What do within-subjects studies of job applicant personality test faking say about the covariance between developmental and job applicant scores? Some studies of faking personality tests in selection and recruitment have used a within-subject design. These studies involve administering a personality test in two conditions. One condition is assumed to measure honest responses (e.g., under honest instructions in the lab or for professional development purposes in an applied setting). A second condition is designed to elicit an authentic job applicant responses (e.g., role play instructions in the lab or a real-world job application in applied settings).

What has such research found regarding the structure of the covariance between scores in developmental and applicant conditions? I.e., what is the size of the correlation and what is the shape of the bivariate distribution (I think that bivariate normal is unlikely)?
What is known about the distribution of difference scores (i.e., applicant minus developmental)?

I'd also be interested in learning how findings vary based on features of the test,  context,  design, and so on.

Richard Griffith and Patrick Converse (2012) provide a good review of    personality faking research that has employed a within-subjects design to examine changes in responses to personality tests between an applicant and a development context.

The following represent my review of the papers identified by Griffith and Converse (2012). I take it as fairly well established in the literature that most, but not all, studies find differences in group means between between different applicant and non-applicant conditions. This review focusses on individual differences in whether people fake and the amount of faking.

Arthur et al (2010)

Among other things, Arthur et al (2010) reported two studies that looked at differences in responding between participants completing a personality test as job applicant and then around a year later completing the same personality test as an anonymous research participant.

SEM_d: The authors used the standard error of test-retest measurement $\text{SEM}_d$ to classify in an operationalised way whether a participant had engaged in response distortion in the high-stakes context

$\text{SEM}_d \lt 1$ indicated lower score at time 2 (i.e., faking)
$\text{SEM}_d \gt 1$ indicated higher score
$|\text{SEM}_d| \lt 1$ indicated unchanged score (i.e., honest)

Results in study 1 suggested that for most personality scales a little over 30% of scores were classified as lower in the low stakes condition.

Of course this value should be interpreted in light of the fact that based on the normal distribution and the chosen cut-offs, one would expect around 16% above this cut-off. There are also issues of regression to the mean, and reduced reliability in the extremes that could be considered in a more sophisticated analysis. Finally, this indicator of faking does not provide information on the distribution of faking scores.

SEM_d by job applicant score:
They also explore the prevalence of score reduction relative to scores in the high stakes condition. They conclude that prevalence of score reduction does not vary with High stakes scores. However, the graphs are a little difficult to interpret (being stacked bar charts). Also, by design the graphs answer the question of what proportion of test takers at a given level are faking, which is interesting , but they don't answer the question of whether true score is related to faking.

Correlation between applicant and research context scores:
Table 5 reports $\text{time}_1 - \text{time}_2$ correlations for both studies for the Big 5. Correlations are between .49 and .78.
Such correlations make sense in light of the idea that some participants are answering honestly and others are faking. This should produce correlations a little lower than typical test-retest reliabilities.

Of course, many factors influence correlations of personality test scores in applicant and research contexts. In particular, reliability of the test and time between tests would be important. Thus, it's a little difficult to say how much of the observed reduction in the correlation is due to faking in the applicant context, and how much is due to other factors.

The researchers do provide an $n=44$ sample of participants in Study 1 who completed both conditions in low stakes contexts (i.e., existing employee and research contexts). These correlations are reported in Table 6. The following analysis using R shows the correlations for the two conditions, where theory would suggest that the High Stakes-Low Stakes (i.e., HL) condition should have smaller correlations, although the observed difference is fairly minimal.

x <- data.frame(matrix(c(0.53, 0.55, 0.51, 0.7, 0.66, 0.56, 0.49,
    0.5, 0.87, 0.75), ncol = 2))
names(x) <- c("HL", "LL")
row.names(x) <- c("Agreeableness", "Conscientiousness", "Emotional stability",
    "Extraversion", "Openness")
x$diff <- x$HL - x$LL
round(rbind(x, Mean = sapply(x, mean)), 2)
##                       HL   LL  diff
## Agreeableness       0.53 0.56 -0.03
## Conscientiousness   0.55 0.49  0.06
## Emotional stability 0.51 0.50  0.01
## Extraversion        0.70 0.87 -0.17
## Openness            0.66 0.75 -0.09
## Mean                0.59 0.63 -0.04

Griffith et al (2007)

Griffith et al (2007) conducted a study where 60 applicants completed a 30-item measure of conscientiousness first in a job applicant setting. Then one month later, they completed the test under instructions to answer the test honestly and to fake.

They found a correlation between honest and applicant of $r =.50$, and a standardised difference between honest and applicant of $d = 61$.
This shows that scores are increasing in applicant settings, and that there are individual differences in the extent to which this occurs. Although the absence of knowledge of the test-retest correlation in an honest-honest context makes it a little difficult to assess the degree to which this correlation is less than would be expected.

They also employed several indices to act as difference score thresholds, which classified 31 or 22 percent of applicants as faking depending on the index.

In a latter part of the paper there is also some discussion of variation in the size of the difference score.

Ellingson et al (2007):

Ellinson et al performed a study based on a large database of participants who had completed a personality test under the four combinations of development and selection contexts.

Average Development-development sample correlations were $.66$ were a little bit higher than average development-selection ($r=.62$) and selection-development ($r=.57$) correlations.

Average increases from session 1 to 2 suggested somewhat low levels of response distortion.

                           average scale d
development/development     0.14
development/selection       0.26
selection/development       0.04
selection/development       0.07

As far as I can tell, there was no specific discussion of the distribution of change scores.

Others

Donovan et al (2008) and Peterson et al (2008) sound interesting, but they are conference presentations so the publications are not readily available.

Summary

Thus, in summary, there is some evidence that the correlation is lower between applicant and development conditions than it would between two comparable development conditions.
Presumably the size of this drop in correlation is related to the amount of faking, and that the amount of faking is related to the amount of individual differences in faking.

There is certainly a qualitative awareness of there being different categories of  faking.
Ellingson write:

  Conservative estimates from this line of research suggest that
  less than 20% of applicants intentionally distort their responses
  and that less than 4% of applicants do so to an extreme degree

However, I haven't yet read much from these within-subject studies about the distribution of faking scores, nor have I seen formal mathematical models of the change scores, even though the data would permit such analyses.

References

Arthur, W., Jr., Glaze, R. M., Villado, A. J., & Taylor, J. E. (2010). The magnitude and extent of cheating and response distortion effects on unproctored Internet based test of cognitive ability and personality. International Journal for Selection and Assessment, 18, 1-16. PDF
Donovan, J. J., Dwight, S. A., & Schneider D. (2008). Faking in the real world: Evidence from a field study. In R. L. Griffith & M. H. Peterson (Chairs), Examining faking using within-subjects designs and applicant data. Symposium conducted at the 23rd Annual Conference for the Society for Industrial and Organisational Psyhcology, San Francisco, CA.
Ellingson, J. E., Sackett, P. R., & Connelly, B. S. (2007). Personality assessment across selection and development contexts:  Insights into response distortion. Journal of Applied Psychology, 92, 386-395.
Griffith, R. L. & Converse, P. D. (2012). The rules of evidence and the prevalence of applicant faking in New Perspectives on Faking in Personality Assessment, Chapter 3, 34-52.
Griffith, R. L., Chmielowski, R., & Yoshita, Y. (2007). Do applicants fake? An examination of the frequency of applicant faking behavior. Personnel Review, 36, 341-355. PDF
Peterson, M. P. Griffith, R. L., O'Connel, M. S., & Isaacson, J. A. (2008). Examining faking in real job applicants: A with-subjects investigation of score changes across applicant and research settings. Paper presented at the 23rd annual meeting for the Society for Industrial and Organizational Psychology, San Francisco, California.


How to find the upper and lower quartiles of the Ryff scale? I received this question via email and thought the answer might be sufficiently general to be worth posting here.

  I have used the Ryff
  scale  in my research
  . Actually I am confused about the scoring. The
  minimum possible  score  is 54 and the maximum score 324. I calculated
  this after reversing the negatively worded items. The author of the
  scale mailed me saying the scale has no cut-off points score you have
  to consider the upper 25% as higher level of psychological well-being
  and the scores in the lower 25% as poor psychological well-being.

  How would I find the upper and lower  25% (I guess called as Quartile)
  from just the minimum and maximum score on the scale?

Obtaining the quartiles:
Typically you obtain quartiles from the data. Thus, you would have sample data (either your dataset or another dataset), and you can use software to give you .25 and .75 percentiles (or alternatively, you can get such values fairly straightforwardly by rank ordering the data).

Of course, you might be referring to a slightly different notion to quartiles. You might be thinking about low and high scores relative to the scale range. So for example, the mid point of 1 to 5 scale is 3. Therefore, you could say that a mean below 3 suggests that people are below the midpoint on a  scale.
This idea can readily be extended to other percentiles of the scale range.

The basic equation could be expressed as follows:

min + percentile * (max - min)

where min is the scale minimum and max is the scale maximum and percentile is the percentile of interest (e.g., .25 and .75 in your case or say .5 for the midpoint).

Applying this you get

54 + .25 * (324 - 54) = 121.5
54 + .75 * (324-54) = 256.5

for your low and high cutoffs.

Of course, there's all sorts of discussion you could have about whether this whole process is reasonable, and in general you should try to use the continuous scale for your analyses.


Why do people have different personalities when speaking different languages? Edit: This study is much more relevant in terms of the question.

This study suggests (according to article linked below) that a multilingual person can have multiple personalities, each tied to one of the languages that he or she speaks.

Here's an article about the study.

One personality may be active when the person is interacting in one language, another when interacting in another language, etc.

I have seen this phenomena very distinctly in myself.

