Are there any standard tests to measure psychopathy? While looking into another question on how to measure the adoption of norms, I came to wonder whether there are any standard tests to measure psychopathy.

What are the accepted standard tests to measure psychopathy?

The Hare Psychopathology Checklist is considered the current gold standard for measuring potential psychopathy. If you're interested in psychopathology, the book Without Conscience by Robert Hare, Ph.D., is a fascinating read. He has a second book called Snakes In Suits, which I have not yet read, so I cannot recommend or not recommend it. Dr. Hare has a website with a lot of fascinating information and links about psychopathy.

Anyhow, the Hare Psychopathology Checklist is abbreviated as the PCL. There is the regular PCL (First Edition), the PCL-SV (Screening Version), the PCL-R (Second Edition - Revised - Adults), and the PCL-YV (Youth Version). Only a clinical professional specifically trained in administration of the PCL or PCL-R can give an accurate assessment and interpret the results. When I was working with offenders, I sent exactly three individuals to have a PCL-R assessment and all three times the offender came back as having exceptionally high psychopathy scores. When you work with offenders you learn what the psychopathy vibe feels like.

The primary purpose of the PCL, any version, is to determine if psychopathy is present. There is no perfect test to predict recidivism in any population; there are simply risk factors that, when combined together, demonstrate a lesser or higher presumption of risk for recidivism, and risk is dynamic (see below). If I may quote from the Colorado Department of Safety, Division of Criminal Justice, Sex Offender Management Board, as I did in my answer regarding pedophilia, I think this sums up recidivism in psychopaths quite nicely:

Risk is dynamic. Treatment and supervision systems must be flexible enough to impose greater external interventions during periods of high risk and reduce interventions as offenders internalize and demonstrate risk management skills.
The presence of certain character or personality disorders is a risk factor for sexual re-offense. Mental health science has no identified cure for personality disorders. As a result, long-term treatment and supervision may benefit adult sex offenders with
personality or character disorders to maintain changes and refrain from sexual re-offense.
Prediction of the risk of re-offense for sex offenders is in the early stages of development. Therefore, it is difficult to predict the likelihood of re-offense or future victim selection.

John Pick listed the Levenson Self-Report Psychopathy Scale in his answer.

When working with offenders, we administered a self-answered test called the ASUS, which addresses risk factors. As well, we administered the Level of Supervision Inventory (LSI) which also looks for risk factors in offenders on community supervision (I'm being vague here because both the ASUS and the LSI are copyrighted material).

There are hundreds of articles on psychopathy and a variety of topics. The website HALO works with law enforcement in topics in forensic psychology, including psychopathology.


What causes fetishes? Are they sexual disorders? Why do people have fetishes,  such as foot fetishes?
How do such fetishes form?
Are childhood incidents the main cause of fetishes?
Are fetishes a sexual disorder?

Having one or more fetishes is very widespread, and thus rather normal.

  The prevalence of fetishism is not known with certainty.[21] The
  majority of fetishists are male.[21] In a 2011 study, 30% of men
  reported fetishistic fantasies, and 24.5% had engaged in fetishistic
  acts. Of those reporting fantasies, 45% said the fetish was intensely
  sexually arousing.[23] In a 2014 study, 26.3% of women and 27.8% of
  men acknowledged any fantasies about "having sex with a fetish or
  non-sexual object".
  https://en.wikipedia.org/wiki/Sexual_fetishism

A disorder is per definiton something abnormal

  disorder [dis-or´der] a derangement or abnormality of function;
  http://medical-dictionary.thefreedictionary.com/disorder

So the answer to your question would per definition be: No. Having fetishes is normal and not a disorder.


Why do people suddenly look back if you look at them for a while? You possibly are familiar with the following situation, I do not know if this is a researched phenomena or not however.

You look straight at somebody for some time and suddenly, even though he or she does not consciously know that you are looking at him or her, he or she suddenly starts to look back at you.

I am wondering why and how this is happening?

How are people unconsciously recognizing other people looking at them and what makes them look back to them?

What you describe is an illusion.

(a) The human field of view is almost 180° when staring straight ahead and 270° with eyeball rotation (looking to the side without turning your head).
If you look at someone from slightly behind and to the side, they will appear to be gazing forward, and you may feel unnoticed, but in fact you are within their field of view.

(b) The peripheral field of view is highly sensitive to motion. So if you turn your head towards someone while you are within their peripheral vision, their attention will automatically focus on this (danger! predator!) stimulus and they will turn their head to you. This is a reflex.

(c) On the bus or subway, if someone sits in your field of vision, they will have noticed you when you or they came in and therefore know you are there. If you both are in a public place, they might not have seen you arrive, but they will know that someone might have. Self-conscious people feel observed, and they continually check if someone watches them, who it is, and how they react. Now if you look in the general direction of a self-conscious person, and this person looks around like they do every few seconds, this movement will cause you to look at them in reflex, giving them the impression that you have been staring at them all along. If both of you stay in the same place for some time and they continually check on you, and their movement makes you look up almost every time, they will feel like you are watching them all the time, although you are focused on something else and only react to them looking at you.

(d) Please also look at Eoin's great answer explaining illusory correlation.


Are there synapses on other neuron terminals in human brain like in Aplysia I am referring to Eric Kandel and his experiment on Aplysia where he shows that synapses between a pair of neurons can be modulated by means of a third neuron that synapses onto the terminals of the two other neurons. The third neuron doesn't cause post-synaptic firing, but it modulates the activity and strength of the synapse.
This is known as modulatory input-dependent plasticity as depicted in the following pictures. For more information you can refer to this
My question is whether such synapses exist in the human brain too? If yes, are they abundant, or they are rare in the human brain, and what is their duty in brain?

