (over choices made) maximizes the agent's utility. Importantly, not every decision is optimal.

In the example you stated, this can be seen as the following: Usually, my actions towards others affect their actions towards me. In this specific game it is not the case, but people cannot take that into account, because of their rule. Their rule says "Assume people are good, try to cooperate, and defect only as a last resort, or if the gain is very high". If they are told explicitly what the other player has chosen, than it is obvious that their choice cannot affect his (so they compute the utility of both choices and choose the higher one). If they're not told the other player's decision, then they assume their decision will affect his to some extent, **because that is the way it usually works in the real world**.

This explanation is closely related to the concept of '**Bounded Rationality**' that assumes rational decisions with some bounds on the amount of information or processing power.

### Relation to Homo economicus

This explanation contradicts the assumptions of *H.economicus* \- Actions are not taken to optimize a utility function in every situation. Actions are taken according to rules (that are themselves optimized perhaps during evolution to optimize **average** reward).

## Unknown optimization function

People choose optimally, just not trying to optimize what you think they are.

For example, if we add some 'reputation' that the agent has, and he is also worried about how his choice will affect (in addition to minimizing the time spent in prison, in the prisonner's dillema), perhaps we can explain the result you mentioned. When the 'time in prison' outcome is clear (other person's choice is known) then it gets a high weight in the combined optimization problem. When the 'time in prison' outcome is not clear (other person's choice is not known) then it gets a smaller weight (no point in working too hard to optimize goals you can't predict) and the reputation result (I want to be perceived as a 'good'/'cooperating' person) is given more weight.

This explanation is more 'rationalistic' by nature: It **assumes** behaviour is an optimization problem - we (the experimenters/scientists) just don't necessarily know the optimization function.

### Relation to Homo economicus

This explanation is somewhat consistent with H.economicus. The problem is, we don't know the utility function in the general case. It can be very complex, and take into account different factors in different situations. This means that the H.economicus' basic assumtion (optimizing some utility function) is correct, but it makes the model less useful by making the specific function used not known in the general case.

# Answer
> 11 votes
*@OfriRaviv provided a great answer, but I thought I'd add a third alternative I am aware of for completeness.*

The Tversky & Shafir result is only a violation of classical probability. This approach to probability usually goes unquestioned (since people often assume classical logic is the only reasonable logic), but could be put under scientific scrutiny. In physics, this scrutiny lead to the development of quantum mechanics and the associated non-commutative (or free) probability (see also: more technical lecture notes).

Recently, this approach has also been pursued in cognitive science (most notably by Jerome R. Busemeyer) to develop a theory of quantum decision-making. Note that this approach does not assume that the brain is quantum mechanical in the physics sense, instead it questions if the assumption of classical logic is reasonable, or if human behavior is better modeled by non-Kolmogorov probability.

In this setting, the behavior displayed by humans is rational in accordance to their system of probability. This is similar to, but subtly different from, rule-rationality versus act-rationality in Ofri Raviv's answer. In particular these dynamic models of decision-making can explain the observed 'violations of rationality' in Tversky & Shafir.

### References

* Busemeyer, J. R., Wang, Z., & Townsend, J. T. (2006) "Quantum dynamics of human decision making." Journal of Mathematical Psychology, 50, 220-241. \[pdf\]
* Pothos, E. M. & Busemeyer, J. R. (2009) "A Quantum Probability Explanation for Violations of ‘Rational’ Decision Theory". Proceedings of the Royal Society B, 276 (1165), 2171-2178. \[pdf\]
* Busemeyer, J. R., Pothos, E. & Franco, R., Trueblood, J. S. (2011) "A quantum theoretical explanation for probability judgment ‘errors’". Psychological Review, 108, 193-218. \[pdf\]

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Tags: rationality, decision-making, economics
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# Question
Title: What are the major changes in the APA Publication Manual from 5th to 6th editions?
A lot of journals use APA style for journal article submissions. In 2009 APA released the 6th edition with several changes to the 5th edition.

* What's a good summary of the important changes in the 6th edition?
* Or, alternatively, what is a good online resource listing these changes?

# Answer
> 5 votes
If you're going to be submitting articles to APA journals you should have access to the APA Publication Manual 6th edition. And it is useful to use a template (see here for discussion of 6th edition LaTeX packages) and a citation system that supports the rules.

There are changes that permit new things (e.g., longer abstracts, bullet lists, and keywords are permitted, single-spaced tables) and there are new suggestions (e.g., stronger encouragement to report confidence intervals; you can say "subjects" if you want; "I" and "we" are recommended over "the researchers"). However, if you already know the 5th edition, then changes of particular interest are those where compliance with the 5th edition would actually lead to violation of 6th edition rules.

### Changes that stood out to me:

* Provide two spaces at the end of sentences (but this doesn't make much sense if you use LaTeX)
* Formatting of headings have changed and are simplified so that five-heading papers have the same first four headings as four-heading papers
* Figure captions are now placed on the same page as the figure below the figure.
* Tables and figures now appear before appendices
* Footnotes are now placed on the same page that they are referenced.
* Report p-values to two or three decimal places exactly and those less than .001 as `p<.001`.

### References changes that stood out to me:

* Include city and state for book publishers even if city is well known
* Provide DOI with any references that have a DOI

### General summaries of changes from 5th to 6th edition

Of course there are lots of little changes, check out some of these references for some other reviews of changes and resources:

### References

* Hughes, G., Onwuegbuzie, A., Daniel, L., and Slate, J. (2010). Editorial: Apa publication manual changes: Impacts on research reporting in the social sciences. Research in the Schools, 17(1). PDF

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Tags: publication-process, apa-style
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# Question
Title: Defining shyness towards strangers in confrontational situations
First of all, I would like to stress that I am **not** a cogsci person and I have almost no background in those areas of science.

The question is whether there exists a definition of a phenomenon I recently encoutered: A person is shy, but **only** in confrontational situations - has no **social phobia** regarding making friends and so on. Furthermore, this "shyness" is only demonstrated towards strangers, i.e. the person in question has no problem confronting somebody they know. Lastly, the problem occurs only in person, not over the Internet or telephone.

All in all, the question is - is this phenomenon described somewhere? And most importantly - does it have a name? Maybe it has already been defined and studied by someone.

---

### Meaning of confrontational

By 'confrontational' I mean 'having different opinions' or 'having to sort out a disagreement'. To provide an example illustrating the problem:

* After being ripped off at a restaurant (food bad, late, cold, etc), the person prefers to let the whole thing go and pay rather than argue with the waiter (thus avoiding an in-person confrontation). But,
* If the person were ordering a pizza over a phone and it did not arrive for an hour, they would have no problem calling the restaurant and discussing the problem.

I'm not a native speaker :) Hope the above description clarifies the problem a little bit.

# Answer
That sort of non-confrontational attitude has been researched as an aspect of interpersonal conflict-resolution style/mode/behaviour. The bulk of the research seems to have been conducted in the field of organisational psychology (which is not my field) since it's particularly relevant to how business is conducted.

From what I've been able to glean from Google Scholar, Blake and Mouton were the first to publish on this topic, defining five interpersonal conflict-handling styles: competing, collaborating, compromising, **avoiding**, and accommodating. Avoiding is simply defined as withdrawing from the conflict situation. Since then other researchers have developed a number of alternatives. The Thomas-Kilmann version dropped one style, compromising, and placed the rest along two dimensions, assertiveness and cooperativeness. This is the result:

Based on your description, your friend could be described as having an **avoidant conflict-resolution style** when dealing with strangers.

This is an interesting topic for me because I'm somewhat like your friend. I'm quite introverted and I suspect your friend is too to some degree, since there is a link between introversion and having an avoidant interpersonal conflict-resolution style.

In business contexts it's not surprising to find that people who show a high need for dominance are averse to using an avoidant conflict-resolution style.

I'm not sure what the research says about why your friend might choose a different style of conflict-resolution with friends. I'll see what else I can find.

**References**

* Blake, R.R & Mouton, J.S. (1964). *The Managerial Grid: The Key to Leadership Excellence*. Houston: Gulf Publishing Co.
* Thomas, K.W. & Kilmann, R.H. (1974). *The Thomas–Kilmann mode instrument*. Tuxedo Park, NY: Xicom
* Schneer, J.A. & Chanin, M.N. (1987). Manifest Needs as Personality Predispositions to Conflict-Handling Behavior. *Human Relations, 40*, 575-590
* Wood, V. F., & Bell, P. A. (2008). Predicting interpersonal conflict resolution styles from personality characteristics. *Personality and Individual Differences, 45*(2), 126-131.
> 6 votes

# Answer
(caveat: I am not a trained psychologist, so talk to one before taking any advice from people online!)

This isn't really a definition that I know of for this (beyond social phobia, or confrontational anxiety), though that's not a bad thing. Something that exists does not need a label to exist, and labels often shortcut and/or constrain our mental processing of a thing.