Why does this happen?

This is a typical example of the misrepresentation of scientific reseach in popular media.

The orignal study concludes that "language effects on cognition are context-bound and transient, revealing unprecedented levels of malleability in human cognition". The word "personality" does not appear in the original paper. Nevertheless the Daily Mail comes to the conclusion that "[s]peaking two languages really could give you a split personality, researchers have found". No, they haven't.

To understand what is going on here, I recommend the following video to you:

https://www.facebook.com/LastWeekTonight/videos/896755337120143/

So what does the study find? It finds that the different grammatical structures of different languages can influence how people perceive the world and process information. (Please note the word "can" here! It does not always happen, and only to a small extent.) This is an old hat and called the Sapir-Whorf hypothesis.

As for how this changes the "personality" of multilingual speakers: It doesn't. It changes the information that the speakers use to assess the situation and plan their behavior.


Is teacher guidance always necessary to become an expert? Is it necessary to have a teacher (or mentor/coach) to master every skill? What if I am taking an online tutorial with pre-recorded videos? Can I count that teacher training?

I have read the concept of deliberate practice and 10,000 hours of practice being needed to become an expert. But my question is whether these 10,000 hours need to be (partially) guided to receive personal feedback and/or coaching, or whether self-learning is sufficient?

I'll give you an example of a famous mathematician who developed his mathematical research in isolation. Arguably If someone manages to achieve a high level of skill in solitude for such an extraordinary difficult discipline as mathematics I would deny the need to have a teacher (in any case) to master a skill which is less difficult than be an expert in math. (Which is arguably any discipline). However as mentioned in the comments having some kind of feedback might be useful in mastering a skill faster. Additionally not every person is as gifted as was S. Ramanujan. Therefore I suggest it depends on your inborn intellectual abilities with regard to the skill you want to become an expert of. Therefore this question cannot be answered in general but only with respect to person X inborn intellectual qualities with regard to the skill person X wants to become an expert of.
http://en.wikipedia.org/wiki/Srinivasa_Ramanujan


Is perfectionism related to OCD? Is it right to say that a really strong attitude and stubbornness to do something is really similar to an obsession?

I'll try to explain better what I mean.

Let's take a really good developer or a really good scientist. Very often the reason which is leading him to be so good is the addiction to his work.

For some guys, for example, the respect for the rule should be maniacal.

So, is it possible to state that a strong perfectionism / addiction is often readable as a form of obsessive personality trait? (maybe ego-syntonic, and since not a disorder)

Perhaps check out the Obsessive Beliefs Questionnaire which is designed to measures dysfunctional beliefs related to OCD. There are several papers that examine the factor structure, and perfectionism is typically seen as one of the major aspects of obsessive beliefs.

However, it seems to be a particular form of maladaptive perfectionism. See these perfectionism items from the OBQ:

  In order to be a worthwhile person, I must be perfect at everything I do
  If I can’t do something perfectly, I shouldn’t do it at all
  Even minor mistakes mean a job is not complete
  For me, things are not right if they are not perfect
  For me, making a mistake is as bad as failing completely.
  I must keep working until it’s done exactly right.

Thus, this is more than just doing your best to achieve good outcomes.

References

Moulding, R., Anglim, J., Nedeljkovic, M., Doron, G., Kyrios, M., & Ayalon, A. (2011). The Obsessive Beliefs Questionnaire (OBQ):Examination in non-clinical samples and development of a short version. Assessment, 18, 357-374.
Myers, S. G., Fisher, P. L., & Wells, A. (2008). Belief domains
of the Obsessive Beliefs Questionnaire-44 (OBQ-44) and their
specific relationship with obsessive-compulsive symptoms.
Journal of Anxiety Disorders, 22, 475-484.
Obsessive Compulsive Cognitions Working Group. (2001). Development and initial validation of the obsessive beliefs questionnaire and the interpretation of intrusions inventory. Behaviour Research and Therapy, 39, 987-1006.
Obsessive Compulsive Cognitions Working Group. (2005). Psy- chometric validation of the obsessive belief questionnaire and interpretation of intrusions inventory—Part 2: Factor analyses and testing of a brief version. Behaviour Research and Ther- apy, 43, 5127-1542.


What is the relationship between rejection sensitive dysphoria and ADHD? I discovered something called Rejection Sensitive Dysphoria (RSD). If you google it, the first page will show pages that talk about it in relation to ADHD.

What is it about ADHD that causes "nearly everyone with" it to have RSD?

Someone might say that ADHD people would not be sensitive to rejection because they have too many thoughts unless they're hyperfocused on such rejection.

RSD sounds like something related to anxiety rather than attention deficiency or hyperactivity. So someone may suspect that RSD belongs to people with anxiety, depression, bipolar or people with a personality disorder like borderline or narcissistic rather than to people with ADHD. I really can't think of a connection between RSD and ADHD.

Upon closer examination, it appears that Rejection Sensitive Dysphoria is a term that was coined by Dr. William Dodson to describe the phenomenon of rejection sensitivity in ADHD sufferers. It does not appear to be a 'valid' term, in the sense that there is no DSM definition. In fact, it seems that Dodson himself is the only one to have used the term. Dodson specializes in adult ADHD, and so it makes sense that the only articles associated with the term would pertain to ADHD.

As for the phenomenon of rejection sensitivity itself, note the definition of dysphoria as follows: "a state of feeling unwell or unhappy; a feeling of emotional and mental discomfort as a symptom of discontentment, restlessness, dissatisfaction, malaise, depression, anxiety or indifference."

In a broader sense, these are issues associated with chemical imbalances -- as is ADHD. One could even describe ADHD as its own dysphoria. It is also quite common for other disorders to coexist alongside ADHD, particularly anxiety, depression, obsessive-compulsive disorder and bipolar disorder. This -- coupled with the fact that children with ADHD often find themselves socially isolated -- may be responsible for a higher prevalence of rejection sensitivity in those with the disorder.

The following is an edit by the OP, Jack Bauer.

Dodson likely did not coin the term RSD, but he might have been the first to use it with ADHD. It has been used in relation to borderline people: 1 2 3 4 5


Do gating mechanisms in the neocortex have individual degrees for all gated connections? For example, the upward connection between layers in the neocortex flows through the thalamus which is assumed to have a gating function.

I wonder whether there is a single value per gate, determining the degree to which patterns can pass. Or can the gate be different for different synapses or signals at the same time? In this case, there would be more like a vector of degrees for all individual synapses of the gated nerve cord.

Is there anything known about this?

A paper just came out last week in Neuron demonstrating dendrite-specific gating:
http://www.cell.com/neuron/fulltext/S0896-6273(16)00054-4?elsca1=etoc&elsca2=email&elsca3=0896-6273_20160302_89_5_&elsca4=Cell%20Press
Structured Dendritic Inhibition Supports Branch-Selective Integration in CA1 Pyramidal Cells
Erik B. Bloss, Mark S. Cembrowski, Bill Karsh, Jennifer Colonell, Richard D. Fetter, Nelson Spruston
DOI: http://dx.doi.org/10.1016/j.neuron.2016.01.029


How can consumers  obtain an image and analysis of their own brain? What resources are there for consumers who wish to get a detailed analysis of their personal brain function?  (besides consumer EEG machines...)

That is, how do I get access to an fMRI scan?  What's the current price range for such a thing?  Do I have to be a grad student/researcher?

Furthermore, how do I get a detailed analysis of anything that could be interesting/out of the ordinary?

The easiest way to get an fMRI (and many other brain) scan is to volunteer to be a participant at your local university, hospital, or research center. They will let you keep a picture of your brain, provide some interesting information at de-briefing, and usually even give a bit of monetary compensation for your time. Since the research group has to have an MD on board in order to do these tests, they will also notify you if they detect something abnormal or dangerous in your scan. The only caveat is that the selection criteria for being a participant are usually a little bit more involved than in a standard psychological study. Thus, you might have to volunteer for a few studies before you are selected.

If you want further analysis, you might consider companies like this. There you can submit your brainscans after you've received them for further analysis.


Why is it so difficult to use a "true mirror" as a mirror This Youtube video shows what a "true mirror" is: https://www.youtube.com/watch?v=ZSxCZCy5Wsk

In short, when you look into a true mirror you look at yourself (among other things) as you really are, instead of as a mirror image. That is what looking at real time video recording feels like.

But as anyone ever tried shaving or doing their makeup using a live video can tell, a true mirror makes you clumsy, to say the least. From my own experience, I find myself constantly confuse both left-right and front-back in such a case, which is interesting because a true image is just a mirror image that reverses left-right and front-back. So it seems to me some part of my brain in some sense recognizes my true image as a mirror image, and summons whatever pertinent mirror image circuits to automatically take on from there. Any other thoughts on how to explain this difficulty?

Think about this: suppose a person grows up never seeing a mirror reflection, will he be able to use a mirror for the first time? will he not be better off with a "true mirror" than with a mirror? If he grows up using true mirrors, will he be as clumsy with mirrors as we are with true mirrors? We feel natural and at ease dealing with mirror images. Is this just the result of practice and experience? I'm curious if a true mirror will become as natural as a mirror if one uses it for long enough.

This answer supports the comment by Krysta that we are simply used to the mirrors we have and could just as easily learn to use a "true mirror".

In 1950, Theodor Erismann and Ivo Kohler performed a famous self-experiment in Innsbruck, Austria. Kohler wore a pair of glasses that turned his view of the world upside down continually for 124 days (sic). After about 8 days his perception had adapted and he was able to ride a bike or paint just like before.