A bunch of papers I was able to dig up after a cursory search on Google Scholar strongly indicates that heterosynaptic modulation does exist in man, at least in the motor cortex. In these papers the conclusion was reached by using indirect measures, namely by making use of specific stimulation strategies in intact brains in living humans. This as opposed to methods that more directly approach the question, like histology, or single-cell recordings.
References
- Hartwig et al., J Neurosci (2004); 24(13): 3379–85
- Jung & Ziemann, J Neurosci (2009); 29(17): 5597–604
- Nitsche et al., J Neurosci (2007); 27(14): 3807–12
- Zhen et al, J Neurosci (2014); 34(21): 7314–21


Models of a working (short-term) memory task that combine performance and reaction time? I am looking for the advice regarding the modelling of the results of a working (short-term) memory test. In a typical case, performance in such tests can be characterized using the hit rate and false alarm rate, which can be nicely combined into d-prime, and the reaction time. My question is whether there are smart concepts how all these parameters may be fused together to generate some sort of the "working memory performance index"? (Toy example: d-prime that is weighted by the log-transformed reaction time.) Any references will be very much appreciated.

Upd: I am interesting in the specific application and possible specific pitfalls for the working memory research.

This is a tough question, one that I have had to face in my own research. Your question has already been answered/addressed in How to analyze reaction times and accuracy together?

In short, there is no universal method. If you don't find the references or methods listed in that question useful, then I suggest you will require a computational model such as the Linear Ballistic Accumulator. The LBA is a (structurally and computationally) framework that informs process underling both RT and error data (drift rate vs response criterion).


Why do we have so many wishes and desires? Two years ago I started to learn (as self-education) evolution theory and neurobiology
for to understand - who we are and where we came from?
Now I see clearly that we are our brains, which are the result of RNA & DNA selection
and replication.

Many of the issues now resolved for me: about love and intuition, origin of religion and art etc.

But one question remains "a mystery":
why are there so many wishes, desires, urges?
What is the neurobiology base for a monstrous amount of consumer goods, objects of art etc.?

The most primitive idea is "complexity of brain -> intricacy of processes -> lots of desires".
Another naive answer has to do with so called "play-explore-investigation instinct",
which plays an important role when two basic instincts are "still".

But to me, human wishes and urges look like more of a  Akkerman function
than just "a lot of".

I belive that (sooner or later) evolution and neuroscience will give answers to all questions
about our mind and behavior.
So glad to hear something about this one!

In the context of evolution, desires and dreams (beyond the lower tier of Maslow's Hierarchy) could be seen as, not an adaptation, but a spandrel of the adaptation of consciousness.

Consciousness allows us higher cognitive skills, particularly the ability to reflect on events and predict events through modelling, which allows us to modify our behavior in a succesful way.   But this extra predictive power also gives us an imagination with which we can imagine ourselves in a better position to exploit our dopamine centers (seek pleasurable activities that don't propagate the species).


Do psychiatrists have educational requirements other than an MD? Most pre-medical students take psychology, biology, chemistry or something science-related, in addition to the classes needed as prerequisites for medical school, for their undergraduate degree or even for a master's, but is there any particular degree besides an MD that someone who wants to be a psychiatrist needs to take?

For example, is a business, philosophy, english or political science major who has taken the required classes of medical school who later finishes medical school eligible to train to become a psychiatrist? I'm curious as to how such a person would get the psychology-related training and knowledge. Is it in the training after medical school? Is it related to medical school electives?

The only required degree to become a psychiatrist is a doctoral degree (M.D.). Using your example, yes those people could train to become psychiatrists.

After passing the Medical College Admission Test (MCAT) and going through med school, most students undergo a psychiatric residency (aka. clerkship) where they are trained in different medical centers (hospitals, health clinics, psychiatric wards, etc.). This allows the prospective psychiatrist to gain "real world" experience. After a psychiatric residency, psychiatrists must then take an exam issued by the American Board of Psychiatry and Neurology. If they pass this exam they are certified and can then legally practice as a psychiatrist.

Source:  http://study.com/articles/Psychiatrist_Educational_Requirements_for_Psychiatrists.html

Edit: Med school teaches you theoretical psychiatric knowledge whereas the clerkship will teach you how to apply it. The clerkship could also train you in specialty fields.


Group differences reflecting different use of a rating scale vs actual difference in perception I was reading a paper that reports average ratings of chords by two different groups of subjects (trained musicians, and non-musicians).

The paper makes the argument that "These group differences may reflect either the manner in which the two groups of subjects used the rating scale or in their perceptions of the chords."

Obviously, one would hope that the latter is the case rather than the former, although from this graph one can't be sure since error bars, which would be very informative in this case, are not shown. My question is: is it correct to say that the answer to this question can be given if one compares the variances across groups, e.g.with Levine's test? And that, if found to be unequal, one can argue that the group difference reflects an artefact, i.e. a difference in the way the two groups of subjects used the rating scale?

I indeed think that it is not possible to conclude that the scales are used differently, based on variance alone. Normally one would assume the scale is used properly and the effect you see is indeed the result of (not) having a trained ear.

There do exist ways to investigate how one uses a subjective scale. In a paper I presented, we looked at how people interpreted a subjective workload scale. This scale contained verbal descriptors that conveyed a particular amount of workload, and this amount was estimated by the participants. This scale was designed to be linear and cover workload from "no workload" to "work too demanding". Therefore, we would expect a linear line that starts at 0 (no workload) to 150 (complete overload; we used 150 instead of 100). The results indeed confirmed this and the groups perceived the items on the scale similarly.

So far, the method is kind of similar to your paper. The difference is that we gave the participants anchor-points to help them rate the items: The zero-point (no workload) and the 150-point (complete overload). This way the participants had the same reference points, which should enable them to use the entire range, regardless of their experience or something.

You could also use these anchor points to see how consonance ratings differ. Let them listen to a perfect dissonant and a perfect consonant tone and say they are rated zero and ten respectively (or something like that). If the two groupsc rate the sounds similarly now, they have probably interpreted the scale differently before. However, if you still find the same difference as before, it may suggests that untrained musicians can indeed not distinguish the sound very well (and the scale was interpreted properly before).


Are there specific neurotransmitters for specific sensations? Nerves can detect pressure, temperature, light (eyes), sound, friction- at least. Does each sensation have its own neurotransmitter?

I'm only a little familiar with neurotransmitters. This page pretty well sums up what I know about neurotransmitters.

So it seems like its a combination of neurotransmitters that flow from any single perception area.