So, from a psychology perspective (not a CogSci one; just being explicit), there's probably a good chance the person has had multiple negative experiences with regards to `confrontation` and `in-person communication`.
The brain has a remarkable ability to create discrete boundaries around fuzzy relational systems, so I suspect that whomever this person is, there is a perceived threat (most likely subliminally processed) which stimulates the anxiety. In-Person communication is very different from vocal-only communication, and would include a lot more visual and social processing, which in turn can bring up mental links to past experiences that match what's being processed in the moment. If there are negative associations with those visuosocial links, you'll experience anxiety due to the possiblity of a repetition.

Is the person from a restrictive, socially conservative culture? Is there a history of controlling and/or fickle parents? Or a long time spent in/around aggressive, insecure people who personalize everything? These (and a lot more!) are all things that can create the sort of anxiety you're describing.

But really, a trained psychologist is whom this person should be talking with. A trend like this can result in intense social isolationism unless addressed early.
> -1 votes

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Tags: terminology, social-psychology
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title: Study on commitment and follow-through

text:
# Question
Title: Study on commitment and follow-through
I'm faced with a UX problem of looking for ways to position a website to increase attendance at future "real world" events, and I'm remembering a study once conducted along these lines (details a bit hazy):

*University students were given a presentation on the benefit of receiving flu shots and instructed on where to go to get them. One session's group received no further materials, while the other's group were given a map and asked to pick a time to report. The attendance rate in the latter group was substantially higher than the former.*

I can't seem to find mentions of it online anywhere, though, and if anyone could point me towards more information on this or any other related study it would be highly appreciated.

# Answer
> 10 votes
The study you are looking for is

> Leventhal, H., Singer, R., & Jones, S. (1965). Effects of fear and specificity of recommendation upon attitudes and behavior. *Journal of Personality and Social Psychology*, *2*(1), pp. 20-29. doi: 10.1037/h0022089

The study is mostly how you remember (though it was tetanus instead of the flu). Critically, the manipulation was intended to increase the the availability of receiving a tetanus shot by having rehearsed the steps needed to get one. Students were given a map of the campus with the health center circled, and were asked to review their schedule and find a time they might be able to go--however, they did *not* make an appointment. Thus, the commitment was only to themselves.

There are, of course, a wide variety of ways to increase consumer compliance, including the foot-in-the-door strategy, door-in-the-face strategy, and framing effects to name a few.

There is a wide body of literature in social psychology on the idea of influence. I highly recommend two books on the topic, both of which are leisure reads:

1) Nudge by Richard Thaler and Cass Sunstein (which mentions the Leventhal study!)

2) Influence: Science and Practice by Robert Cialdini. There is a chapter specifically on Commitment (ch 3) which also talks about the classic foot-in-the-door paper (below), more in line with the commitment strategy you suggest.

> Freedman, J.L., & Fraser, S.C. (1966). Compliance without pressure: The foot-in-the-door technique. Journal of Personality and Social Psychology, 4, 195-202.

# Answer
> 7 votes
I've found an article by O'Keefe and Jensen (2007) that seems somewhat relevant. It's a meta-analysis that finds, according to their abstract (p. 623):

> "...in disease prevention messages, gain-framed appeals, which emphasize the advantages of compliance with the communicator’s recommendation, are statistically significantly more persuasive than loss-framed appeals, which emphasize the disadvantages of noncompliance."

The difference appears quite small, however; maybe not what you were looking for.

Reference:

O'Keefe, D. J., & Jensen, J. D. The relative persuasiveness of gain-framed loss-framed messages for encouraging disease prevention behaviors: A meta-analytic review. *Journal of Health Communication*, *12*, 623-644.

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Tags: terminology, reference-request, social-psychology, commitment
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# Question
Title: Bias by which we tend to accept vague descriptions of ourselves
There's an effective strategy employed by horoscopes and "psychics" where they say vague statements like "You like being with friends but you value your time alone"; statements that basically "cover their bases" in multiple extremes and thus apply to just about anyone.

As a typical example in high school our Psychology teacher gave us a "handwriting evaluation" which gave our "personality types" based on our handwriting; the results were just random statements. Everyone got the same statements but most of the class claimed their results were accurate.

What is the name of these types of statements or the bias by which people tend to believe them?

# Answer
> 10 votes
This is referred to as The Forer Effect after Bertram Forer. Wikipedia describes it accurately:

> The Forer effect (also called the Barnum Effect after P.T. Barnum's observation that "we've got something for everyone") is the observation that individuals will give high accuracy ratings to descriptions of their personality that supposedly are tailored specifically for them, but are in fact vague and general enough to apply to a wide range of people. This effect can provide a partial explanation for the widespread acceptance of some beliefs and practices, such as astrology, fortune telling, and some types of personality tests.

Forer gave the results of a "personality test" to a group of his students composed of random vague statements compiled from horoscopes. Students were asked to rate it's accuracy on a scale from 0 to 5, and the mean score was 4.26.

Forer discussed these findings and the "experiment" in his article The fallacy of personal validation: a classroom demonstration of gullibility.

# Answer
> 7 votes
Confirmation bias (Wikipedia) also seems relevant:

> Confirmation bias (also called confirmatory bias, myside bias or verification bias) is a tendency of people to favor information that confirms their beliefs or hypotheses. People display this bias when they gather or remember information selectively, or when they interpret it in a biased way. The effect is stronger for emotionally charged issues and for deeply entrenched beliefs. For example, in reading about gun control, people usually prefer sources that affirm their existing attitudes. They also tend to interpret ambiguous evidence as supporting their existing position.

People have various beliefs about themselves, and automatically seek confirmation for them. A vague description can be interpreted in many ways, and if people are presented with a vague description of themselves, they are likely to pick an interpretation on the basis of its compatibility with their previous beliefs. Since any vague statement was interpreted by searching for the most accurate-seeming meaning, it will be deemed accurate almost by definition.

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Tags: cognitive-psychology, terminology, bias
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# Question
Title: Why do dual N-back games use certain letters?
Every implementation of dual n-back that I've ever seen uses the set of letters 'C', 'H', 'K', 'L', 'Q', 'S', 'R' and 'T'.

Why is that?

# Answer
> 5 votes
The set is not always the one you suggest. There are many implementations that don't even involve letters, but use random shapes, numbers, spatial locations, or other stimuli.

In Jaeggi et al., 2007, they used spatial locations for the visual task, and

> The auditory material consisted of eight German consonants (c, g, h, k, p, q, t, and w) spoken in a female voice and **selected on the basis of their distinctiveness**.

(emphasis mine).

In Takeuchi et al. 2010, they used numbers and locations:

> “Dual” N-back task. In this task, the number stimuli consisted of numbers, 1 to 4, presented in a random sequence in one of four places on a line.

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Tags: intelligence, memory
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# Question
Title: How are newly created neurons recruited into existing networks?
As far as I understand, the basics of neurogenesis (abstracted down to the level that makes sense to a computer scientist) is as follows:

1. Neural progenitor cells differentiate into new neurons that have zero (or very few) synaptic connections, but are sensitive to the local chemistry.
2. *(Optional)* Sometimes (such as in adult neurogenesis in the olfactory bulb) these immature neurons-to-be are produced far away from where they are needed and follow standard pathways to migrate to the correct brain region
3. The immature neuron extends dendrites towards upstream neurons and starts to develop an axon
4. The immature neuron extends axon towards downstream neurons, and
5. The neuron matures and becomes indistinguishable from the network it joined.

I've eliminated many of the biological details, since I want to just capture the details (more info). The part that seems to be not well described, and **my question, is**:

* How do neurons select where to make their initial dendrite and axon connections?
* How/when does a given network notify the progenitor cells that they should differentiate?

---

### Partial results

Cecchi et al. (2001) proposed a model where the new neurons produce initial connections randomly, and then the only the ones that contribute to the function of the network end up firing frequently and surviving, and the rest die. This inspired by the observation of high death rate among immature neurons. However, there is not biological evidence to support that the initial connections are in fact random, and I hope that there has been more evidence gathered since the early work in 2001.

### Notes

* This question is motivated by the search for computational models with a biologically reasonable account of neurogenesis.
* I am looking for some sort of abstract local explanation to my questions at-least at the rule-of-thumb level. For examples, if I was asking about plasticity of established connections (and not neurogenesis in particular), then Hebb's "neurons that fire together wire together" would be a sufficient answer, although STDP would be a better one. However, I do not need all the biological details, just the high level rule if one is known.

### References

* Cecchi GA, Retreanu LT, Alvarez-Buylla A, Magnasco MO – “Unsupervised Learning and Adaptation in a Model of Adult Neurogenesis” Journal of Computational Neuroscience; 11:175-182; 2001 \[preprint\]

# Answer
There is a huge body of literature on axon growth cone guidance which will give you some insights into how the biology works. Unfortunately, incorporating it all into a model is probably going to make it unwieldy unless your express purpose is to model the physiology, which doesn't seem like the case.

Here are some references:

> Hong K, Nishiyama M. (2010). From guidance signals to movement: signaling molecules governing growth cone turning. Neuroscientist, 16(1),65-78.