The image below shows Kohler wearing the glasses:

Here is the original documentary movie created by the two researchers (in German) on the website of the Center for the History of Psychology at the University of Würzburg, Germany: http://www.awz.uni-wuerzburg.de/archiv/film_foto_tonarchiv/filmdokumente/th_erismann_ikohler/die_umkehrbrille_und_das_aufrechte_sehen/

Here is an article from the German Wikipedia describing the glasses and showing an image of a current (self-built) model: http://de.wikipedia.org/wiki/Umkehrbrille I don't know what this "Umkehrbrille" ("turn around glasses") are called in English.


How to tell a diagnosis from an actual state? Since diagnoses merely represent what a doctor is thinking, how can a mental patient know the difference between de facto "reality" and what decisions a doctor is planning?

We know planning is not real but a mental patient can't say that a decision from a doctor is not reality, even though a decision from a doctor is not anything that has a physical existence.

So if the doctor decides a 5150 or likewise, I'm not asking about the legal processes but how you could convince that a diagnosis is not just a model.

What is a mutual indicator for every sz or psychosis? IF there is no common indicator, how can it be a diagnosis or a condition? What is absolutely impossible with e.g. schizophrenia that is possible with no schizophrenia?

Since paranoid schizophrenia could be just a person who is worried, which doesn't exclude anything does it.

Doctors are trained not to diagnose a patient subjectively, but to use objective criteria. Psychologists and psychiatrists worldwide have agreed on a set of criteria, by which each doctor should arrive at the same diagnosis, if faced with the same patient.

The current practice is that all mental disorders are defined by a list of symptoms. If a patient shows a certain minimum number of symptoms from this list (no matter, which), it is assumed that he is very probably suffering from that disorder. A sample can be found under the section "Criteria" in the Wikipedia article on Schizophrenia.

This is the currenty way to diagnose a mental disorder, because, despite all its weaknesses (see the section "Criticsm" in the DSM Wikipedia article for an overview), it is believed to be the best of all bad methods (akin to Churchill on democracy) and no replacement has yet been found (unless you count Antipsychiatry as helpful in dealing with mental problems).

The lists of criteria and the minimum number of symptoms are given in the Diagnostic and Statistical Manual of Mental Disorders (currently DSM-IV-TR) and the International Statistical Classification of Diseases and Related Health Problems (currently ICD-10).

As you can conclude from this, a mental disorder is not a reality. It is a construct that consists of a collection of possible symptoms. The "actual state", as you call it, the physiological reality, is not accessible to the psychologist or psychiatrist.


Consistent neuroanatomy coordinates naming I'm studying brain anatomy but I find coordinates systems are not consistent among books, lecture notes and internet.

There are 3 plane directions

horizontal
coronal
sagittal

And 6 directions

superior
inferior
anterior
posterior
medial
lateral

What I actually find is that the same "view" of the brain often have different names, and different views have the same name. I wanted to get rid once and forever to all ambiguity.

How do I call a radiograph taken on:

horizontal plane and looking from superior direction?
horizontal plane and looking from inferior direction?
coronal plane and looking from anterior direction?
coronal plane and looking from posterior direction?
sagittal plane and looking from medial direction?
sagittal plane and looking from lateral direction?

How do I call a radiograph taken from:

above the brain without "cutting" it?
below the brain without "cutting" it?
the front of the brain without "cutting" it?
the back of the brain without "cutting" it?
the left side of the brain without "cutting" it?
the right the brain without "cutting" it?

Another anomaly is that left/right is different. Other directions are from a point external to the body to another point external to the body (in example, superior seems to go from below the feet, to above the head), while medial, seems to indicate going from the center of the body, to the left or right side.

I'm not familiar with radiography, only MRI, but I assume conventions are similar. By convention images are always shown as if in front of the subject, or looking at the subject's feet (from below). There might be specific names for the direction of the cut (from top or from below) but they are not common (I've never heard them). Usually to avoid ambiguity you would always present cuts in the standard orientation. You can describe the cut ("coronal" or "axial") but images are usually self-explanatory.

For planes there are multiple names being used. The most common, in my experience, are axial, sagittal and coronal. But you will occasionally see respectively horizontal, medial and frontal. The 3 axes orthogonal to these planes and their associated orientations are the superior/inferior axis, the left/right axis and the anterior/posterior axis. Again, these cuts will usually always be shown from front, or from below. If, for any reason, someone decided to present a different orientation that would be specified explicitly. The sagittal cut is unambiguous, but usually you'll see it with the patient pointing left.

I don't know the name of an image "without cutting it", but I would assume it is just a "projection". And I would assume that unless specified explicitly orientations would be the same as cuts. Indeed, the orientation conventions used in modern imagery have been inherited from the old-age radiographic plates. While drawings are usually depicted as seen from top because it makes more sense to look at a brain from the top during a dissection.

Left/right is useful to describe the overall orientation of a subject, but not of an area in the brain (area X is to the right of area Y is true only in one hemisphere), so these directions are replaced by medial/lateral for brain locations. For some reason superior/inferior are also replaced by dorsal/ventral, I don't know why. For example the dorso-lateral PreFrontal Cortex is the "outer-top" part the the PFC. The ventro-lateral PFC is the "outer-bottom" part. And the ventro-medial PFC is the "inside" of the PFC (that you cannot see looking directly at the brain). Even weirder anterior/posterior are kept, but rostral/caudal are also used. To make it even more confusing these 2 axes do not perfectly match (rostral points toward the front for the anterior parts of the brain but down for the posterior parts of the brain). The axial plane for the brain is defined by the interaural axis and the lower ridge of the eye sockets. Brain coordinates are usually (at least in the scientific literature) reported by their position on the antero-posterior and medio-lateral axes. The origin of the system is the midpoint of the interaural axis.

Unfortunately there is more terminology that you'll find. For example referring to other parts of the brain, like "occipital". Different reference system are often mixed, like Caudal IntraParietal vs. Anterior IntraParietal. So long story short, there is no consistent coordinate system. It is truly unfortunate that terms used to disambiguate brain locations are themselves source of confusion.

Here is an example of macaque MRI with from top-left rotating counter-clockwise, an axial cut, a sagittal cut and a  coronal cut. I labeled directions for clarity.


Are association, conditioning, and symbolic learning the same thing? Symbols:
Our brains are able to understand that some things stand for other things. For example, the sound we make when we say "food" stands for things we can eat. And with writing, we can say that words have meaning because they stand for things in the real world.

Association: A brand is what someone associates with a company. I associate McDonalds with delicious, unhealthy food.

Conditioning: And I can associate other things. I might feel bad when I hear a certain song because it was playing during a bad breakup.

Is associating things an entirely different process from linking things together to create symbols?

Conditioning is considered an example (type) of association by associationism, a school of philosophy in psychology that suggests that all mental processes may be based on similar or proximal mental states.  Usually this idea is too broad and vague to be very practical to apply, but it has spawned a number of useful fields of study, including connectionism, a general strategy used in neural networks and learning modelling, and schemata, used in memory research.

Using connectionist models, artificial neural networks have demonstrated learning in a variety of subject areas, including operant and classical conditioning (examples of association), and handwriting recognition and sign reading (examples of symbols).  This suggests that the process involved may be essentially the same.

One of the major challenges to basic associationism has been that in practice, associations do not seem to obey any straightforward rules.  For example, children learn to associate words like "food" with their meaning very quickly with few (sometimes no) repetitions, while branding requires many more repetitions, and other associations (there is nothing intrinsically bad about this song) may never be learned.  For this reason, more rigorous theories, such as conditioning, are preferred.


Hearing Loss and Potentially hearing more I've been diagnosed since I was younger (2nd grade) with a hearing impairment. Basically the nerve hairs on my cochlea are burned and I don't pick up 70% of the frequencies around me in my right ear.

My question is whether people can be born with a higher level of hearing? Or does it stop at 100% hearing, like 20/20 vision?

Short answer
People with above-normal hearing exist.

Background
Normal hearing was defined as the average of a group of young healthy individuals. These normal hearing levels are currently used to express acoustic sensitivities. One commonly used way is to use decibels relative to this normal hearing level (dB NH). This scale is used in audiograms (Schnupp et al., 2012). When hearing senstivities are reduced by 20 dB or more it is regarded as diagnostic for hearing impairment (Fig. 1).

Fig. 1. Audiogram. Source: (Schnupp et al., 2012)

Statistical outliers always exist. In Fig. 2 is an audiogram showing above-normal hearing sensitivities in the low frequencies in the left ear and in the high frequencies in the right ear (Fig. 2).

Fig. 2. Audiograms showing normal hearing (solid lines) and noise-induced hearing loss (dotted lines) Source: Fraser University, CA.

Reference
Schnupp et al., Auditory Neuroscience, MIT Press 2012


Why are most people right handed? How did right handedness win over left handedness in numbers?

Is it only a coincidence that there are more right handed people than left handed ones? Or, has some effect in nature explicitly made right handedness dominant?

First of all, asymmetries in apparently symmetric creatures (of which most are) are actually quite typical.  However, in most cases of hand dominance, there is no population-wide hand dominance.  In other words, the population is split 50/50 between left and right handers.  In humans, however, a lack of hand dominance is often associated with cognitive deficits.

In humans, population-wise, we are right-hand dominant (9:1).  There are exceptions to a genetic influence, such as strict schools disciplining children into using their right hand, or an indirect consequence of developmental brain trauma or genetic diseases, but for the most part the right-hand dominance is thought to be a genetic outcome based on the emergent effects of several interacting genes.  That is, there's no particular reason why nature "chose" right over left, just that having a dominant hand allows for more specialization with respect to tool-using which could possibly have given humans with this mutation a competitive edge over their ambidextrous competitors.