There are neurotransmitters that are associated with specific functions within a neural circuit, but I would not associate a specific neurotransmitter with a specific sensation. There is also more complexity to this, because there is a plenty of receptors for each neurotransmitter. These receptors have slightly different properties, which may influence the effect on the post-synaptic neuron and consequently the percept.
Another concept is the effect of neuromodulators that regulate larger areas of the brain, e.g. noradrenaline, or serotonin. These have broad effects that change the brain state and are associated with a certain 'feeling'. For example, release of noradrenaline would lead to higher ventilation, higher heart rate, sweating etc.


Is there any evidence to support a correlation between how much bodily energy you are using, and how quickly time appears to pass? It seems to me that time passes more slowly when I am drinking coffee, but when I stop, or I am tired it seems that time passes a lot faster.

Could this have something to do with the sampling rate at which the life-loop in my brain can perceive things?  Since a higher sampling rate in this life-loop would cause more time to be perceived?

There's literature on temporal expansion with vigilance.  Perhaps this might get you started.

Tse, P. U., Intriligator, J., Rivest, J., and Cavanagh, P. (2004). Attention and the subjective expansion of time. Perception & Psychophysics, 66(7):1171–1189.

In this instance they're looking at how odd, unique, or surprising events might increase the amount of attention applied and that those events seem to last longer than othewise very comparable ones.  The literature reviews speaks a bit to what you've asked about.


How useful are neural circuits in psychology? We can identify many kinds of patterns of how neurons connect such as lateral inhibition, negative/positive feedback, convergence, divergence, and facilitation. But have any of these circuits been used to make claims about how a cognitive or psychological phenomena is computed? Is that even possible, given its complexity? In which context is neural circuitry useful?

Contrary to one of the other answers, I will have to respectfully disagree. Neural circuity is both the pinnacle and future of cognitive neuroscience. We already know the large areas of the brain are associated with specific cognitive processes, for example the NAc shell is associated with desire to seek out motivational objects such as food, but this could just as easily facilitate gaming, dancing or sex. The problem comes with investigating these behaviours in humans. We can easily test circuits on animals, but humans are far more difficult as we can only use scanning equipment like EEG and fMRI. While scanning equipment has improved the spatial or temporal resolution makes studying these circuits in humans difficult. However animal research supplements this and can show us circuits that are involved in particular cognitions, while the patterns of neural firing tell indicate particular activity. For instance we know the visual pathways in great detail how light engages neural activity in the retina, and how this information is transmitted to the occipital cortex to create a representation spread across the neural activity of the occipital cortex. In fact we understand this so well now that cognitive neuroscientists can take an EEG recording of activity while you sleep and interpret the neural activity into an image under specific circumstances. This fascinating method is called neural decoding, and it was developed out from our understanding of neural patterns of activity and mapping of neural networks developed over decades. Of course the same neural activity can be used to map networks and model neural activity in computational models which mimic cognitive processes.

Of course this is easier for vision, hearing and somatic perception as these are straightforward cognitive processes which are generating virtual representations of the world we experience. What is far more difficult to assess are the memories and experiences that are recalled and how these influence decision making relative to the environment you find yourself in. However this is all being investigated, research starts with large neural structures like the NAc shell and then moves down to more specific areas followed by the circuits connecting it to other parts of the brain relative to particular cognitions. An example may help, motivation like hunger drives you to eat this is used by both information coming from your environment and internal changes. For instance once food has been consumed our brains assess the value of the food, did we like it? was the food more or less pleasurable than last time? did it make us happy? This activates the pACC, PAG, OCC, lOFC, rACC. The areas mentioned largely deal with attention, affective assessment (feelings), and pleasure. The activation of these areas helps an individual to make future decisions about consuming food. In rats the order of area activation is well understood, in humans there is still work to be done. But overall the fundamental mechanisms are the same, and can be modelled computationally. Understanding how the fundamental structures and there activity in context for both people and animals is essential in understanding disorders ranging from schizophrenia to obesity, and helps other researchers to develop assessments and interventions, such as drugs or government legislation. Or for companies to taylor their products to their consumers needs. Crucially, to the question at least, this information can be used to predict behaviour, in fact that basically the role of any computational model.

Fundamentally our hard wiring is relatively similar, it is this that we investigate, and it is these hard wired mechanisms that have the greatest impact on our behaviour and cognition.  Cognitive scientists use the activation patterns of neutrons as a means of mapping these cognitive processes in neural circuitry. Finally I will say that overall the brain isn't really so complicated, its quiet simple really if you consider it from an evolutionary perspective. We and all other animals have developed by means of natural selection to survive long enough to pass on our genes, both our behaviour and neural development demonstrate this. The extra complications in behaviour are merely complexities that enhance gene survival, until they are lost or supersede within the same selection process.


What happens if you lie to a child during language acquisition? During language acquisition a child can learn 20 words a day. What would happen if the parent decided to lie to the child during this time so that whenever the child said "what that?" the parent made up a random word.

Would this permanently stay in the child's mind forever? Or would the child just learn the "real" word from everyday speech?

As an aside, for years I thought the word "modest" meant the opposite of what it means. Because it is only ever said sarcastically. As in "wow, your sooooo modest!" And that's just one word.

You would need a conspiracy of many people to prank a child with this kind of thing, because kids are really good at tracking the information value of sources. If you give a different random word every time they'll discount you as an information source, if you give the same random word every time they'll learn it... and use it only with you (more or less, but increasingly so with age/experience.) See Birch et al. (2008) for more details.

You might also have fun with the literature on early bilingualism, which is basically this situation, right? Kids are phenomenal at this. See for example Liberman et al. (2017).

Birch, S. A., Vauthier, S. A., & Bloom, P. (2008). [Three-and four-year-olds spontaneously use others’ past performance to guide their learning.][] Cognition, 107(3), 1018-1034.
Liberman, Z., Woodward, A. L., Keysar, B., & Kinzler, K. D. (2017). Exposure to multiple languages enhances communication skills in infancy. Developmental science, 20(1), e12420.


What is the scientific term or concept for inner thought control? Usually when a thought arises, it seems that we quickly scurry after it, unconsciously getting caught up with whatever everyday thoughts come up. These can be invoked internally or externally.
(No reference to that phenomenon but for example, you may have just read that and add more thoughts or complicated it. )

What is the scientific term or concept that explains being able to NOT follow and run after every thought that arises out of the brain or not be swayed by them in anyway?