This is pertinent because it explicitly mentions adult neurogenesis, as much of the subject is devoted to the developing nervous system in models like the developing chicken.

> Kolodkin AL, Tessier-Lavigne M (2011). Mechanisms and molecules of neuronal wiring: a primer. Cold Spring Harb Perspect Biol, 3(6), 1-14 Free PDF

To call Marc Tessier-Lavigne a leader in the field of neuronal growth would be an understatement. This article also covers some of the cues of synaptogenesis as well.

> Simpson HD, Mortimer D, Goodhill GJ (2009).Theoretical models of neural circuit development. Curr Top Dev Biol, 87, 1-51.

Regrettably, I do not have access to this article, but it appears to be more along the lines of computationally realistic representations. It does state that their models for synaptic strengthening are based on Hebbian Learning, so that's at least in line with what you presumed that you needed.

In searching for more computational models, ephrins and integrins are two of the cell surface agents that are heavily involved in the process, so any abstractions of those would make for a good model.
> 22 votes

# Answer
For the dentate gyrus, which is probably more closely analogous to a feedforward hidden layer in a memory network, here are some answers:

1. Axon and dendrite connectivity is essentially local and can probably be assumed to be initially random within that local region. That is, a neuron integrating into the DG at the midpoint (along the long hippocampal axis) will have its dendrite arborize in that same location, thus receiving cortex inputs from the region of the cortex that topographically projects to that area. Likewise, its axon will target CA3 neurons at the midpoint of the hippocampus. For this reason, the general connection statistics of a newborn neuron will ultimately be similar to a neighboring neuron; though the (likely) competition between young and old synapses and the high synaptic plasticity of young neurons will distinguish the two neurons computationally.
2. In the DG, the rate of neurogenesis is regulated by some external conditions, such as running and (likely) affect/mood. These can probably be thought of as predictive indicators of future need of neurons. Network activity is probably more critical for the survival of neurons.
3. The OB is most likely at least somewhat different on both these points. One should take into account that newborn OB neurons are not "typical" neurons (in the abstract NN sense) by any means; OB-GCs rely more on dendro-dendritic communication (no axon) and are inhibitory.
> 7 votes

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Tags: neuroscience, neural-network, theoretical-neuroscience, plasticity, neurogenesis
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# Question
Title: Is it easier for people to remember longer words than words mixed with symbols?
I'm doing a study on why it is difficult to remember passwords. I would imagine that it would be easier for people to remember a password like "strawberryhouse" than "$tr@wb3rr!", even though the former has more characters.

Is there any research that backs up that idea?

# Answer
> 9 votes
One basic explanation would be a chunking one -- that it's easier to combine several words into a single memory unit than letters and numbers. In 2000, Alan Baddeley proposed the episodic buffer as an important component of the working memory (WM) system. According to Baddeley, the episodic buffer imbues WM with the ability to join information together, even when that information is of different modalities (e.g., sight and sound). Even though "$tr@wb3rr!" may be as memorable as the word "strawberry," with enough practice "strawberryhouse" can be just as facile (and a stronger password to boot).

Another concern is that while you'll likely always remember "strawberryhouse," only remembering the gist of the alphanumeric password ("I remember it sounds like 'strawberry'") can lead to verbatim errors of recall ("Was it '$tr@wb3rr!,' '$tr@wb3rri,' or "$tr@wb3rry?'"). I can find some empirical support on this track if it's useful, too.

> Baddeley, A. (2000). The episodic buffer: a new component of working memory? *Trends in Cognitive Science*, 4, 417-423.

# Answer
> 4 votes
I believe this phenomenon is best viewed through the lens of the interactive activation model for word recognition (McClelland & Rumelhart, 1981), which was put forth to explain a similar phenomenon, namely the ability to more easily recognize letters within a word as opposed to to letters not comprising a word.

As the image below illustrates, this ease of recognition comes from the top down influence of the known word concepts on the possible identities of the letters.

Now, to tie this back into your original question, we can view the task of remembering a password as one of converting a stored concept into a character string (i.e. something like the interactive activation model without the bottom up line component). If your concept is "strawberry", then there's a strong top down influence to choose 's' as the first character of the password, since that's the most common first character of "strawberry". Now many have formed associations between 's' and '$', so perhaps the latter might get some response, but not nearly to the extent of the actual letter, since **letters are far more commonly used within words than symbols are**.

> McClelland, J.L., & Rumelhart, D.E. (1981). An interactive model of context effects in letter perception: I. An acccount of basic findings. *Psychological Review*, *88*, 375-407.

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Tags: memory
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# Question
Title: Cognitive explanation of why beta blockers are effective for anxiety
Beta blockers essentially reduce physical effects of anxiety and panic disorder, but there is no proof that there is a direct effect on anxiety. Some scientists believe there is an indirect effect.

What is the cognitive explanation of the fact that a reduction in symptoms causes a reduction in anxiety?

# Answer
> 3 votes
One possibility is related to the Two-Factor theory of emotion. The theory describes how emotion is a product of both cognitive and physiological factors. Essentially, the mind tries to determine what emotion it is feeling by analyzing the body. By antagonizing epinephrine, they kind of inhibit the sympathetic nervous system. So, when a person would otherwise feel anxiety it would be associated with the effect of epinephrine. Without that cue, they would possibly interpret their feelings differently, as feeling less anxious.

http://psycnet.apa.org/journals/rev/69/5/379/

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Tags: cognitive-psychology, psychiatry, psychopharmacology
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# Question
Title: What transient factors affect performance on IQ tests?
While performance on intelligence tests aim to measure an underlying relatively stable trait, there are presumably a range of transient factors that could temporarily lower or possibly even raise scores on such tests.

Possible factors might be: alcohol, sleep deprivation, mood, test taking anxiety, etc.

* Are there any studies so far that have assessed the degree to which such transient factors can influence performance on intelligence tests?
* Do such studies suggest such affects depend on other factors such as gender, personality, and presence/absence of ADD/Asperger's?

# Answer
I had a course which was about IQ; I never read an article about it, so I can't quote studies (I can look up the references if you like).

There are indeed a lot of factors that can influence ones score on an IQ test. These are some transient factors that came to my mind:

* The setting: was the test taken at home, at school, at a totally unfamiliar place? Test scores tend to be higher when a child can take it at home.
* The part of the day: was the test taken in the morning, in the afternoon, or in the evening? I think (I should look this up) that scores tend to be lower if IQ tests are taken in the evening. Perhaps if you're a morning type, you're better in the morning than 'evening people', who are better in the afternoon than in the morning. But this is speculation (I know I've read *something* about it, but I can't seem to find it now).
* Motivation/Attention: this really can play a big role in the results. That's why good tests (e.g. the WISC) have a zone for remarks. Children with ADHD score better when they are given more pauses during the examination.
* Hormones: there is some evidence that there's a hormonal influence (testosteron, estrogen, congenital adrenal hyperplasia).
* Test taking anxiety: this can indeed influence the score negatively. It's important that the test leader says 'good job' or something like that. Normally, this isn't according to the guidelines of the test, but it's acceptable here, since you would underestimate the ability.
> 9 votes

# Answer
Here are two transient factors I know (but there definitely are more!):

* The color red (either presented as a color, or as a word) induces an avoidance motivational state, leading to an impaired IQ test performance \[1\]\[2\]
* Stereotype threat: Inducing a negative stereotype of a group (e.g.: Women are bad at math) causes members of this group actually to perform worse. This works with gender, race, age, etc. \[3\]\[4\]

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\[1\]: Elliot, A. J., Maier, M. A., Moller, A., Friedman, R., & Meinhardt, J. (2007). Color and psychological functioning: The effect of red on performance in achievement contexts. Journal of Experimental Psychology: General, 136, 154-168.

\[2\]: Maier, M. A., Elliot, A. J., & Lichtenfeld, S. (2008). Nonconscious avoidance motivation mediates the negative effect of red on intellectual performance. Personality and Social Psychology Bulletin, 34, 1530-1540.

\[3\]: Gerstenberg, F., & Imhoff, R. (in press). 'Women are Bad at Math, but I‘m Not, am I?’Fragile Mathematical Self‐concept Predicts Vulnerability to a Stereotype Threat Effect on Mathematical Performance. European Journal of Personality.

\[4\]: Smith, J. L. (2004). Understanding the process of stereotype threat: A review of mediational variables and new performance goal directions. Educational Psychology Review, 16, 177-206. doi:10.1023/B:EDPR.0000034020.20317.89
> 6 votes

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Tags: intelligence, measurement
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# Question
Title: How to efficiently locate existing psychology and social science measures?
Whenever I start a new research project, I typically have to find questions and scales that have proven validity in measuring constructs of interest (e.g., psychological / political science / social science scales). This can often be quite time consuming, and often there are issues of cost and copyright to consider.