A single-gene theory (Corballis, 2009) proposes that there is a dextral and a chance allele of a particular gene and that people born with the dextral allele are likely to be right-handed while people born with the chance allele have equal chance of being left or right-handed.

Francks, C; DeLisi, LE; Fisher, SE; Laval, SH; Rue, JE; Stein, JF; Monaco, AP (2003). "Confirmatory evidence for linkage of relative hand skill to 2p12-q11". American journal of human genetics 72 (2): 499–502. (PDF)
Van Agtmael, T; Forrest, SM; Williamson, R (2002). "Parametric and non-parametric linkage analysis of several candidate regions for genes for human handedness". European journal of human genetics : EJHG 10 (10): 623–30.
Warren, Diane M.; Stern, Michael; Duggirala, Ravindranath; Dyer, Thomas D.; Almasy, Laura (2006). "Heritability and linkage analysis of hand, foot, and eye preference in Mexican Americans". Laterality: Asymmetries of Body, Brain and Cognition 11 (6): 508–524.
Scerri, T. S.; Brandler, W. M.; Paracchini, S.; Morris, A. P.; Ring, S. M.; Richardson, A. J.; Talcott, J. B.; Stein, J.; Monaco, A. P. (2010). "PCSK6 is associated with handedness in individuals with dyslexia". Human Molecular Genetics 20 (3): 608–614.
Michael C Corballis. (2009) The evolution and genetics of cerebral asymmetry.  Phil. Trans. R. Soc. B 12, 364 (1519): 867-879


Why can't we understand text without subvocalizating it? I wonder why can't we understand text the same way we understand pictures?

Everything we see but text we understand without the inner voice, we don't subvocalize/describe a forest, a street or anything. We just understand it.

Why can't reading work the same way? When I look at words I recognize them but they have no meaning until I read them in my mind.

Is there even anyone who got rid of subvocalization completely and can read a 300 page book just in one evening understanding pretty everything?

It even works the same the other way around. If I try to see a textural representation of some thing like let's say a table, I first have to say in my mind. Why is it so? It's really annoying.

text > voice (in my mind) > understanding

why not

text > understanding

I also don't get it why people consider this normal. It slows everything down. Imagine you could read a book in a single eventing if not the subvoc. We must do something terribly wrong when learning to read.

I'm not asking about speed-reading because subvoc is not only an issue there - although it is most noticable when reading - but it also interfers when thinking and forces you to say your thoughts.

In japanese language, kanjis are more than phonemes but represent an idea. For instance, both tree and spirit have the same sound (ki) and can be written with the hiragana "letter" き. But when kanjis are used tree is 木 while spirit is 気.
Therefore, it is possible to read without subvocalizing. We can read as if it was graphics.
So, when using kanji is much more like text > undestanding.
But is hard to think doing it purely because we use many words that have no physical meaning such as "as", "such", "meaning" etc.


Where can I find online interactive versions of classic experiments in psychology for the purposes of teaching? It's often useful and fun for students to experience well-known psychology experiments. Where can demo versions of famous psychology experiments be found online?

Some example paradigms that might be useful include:

Stroop
IAT
N-back
Visual search, particularly pop-out effects

List presented alphabetically

Cambridge Brain Sciences (cambridgebrainsciences.com)

Several "brain-training" type experiments including span tasks, mental rotation, and paired associate memory. Some tests require free registration on the site to complete. Data from the tests may be used for research purposes. Created by Adam Hampshire and Adrian Owen at University of Western Ontario.

Cognitive fun! (cognitivefun.net)

Several n-back variants, basic response time tests (e.g. go/no-go), subitizing demo, flanker task, working memory span. Creator/source unclear.

Dual-Task (dualtask.org)

Demonstrations of multi-tasking limitations. Experiments are Java applets. Site created by Hal Pashler at UCSD.

Go Cognitive (gocognitive.net)

Several cognitive experiments, including change blindness, visual search, implicit memory test, working memory capactiy, and selective attention. Experiments are Flash based. Site created by team at the University of Idaho.

Project Implicit (https://implicit.harvard.edu/implicit/takeatest.html)

Many variations on the implicit association test. Data is collected for research purposes. Created by team at Harvard University.

Simons Lab (simonslab.com)

Several videos of classic selective attention / inattentional blindness studies, including the famous gorilla study. Students can do the gorilla study by watching a YouTube video. Videos of other experiments are more descriptive and less interactive. Site created by Daniel Simons at the University of Illinois.

Stroop demos

http://ezyang.com/stroop/ - sequential presentation of words, press key to respond.
https://faculty.washington.edu/chudler/java/ready.html - simultaneous presentation of whole list. read aloud and hit button to indicate that reading is complete.
http://www.math.unt.edu/~tam/selftests/stroopeffects.html - simultaneous presentation of whole list. read aloud and hit button to indicate that reading is complete.

Swarthmore Cognitive Psychology Demos (http://cogscidemos.swarthmore.edu/)

Three experiments: Visual search, Sternberg working memory task, & reverse Stroop. Implemented in JavaScript. Some parameters of trials can be adjusted. Data is nicely summarized at the end of the experiment, e.g. search functions are fit for the visual search task. Created at Swarthmore under the direction of Frank Durgin.


What was the experiment where a person is given something and then has to share it with another person Bob is given a bar of chocolate by the experimenter. Then he is to propose how he will share the chocolate with Emilly. If Emilly agrees with Bob's proposal, the kids will each get their share. If Emilly disagrees, nobody gets anything.

The experiment demonstrates that Emilly will refuse a profitable share (anything more than no chocolate is profitable for her), if the split Bob proposed would be "unfair".

The experiment you are referring to is usually called the ultimatum game, and was first experimentally tested by Güth, Schmittberger, and Schwarze in 1982 [1].

[1]  Güth, Werner, Rolf Schmittberger, and Bernd Schwarze. "An experimental analysis of ultimatum bargaining." Journal of Economic Behavior & Organization 3.4 (1982): 367-388. PDF


Is consistent dual n-back training likely to improve the performance of analysis (mathematics) students? Suppose you isolate a class of undergraduate mathematics majors who are about to enroll in a semester of real analysis (rigorous, proof-based calculus) and split them into two groups. Then, you schedule the first group to study n hours of real analysis every week and the other group to study (n-m) hours of real analysis every week and perform m hours of n-back training (assume that n and m are reasonably well tuned; m is probably much smaller than n).

Also assume that the second group does not take shortcuts in doing the training (where certain patterns are exploited).

Which group do you conjecture to perform better in the analysis
course and why?
To what degree will one group perform better and why?
Does having a wider short-term memory horizon of numbers (which I
assume n-back produces) result in being able to keep track of more
variables and rigorous proof steps in a sharper way (working memory)
and in faster comprehension of mathematical concepts (fluid
intelligence)?
Does the training result in a larger attention span and therefore to
better grades?

I assume that the group that  spends 100% of their time studying real analysis and 0% of their time doing n-back training will do best in any subsequent real analysis course.

Cognitive skill acquisition does not generalise all that much (for a review see VanLehn, 1996). Transfer is often limited. I'm sceptical of any claims that short term training can lead to far reaching cognitive change as implied by n-back training.

The demands on working memory of problems in a domain get less as the knowledge and rules implied by a domain get better acquired. Over time students will start to recognise patterns, and will learn to apply rules specific to the domain. Domain specific practice is probably the best way to acquire that knowledge. And in general, the more time that is spent on learning that knowledge, the more knowledge that will be acquired.

Of course, much could be said about creating an optimal learning environment for real analysis. For example, consolidation of prerequisite knowledge, providing practice at the right level of difficulty, providing feedback to the learner, providing a good mix of presentation of content with problem exercises, distributing practice over time, and so on are all important components of an effective learning environment. However, these have nothing to do with n-back, and everything to do with good pedagogy. In particular, if you want to teach something other than real analysis, but your aim is effective performance in real analysis, then you should examine what are the relevant skills and prerequisites for effective performance in real analysis. And combine this with an examination of student difficulties and knowledge gaps.

Empirical Evaluations

@Ofri Raviv pointed out two references (Shipstead et al, 2012; Melby-Lervag et al, 2013) that provide reviews of working memory training and are generally critical of its utility.

Melby-Lervag and Hulme (2013) did a meta-analysis of working memory training studies:

  To be included in the review, studies had to be randomized controlled
  trials or quasi-experiments without randomization, have a treatment,
  and have either a treated group or an untreated control group.
  Twenty-three studies with 30 group comparisons met the criteria for
  inclusion. The studies included involved clinical samples and samples
  of typically developing children and adults. Meta-analyses indicated
  that the programs produced reliable short-term improvements in working
  memory skills. For verbal working memory, these near-transfer effects
  were not sustained at follow-up, whereas for visuospatial working
  memory, limited evidence suggested that such effects might be
  maintained. More importantly, there was no convincing evidence of the
  generalization of working memory training to other skills (nonverbal
  and verbal ability, inhibitory processes in attention, word decoding,
  and arithmetic). The authors conclude that memory training programs
  appear to produce short-term, specific training effects that do not
  generalize.

References

VanLehn, K. (1996). Cognitive skill acquisition. Annual review of psychology, 47(1), 513-539.
Shipstead, Zach; Redick, Thomas S.; Engle, Randall W. Psychological Bulletin, Vol 138(4), Jul 2012, 628-654. doi: 10.1037/a0027473
2
Melby-Lervag, M., & Hulme, C. (2013). Is working memory training in children effective? A meta-analytic review. Developmental Psychology, 49, 270-291. PDF


How does parental expectation lead a child from adaptive perfectionism to rebelliousness? I find many sources saying that parents with perfectionist ideals can ultimately push a child to shed his or her attitude of wanting to please their parents and become rebellious. What I cannot find is an explanation of the mechanism behind this change. Are there any theories or studies that attempt to explain this reversal of character?