Your question touches on a number of different active research areas in cognitive science and cognitive neuroscience.

The motoric component to not "following and running after every thought" is commonly understood to reflect a capacity for response inhibition - that is, the ability to override or cancel ongoing or prepotent motor commands.  This process is thought by some to be similar to that involved in reducing perceptual or cognitive interference, for example in attending to a particular type of information despite salient or prepotent sources of distraction (e.g., as studied in the Stroop and Flanker tasks), or in reducing interference from recently abandoned information/goals (e.g., variously studied in terms of negative priming and lag-2 repetition cost respectively).

However, there are other perspectives.  One is that the ability to maintain an overall task set - perhaps a more stable one, that has a hierarchical influence over other more transient thoughts/perceptions - might be responsible for keeping these kinds of more extraneous exogenous and endogenous distractions at bay, through a process known as competitive lateral inhibition.  Keywords for this kind of work include biased competition, goal maintenance, context maintenance, and active maintenance.

Finally, there is a third line of work relevant to your question, in which cognitive processes are selectively granted control over behavior.  This has so far been studied primarily in the domain of visual search, although computational models suggest that it may have rather domain-general applications.  In the visual search literature relevant keywords are "accessory items in working memory". In the modeling literature, this is known as an "output gate."


psychologically , which color for which lesson? Imagine I have an educational website which hosts high school students and presents lessons like chemistry, physics, mathematics, etc. Now I want to give each one of my lessons a unique color. I thought maybe there is a psychological thing about this. Is there? If so, could any one give such resource that tells me what color is suitable for chemistry and so on.

I haven't ever seen material which describes links between colors and some knowledge fields. To my mind, it depends on your own experience. But there are a lot of material about common feelings of different colors, that could be helpful for design, for organization of any kind of information. Look here and here.


What is the term for learning to group objects I've been googling this for a few days now but haven't come across what I'm looking for.

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

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

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

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

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

...

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


Visual field testing: Choose between Yes/No, 2AFC, and 2IFC task? As a newbie to psychophysics experiment, I have a small project to do visual field testing on healthy, adult, naive subjects. The experiment stimulus is a small sine grating (0.3 degree, 6 cycles/degree) embedded in one of 25 possible locations in a noise background picture (18 degree). The orientation of the grating, and the contrast of background noise is fixed, and I need to measure the sensitivity (d') at 25 locations given a series of (probably 3) grating contrasts, and a series of stimulus exposure time (50,100,200,300,400 ms).

In a single trial, subject knows where the grating will be located, and maintains fixation at the center of noise background. Then the stimulus will be briefly presented (once in Yes/No and 2AFC, twice in 2IFC) for one of the stimulus exposure time, and subject need to judge whether the grating is present (Yes/No), or is located in which stimulus (2IFC and 2AFC). For a each unique combination of grating location, grating contrast and stimulus exposure time, I plan to do 16-20 repetitions to measure d'. So there are LOTS of trials.

I think this should be a mature experiment, but I am stuck on choosing between the following 3 experiment paradigms. The major problem is the time required to complete the experiment. I have run pilot experiments on all of them.

1-interval yes/no task. This task runs fast, but suffers from changing response bias. Is the response bias going to negatively affect d'? In signal detection theory, d' is insensitive to bias only when the variance of response to signal and signal+noise is equal. However, I don't know whether there is firm experimental evidence to support this.
2AFC task. This task comes from a suggestion in textbook. Instead of presenting one cue of target location on each trial, I can present two cues that is symmetric around fixation point, and subject need to judge which cue location has the grating. The task assumes that human visibility map is central symmetric, and effectively cut the number of locations to half, so it runs even faster than the Yes/No task. However, it is rarely used in literature about visual field testing, what might be the potential drawback?
2IFC task. I see many literatures doing this, but it is the slowest one (more than double of the time for Yes/No). What's worse, because the stimulus is brief presented, and the interval between them is short (400 ms), sometimes subjects report that they "see the stimulus but forget which interval has it". So in some of our pilot data, the sensitivity at fovea is lower than in near-peripheral, because subjects had made an error. How do psychophysical researchers overcome the problem of subject error, and the problem of long, boring experiment?

Thanks for any help.

I am unsure as to the exact purpose of your experiment; the title seems to point toward a visual field test, whereas the question body seems to point to a visual acuity (VA) test? Are you interested in testing grating VA across the visual field? In the latter case, a subject needs to focus on a particular point and visual scanning is absolutely forbidden. The VA will be determined according to the last visible grating across a number of visual angles.

On way or the other, I think you answered your question yourself.

A yes/no task is prone to bias, as the threshold to say 'yes' may change over time. It's also prone to investigator influence, as the % false-positive rate (which you should keep track of online) may exceed a certain threshold (often set at 25%). At that point the researcher should intervene and tell the subject to elevate their threshold, after which the data are likely substantially different from previous trials. However, it's fast, as only one stimulus per trial is needed.

I have personally always used serial 2AFC tests. A subject definitely needs time to do the test. As you say yourself, 400 ms inter-stimulus time is simply too short. I think I would opt for a presentation time of a few seconds, a downtime of at least a second, and then the second stimulus.

The problem with the simultaneous 2AFC task is one of definition - if one stimulus is the target, then the other one is the no-stimulus. If they are up simultaneously, then isn't this identical to the yes/no task? The subject either perceives a grating, or not (yes/no). As wikipedia states:

  Two-alternative forced choice (2AFC) is a method [where] the subject is presented with two alternative options, only one of which contains the target stimulus, and is forced to choose which one was the correct option.

A true 2AFC task is thus when they need to choose between A or B. That's only possible when doing it serially in your case as far as I can see, as a simultaneous task can basically be reduced to a yes/no task (they see the grating, or they don't).


How much pleasure can brain endure? As of 2018, is it possible to induce pleasure in humans by some intervention like sending electrical signals? I've read that it's been done on mice. If not, it's quite imaginable that it will become possible in the near future. What would be the neurological implications of such intervention, other than addiction? I mean what would happen to the brain if we force the brain to stay in an orgasm-like or ecstasy state for several minutes? What are the possible adverse effects or damages? Of course that we know very little yet, but I appreciate to get some insights on how pleasure works, and if there really are pleasure centers in the brain that can be easily manipulated.