### Questions

* What are general tips for efficiently and cost effectively locating measures for a given construct?
* Are there any databases that make it easy to locate such measures?
* Is there anything like a StackOverflow/PatternLibrary/Best Practices compendium of measures or advice on locating measures?

# Answer
The APA has a general tutorial on finding psychological tests with a range of tips.

### Finding measures

* PsychTESTS is a new product by the APA that aims to make it easier to find psychological tests. It is a subscription service. Thus, you would probably have to pay for it yourself or get it through a university or other body that subscribes to it
* **Read the method sections** of the articles that you are incorporating in your introduction and literature review. If you are going to do research you'll need to familiarise yourself with existing research. See what measures have been used in the past.
* **Ask a question on cogsci.se**: Well formulated questions asking for recommendations for measuring particular psychological constructs are welcome on this site.

### Measures on a budget

* Some tests are free to use. Academics and others often make such tests available on their website (e.g., the IPIP).
* For tests developed by academics, you can often just contact the academic by email and ask for permission to use the test. Be clear, be polite, be professional. In some cases they might ask that you share any data from the test with them.
* For commercial tests, you may wish to contact the publishers to find out whether they permit free or discounted use for research purposes.

### Whether to create your own test

Also as a general point, there is often a decision between whether to buy a test or build your own. Sometimes, the construct being measured is sufficiently novel, that there is no existing measure. However, if the construct does have an established and validated measure, there are strong arguments to use it. Building a well validated psychological test takes substantial time and resources.
> 5 votes

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Tags: measurement, reproducible-research, test, reference-request
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# Question
Title: What neurobiological changes are associated with the end of the critical period in children?
Developing children are in a critical period during which they are much better at learning certain tasks like speaking a language. After the critical period ends, children have a qualitatively more difficult time learning these tasks.

**What specific changes in a child's brain are responsible for the drastic difference in learning during and after the critical period?** Are these changes just to the plasticity and rate of neuorogenesis?

### Notes

* The best understood critical period is phoneme recognition and production; I am fine with answers that are specialized to this task.
* It is important to explain how the neurobiological changes produce a change in learning that seems so *qualitatively different* and *sudden* compared to the gradual decreases in learning at other times.

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### Related questions

How is a young child able to learn language so easily?

Why does neuroplasticity decrease in adults?

Computational models of early learning in children

# Answer
> 3 votes
The truth is, we don't fully know. There are likely a number of factors. One of them seems to be the Brain Derived Neurotrophic Factor (BDNF). This molecule seems to be involved with maintaining and encouraging neuron growth. In Rats with a transgenically accelerated rise in BDNF levels, the critical period began earlier, and finished earlier as well (Huang et al., 1999). This doesn't exactly get at the heart of the question, because clearly there is some interaction between experience and expression of this gene. It's a good starting point, however.

### References

Huang, Z.J., Kirkwood, A., Pizzorusso, T., Porciatti, V., Morales, B., Bear, M.F., Maffei, L., & Tonegawa, S. (1999) "BDNF Regulates the Maturation of Inhibition and the Critical Period of Plasticity in Mouse Visual Cortex", *Cell* 98(6): 739-755. doi:10.1016/S0092-8674(00)81509-3

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Tags: neuroscience, developmental-psychology, plasticity
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# Question
Title: What causes systematic under- or over-estimation of general knowledge quantities?
**What psychological theories predict whether individuals will underestimate or overestimate when responding to particular kinds of general knowledge quantity questions?**

For instance, I have seen an unpublished study in which people were asked to guess the weight of the fuel in a certain space shuttle, and almost everyone wildly underestimated the weight. Then in another question they were asked to guess the weight of the horse which won the last Kentucky Derby and the responses were distributed fairly evenly around the truth. Why is this?

I think that the heuristics and biases literature must be relevant here, but I haven't found any citations that allow me to make predictions which are sufficiently specific.

# Answer
> 10 votes
One theory that may explain this is is Kahneman and Tversky's anchoring heuristic.

If you ask how much fuel the space shuttle needs, most people don't have the proper background knowledge to answer this accurately. Instead, they'll rely on a piece of information they do know--e.g., how much fuel a car needs--and adjust from there. Responses will be biased towards the anchor. Since a car requires very little fuel in comparison (~12 gallons), people will tend to underestimate the true response (~500,000 gallons).

If you first told them: The cruise ship The Norwegian Dream holds roughly 350,000 gallons of fuel, and *then* asked how much fuel weight the space shuttle needs, their answers will likely be closer to the truth. (Though there is the confounding variable of size-- larger vessels need more fuel, but even small vessels will need a lot of fuel to launch into space).

When it comes to horses, people have more accurate anchors-- such as a human, or an elephant-- and will tend to make more accurate judgments.

Although there are certainly more cues that people use to make size judgments, a complete theory must take into account one's background knowledge. Thus, even the anchoring heuristic is limited in that we must know what people are likely to use as an anchor for any given question.

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Tags: cognitive-psychology
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# Question
Title: Is stimulus generalization acquired due to inability to discriminate stimuli?
The classic case of Stimulus Generalization is Little Albert. The About.com link also explains it in terms of dogs. I note that in both cases, it seems highly likely that the subject (dog or infant) is *unable to discriminate stimuli* or unable to determine which *part* of the stimulus is relevant.

Have there been studies on stimulus generalization in adults?

Specifically, I wonder if stimulus generalization results from the inability to determine what part of an unconditioned stimulus (white rat) is associated with the conditioned stimulus (loud noise).

I know that discrimination can be caused by conditioning with relevant stimuli and extincting non-relevant stimuli, but would an adult human generalize fear to a general stimulus or a specific one and why?

# Answer
> 3 votes
If you think of the stimulus being represented by a distributed set of features (Tanifuji et al., 2001), then I would not say it was a *failure* to discriminate. During the conditioned response training for Albert, all features were present as the stimuli. It wasn't that he couldn't discriminate the features, just that each of the features were trained as conditioned stimuli.

I suspect that an adult would think of the rat symbolically, and the conditioning would be done on that mental rat symbol. The individual features would likely not produce fear. Children of Albert's age are not thought to have yet developed symbolic thought (DeLoache, 1987). So, the conditioning would be done on the visual components themselves.

**References**

http://anon.cs.rochester.edu/users/faculty/dana/tanifuji.pdf http://www.sciencemag.org/content/238/4833/1556.short

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Tags: behaviorism, conditioning
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title: What is Asperger's Syndrome?

text:
# Question
Title: What is Asperger's Syndrome?
I have read through the Wikipedia article on and looked at the diagnosis of Asperger Syndrome (AS) and am still not sure how it is connected with autism. It seems like compared with autism it is really hard to distinguish between an average person and someone with AS.

The only criteria seems to be that people with AS are anti-social and do not have some other more serious psychological disease. Is there some sort of way of using neuroimaging to show a significant difference in the brains of an average person and someone with AS?

# Answer
From ICD-10 (International Statistical Classification of Diseases and Related Health Problems), Asperger's syndrome (F8.45) is:

> A disorder of uncertain nosological validity, characterized by the same type of qualitative abnormalities of reciprocal social interaction that typify autism, together with a restricted, stereotyped, repetitive repertoire of interests and activities. **It differs from autism primarily in the fact that there is no general delay or retardation in language or in cognitive development.** This disorder is often associated with marked clumsiness. There is a strong tendency for the abnormalities to persist into adolescence and adult life. Psychotic episodes occasionally occur in early adult life.

Actually, the Wikipedia article that you are pointing to also makes it clear:

> It differs from other autism spectrum disorders by its relative preservation of linguistic and cognitive development.

However, there is no consensus if there is difference between Asperger's Syndrome and High-Functioning Autism. Perhaps also there is no clear distinction between clinically-significant autistic traits and complete absence of them.

Currently autism and Asperger's Syndrom alike are not fully understood on neurobiological basis (there are ongoing research, for a review see e.g. E. Pisula, The autistic mind in the light of neuropsychological studies (2010) or a special issue of Nature on autism).

However, the premise

> The only criteria seems to be that people with AS are anti-social and do not have some other more serious psychological disease.

is clearly false.
> 10 votes

# Answer
Asperger's syndrome is at the mild end of Autism Spectrum Disorders, meaning that it has similar characteristics, but in milder form. In that sense, it is between Autism and typical development. People with Asperger's are not just "anti-social", they have a *clinically significant* impairment of social interaction. They also exhibit repetitive behaviors and restricted interests (more than just "I like dinosaurs", this would be a fascination with dinosaurs to the exclusion of most other things). Importantly, like other ASD variants as well as other mental health disorders, Asperger's is defined behaviorally, not neurologically. That means the diagnosis can be made by a trained clinician on the basis of the individual's behavior, not a brain scan. Presumably, there are neural correlates, but even if we knew what they were, they would not be the diagnostic criteria.
> 3 votes

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Tags: terminology, aspergers
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title: Are there any laws of memory?

text:
# Question
Title: Are there any laws of memory?
Several years ago, my adviser wrote an article discussing the observation that a hundred years of studying memory had not resulted in the discovery of a "law" of memory. He wrote (p. 247):

> When one reads or hears the claim that “repetition improves retention” or that “generating information enhances recall” or that “forgetting follows a power function” or all other statements of the form that “variable X has a consistent effect on variable Y,” one can be certain that the claim is both true and false. It is true in that conditions can be found under which the rule holds (otherwise the claim would not be made), but false in that a skeptic can always say: “Very nice work, but your ﬁnding depends on many other conditions. Change those and your effect will go away.”