Sources:

Rimm (essay)

Parents.com (article - anecdotal)

Childhood/adolescent rebelliousness could be explained by psychological reactance theory (Brehm, 1966) and self-determination theory (Ryan & Deci, 2000).

Psychological reactance theory, Brehm states:

  The idea fundamental to reactance theory, namely, that people become motivationally aroused by a threat to or elimination of a behavioral freedom. This motivational state is what is called psychological reactance. It impels the individual to restore the particular freedom that was threatened or taken away. It does not impel the individual to acquire just any freedom--only the one threatened or taken away will do.

Psychological reactance would be elicited when freedom is taken away, thereby motivating individuals to engage in oppositional behavior. It follows that it parents are perfectionist they would be more likely to take away freedom from their child.

Self-determination theory:

Central to SDT are the basic psychological needs for autonomy, relatedness, and competence. When satisfied, these needs foster growth and psychosocial
adjustment. When frustrated, people would display maladjustment and psychopathology (Ryan & Deci, 2000; Vansteenkiste & Ryan, 2013).

Essentially "Don't tell me what to do"

Another idea is that parental pressure can create a lot of stress, and that rebelling or dropping out is simply a reaction to this stress. Stoeber & Rambow (2007) found that:

  Parental pressure to be perfect and negative reactions to
  imperfection, are associated with the motivation to avoid failure and
  low well-being and thus may undermine healthy adolescent development.

However they do also go on to say:

  Not all aspects of perfectionism are neurotic, unhealthy, or maladaptive. On the contrary, strivingfor perfection can form part of a healthy pursuit of excellence (Shafran, Cooper, & Fairburn, 2002) and may be adaptive in achievement situations where perfectionistic strivings could provide
  students with additional motivation to do their best and thus achieve better grades.

It appears to me that children/ adolescents reaction to perfectionist parenting is not a change in character, but just a reaction to the environment that has been created for them.

References:

Brehm, J. W. (1966). A theory of psychological reactance.

Deci, E. L., & Ryan, R. M. (2000). The" what" and" why" of goal pursuits: Human needs and the self-determination of behavior. Psychological inquiry, 11(4), 227-268.

Stoeber, J., & Rambow, A. (2007). Perfectionism in adolescent school students: Relations with motivation, achievement, and well-being. Personality and individual differences, 42(7), 1379-1389.

Vansteenkiste, M., & Ryan, R. M. (2013). On psychological growth and vulnerability: Basic psychological need satisfaction and need frustration as a unifying principle. Journal of Psychotherapy Integration, 23(3), 263.


How to get rid of subvocalization? When I read a text written in latin alphabet and I want to understand what it means I usually

transform each word into spoken word (internal speech) and
then I transform it into meaning.

I can't get rid of the first phase and reduce the reading process to the second phase only. In Wikipedia, this internal speech is described as subvocalization.

When I read in chinese I'm able to leave out subvocalization and go directly to the meaning. In many cases I learned only the meanings of symbols without knowing how to pronounce the symbol. I'm leaving out this mental burden and surf through the text without subvocalization. Reading is faster and my mind is in the relaxed state as if watching a movie without speech.

Are their some techniques I can learn to get rid of subvocalization when reading texts written in latin alphabet or cyrillic? Could you cite a few sources researching this skill?

The two legs upon which speed reading rests, in short, are chunking and seeking. Chunking is reading multiple words at once, while seeking allows you to find those chunks quickly and efficiently. The first exercise below will solve your subvocalization problems, but I recommend doing both in order to read text more effectively.

You'll need:

A computer with internet access for the first exercise
A stopwatch and notecards (or a flashcard system of any sort) for the second exercise

Practice Chunking with Spreeder

Many combinations of words can be comprehended simultaneously, which negates the need for subvocalization. Reading multiple words at once is called chunking. A useful tool to drill this skill is Spreeder, which breaks text into arbitrary chunks and displays them a chunk at a time.

Go to www.spreeder.com
Click to speed read the introduction
Click "spreed!"
At the bottom right, click "settings" and increase chunk size to 3
Increase wpm as desired

Practice Seeking with flashcards

After you are comfortable speed reading on spreeder at a high level, which should have solved your subvocalization problem, move on to seeking. Spreeder displays chunks right in the middle of the screen, which is predictable. Real world text, however, is not that convenient.

Still, Spreeder can be helpful.

"Spreeder" some text with chunk size 3
Write those chunks down on your flash cards
Pull up or print out the original text
Shuffle the flash cards and pull them at random
Identify the random chunk in the text as fast as possible
Use the stopwatch to time yourself after identifying 10 chunks

Doing this for 15 minutes a day will vastly improve your reading speed.

  This was the basis of the speed reading course I took at the University of Illinois at Urbana-Champaign. I can't cite any research from this coffeehouse, but give it a shot and see for yourself. Personally, I read casually at 500wpm at 90% comprehension and I can read up to 800wpm at 60% comprehension. I've been able to read like this since before the class, though, so feel free to take it with a grain of salt.


What if people understand or interpret words differently in their mind? Let's think about it, we have all adopted to learn the meaning of words through experiences or emotions. We didn't learn each and every word from a dictionary. What if I understand a word slightly differently in my complex mind? Could it result in some sort of pessimistic or optimistic or abstract outcome? And how often is this case true in our society?

Quite certainly this is the case (even if you learn all words from a dictionary), but this is more of a philosophical debate. It is unclear what you are after when referring to 'pessimistic', 'optimistic', or 'abstract' outcomes, but I can point you in the right direction in case you want to read up more on this subject.

One concept that comes to mind from linguistics and philosophy of language is  indexicality.

  ... an indexical behavior or utterance points to (or indicates) some state
  of affairs. For example, I refers to whoever is speaking; now refers to the time at which that word is uttered; and here refers to the place of utterance.

However, some argue the same holds true for almost any utterance. (Suchman, 1986)

  Among philosophers and linguists, the term indexicality typically is
  used to distinguish those classes of expressions whose meaning is
  conditional on the situation of their use in this way from those such
  as, for example, definite noun phrases whose meaning is claimed to be
  specifiable in objective, or context-independent terms. But the
  communicative significance of a linguistic expression is always dependent on the circumstances of its use. A formal statement not of
  what the language means in relation to any context, but of what the
  language-user means in relation to some particular context, requires a
  description of the context or situation of the utterance itself. And
  every utterance's situation comprises an indefinite range of possibly
  relevant features. Our practical solution to this theoretical problem
  is not to enumerate some subset of the relevant circumstances—we
  generally never mention our circumstances as such at all—but to "wave
  our hand" at the situation, as if we always included in our utterance
  an implicit ceteris paribus clause and closed with an implicit et
  cetera clause.

Suchman, L. (1986). Plans and situated actions. New York, Cambridge University.


What research has modelled the difficulty of mental mathematical calculation? I posted this also on mathoverflow.

What research has modelled the difficulty of evaluating a formula mentally (for your average, numerate, person, not a trained mental calculator)?

For instance, evaluating an arithmetic expression requires in general requires three registers, but some only require two and are considerably easier to deal with. Additions is easier than subtraction which is easier than multiplication which is easier than division. Multiplication by small integer number is easy, as are multiplications and divisions by 2,5,10...

Many rule of thumbs are intuitive, but I'm looking for a more comprehensive work on the topic.

There is a huge amount of research on this topic, particularly in developmental psychology.

Siegler: As @Joel has noted, Robert S. Siegler provides a great entry point into this literature (see his list of selected publications with PDFs). He has done a lot of research on the strategies that children use to solve mathematical problems. His research includes both empirical and computational modelling approaches. He also has a number of studies that compare performance across features of arithmetic problems. For example, you could look at Siegler and Lemaire (1997) which shows in an adult sample the differences in speed and accuracy for different kinds of multiplication problems (e.g., multiples of 10 or not, single versus double digits). As another example, Siegler and Shrager (1984) show empirical error rates and strategy use in children for all possible combinations of single digit addition.

Act-R: There are also a number of publications using the ACT-R framework on mathematical problem solving (see this list from the ACT-R website). Perhaps check out Ritter et al (2007) for a review.

Defining difficulty: In general, there are questions about how you would define difficulty.
Typical indicators would include task completion time and accuracy.
Also, when talking about the difficulty of a mathematical operation, you need to consider the strategy that an individual is using. In particular, there is general shift with practice from using an algorithmic strategy to using a retrieval strategy (for a review, see Delaney et al, 1998). Thus, at first children use strategies like repeated addition to solve multiplication problems whereas with practice, they typically learn to retrieve the answer from memory. The ability to retrieve is broadly related to the number of times the specific problem has been encountered with the correct answer available, along with forgetting effects related to periods where there is no exposure.

References

Delaney, P.F., Reder, L.M., Staszewski, J.J. & Ritter, F.E. (1998). The strategy-specific nature of improvement: The power law applies by strategy within task. Psychological Science, 9, 1-7. PDF
Siegler, R. S., & Lemaire, P. (1997). Older and younger adults' strategy choices in multiplication: Testing predictions of ASCM via the choice/no choice method. Journal of Experimental Psychology: General, 126, 71-92. PDF
Siegler, R. S., & Shrager, J. (1984). Strategy choices in addition and subtraction: How do children know what to do? In C. Sophian (Ed.), The origins of cognitive skills (pp. 229-293). Hillsdale, NJ: Erlbaum.
PDF1
PDF2
Ritter, S., Anderson, J.R., Koedinger, K.R. & Corbett, A. (2007). Cognitive Tutor: Applied research in mathematics education. Psychonomic bulletin & review, 14, 249-255. PDF


Can one alter their auditory perception? I'm coming from the idea that the way we perceive sound is a reaction to a certain signal, sent to our brain by ears. Of course this feeling intensifies as volume of the sound increases and our ears send us a stronger signal.