As of 2018, is it possible to induce pleasure in humans by some intervention like sending electrical signals?

Yes, it is possible and has been done, typically as DBS (Deep Brain Stimulation) for various disorders: OCD and depression are a few examples where the brain are stimulated induced pleasure. (Synofzik, Schlaepfer & Fins 2012)

Regarding "How much"... How much until what? Death? Brain damage? Subjective "that's enough"? Habituation? Realize that most of what you ask is definitely unethical as an experiment (on humans, which is your focus) in this century.

For an ethics discussion I stronly suggest the aforementiond paper paper by Synofzik, Schlaepfer & Fins "How Happy Is Too Happy? Euphoria, Neuroethics, and Deep Brain Stimulation of the Nucleus Accumbens" which has been the subject of interest for popsci press (e.g. article in The Atlantic).

A few points paraphrased from the paper:

the euphoria was a result of deep brain stimulation (DBS) treatment for OCD (obsessive-compulsive disorder) performed in the anterior
limb of the internal capsule and the nucleus accumbens region (ALIC-NA).
The pleasure experienced is voltage dependant. However, patients also reported being overstimulated when the voltage was too high and expressed that as some kind of discomfort either somewhat physical "that's too much", or more psychological concern such as that they felt "unrealistically good”.
Habituation to the pleasure elicited by this type of DBS reportedly does occur, and pretty quickly, on the order of minutes. This is somewhat surprising given that they also mention the classic experiment of Olds (1958), in which mice kept engaging thousands of times in behavior that rewarded them with brief shocks to the brain's "pleasure center". I'm guessing there's something either in the biology or in the protocol that causes faster habituation in humans, but the paper is not clear on what that is.


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

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

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

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

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


Is there a correlation between schemas and social constructs? While studying Piaget's stages of cognitive development in Educational Psychology, the textbook talks about Piaget using the idea of "schemas" which are mental representations or ideas about what things are and how we deal with them.

I also stumbled upon the theory of social constructionism.  While learning psychology, should I look at these as a correlation or two separate entities?  Also in the field of psychology, does one theory have precedence over another?

Yes the two theories are related, but the theories come from two different fields, cogintive science and sociology. First the definitions :

  In psychology and cognitive science, a schema (plural schemata or
  schemas) describes a pattern of thought or behavior that organizes
  categories of information and the relationships among them

.

  Social constructionism or the social construction of reality
  (also social concept) is a theory of knowledge in sociology and
  communication theory that examines the development of jointly
  constructed understandings of the world that form the basis for shared
  assumptions about reality

The social construct is the jointly constructed understanding of many individuals. The understanding of one individual is stored as a schema.


Could a painful stimulus be effectively used as a learning aid? In rats, the application of a painful stimulus has shown an increase in overall arousal and the ability to learn certain behaviours (The study is neatly summed up in this video: Motivation and Reward in Learning). The experiment with electric shocks is shown on the second half.

It is common sense that human beings would naturally avoid painful consequences, but the deliberate application of a noxious stimulus may also elicit a unconscious response, or conditioning, to avoid those behaviours, which would mean a faster learning rate.

Learning could also be improved because pain is an intrinsically meaningful response, while perceived failure is somewhat weaker and less imediate as a motivating agent.

Could small electric shocks, applied by another individual, or a computer program (maybe even self-administered), have any use in learning? At what specific tasks would this technique be more effective?

Claparede's Pinprick Experiment

From http://www.fearexhibit.org/brain/memory/claparedes_pinprick_experiment:

  In 1911, a French doctor named Edouard Claparede published his
  observations of an amnesiac patient. Despite repeated interactions
  with the woman, sometimes only minutes apart, Claparede had to
  reintroduce himself every time he reentered the room; the patient
  never recognized him as someone she'd met.

  During one of their "introductions," Claparede hid a tack in his palm
  and pricked the patient when they shook hands. The next time they
  "met," the patient refused to shake Claparede's hand though she
  couldn't explain why since she did not recall ever having met the
  doctor.

  Today, scientists interpret the patient's reaction as proof that
  multiple memory systems are at work within the normal human brain. A
  subconscious memory system in the woman's brain had formed an
  association between shaking Claparede's hand and a painful experience.
  Therefore, despite the dysfunctional state of the memory system that
  would have normally enabled the patient to consciously remember the
  event, another memory system was still working, trying to keep her
  safe from harm.

  A century ago, Claparede's observations were not readily understood as
  such evidence for multiple memory systems. We owe much of our
  knowledge about the brain and memory to studies of animals. Without
  these examinations, scientists might never have properly interpreted
  such observations of human subjects.


What is the distribution of performance in academic programming subjects? On Programmers SE there is a popular question about scientific evidence for whether some people either are or are not able to program.

One person cites an unpublished manuscript by Dehnadi and Bornat (2006) who state in an abstract:

  All teachers of programming find that their results display a 'double
  hump'. It is as if there are two populations: those who can, and those
  who cannot, each with its own independent bell curve.

That said, educators have choice in how individual assessments are scored, how assessments are combined, and whether and how any final scores are scaled. These could all influence the shape of the final grade distribution.

I also imagine that to get a double hump would suggest that the variables that best predict student performance (e.g., time spent on subject, general ability, subject-specific ability) would have to either show a double hump or show a discontinuous relationship with performance. In particular, I can see that students that drop out of a subject without formally un-enrolling are likely to fail very badly and appear in a separate hump. I also suspect that certain types of subjects where answers are clearly correct or incorrect and where intuition from everyday life is less directly relevant may also give rise to a process where it appears as if people can either do the subject or they can't.

Questions

What is the distribution of grades in university subjects?
To what extent does the distribution of grades in programming subjects differ from non-programming subjects? Is it bimodal?
Is there any theories or empirical evidence about what leads to bimodal grade distributions?

References

Dehnadi, S. & Bornat, R. (2006). The camel has two humps (working title). Middlesex University, UK. PDF and summary page.