Has the story changed since 2008? Can anyone cite a proven true law of memory? If not, what's the closest thing memory has? The idea of transfer-appropriate processing is the closest I can name, is there something more substantial?

# Answer
> 5 votes
Memory is only a psychological construct. In reality there is only the brain, and the physiological functions of the brain. "Memory" is just a way to conceptualize some of these functions. For this reason, it's unlikely that a law will ever emerge. Part of the reason is that memory can refer to so many different things, biologically.

Even when you get down to the actual biology, laws are not really the standard. Biology is a messy thing and virtually no laws exist that couldn't be contradicted. Something as basic as the cell theory could be reasonably argued against. Viruses are not cellular, yet an argument could be made for them being alive. It isn't the current thinking, but it's not an absurd proposition either. If psychological phenomena are a result of biology, and no laws exist in biology, I think it's reasonable to say no laws will exist in psychology either.

Perhaps one of the strongest ideas about memory is Hebbian learning. But even that is just a simplification.

# Answer
> 5 votes
The article you cite does a wonderful job of tearing down an excellently crafted strawman. It is true that it is very difficult to meet his extremely precise measure of a "law". The two problems are *Who is proposing "laws"?* and *Why are these criteria fair*?

I have almost never heard of anyone in any psychological field posit that their theories are scientific laws. I have never seen an article so boldly state "X will cause Y in all possible cases", the brain is simply too complex and this is why research always includes information about it's sample, measure and test procedures.

A lot of effort is put into *generalizing theories* but attempting to **generalize to the level of an absolute law is impractical** and often unhelpful; maybe repetition doesn't help retention of knowledge *when the participant is on fire*. This is why the generalizability of results are always investigated and why no *sane, accredited* psychologist attempts to say their theories hold in all possible situations.

Further, the guidelines Roediger, H.L. (2008) set, specifically expecting a "Law" to stand up to variance in all factors of Jenkins’ (1979) "tetrahedral model" are compeltely unmeetable for a number of reasons.

One of the primary problems with his expectations is they require a law to generalize to images, episodic events, written words, ect. **There are different types of memory.** Episodic memory, Semantic Memory, Procedural Memory, working/short term memory vs Long Term memory, different types of memory function differently and operate in different parts of the brain. Memory loss affects different types of memory.

Anterograde and Retrograde Amnesia for example generally don't affect Procedural memory but mostly Episodic Memory.

Bottom line, Roediger, H.L. (2008) expects The Law of Apples to apply to Oranges. The reason no Law of All memories exists because different types of memory are fundamentally different, and any attempt to generalize something to all possible types of memory would be absurd.

He is right in so far as the field of memory is complex and universal laws don't exist for it, but no one active in the field seems to be *making* these assumptions. If you are looknig for these laws you are simply looking for the wrong thing, and should rather learn more basic things about memory, like the types of memory, types of learning ect, before you continue any investigation into the field.

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Tags: cognitive-psychology, memory, learning
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# Question
Title: What can cognitive psychology tell us about the results of the Stanford Prison Experiment?
One of the experiments that are always taught as prime examples of social psychology in action is the Stanford Prison Experiment

> In 1971, Zimbardo accepted a tenured position as professor of psychology at Stanford University. With a government grant from the U.S. Office of Naval Research, he conducted the Stanford prison study in which 24 normal college students were randomly assigned to be "prisoners" or "guards" in a mock prison located in the basement of the psychology building at Stanford (three additional college students were selected as alternates, only one of which participated in the study). The two week planned study into the psychology of prison life ended only after 6 days due to emotional trauma being experienced by the participants. The students quickly began acting out their roles, with "guards" becoming sadistic and "prisoners" showing extreme passivity and depression.
>
> \*from the Philip Zimbardo article

I realize there have been scores of scholarly articles written about the subject in the intervening time, but most of the abstracts dealt with the aspects of social psychology that were pertinent even in the last decade with the atrocities at Abu Ghraib.

All of that is painful yet certainly necessary to ponder, but I'm curious about the cognitive aspects of the study. What facets of, for example, motivation does this study (and others like it) bring out? What can be said about our sense of logical reasoning under these circumstances? What sorts of qualia could one use to model this behavior in an agent?

# Answer
> 6 votes
I've always thought of Stanford Prison Experiment (and Abu Ghraib) as a situation in which group think forms a sort of feedback loop. If you agree that people behave within context of a group, and the context is created by the group itself (Hogg, 1998), then you can see what is happening. The context may at first be in line with the larger group (the University, or Military, or American culture in general). Within the smaller group however, individuals may "push the limit" of acceptable behavior. But in doing so, they are changing to context of the group. For a person to "push the limit" again, would be to act in an even more extreme way. The situation feeds back upon itself.

The question remains, as you pointed out, what motivation starts this movement in the first place? There is no reason to think it couldn't feedback upon itself in the *other* direction, either. There is some underlying feeling that is amplified by this group think. In the Hogg article, the researches essentially seeded that motivation experimentally. But in a normal situation, it can be virtually anything. Intuitively, I would say in the prison experiment the initial seed was just a desire for the students to act out the roles they were given. Prisoners obey the guards. Each time the limit of acceptable behavior was pushed, the context that defined acceptable behavior was changed too.

Myers (1977) describes something similar, which he calls polarization. In his research, he showed a tendency for people to not only conform to the group standards, but also try to exceed them in, "the socially preferred direction". This phenomena, plus a tendency to act within the context of a group, can lead to runaway behavior.

**References**

http://psycnet.apa.org/journals/gdn/2/1/48/

http://www.sciencedirect.com/science/article/pii/0022103178900495

# Answer
> 5 votes
The Stanford Prison study is probably one of the greatest (and worst) experiments ever to have been carried out in the field of psychology (its social psychology, BTW).

Its worth noting that the results have been controversial given the involvement of Zimbardo himself in the study (as the warden). A much, much better study is Haslam and Reicher's replication for the BBC. This version was much better controlled and recorded, and if I were looking to model the behaviour of agents in this situation, I would probably start there.

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Tags: cognitive-psychology, cognitive-modeling
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# Question
Title: Is it possible to create a false memory by trying to remember something that eludes you?
Sometimes I have difficulty remembering the specifics of an event, specifically if I'm tired or possibly have recently consumed alcohol. A close friend of mine has gotten me in the habit of specifically trying *not to think about the details* of what I'm trying to remember if I am unclear on them at any given moment. The reasoning is, if one starts to think about varions on what happened, trying "too hard" to remember the details of an event, then one might alter one's memory by the very act of trying to remember. Instead, I try to stop thinking about the details of the specific memory, and sometimes they will just come to me suddenly (often hours r days later).

Have any studies shown such a phenomenon to exist? Is it possible to create a false memory by trying to remember something that eludes you?

# Answer
A seminal paper by Roediger and McDermott (1995) observed that studying (similar to thinking about) materials was associated with a high likelihood of false recall and false recognition of materials similar to the studied items. This research has spawned hundreds of follow-up studies, none of which address your question entirely but converge on a plausible explanation: As you try to recall the specifics of the event, you likely recall a number of things that actually occurred (e.g., you were drinking rum, there was a pretty girl in the corner, and it was getting late). Considering these true specifics, however, according to this line of research, may introduce associated memories which never actually occurred (e.g., the pretty girl winked at you). Think these thoughts long enough and you'll have what's called a source monitoring error -- that is, you'll conflate thinking about the pretty girl winking *with a memory that she actually did wink*. That might be why you feel as if you had fewer false memories when you don't consider specifics -- there are fewer opportunities to make false associations. (It's also interesting to note that repeated testing, while improving "correct" memory, also enhances false memory. I can provide more links if you're interested.) If you're interested in other things that cause false memory (at least in these laboratory studies), here's a link.

Most of this is research my group is associated with, generally because I'm most familiar with that literature. I like this line of studies (called DRM studies) because they show false memories can be generated in a matter of moments (or "the morning after"). Loftus's work is fascinating, too, because she uses more naturalistic materials, those more pertinent to real life. Definitely two sides of the same coin.

Leave a comment if I can provide more info.
> 7 votes

# Answer
Well, the real name in this field is Elizabeth Loftus, and from this study, (which I vaguely remember learning about in first year psych) it appears that suggestions by others can lead to a belief in false memories.