Now here I am wondering if we can augment that signal in our brain, so when the volume stays the same - we will be able to perceive it louder. Can that be done without any kind of chemical or surgical intrusion, just by sheer force of will? Do such perception "controllers" even exist and we just haven't learned to control them?
This question is about auditory system, but since it touches the brain signal interpretation you could explain this from a different perspective (visual or even tactile).

This isn't part of the question, but I also wonder, if previous is possible, than can the same be done to mentally create sounds in your head and hear them as if they were real..?

Imagine a music recording studio, with a band playing in the soundproof room.  Now imagine 2 mic->speaker connections: A mic inside the room records the music, and plays it on a speaker outside, and then another mic records the sound coming out of that speaker, and delivers it to the recording equipment.  You can imagine the loss of quality involved in that set up I'm sure, but bear with me.  Both mic->speaker connections are set to 50% volume.  Say we want to increase the volume: We can increase the volume on either connection (or both).  If we increase the volume to 100% on only one of the 2 connections, then the volume of the recorded sound will increase by approximately the same amount whichever one we choose.  However, increasing the volume of the first connection is better - it results in a better quality recording.  This is because each connection can only lose quality, not add it.

Now, supposing that the first mic->speaker connection represents the auditory nerve (ear -> primary auditory cortex), and the second connection represents "perception" (auditory cortex -> rest of brain), then we can discuss increasing the "volume" at either "connection" via conscious control (I'm assuming that this is what you mean by "force of will").

The auditory nerve passes through the central auditory system, an area of the brain considered unconscious:

  Damage to the Primary Auditory Cortex in humans leads to a loss of any
  awareness of sound, but an ability to react reflexively to sounds
  remains as there is a great deal of subcortical processing in the
  auditory brainstem and midbrain.

In other words, so far as we know, there is no conscious control over this "connection".

Neuroplasticity of "perception" is much greater.  A variety of studies have shown certain improved hearing capabilities in blind people, correlating with how early hearing loss occurs (the earlier the better), and the involvement of neuroplasticity as the visual cortex can be usurped for auditory processing.  Whether or not this corresponds to a change in "volume" is unclear, and this effect does not appear to be "consciously" controlled.

However, more recent research has demonstrated how similar effects can be induced in non-blind adults: Through temporary blindness (as little as 90 minutes with a blindfold).  Corresponding research on mice has shown that this may be the result of increased "volume" in perception:

  The cells fired faster and more powerfully in response to sounds and
  were more sensitive to quiet sounds.

So not exactly "sheer will", but temporary blindness, that you can easily induce on yourself consciously, may improve certain aspects of hearing, possibly including "volume".

Hope this helps.


What computerized EEG analysis algorithms are there? I got a commercial-grade EEG headband and am trying to look at the data it outputs. The headband quantifies raw EEG signal from a single forehead dry sensor into a range of EEG bands (alpha, beta, etc). The issue that I'm running into is that the values of the EEG bands jump rather significantly from one data point to the next (0.05 second reading intervals). Additionally, there are eye-related artifacts.

I would like to apply some sort of algorithm or statistical analysis to see how the EEG bands behave over some time interval.  I'm hoping to see if some EEG band statistically rises or is suppressed over 5-15min time period. Seeing instantaneous jumps in individual readings does not convey this information.

For example, I know that for Actigraphic studies, there are sleep scoring algorithms, like one by Cole that looks at the previous 4 minutes, the current minute and 2 minutes in the future to score a minute of actigraphy data:

 SleepScoreConstant*
(550*4minAgo + 378*3minAgo + 413*2minAgo + 699*1minAgo
+1736*CurrentMinute  +
287*1minAhead + 309*2minAhead)

Are there some similar algorithms for EEG band analysis?

Alternatively, it would help if you can suggest the realistic time window over which EEG bands may be statistically analyzed in awake subjects: is it 20 seconds? 5 minutes? 90 minutes?

http://sccn.ucsd.edu/eeglab/

http://chronux.org

are two libraries with tons of functions for analyzing eeg and emg data


What are the mathematical models of memory? Are there mathematical models of memory in humans or animals?

I want to know how neuroscientists use mathematics to describe memory in living creatures. How do neuroscientists model memory and show how it works by mathematics?

I am a theoretical physics PhD student, and interested in neuroscience too. The only tool which I have and I could use to study neuroscience is mathematics and programing. That's why I want to know how neuroscientists address the memory by mathematics. I know how math works to describe neurons oscillations and action potential, but I don't know how it works for memory.

Any reference or review article is welcome too.

Very many references may easily be found with a Google search for "mathematical model memory". Probably the most classic and iconic reference is Atkinson and Shiffrin (1965), which is also described on Wikipedia. Its three components and their relationships are nicely encapsulated in this figure:

Many other, lesser-known mathematical models of memory exist, including but not limited to these:

A model of recognition memory (Atkinson & Juola, 1974)
A model of the circular process in short-term memory (Min'ko & Petunin, 1981)
An application of interference theory to memory retention failures (Anninos, 1972)
A model of hippocampus activity involving affine and chaotic rules (Yamaguti, Kuroda, Fukushima, Tsukada, & Tsuda, 2011; see also Tsuda, Yamaguti, Kuroda, Fukushima, & Tsukada, 2008; Fukushima, Tsukada, Tsuda, Yamaguti, & Kuroda, 2009)
A computer simulation model of short-term learning (Anderson, 1983; see also a simpler model proposed by Hicklin, 1976, cited in a review of Anderson's article by Preece & Anderson, 1984)
A computer simulation model of operant conditioning (Bower, 1967; Mandler, 1967)
The Hopfield (1982, 1984, 2006) neural network model of associative memory (Rojas, 1996; see also Wikipedia; thanks @Memming!) describes neural activity as binary, the attributes of memories as state space locations, and the system as governed by a Lyupanov function. Much more could be said about artificial neural network models of memory in general (e.g., LSTM, Hochreiter & Schmidhuber, 1997; ART, Carpenter & Grossberg, 1987a, 1987b).

You may also be interested in the following references:

A book chapter, "Mathematical models of human memory" (Raaijmakers, 2008)
A book, Mathematical Models in Psychology (Restle, 1971)
Rojas' (1996) entire book, Neural Networks: A Systematic Introduction seems pertinent. (And free!)

And a related question here, in which "memory" comes up twice:

https://cogsci.stackexchange.com/q/1391/4086

References
· Anderson, O. R. (1983). A neuromathematical model of human information processing and its application to science content acquisition. Journal of Research in Science Teaching, 20(7), 603–620.
· Anninos, P. A. (1972). Mathematical model of memory trace and forgetfulness. Kybernetik, 10(3), 165–167.
· Atkinson, R. C., & Juola, J. F. (1974). Search and decision processes in recognition memory. In D. H. Krantz, R. C. Atkinson, R. D. Luce, & P. Suppes (Eds.), Contemporary developments in mathematical psychology: I. Learning, memory and thinking. Oxford, England: W. H. Freeman.
· Atkinson, R. C., & Shiffrin, R. M. (1965). Mathematical models for memory and learning. Technical Report No. 79: Psychological Series. Institute for Mathematical Studies in the Social Sciences, Stanford University. Retrieved from http://www.rca.ucsd.edu/selected_papers/IMSSS_79.pdf.
· Bower, G. (1967). A multicomponent theory of the memory trace. In K. W. Spence & J. T. Spence (Eds.), The psychology of learning and motivation: I. Oxford, England: Academic Press.
· Carpenter, G. A., & Grossberg, S. (1987). ART 2: Self-organization of stable category recognition codes for analog input patterns. Applied Optics, 26(23), 4919–4930. Retrieved from http://www.opticsinfobase.org/ao/fulltext.cfm?uri=ao-26-23-4919&id=30891.
· Carpenter, G. A., & Grossberg, S. (1987). A massively parallel architecture for a self-organizing neural pattern recognition machine. Computer Vision, Graphics, and Image Processing, 37(1), 54–115. Retrieved from http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.70.9588&rep=rep1&type=pdf.
· Fukushima, Y., Tsukada, M., Tsuda, I., Yamaguti, Y., & Kuroda, S. (2009). Coding mechanisms in hippocampal networks for learning and memory. In Advances in Neuro-Information Processing (pp. 72–79). Springer: Berlin Heidelberg.
· Hicklin, W. J. (1976). A model for mastery learning based on dynamic equilibrium theory. Journal of Mathematical Psychology, 13(1), 79–88.
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· Hopfield, J. J. (2008). Searching for memories, Sudoku, implicit check bits, and the iterative use of not-always-correct rapid neural computation. Neural Computation, 20(5), 1119–1164. Retrieved from http://arxiv.org/ftp/q-bio/papers/0609/0609006.pdf.
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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?

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.


Why do drivers not slow down when they see signs indicating road work? I found the following anecdote on Quora

Many years ago, I worked for a gas & electric power company, and had
been a member of a crew installing a road-side gas main. Despite the
signs, flashing lights, and traffic cones we'd set up well in advance
of the work zone, the overwhelming majority of people would speed past
us--sometimes within an arm's length, seemingly having no regard for
our safety. Our supervisor showed up to check on our progress, and,
witnessing the danger, he walked to our truck, took out a yellow
compressor hose, and rolled it out across the road. Immediately &
without exception, from that point on, every single car slowed down
before driving over the hose.