Our university has a public grade distribution database, so I did a really quick analysis on some historical data to see if there was any support for this idea. To my surprise, it appears that there might be. But, my analysis is very limited.

I downloaded the grade distributions for all intro psychology and intro computer science classes from 2010-2014. This gave me the grades of about 15,000 psychology students and about 1,500 computer science students. I summed up the count for each letter grade, and then normalized to a percentage of students. Apologies for the somewhat ugly chart, but here's what I found:

The distribution for letter grades seems pretty consistent across both disciplines, but what jumps out to me is the assignment of "W" grades, which is the grade received when a student withdraws from the course after being enrolled for at least the first week of classes. About 20% of all intro CS students withdraw from the class, while less than 5% of intro psych students do. This might indicate that a larger number of CS students find the course to be too challenging for them, and withdraw rather than get a low grade.


Exercise for Mental health We do lot a physical exercise for keeping body in shape and strong. I have not heard about any exercise for mental health. Is there any thing like mental exercise or physical exercise also include mental exercise ?

There is enough evidence to tackle the issue of exercise and depression. I am not sure about the rest of the psychiatric spectrum and disorders. A 2013 review by Cooney et al found differences in the methodological rigor of the trials.

  For the 35 trials (1356 participants) comparing exercise with no treatment or a control intervention, the pooled SMD for the primary outcome of depression at the end of treatment was ‐0.62 (95% confidence interval (CI) ‐0.81 to ‐0.42), indicating a moderate clinical effect.

However, when they examined a smaller more methodologically rigorous group, the effect size lessened but was still significant.

  6 trials (464 participants) with adequate allocation concealment, intention‐to‐treat analysis and blinded outcome assessment, the pooled SMD for this outcome was not statistically significant (‐0.18, 95% CI ‐0.47 to 0.11). Pooled data from the eight trials (377 participants) providing long‐term follow‐up data on mood found a small effect in favour of exercise (SMD ‐0.33, 95% CI ‐0.63 to ‐0.03).

So yes, definitely exercise is very helpful for depression with meaningful improvements.

Reference:

Cooney  GM, Dwan  K, Greig  CA, Lawlor  DA, Rimer  J, Waugh  FR, McMurdo  M, Mead  GE. Exercise for depression. Cochrane Database of Systematic Reviews 2013, Issue 9. Art. No.: CD004366. DOI: 10.1002/14651858.CD004366.pub6.


How can humans tell when something diverges from the norm With this I mean the notion of humans being able to, for example, look at a painting and tell that something doesn't belong in there. For example sun glasses on the Mona Lisa, without prior knowledge of the painting. I just find it easier to spot or add things to something that are wrong than to add something that fits in perfectly.

I found some pointers to Gestalt Theory but I couldn't find anything there yet. I'll keep looking but maybe someone here knows what I'm trying to convey. Thanks.

The predictive coding model of brain function suggests that the entire function of the brain is to update an internal model of the world.

This process occurs by generating predictions based on the current model, and comparing these predictions to sensory information. The difference between the predictions and the actual information is the prediction error: this is the stuff that the brain has to work harder on, because it is these errors that require further action to update the models and make better predictions in the future.

Based on this model, unexpected things are highly salient, because they generate large prediction errors. In contrast, expected things are boring, and can mostly be ignored. This is a mechanism to filter the massive amount of sensory information we are capable of taking in at any given moment.

As of now, predictive coding is still just a model, and there is a lot of work being done towards finding evidence for predictive coding in the brain. That said, it explains the phenomenon you are describing fairly well.

Some references for further reading:

Bastos, A. M., Usrey, W. M., Adams, R. A., Mangun, G. R., Fries, P., & Friston, K. J. (2012). Canonical microcircuits for predictive coding. Neuron, 76(4), 695-711.

Kok, P., & de Lange, F. P. (2015). Predictive coding in sensory cortex. In An introduction to model-based cognitive neuroscience (pp. 221-244). Springer, New York, NY.

Melloni, L., van Leeuwen, S., Alink, A., & Müller, N. G. (2012). Interaction between bottom-up saliency and top-down control: how saliency maps are created in the human brain. Cerebral cortex, 22(12), 2943-2952.

Rao, R. P., & Ballard, D. H. (1999). Predictive coding in the visual cortex: a functional interpretation of some extra-classical receptive-field effects. Nature neuroscience, 2(1), 79-87.

Spratling, M. W. (2012). Predictive coding as a model of the V1 saliency map hypothesis. Neural Networks, 26, 7-28.

Yuille, A., & Kersten, D. (2006). Vision as Bayesian inference: analysis by synthesis?. Trends in cognitive sciences, 10(7), 301-308.


Why do we like expected surprises? The ambiguity effect says that we try to avoid uncertain outcomes. Still, many products are selling well excactly because they give uncertain outcomes. One example is Kinder Eggs, and many similar candies\toys. Some shops also get rid og their spare products by selling them in 'surprise bags'.

Why do people like buying products with uncertain outcomes, if the ambiguity effect is true?

There is no ambiguity as such with respect to expectations in those examples. When you buy a Kinder Egg, you know up front you won't know what's in there. In other words, it's perfectly unambiguous that you don't know what to expect from a Kinder Egg.


What causes an individual to not be able to hold all the details of a large project in memory? Background: First of all, I'm not in any kind related to cognitive science, I'm a programmer. I'm not even sure that it's the right place for asking my question, but I'll try anyway. So, first of all, I'll describe the initial problem that motivated me to ask this question. There are some concrete examples.

I join the programmers team that have rather big (but not huge) project. I'm trying to figure out how it works, how each part of the system cooperates with each other. I want to see how it works as a whole, so that I could say that I understand what's going on: what goes first, what goes next, without going into pretty much detail. I want to have this image in mind and to discuss the project with no need to diving into code, or to schemes describing the project, or any additional info. The thing that does not let me do this -- I fail to remember the system components, their execution precedence that may vary, and their interactions between each other.
I got explanations of some project use case. Everything seems to be clear, but there comes a time when I realize that I can not hold all this in my head, can not keep all precedence of actions, the interactions between them. The whole thing becomes blurry.