Now, whether or not this can happen as a result of self-suggestion is, I believe, an open question (i have anecdotal evidence for myself, but that's probably not appropriate for here).
> 4 votes

# Answer
Here are two links to a couple of Elizabeth Loftus's papers about the issue: Memory Distortion and False Memory Creation and Misinformation and Memory: The Creation of New Memories - PDF warning.
> 2 votes

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Tags: cognitive-psychology, memory
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# Question
Title: Do porn and other remotely perceived entertainments work because of Mirror Neurons?
As you might have known, Mirror Neurons are hypothetically the neuron pair - each of which is carried by other person - that make people to share their feeling although one of them just observes the action instead of take a part in the action. ( This short video is a succinct summary of this neurons, for more see this TED Talk )

the excerpt from the Wikipedia:

> "A mirror neuron is a neuron that fires both when an animal acts and when the animal observes the same action performed by another. Thus, the neuron "mirrors" the behaviour the other, as though the observer were itself acting. Such neurons have been directly observed in primate and other species including birds. In humans, brain activity consistent with that of mirror neurons has been found in the premotor cortex, the supplementary motor area, the primary somatosensory cortex and the inferior parietal cortex."

Considering the impulsing effect of Mirror Neurons for the observer, could all these remotely perceived entertainments be taking advantage of these neurons?

# Answer
> 6 votes
I think it is likely the case. I agree that the idea of a "mirror neuron" is a bit dubious, as it implies that the function of those neurons are related to mirroring. It's probably the case that they represent the actual movement, and their activation in witnessing the action is tangential to that.

As for your question, research was done on this exact topic, with positive results. Mouras et al. found that the magnitude of erection achieved by participants watching erotic videos correlated to the activation of regions known to contain "mirror neurons".

**References** http://www.sciencedirect.com/science/article/pii/S1053811908006897

# Answer
> 6 votes
To use "mirror neurons" explain why people enjoy watching porn is problematic when you consider that people (a least men, Cerny and Janssen, 2011) seem to enjoy watching porn where the actors are solely of the opposite sex. That is, people seem to be enjoying watching porn (or even looking at erotic pictures) when there is nothing really to mirror. As the phenomena of erotic movies is a (evolutionary) quite recent phenomena it makes sense to be aroused when seeing someone have sex as that usually would be a good proxy of that sex was either happening or about to happen.

**References**

Cerny, J., & Janssen, E. (2011). Patterns of sexual arousal in homosexual, bisexual, and heterosexual men. *Archives of Sexual Behavior*, doi:10.1007/s10508-011-9746-0.

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Tags: theory-of-mind
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# Question
Title: How do humans optimize noisy multi-variable functions in experimental settings?
Imagine an experiment like this:

A participant is asked to optimize an unknown function (let's say minimize) . On each trial the participant provides several input values, and receives an output value. Now also imagine that the output is noisy, in that the same inputs lead to an output plus a random component.

To think of but one of many possible specific examples imagine the following function

$$Y = (X -3)^2 + (Z-2)^2 + (W-4)^2 + e,$$

where $e$ is normally distributed, mean = 0, sd = 3.

On each trial, the participant would provide a value for $X$, $Z$, and $W$. And they would obtain a $Y$ value based on this underlying function. Their aim would be to minimise the value of $Y$. They have not been told the underlying functional form. They only know that there is a global minimum and that there is a random component.

I'm interested in reading about the strategies used by humans to do this task in experimental settings. Note I'm not directly interested in how computers do the task or how programmers and mathematicians might complete this task.

### Questions

* What are some good references for learning about the literature on how humans learn to optimize noisy multi-variable functions?
* What are some of the key findings on how humans optimize noisy multi-variable functions?

# Answer
> 6 votes
This is a bit of a tangential answer, but hopefully still useful.

When we give humans noisy data, we can basically think of them as some sort of **Bayesian inference machines** that try to figure out what the function that data came from looks like. The important thing we then need to know, is how strong of a **bias** (prior) humans have towards expecting certain relationships.

Unfortunately, it seems that humans are extremely biased towards positive linear relationships. I think this will make it very hard for them to optimize data presented as in your question, because they will constantly assume it comes from a straight line. This is really well captured by the following figure from Kalish et al. (2007):

The experiment that generated the above picture is rather different from the one you describe, but we can think of it is a very particular type of noise. A person at stage $n$ is given 25 $(x,y)$ pairs from the function at stage $n - 1$. The person is then tested by being given an x value and asked for a y, 25 times. The results of this are passed on to the person at trial $n + 1$ as the training data. Thus, we could think of the errors of person at stage n as noise/errors (although systematic errors) for the person at stage $n + 1$. As you can see, it doesn't take much of this noise to lose all structure of the function you started with and revert to the natural bias of a positive linear relationship. In fact, in condition 1 participants are already completely confused about the U-shaped function after strage $n = 1$ (so the first participant, with no error already has a hard time understanding the function from $(x,y)$ pairs).

### References

Kalish, M. L., Griffiths, T. L., & Lewandowsky, S. (2007). Iterated learning: Intergenerational knowledge transmission reveals inductive biases. Psychonomic Bulletin & Review, 14(M), 288-294. \[pdf\]

# Answer
> 3 votes
This seems related to the literature on **multiple-cue probability learning (MCPL)**. In this paradigm, a typical task presents subjects a list of cues and values, and asks them to predict the probability of certain outcomes. This paradigm has a decent amount of literature both in the JDM (judgment and decision making) community as well as the human factors community. To see the relevance, consider a doctor who has to diagnose a patient (provide treatment) based on a finite set of cues (symptoms).

Empirically, human judgment of this type has been modeled using Egon Brunswik's **probabilistic functionalism**, perhaps more commonly known as the **lens model** or **social judgment theory**. This is a useful methodology for comparing human judgment to true ecological correlations.

The image of above depicts the lens model. To give an example, consider the task of a college admissions board who must decide who to admit. The environment/criterion might be their final college GPA, and cues might be high school GPA, SAT scores, writing sample, etc. You can use multiple regression to find the 'true' ecological weights of these cues on the environment criterion, and similarly you can do the same for the admission board's estimate of a student's success (if they were to estimate GPA).

An admission board will (hopefully) observe the effect of different cues on success, and revise their cue weights with experience. Unfortunately, people are typically not so good at this task.

Some common findings:

* People tend to use no more than 3 cues, even if they claim that they use more.
* People are typically outperformed by a bootstrap model of themselves
* People are often outperformed by a unit weight model of themselves: In other words, if you simply set the highest observed cues weights (on the right hand side) to 1, and all others to 0, you may get a better predictor of outcome.

What I take from this is that people will probably have little chance of success at estimating cue weights from a complex equation such as the one you present. However, you could measure these cue weights iteratively to observe learning rates and do other fun stuff-- even if we are all better off being judged by computer algorithms.

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Tags: experimental-psychology, mathematical-psychology
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# Question
Title: Does language and/or culture affect an individual's cognitive capacity?
Some languages have multiple expressions to identify, address, comprehend, and interpret a single concept and/or experience.

Are limits placed on understanding and describing aspects of cognition due to the finite lexicon being used to explain a mental concept or experience?

Does language create a bottleneck situation where the available lexicon used to define certain aspects of cognition and its experiences are inadequate for understanding the true definition of that experience?

# Answer
This is a hot topic of debate, so my answer will be an incomplete one.

There are actually two separate questions here. One is on language and the other one is on environment.

### Language:

My answer is no; different languages do not limit the conceptual repository of human mind. The current ongoing debate is partially on the Pirahã language. Everett studied this language and after seeing that it does not have syntactic recursion, he claimed that it demonstrates that Pirahã community somehow could not think recursively. Of course this is a very simplified view and may be a little misinterpreted and/or a provocative understanding of the Sapir-Whorf hypothesis. But I believe that the main problem is on the theoretical grounds of grammar. Steedman's CCG shows a very powerful alternative way of looking to grammars. It is computational and combinatorial. I don't know any particular studies on Pirahã with combinatorial grammars, but that would be an interesting issue to investigate. My personal opinion is that this thinking of "language effects the way of thinking" is also a bit dangerous and open to manipulations too much.

### Environment:

Environment definitely affects the cognitive abilities. There are several studies on this. You can search the internet for papers such as Gathercole (1999) or Gleitman, Elissa, Newport (1995). These are the ones that came to my mind immediately. One of the facts is that late exposure to language entirely limits the grammatical abilities. Environmental feedback is also essential. It may be hard to observe physically impaired children but there are also studies that focus on deaf children in hearing families in the absence of sign language. These are interesting studies, but the bottom line is: yes, environment affects cognitive abilities.
> 20 votes

# Answer
I'm not sure what you mean by cognitive capacity, but I absolutely believe that language shapes the way we think. The collective nouns, verbs, and phrases of a language are the categories by which a culture interprets things.

Consider seizures. Our culture may call them seizures, and a doctor might posit that their cause is epilepsy (or something). That's how we would approach understanding the phenomena. In another culture, they could say that the person is possessed, and they might posit that they cause was an evil spirit. That's their understanding of the phenomena. It might be easy to dismiss that, but if you think about it you'll see that most of us only understand epilepsy as much as they might understand how the spirits work. It's just a word used to explain something. Even the word epilepsy itself, actually means to be taken upon and seized. In it's original usage it was implied that some otherworldly force was doing the seizing. Can you imagine if the other culture I invented had created modern science? Surely their terminology would revolve around the term for "seized by an evil spirit".