This is the worker's interpretation of the behavior:

In my youthful mind, I concluded that people were simply more
concerned about damaging their cars than they were about damaging
other people, but in my now middle-aged mind, I believe it's more
complex than that. Maybe it's one of those countless subconscious,
split-second decisions our minds have to make throughout each day,
assessing probabilities & adjusting accordingly: 'I see the road crew,
I've never struck a person with my car before, it's much more likely
than not that I won't strike a person today, and those people are
aware of my car & have the ability to avoid it, therefore, carry on.'
[versus] 'I see an object on the road, I see that I can't avoid the
object, I've experienced damage to my car before when driving over
objects in the road, and that object isn't going to move, therefore,
caution is merited.'

Is this interpretation correct?

Presumably the decision of drivers to slow down in response to work zone signage is influenced by many factors.

Signage and road factors: Presumably there are a wide range of factors related to the nature of the signs and the structure of the road setting that influence whether people slow down. For example, I've seen road work signage on freeways that were often in place even when no actual road work is occurring. In these cases I've seen many drivers slow down little if at all. In contrast, I typically see much greater reduction in speeds when actual road work is occurring. Or for example, I imagine that a worker standing with a sign would be more effective than a static sign.
Cultural and norm factors: Presumably countries and regions  differ in cultural attitudes to driving, the acceptability of speeding, and the general tolerance for risk taking. Road safety advertising employ a wide range of strategies for reducing speeding including targeting personal interest (e.g., you'll get fined if you speed) or highlighting consequences (e.g., speeding increases the likelihood of killing yourself and others).

A few empirical studies

Jarvis (1983) performed empirical research on Australian highways and found that

  There is a clear indication that work area speed limits reduce vehicle speed on entry into the work zone; however, the large majority of drivers still exceed the speed limit posted.

Garber and Patel (1995) found that signs triggered by radars indicating excessive speed were more effective in slowing cars than static signs.

References

Garber, N. J., & Patel, S. T. (1995). Control of vehicle speeds in temporary traffic control zones (work zones) using changeable message signs with radar. Transportation Research Record, (1509), 73-81.
Jarvis, J. R. (1983). The Effectiveness of Road Work Speed Limit Signs. Australian Road Research, 13(3).


Why are the ERP amplitudes recorded and analyzed from different software so different in voltage? Here are the two ERPs from the same study design, though different subjects. The largest amplitude in the 1st one goes up to 25 uv, while only goes up to 6 in the 2nd figure.

Differences: The 1st one were recorded with 60-channel Easycap, analyzed in Brain Vision, nose referenced; while the 2nd one were recorded with EGI 128-channel Geodesic Net, analyzed in Net Station, averaging referenced. Are these sufficient to explain the big difference in the voltages? Thank you!

The short answer is yes, probably.

Referencing is the process of subtracting a referent signal from all of your channels. While recording, the EEG data are typically online referenced to a vertex electrode, earlobes, back of the neck etc. During post collection processing EEG are most often rereferenced to the average reference, or the linked mastoids. The reference  that is selected changes the shape of the signal simply because the reference channel (or average signal if using more than one) are subtracted from every channel. This means that comparing results across data that have different references is not direct. Since referencing is linear it can typically be undone and the reference channel can be changed. I never use a nasion reference so I can't say for certain why the amplitude is so large but I would guess if you looked at the signal at that channel you would see how it is adding (if channel of interest is positive and referant is negative then amplitude goes up) to your electrode of interest or subtracting from it (if both are positive). For a P3 response 6 micro volts is reasonable. If you want a more detailed explanation of referencing I recommend Nunez's book, or another book on EEG data analysis and theory.


Is paraphilia a disorder? There has been some confusion in recent questions about the term paraphilia. In most questions and answers, including my own, paraphilias have been seen as disorders that might require treatment.

But are paraphilias disorders?

The DSM-5 does not list all paraphilia as a disorder! According to the DSM-5,

  The term paraphilia denotes any intense and persistent sexual interest other than sexual interest in genital stimulationor preparatory fondling with phenotypically normal, physically mature, consenting human partners.

What the DSM-5 does list are paraphilic disorders:

  A paraphilic disorder is a paraphilia that is currently causing distress or impairment to the individual or a paraphilia whose satisfaction has entailed personal harm, or risk of harm, to others. A paraphilia is a necessary but not a sufficient condition for having a paraphilic disorder, and a paraphilia b itself does not necessarily justify or require clinical intervention.

  In the diagnostic criteria set for each of the listed paraphilic disorders, Criterion A specifies the qualitative nature of the paraphilia (e.g., an erotic focus on children or on exposing the genitals to strangers), and Criterion B specifies the negative consequences of the paraphilia (e.g. distress, impairment, or harm to others). In keeping with the distinction between paraphilias and paraphilic disorders, the term diagnosis should be reserved for individuals who meet both Criteria A and B.


Are ambidextrous people better at multitasking? I'm strongly 'one-handed' in that I can barely even write with my left hand. My wife is fairly ambidextrous, in that she's by default left-handed, but can also write with her right hand.

I've noticed that she's capable of driving in the dark with full, stressful concentration and still be able to talk. Whereas I'd have trouble driving in the dark and holding a conversation at the same time.

I've heard that this is because one handed people have developed a side of the brain more strongly than the other, whereas ambidextrous people have developed both. Anything that implies that ambidexterity is a disadvantage for multitasking would also be helpful.

This might not answer the question well enough to count as a good answer, but if you're interested in handedness in general, I highly recommend Stanley Coren's well-written and well-researched "The Left-Hander Syndrome."

If I recall correctly, the book doesn't address multitasking specifically, but it does address many issues associated with handedness, including lateralization of language and identity, development of mood disorders, and behavioral differences (especially risk of injury) between left- and right-handers. You might get some good pointers by reading the references.


Is there evidence for a unique isolated internal representation of loved ones? Some time ago, I've read that the most significant people in a person's life have their own internal representation/model of within the person's mind. For example:

An internal representation of a spouse
An internal representation of parents, grandparents
An internal representation of children
Close friends, etc

This representation does not matter, until the connection is severed - the significant person dies or moves away. This is when there's no more input from the real world - only the internal representation remains. For example, it is possible to dream of an interaction with a deceased relative. My question is about whatever phenomenon causes people to be able to dream and interact with people previously known, while in a dream.

I'm interested if there has been research that confirms that people do indeed have unique internal models of significantly close relatives? If so, what is the correct term to use when searching for scientific information on the subject?

Update: In particular, I'm interested in unique internal representations - linked to a unique object in real life. Do they exist?

For example, there is only one spouse. Jane Smith. Has there been evidence that the internal representation of Jane Smith is unique (every single time Jane Smith is encountered, it is the same representation, possibly lighting up the same region of the brain if viewed with imaging techniques).

Alex, the following few remarks hardly deserve the status of an answer, but I think your interesting question, taken with with Greg's pertinent rider, makes it worth sharing a couple of ideas, even at the risk of downvotes from the type of churls and trolls I have already become familiar with on math stack exchange.

really I just want to relate your question to a couple of other well-known phenomena in our mental life.

firstly, I have occasionally thought that there is a curious analogy between the sufferings related to grief (whether through bereavement or various forms of traumatic separation - e.g. at adoption, or in certain cases of asymmetric relationship breakdown) and the discomfort sometimes experienced after surgical or traumatic amputation known in the literature as phantom limbs. personally I think this analogy tends to support some form of the hypothesis you propose regarding internal representations.

Greg's question is useful: how can one distinguish such internal representations from memories? of course it all depends what is meant by memory. so your question could, if necessary, be rephrased as a question about certain high-level structural aspects of memory and perception. in this context it is also worth noting that the same type of things we call self-awareness, recognition of others, and grief, have been attributed to non-human animals, particularly some species of mammals and birds.

my personal academic study of psychology took place in the early 1970's. this was an interesting time, because the intellectual bankruptcy of the still-dominant behavioristic paradigm had recently become very apparent due to its utter inadequacy to provide a basis for any but the most trivial aspects of psycholinguistics. in consequence there was a growing enthusiasm for the investigation of generative grammars and the complementary idea of species-specific biological bases for the deep structures which underlie complex aspects of perception, memory and cognition. this shift in paradigm was contemporary with a similar refocusing of interest in anthropology, which was part of a wider shift towards an approach which had become known as structuralism. those within the orbit of Anglo-Saxon empiricism were in general more resistant to this new way of thinking, but the influence was notable nevertheless.

my second point is merely a simple observation, but one whose genuineness is unproblematic in informal discourse. in personal terms, I have often noticed myself in quite casual conversation confusing the names of two former partners. to me this is evidence (admittedly only one tiny piece of a very large jigsaw) for the existence of a deep-structure corresponding to the social category of significant other. this, if it exists, is completely distinct from any kind of specific memory of individuals one has related to. of course the hard-core empiricist would still be obliged to insist this was "merely" a type of misremembering. but such a dogmatic approach ignores the insights which have long been available through the informal paradigm which underlies Freud's methodology in The Psychopathology of Everyday Life and also perhaps Jokes and the Subconscious - the general hypothesis that minor errors or distortions on the accessible surface of behaviour can offer valuable clues about the deeper mental processes which underlie the surface behaviour and play a key part in its production, but which are far less accessible to introspection. a very good example which clarifies this particular distinction is the tip-of-the-tongue phenomenon where we "know what we want to say" but just "can't find the word". often the sought-after word spontaneously arises in consciousness some time afterwards. i.e. the search, once initated, continues at the preconscious level, and this process continues to run - in the background, as it were, to use computer parlance - even though the conversation is long finished. have you ever rung a friend with some rather unimportant revelation of this type - "I've just remembered the word I couldn't recall" - only to find that the relevant context has been entirely forgotten by them?