I tend to see these cases having the same reason. As this reason results in my wish for better results achievement, I call it a problem. It may or may not be a "problem" from medical or any other point of view, but this is a problem for me anyway. So, when I talk about solving this problem, I talk about improving my results in area described above.

Questions

What is this problem called where a person can not hold all the details of a large project in memory?
Is this a failure of memory?
Is the problem due to lack of intelligence?
Would any of the following reduce the problem: chess, poker, solving math problems, nootropics?

I just completed an extensive study (and corresponding lit review) of how people learn.  I think you are running into the classic difference between expert and novice users.

Experts vs Novices

It has been demonstrated that the knowledge structures in experts are different than those in novices.  In particular, experts' knowledge is far more structured, and they are capable of immediately connecting concepts that novices are unable to see.  (I have articles I can cite if you wish, but I'm just trying to get you on the right track here).

Bascially, people learn by slowly (or quickly) becoming "experts," that is, by organizing their conceptual models better around various concepts, such that the distinctions between them disappear into this web of schematic knowledge.

It has also been observed that novices remember learning "episodes" - e.g. hands-on exploration activities or (sometimes) lectures.  As the novice becomes an expert, the details of these individual episodes tend to fuzz together and a unified cognitive schema emerges.

Short-term Working Memory

As was mentioned in a previous answer, short-term memory can hold 5-9 discreet "chunks" of information.  To use programming terms, a chunk can either be a struct, where it represents actual data stored in working memory, or it can be a pointer to the location in long-term memory where a concept is stored.  This helps explain why experts can perform so much more quickly than novices, because their working memory can be much more efficiently utilized.

People rely on working memory to learn. As you learn, new information is incorporated into your existing mental model (this is known as constructivism).  This is an active process requiring the information to be reprocessed in working memory before it is stored into LTM.

Implications

The research above suggests that you need to take the system in pieces.  Learn what each piece does via a series of hands-on episodes, then move on to the next piece.  Then, come back and re-start this process.  As you do so, you will find yourself becoming more and more familiar with this complex system.


What qualitative studies are there into mindfulness? What qualitative studies, e.g. open ended interviews, are there into mindfulness therapy?

I've been skeptical about its use, wondered if it was kinda faddy. But it occurs to me that a lot of despair type emotions may have their root in being unable to relax and enjoy life. Surely meditation is linked with that?

Wikipedia often provides references to scientific studies and the Wikipedia article on Mindfulness is no exception.

The main section of the article has

  ...Studies have also shown that rumination and worry contribute to mental illnesses such as depression and anxiety,[13][14] and that mindfulness-based interventions are effective in the reduction of both rumination and worry.[13][15]

  Mindfulness practice is being employed in psychology to alleviate a variety of mental and physical conditions, such as bringing about reductions in depression symptoms,[16][17][18] reducing stress,[17][19][20] anxiety,[16][17][20] and in the treatment of drug addiction.[21][22][23] Recent studies demonstrate that mindfulness meditation significantly attenuates pain through multiple, unique mechanisms.[24] It has gained worldwide popularity as a distinctive method to handle emotions.

  Clinical studies have documented both physical and mental health benefits of mindfulness in different patient categories as well as in healthy adults and children.[3][25][26]

plus

  Research on the neural perspective of how mindfulness meditation works suggests that it exerts its effects in components of attention regulation, body awareness and emotional regulation.[34] When considering aspects such as sense of responsibility, authenticity, compassion, self-acceptance and character, studies have shown that mindfulness meditation contributes to a more coherent and healthy sense of self and identity.[35][36] Neuroimaging techniques suggest that mindfulness practices such as mindfulness meditation are associated with “changes in the anterior cingulate cortex, insula, temporo-parietal junction, fronto-limbic network and default mode network structures."[37][38] Further, mindfulness-induced emotional and behavioral changes have been found to be related to functional and structural changes in the brain.[38]

There is also a scientific research section

  Mindfulness has gained increasing empirical attention ever since 1970.[120][unreliable source?] According to a 2015 systematic review and meta-analysis of systematic reviews of RCTs, evidence supports the use of mindfulness programs to alleviate symptoms of a variety of mental and physical disorders.[25] Other reviews report similar findings.[19][22][33] Further, mindfulness meditation appears to bring about favorable structural changes in the brain,[32][37][121] and may also prevent or delay the onset of mild cognitive impairment and Alzheimer's disease.[122] Mindfulness proved to be effective also in enhancing people’s capacity to self-regulate.[123]

References

These are provided in the full article

This question is close to being put on hold or closed and to indicate why, it would produce a posting which is much longer than the standard laid out in the help center,

  if your question could be answered by an entire book, or has many valid answers, it's probably too broad for our format

plus, there are so many referenced studies and articles of scientific research connected to this (I counted 25 in total - 156 in the full article) that providing a full list of references here would take me an age to provide in full (with weblinks etc.) on this site.


What is the best way to structure an ethnographic study? I'm writing an ethnographic study for a human computer interaction module and I understand all the processes of conducting ethnography.

I am unsure of how to structure my study. Is it conventional to have it in an essay format, or are case studies preferred?

I have used ethnography for similar purposes several times. Structuring the interviews so that you are an apprentice and your subject plays the role of a master artisan works well.

The book, "Contextual Design" by Beyer and Holtzblatt provides several modeling techniques for expressing the information in some ways that add significantly to essay.

http://www.amazon.com/Contextual-Design-Customer-Centered-Technologies-ebook/dp/B003VM7GEC/ref=sr_1_1?ie=UTF8&qid=1382970418&sr=8-1&keywords=holtzblatt


Impact of pre-college schooling on IQ (WAIS)? Introduction

I'll give context for my question from personal experience, but then I'll generalize my question so that it's broadly useful.

When I was a child, my mother home schooled me. When I entered the 9th(?) grade, I dropped out. And for a few years prior to that, I cheated through most of my schoolwork. Someone suggested that even if I was cheating, I was still learning; this wasn't the case, because my cheating involved memorizing "A A B D B B A."