Or consider something as basic as color perception. To us, it feels absolute and more an attribute of external reality than anything internal. But even how we understand color is variable with language. Heinrich (1972) looked at the Eakimo and found that the way they categorize color was significantly different from ours, and follow language lines.

Another reason why I think that yes, language defines understanding, is seen in modern science. Modern science is almost *defined* by the rapid and dizzying creation of new language. As we build a finer grained understanding of things, new terms need to be created to even understand the topic, let alone discuss it. Consider Organic chemistry, where a virtual new language has even been created to describe molecules.

The last point I have to make is that *there is always another distinction to be made*. We haven't gotten to the bottom of anything yet, and I don't suspect we will for a long time if ever. Our words are categories, which means they contain multiple things that are similar to some degree. House is a broad word, a large category. Mansion, hovel, etc... are more narrow words, less inclusive categories. And so on. How fine a category could we make to describe homes? Theoretically we could have a word that perfectly describes each individual house.

The words available to us define how we can think of and communicate things. Different cultures have different words available to them, and thus think of things differently. I had a very interesting conversation with a Catalan friend about words in that language that have no correlate in English. it was very enlightening.

**References**

http://www.npr.org/2011/09/30/140954025/science-diction-the-origin-of-the-word-epilepsy

http://www.jstor.org/pss/30029324
> 3 votes

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Tags: intelligence, language, theory-of-mind, philosophy-of-mind
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title: How do humans control saccades?

text:
# Question
Title: How do humans control saccades?
I've gathered the standard rational for a visual system utilizing saccades from perception textbooks: the neural cost of processing an entire scene at a high level of detail would be prohibitive, but low-fidelity images aren't good enough to function in the world. Thus you have an retina with a high-fidelity center which can sample the scene by saccading around, presumably guided by a combination of information about the low-fidelity surround and the beliefs and goals of the perceiver.

However, I've yet to find a detailed theory that answers the question of **how the next saccade target selected.**

To clarify, by 'detailed theory', I mean a theory that describes the **mechanisms** used to accomplish the computational feats described in the standard textbook explanation I mentioned above.

# Answer
Treisman & Gelade's Feature Integration Theory suggests that we are able to process an entire visual scene in parallel at the level of individual features. For example, in a visual search task, the time required to find a blue circle in a field of red circles is *independent of the total number of circles*. However, focused attention (typically foveal) is required to integrate independent features into a cohesive object. Thus, if searching for a red circle in a field of blue circles and red squares, search time grows linearly with the number of total objects. This is because the target is made up of two features (circle and red) which need to be integrated in order to be identified-- requiring saccades around the scene.

Several theories of visual search use this distinction to model visual attention shifts. Most notably, Jeremy Wolfe's Guided Search and Itti & Koch's visual attention model. The basic premise behind both models is somewhat similar: low level feature receptors respond automatically and in parallel to the entire visual field. Thus, there are many individual feature maps that represent *bottom-up saliency* of locations in the visual scene. This bottom-up saliency can be sufficient to trigger a saccade; for instance, a feature map that responds to local motion is beneficial for an organism to identify moving predators. Thus, areas with motion are given high value because they have a history of providing information that is beneficial to an organism.

During task conditions (such as visual search), *top-down saliency* maps may also be created based on knowledge of what things in the environment have value. If I am searching for my umbrella, I know that it is blue and long and straight, and this information can be encoded in the feature maps that drive saccades.

More generally, saccades are directed at targets that have a high expected value. (It has even been shown that the velocity of saccades is proportional to the expected value of the target: Shadmehr, et al.) This value is determined from a weighted evaluation of both top-down and bottom-up feature maps, available pre-attentively.

The *exact* location of a saccade is determined through a process called spatial pooling, which attempts to determine the 'center of gravity' of a target, again using low level feature maps. While saccades are amazingly quick and accurate, there is of course some error in final saccadic position which often require smaller saccades to reach the target. It has recently been suggested that this series of saccadic movements emulate Fitts' law with regards to speed-accuracy tradeoffs. A great, thorough review of the current state of saccadic eye movements can be found in Kowler, 2011.

There is obviously quite a bit of detailed information that I haven't covered here-- out of the references cited, I would start with section 3 ("Saccades") of the Kowler article, then move on to the Itti & Koch article for more concrete details on their specific model.

> Wolfe, J.M. (1994). Guided Search 2.0. A revised model of visual search. Psychonomic Bulletin & Review, 1, 202-238.
>
> Itti, L., & Koch, C. (2001). Computational modelling of visual attention. Nature Reviews Neuroscience, 2, 1-11.
>
> Shadmehr et al. (2010). Temporal discounting of reward and the cost of time in motor control. Journal of Neuroscience, 30, 10507-10516.
>
> Kowler, E. (2011). Eye movements: The past 25 years. Vision Research, 51, 1457-1483.

\** Note I cite Guided Search 2.0 because it is a good exposition of the whole theory, though the theory itself has progressed to 4.0
> 16 votes

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Tags: computational-modeling, perception, vision, eye-movement
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# Question
Title: Any attempts at testing or modeling the 'cognitive conception' of language?
For those unfamiliar, the 'cognitive conception of language' refers to a claim made by some theorists that, in the words of Carruthers:

> "besides its obvious communicative functions, language also has a direct role to play in normal human cognition (in thinking and reasoning)."

I've found such accounts extremely intriguing, especially that of Daniel Dennett (1994), who basically claims that language is what turns our massively parallel brain into a decent serial processor.

However, I'm distressed that such discussions are generally tethered to the Philosophy of Mind and despite my efforts, I've yet to come across any empirical evidence or cognitive models that are for or against such hypotheses.

So, do such studies exist (or are underway)? Or is there something fundamental to this subject that keeps it only in the realm of armchair discussion?

### References

# Answer
> 4 votes
There's a quite active line of research (and debate) in experimental psychology and cognitive science on this. It often goes under the rubric of the "Sapir-Whorf hypothesis". I only know some of the work in this domain, but I would suggesting checking out research (experiments, not just armchair discussion) by Lera Boroditsky and Gary Lupyan.

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Tags: cognitive-psychology, cognitive-modeling, language, philosophy-of-mind
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# Question
Title: When is higher confidence predictive of less accuracy?
Normally, when an individual is more confident in a particular response (e.g., memory decision, general knowledge answer), he or she is also more likely to be accurate. There are also studies in which higher confidence is generally demonstrated to be unassociated with higher accuracy.

Are there any studies which demonstrate that the more confident an individual is, on average, the more likely he or she is to be *incorrect*?

# Answer
> 7 votes
This may not answer your question directly, but is related:

Kruger and Dunning (1999) conducted a study in which people performed a variety of 'tests' in different domains, such as logical reasoning, grammar, and humor. After taking a test, participants were asked to judge their performance relative to other test-takers, and to estimate their objective score on the test (how many questions were answered correctly).

What they found was that the subjects who performed the *worst* actually overestimated their performance the *most*. If you take their performance estimate as a proxy for confidence, then it supports your hypothesis-- but only to a relative degree. That is to say, participants who performed poorly did not estimate their ability to be better than good performers and vice versa; however, those who performed the worst were more confident in their ability. It's a bit confusing, and D&K can explain it better-- there's actually a paragraph in their article (second to last) which relates their findings to work on overconfidence.

The explanation that Kruger and Dunning give for this effect is that the metacognitive ability to assess one's performance is a correlated with actual performance on the same task. Thus, somewhat paradoxically, those who perform poorly may be unaware of their poor performance, due to their inability to predict how well they did.

> Kruger, J., & Dunning, D. (1999). Unskilled and unaware of it: How difficulties in recognizing one's own incompetence lead to inflated self-assessments. *Journal of Personality and Social Psychology*, 77, 1121-1134.

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Tags: cognitive-psychology, memory, decision-making, confidence
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# Question
Title: Are spaced flashcards effective for learning?
Several apps and sites offer flashcard-based learning that repeat the cards you do poorly on over a period of time (the more inaccurate the answer the closer to each other the repetitions are). One example of this is Super Memo.

* Is there rigorous empirical support for these types of flashcard systems working?
* Do they exploit a known function of memory?

# Answer
There's lots of research out there on flash cards and they are a proven, effective study aid.

Flash Cards work because of the "Forgetting Curve"; rehearsal and retrieval before you forget an item strengthens the memory before it decays allowing one to optimize encoding into LTM.

The paper Optimising learning using flashcards: Spacing is more effective than cramming is a good summary of why Spacing helps retention, highlighting why it's effective in education and should be emphasized over cramming, which current educational models (finals, tests) currently promote.