I have developed a self-regulation system that allows change at the physiological level. Does it have any merit? Please note: I do not hold a degree. This system is based on experience and self-testing.

I developed a self-regulation system that allows for the manipulation of sensations where they occur in the body. I'd love to get my idea out into the public, but was cautioned against potential liability. As such I am wondering whether this system has any scientific merit. Secondly, if the idea has merit, where do I start?

Overview

This system has two main applications: the immediate self-regulation of emotions, and the self-regulation of other bodily sensations, such as pain and other discomforts.

Emotions

We start with the assumption that the brain monitors the body for physiological changes (emotion), and then maps those changes to a specific emotion-related feeling, as noted by neurologist Antonio Damasio in this Scientific American article.

If we can call a specific set of physiological changes that form an emotion an emotional ‘profile’, then the system is used to interrupt one or more physiological features of the profile. This causes the profile to collapse and the emotion-related feeling to dissipate with immediate effect. It is achieved using techniques (e.g. a body-internal micro action) inherent to the system.

In my experience this system does not rely on reasoning or any form of rationale, nor breathing techniques or meditation. It is non-intrusive and less susceptible to self-sabotage since the techniques are largely functional / mechanical in nature.

A further benefit of this system is that it allows for the generation of a general sense of positivity as well as specific positive emotions without requiring any specific internal or external stimuli.

Applications
I’ve used this system for the past five years to self-regulate emotions. These include run of the mill emotions, such as anger, despondency, sadness, and fear. It has also been used to successfully alleviate / eliminate the physiological features of stress, depression and anxiety. In all instances results are instantaneous.

Health

One accidental discovery associated with this system is its health applications. One aspect of the system is a functional or ‘mechanised’ positivity that can be applied anywhere in the body. When applied to pain or other bodily discomforts, the discomforts tend to lessen in intensity, or immediately vanish. I suspect that it also actively promotes the body’s natural healing ability where it is applied.

Applications

I have successfully used this system to address the following:

Random aches and pains
Inflammation
Wounds
Flu symptoms
Suspected nerve damage (Morton’s neuroma / metatarsalgia)
Rotator cuff damage
Pulled muscles
Stomach ailments

It should be noted that results in this instance range from immediate to the morning following application. Multiple applications are required with the more serious anomalies, however with marked improvement following each application.

I have also tested this system by allowing an anomaly to progress without any interference – specifically, instances of suspected nerve damage and inflammation. In most cases the discomfort only increased. A sudden application of the functional positivity resulted in alleviated discomfort and a U-turn towards healing.

I'm not going to answer the question I think you want answered: whether your system has merit. Instead, I'm going to answer a related question that I think you actually need answered: How do you determine if a therapeutic approach is effective?

Ultimately, this sort of question can only be answered with a clinical trial. In a clinical trial, your approach will be tested against other approaches or placebo approaches to look for differences in outcomes. In order to do a clinical trial, you need to get the permission of an appropriate regulatory body in order to enroll subjects and continue. Doing anything else is unethical.

In order to get this permission, you need some credibility in the field. For this sort of project, that would probably start with either having some sort of degree or certification as a clinical psychologist or therapist, or recruiting people with those credentials to help you with your study. If you don't think your idea is worth this effort, your idea is not worthwhile.

On the way to getting this education, you will learn about existing strategies that are used, which will help you to refine and consider your own terminology. Maybe you think you've invented something new but find that it already exists under a term you didn't know. Maybe you find someone else has already studied something similar and found no effect. Maybe you find that your idea is really a novel improvement to something already used in practice. Learning these things will help you to frame your idea. If you don't think your idea is worth this effort, your idea is not worthwhile.

If you want to go in more depth along this way of thinking, the next step would be a research degree, most likely a PhD. The training for a PhD will teach you how to approach these ideas scientifically, to look through the literature, and just generally to go deeper into a topic than you would in a clinical position.

Note that there are many many many people that go down this path and put a lot of effort into their work: there aren't really any easy answers left. It's a lot of work to find positive results. You probably won't start researching your own ideas, but rather expanding incrementally on the work of others. At that point, you will have enough credibility and background knowledge to test new hypotheses. You might find that your original thinking makes no sense. You might find new motivations by reading about other peoples' work (and 'standing on the shoulders of giants'). If you don't think your idea is worth this effort, your idea is not worthwhile.


Prevalence of mental health problems in medical professionals caused by exposure to death? Some medical professionals work in areas where they are exposed to death often (say, E.R, O.R, Cancer Treatment, etc.), specifically in an area where they bond with the patient and the patients' families over a long period of time, such as cancer treatment.

Does such exposure sometimes cause psycopathic/sociopathic behavior, shizophrenia, apathy, and other mental and emotional scarring?
Does such exposure cause changes to thoughts on death significantly?
In an attempt to numb this pain, would the subjects be more likely to believe excessively and obsessively in religion and the afterlife? (Please don't take offense if you are religious.)

Of course I'm not saying that all subjects in this situation would display these symptoms, but depending on pre-existing conditions I wonder whether some are more susceptible to emotional trauma than others.

I believe, and I do not know if good quality epidemiological evidence exists, that such situations may trigger abnormal illness representations among medical professionals. Factitious disorders, for instance, I believe could be some way to deflect depression in some individuals. Along with abnormal illness representations could also come abnormal moral representations of illness, which, if not outright religious, links in somewhat with the notion of salvation.

Studies concerning abnormal illness representations are usually concerned with patient's illness representations. I see no epidemiological studies or data concerning the illness representations of medical staff, would be medical staff, or former medical staff (for instance, those who quit after traumatic experiences with patients) when they present as patients. Indeed, calling into question the illness representations of medical staff is not exactly politically correct. It's even a rather effective way to get you labelled as psychotic in some flavour or another.

However, from a clinical perspective, (i.e. with a clinical bias) a risk factor for factitious disorder is when someone has or has had a professional wish of working in the health care field. Such as a medical doctor who went into depression after a patient died and who did not fully get over it...

I'd love to know what data there really is out there to back up this clinical claim. Best I could find is Lois Krahn's work at Mayo Clinic:

https://www.ncbi.nlm.nih.gov/pubmed/12777276

To me, this is an extreme manifestation of more common mental issues affecting medical professionals.


What are other methods to induce ego depletion besides using emotional videos and thought suppression? Muraven and Baumeister (2000) proposed that self-control is a limited resource akin to strength or a muscle, to deplete this limited resource leads to subsequent self-regulatory failure. Ego depletion, the temporary depletion of self-regulatory capacity by an initial act of self-control, has a significant effect in decreasing performance in self-control tasks (Hagger et.al, 2010).

I would like to know the methods to induce ego depletion, so far I only come across studies using emotional videos and thought suppression (Baumeister et.al., 2003) to achieve this cognitive process.

Baumeister, R. F. (2003). Ego depletion and self‐regulation failure: A resource model of self‐control. Alcoholism: Clinical and Experimental Research, 27(2), 281-284.
DOI: 10.1097/01.ALC.0000060879.61384.A4
Hagger, M. S., Wood, C., Stiff, C., & Chatzisarantis, N. L. (2010). Ego depletion and the strength model of self-control: a meta-analysis. Psychological bulletin, 136(4), 495. http://dx.doi.org/10.1037/a0019486
Muraven, M., & Baumeister, R. F. (2000). Self-regulation and depletion of limited resources: Does self-control resemble a muscle?. Psychological bulletin, 126(2), 247. http://dx.doi.org/10.1037/0033-2909.126.2.247

In the supplemental materials (Appendix A) of the meta-analysis by Hagger et al. (2010), you can find a comprehensive taxonomy of different methods that have been used to induce ego depletion. As the table summarizes a great variety of different paradigms, I will only list a few examples of methods and papers here. The references can be found in this document.

Hagger et al. sort the methods into 3 "task spheres" depending on whether they focus more on affective or cognitive processes:

Affective

controlling emotions - for example reading book passage aloud in emotionally expressive fashion (Gailliot, Schmeichel, & Maner, 2007, Study 1), regulating negative affect when describing a situation (Bruyneel et al., 2009, Studies 3 & 4)
controlling impulses - for example crossing-out-letters task (e.g., Baumeister et al., 1998, Study 4), modified Stroop task performance (e.g., Bray, Ginis, Hicks, & Woodgate, 2008), Appetizing/unappetizing food taste perception task (e.g., Baumeister et al., 1998, Study 1)

Cognitive

controlling attention - for example focusing attention on subject and not displayed words while watching a video (e.g., DeWall et al., 2008, Study 2), arithmetic task with/without auditory interference (e.g., Alberts, Martijn, Greb, Merckelbach, & de Vries, 2007, Study 2)
cognitive performance - for example paced forward (low fatigue)/backward (high fatigue) counting task (e.g., Wright et al., 2007), easy/difficult labyrinths task (e.g., Alberts et al., 2007)
controlling thoughts - for example suppressing thoughts of death (e.g., Gailliot, Baumeister et al., 2007, Study 8), suppressing thoughts of previously-viewed emotive video (Ostafin et al., 2008)
choice and volition - for example making product choices (Bruyneel, Dewitte, Vohs, & Warlop, 2006), forced-choice essay task (e.g., Baumeister et al., 1998, Study 2)

Affective and cognitive

social processing - for example, high-maintenance social interaction tasks (e.g., Finkel et al., 2006), other-race/same-race social interaction task (e.g., Richeson & Shelton, 2003)

References

Hagger, M. S., Wood, C., Stiff, C., & Chatzisarantis, N. L. D. (2010). Ego depletion and the strength model of self-control: A meta-analysis. Psychological Bulletin, 136, 495–525. doi:10.1037/a0019486