Spacing is effective for **Long Term Memory** as opposed to cramming/massing which is only effective (but it IS effective) in the short term as shown by the above forgetting function.
> 19 votes

# Answer
Flash cards work for two main reasons:

1. they serve as retrieval practice
2. they force the student to space practice out

Both of these reasons have been demonstrated to enhance learning.

Retrieval practice, sometimes called the *testing effect*, has been shown by Roediger and colleagues to promote learning above and beyond additional study. For instance, in a 2006 study by Roediger and Karpicke, some subjects studied material several times then took a test (SSST, where S = study and T = test), whereas other subjects studied material less then took a several tests (STTT). After a brief delay, memory was shown to be better for those who had self-tested relative to those who hadn't. In a 2007 study by Karpicke and Roediger that actually used flash cards, the memorial benefit was always greater when individuals self-tested rather than merely restudied -- and importantly, best when individuals continued to self-test even when they thought they had the information down cold. This suggests that you shouldn't "drop out" flash cards from the deck if you get them right once or twice. Another 2006 Roediger and Karpicke paper provides additional evidence in more applied contexts.

The spacing effect is also a powerful influence, here, as well. Research by Bjork and colleagues on a parsimonious (yet slightly circular) idea called *desirable difficulties* provides one theoretical example for why this is so. Learning is most powerful when it is most difficult, and spacing out your study (or, as above, your test) provides that information with time to decay (or be interfered with by other memories) such that when retrieval is successful, it is rather potent. Note that one concern with spacing is that if study is pushed too far out, successful retrieval cannot occur, leading to no benefit to memory.
> 15 votes

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Tags: learning, memory, mnemonic, encoding
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# Question
Title: Is there a complete cortico-cortical connectivity map based on a useful partitioning of the cortex?
I have something like Brodmann Areas in mind, but any complete list of cortex regions would do. I'm primarily interested in human brains here. Ultimately I'd like enough information to be able to build an NxN matrix containing boolean "innervates" entries. Numbers representing an "innervation strength" would be great too.

# Answer
> 6 votes
Yes-- you may be very interested in the Human Connectome Project (also here), whose goal is to map human brain connectivity.

One of the primary tools used to map functional and anatomical connections is diffusion tensor imaging (DTI). Unlike the more often used T2-weighted images, DTI allows researchers to image white matter tracts directly.

The data from the HCP is available for free to researchers, but you need to apply for access. See their website for details.

# Answer
> 4 votes
You might be very interested in a paper by Felleman and Van Essen (1991). In the paper, they analyze the connections between many cortical areas, and create a database to store the connection values. They also have some interesting things to say about hierarchical connections and cortical layers.

**References**

http://cercor.oxfordjournals.org/content/1/1/1.1.abstract

# Answer
> 1 votes
Currently, no such high-level maps based *directly* on human cortex exist (as far as I can tell). The closest model organism for which high-level maps exist is the **macaque**:

* In 1991, Felleman & Van Essen published the first extensive analysis, which includes a noteworthy connection diagram (see p. 30).
* In 2010, IBM (Modha & Singh) published what appears to be a complete set of connection diagrams.

### References

> * Felleman, D.J. & Van Essen, D.C. (1991) Distributed Hierarchical Processing in the Primate Cerebral Cortex. Cerebral Cortex 1:1-47. \[pdf\]
> * Modha, D.S. & Singh, R. (2010) Network architecture of the long-distance pathways in the macaque brain. PNAS 107:13485-13490. \[pdf\] \[supplemental pdf\]

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Tags: neuroscience, computational-modeling
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# Question
Title: What is a validated single-item measure of mood?
Has anyone validated, proposed or tested a single-item state-based positive affect or happiness measure? I am particularly interested in something for tracking mood every day.

# Answer
> 18 votes
Many single item measures of mood can be found in the literature. Those two are based on the idea that affect is bidimensional and that one's current state can be reported using a grid:

* Russell, J.A., Weiss, A., & Mendelsohn, G.A. (1989). Affect Grid: A Single-Item Scale of Pleasure and Arousal. Journal of Personality and Social Psychology, 57 (3), 493-502.
* Larsen, J.T., Norris, C.J., McGraw, A.P., Hawkley, L.C., & Cacioppo, J.T. (2009). The evaluative space grid: A single-item measure of positivity and negativity. Cognition and Emotion, 23 (3), 453-480.

You might also want to look at http://studiolab.ide.tudelft.nl/studiolab/pmri/ \[Disclaimer: I know the people who developed it\]. It is conceptually similar to Russell's AffectGrid but purely non-verbal.

Finally, it seems necessary to mention the Self-Assessment Manikin. Technically, it's not a single-item instrument (the original version has three, many people use only the first two) but it is very popular. Main publication is Bradley, M.M., & Lang, P.J. (1994). Measuring emotion: The self-assessment manikin and the semantic differential. Journal of Behavior Therapy and Experimental Psychiatry, 25 (1), 49-59.

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Edited (a long time) after comment: Most authors in this field argue that mood or affect are fundamentally bi-dimensional, if not more, so it makes sense that measures would also be bi-dimensional. The closest you can come to a single Likert-type item would perhaps be the SAM valence scale.

Another issue is that traditional psychometrics is almost entirely focused on dealing with item-specific variance, i.e. how to select items to build a scale, how many items are needed to reach a given level of reliability, how to model latent constructs using different items, how to equate scales or build population norms, how to adapt scales to different populations, etc. There is not much you can do with single items.

Consequently, it's not very complicated to create a new “valence measure” by drawing some smiling faces, altering the response format or slightly changing the wording. If the new measure is not completely idiosyncratic, you will obtain some level of correlation with other valence measures but beyond that what could make it a “valid” or superior measure of mood?

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Tags: io-psychology, emotion, test, well-being
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# Question
Title: What is the relationship between language and the level of comprehension of consciousness?
I asked a similar/related question a couple days ago about how language and/or culture affect an individual's cognitive capacity.

I'm looking for materials, if any, on the subject of a language's relationship with the level of comprehension of consciousness.

For example, if a specific language doesn't have the right words to describe the biological aspects of visual perception, will the individual using that language be able to comprehend all aspects of consciousness as well as an individual using a language which has the words to describe the event?

I've read The Rediscovery of the Mind by John Searle and it discusses some issues of how our current state of understanding consciousness is a function of the scientific progressions of society. He talks about how we could be misunderstanding/misinterpreting the fundamentals of consciousness when we use out-dated and/or inaccurate definitions & concepts as a scaffold for defining current theories of consciousness.

Are there any books, studies, theories, or relevant materials on this topic?

# Answer
> 7 votes
One thing that comes to mind is the discussion over why English-speaking people think submarines cannot swim, while they think airplanes can fly. Supposedly in Russian, though, they do refer to submarines as "swimming."

Meanwhile, we ask whether computers can think, without really realizing that this question turns out to be simply a question about semantics, just like the question of whether or not a submarine can swim.

(Edsger Dijkstra said: "The question of whether a computer can think is no more interesting than the question of whether a submarine can swim.")

The thing is, some words we use we consider, by definition, apply only to humans or animals. We seem to be more concerned about the pedigree of the thing, than its actual behavior or function.

We use the word "conscious" similar to the word "swim"....it, almost by definition, only applies to living things. On the other hand, the word "aware" is much more commonly used to refer to something a machine or object might be capable of. For instance, a thermostat is "aware" of the current temperature in the room, or my computer is "aware" of the other computers on the network. There is a very real thing we are describing about the thermostat and the computer, and we aren't being metaphorical. (note that the computer is even aware that one of those computers on the network is actually itself. Is is therefore "self aware"?)

People use lots of words in everyday speech that fall into this grey area of metaphor or anthropomorphism. We say a magnet is "attracted" to metal, without it feeling like we are anthropomorphizing or speaking metaphorically...we just define "attract" in a way that can apply to both objects, animals and humans.

Likewise, people instantly understand what we mean if we say the magnet "wants" to stick to the metal, or that a magnet "doesn't like" having its north pole pressed against the north pole of another magnet... but, if you ask them, they might say we are being poetic in our speech by applying those terms to a simple object like a magnet.

As time goes on, more and more words that formerly applied to only people or animals, will start being used to describe things going on in machines. A cameras "sees". A security system "notices" a person moving in the room. A computer "makes a decision". A thermostat "tries" to get the temperature in the room to match the one set on its dial. Siri "understands" what I said. My Tivo "thinks" I will like a show. Obviously these aren't just changes in the definitions of words, they go hand in hand with advances in technology that results in our having occasions to meaningfully use the words to apply to non-living things.

So, to get to the point, yes, I think the language we use absolutely affects comprehension of consciousness. The more we get comfortable using the word "conscious" (and all these other words, "think," "aware," "try," "like," "want," "decide," "detect") to refer to things a machine is capable of, the less we will see the concept of consciousness as being mysterious and magical. I think that the "hard problem" of consciousness will not be "solved" by science, instead, science, technology, and the evolving way we use language to describe machines will gradually make the problem seem non-existant.

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Tags: learning, language, terminology, consciousness, theory-of-mind
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