My understanding of the WAIS is that it merely serves as a way to approximate general intelligence, but it can't directly measure it (except perhaps working memory). And at least in cases like these, it won't work very well because it relies heavily on crystallized knowledge. When I took it, there were questions which I might have learned from school, but obviously I didn't have that experience; I believe this harmed my verbal IQ. You'll understand how verbal similarity and perhaps other sub scores could be likewise impacted. I also imagine that my math score suffered. My thinking is that there are numbers I would have been familiar with, thus reducing my response time. And I am more prone to error in my responses, due to lack of practice. I also would have had better schemes to quickly translate the data into an answer.

Total years of schooling the child missed
Age of child when those years are missed (college vs highschool)
Child's general intelligence (not as measured by the WAIS)

Questions:

How would increasing total years missed accumulatively affect IQ (e.g. 6 years = 9 points)? There's an article below about college increasing students' IQs, but what about K-12--would missing earlier years affect IQ more severely? And would missing school have more or less severe impact on IQ scoring among more intelligent children?

If the child (perhaps now an adult) studies, would the child's IQ increase relatively drastically? When I say relative, I mean relative to someone else who also studies and has the same real general intelligence, but did attend K-12. And to keep it simple, let's stick to math IQ score for this question.

Lastly, is there a better test for measuring such a person's intelligence?

I asked many questions, probably more than exists within current research. If you work in psychometrics or have approximately relevant knowledge, I'd be happy to hear your assumptions.

And if I need to reduce my questions, then consider the full-scale scores below. If those are the scores of someone who missed school as I described, then what score would you expect them to earn had they not missed school? ... And, is there a better test for them?

80
100
120

Related data:

Per the link below, adding a year of school increases IQ. Although not stated, they give the impression that this is referring to college.
 https://www.psychologytoday.com/us/blog/brainstorm/201806/how-much-does-education-really-boost-intelligence

Almost a week with no answer. I found an article covering part of the topic, though.

http://www.svt.ntnu.no/iso/torberg.falch/Articles/Article.pdf

THE EFFECT OF EDUCATION ON COGNITIVE ABILITY

TORBERG FALCH and SOFIA SANDGREN MASSIH

Economic Inquiry. Vol. 49, No. 3, July 2011, 838–856


Difference in MEG and EEG readings Reading the excellent clear answer from @RobinKramer to Are brain waves electromagnetic waves? I have become very interested in the mechanisms behind the measurement techniques using EEG and MEG.
From the answer, I understand that an EEG measures the action potentials within a neuron from one end to the other and a MEG measures the magnetic field generated by the action potentials. What I am wondering is; generally speaking, will the waveform outputs from each measuring device mirror each other in frequency and µV scales or are they different?

It seems I misunderstood how the outputs may be viewed from an MEG.
Magnetoencephalography (MEG) is a non-invasive test, which:

measures the magnetic fields generated by electric currents in the brain. The magnetic field measurements are in the range of femto-tesla to pico-tesla. MEG provides a very accurate resolution of the timing of neuronal activity (Singh, 2014).

A copyrighted image of an MEG recording can be viewed in Figure 3 of Singh (2014) and looks very different to a normal EEG with a typical montage, which can be viewed in Figure 1 within Louis, et al. (2016).
References
Louis, E. K. S., Frey, L. C., Britton, J. W., Hopp, J. L., Korb, P., Koubeissi, M. Z., ... & Pestana-Knight, E. M. (2016). The normal eeg. Electroencephalography (EEG): An Introductory Text and Atlas of Normal and Abnormal Findings in Adults, Children, and Infants [Internet]. https://www.ncbi.nlm.nih.gov/books/NBK390346/
Singh S. P. (2014). Magnetoencephalography: Basic principles. Annals of Indian Academy of Neurology, 17(Suppl 1), S107–S112. https://doi.org/10.4103/0972-2327.128676


Any studies on the link between popularity and happiness amongst school aged people? It is an interesting topic, at least to me, the psychology of people considered 'popular' at school and whether this perception of popularity is a coping mechanism for a deeper issue of self worth.

Could anyone link me any studies on this subject? If not, could you devolve any personal scientific opinion on the subject and any studies that may help in my further study of perceived social popularity.

I am not very familiar with the field, but a quick Google search brought up this paper ("The Happiness Paradox: Your Friends are Happier Than You" from Bollen, Goncalves, Leemput, and Ruan) which had some interesting results and conclusions. This paper considers a happiness paradox within the concept of friendships, and a friendship paradox within the concept of happiness. It also includes correlation coefficients between happiness and popularity, which may address your question. I'll note that the sample of this study isn't exactly what you are looking for: it is done via Twitter data (and, as noted in the supplementary materials of the paper, the sample only includes users with greater than 15 friends).

Results seem to show that there is a mild correlation for "happy people", but there is not much of a correlation for "unhappy people" (very slight, though statistically significant, negative correlation). For more details, I encourage you to read the article (which includes some nice graphics depicting their theories and the distributions of outcomes).

Perhaps a start in the right direction?


How to generate ipsative scores from a test with normative Likert-type items? Some constructs in psychology are sometimes conceptualised ipsatively. I.e., where the sum of the scales adds up to a constant (e.g., personal values; coping styles). The aim of such measures is often to show the relative position on such scales. In some cases, such scales are created by their response format (e.g., participants respond to questions that require some form of rank ordering of constructs). However, it is also possible to score tests with normative items (e.g., 20 items each on 1 to 5 scale, measuring 4 constructs) in an ipsative way.

However, I recently ran into confusion about exactly how such ipsatised scores should be computed. I can think of a few different ways (e.g., subtracting the mean across all items from each item; dividing scale scores by sum of scale scores; saving residuals where scale is predicted by total score, etc.). I imagine many of these approaches yield similar variables. However, if you need to write a paper using ipsatised scores, you need to justify your particular approach.

Is there a standard way of performing ipsatisation on scales made up of normative likert-type items?

Baron (1996) writes:

  Scores on a multi-scale measure are ipsative when raw scale scores sum to a constant for any individual.
  An ipsative score can be thought of as the normative equivalent controlled for overall total score across scales.

Meade (2004) describes perhaps the most common form of ipsatisation based on normative scores as "deviational ipsative" (Radcliffe, 1963):

  normative data (e.g., Likert scales) can be made to be ipsative by simply subtracting the grand mean of each individual’s scale scores (averaged across all scales) from each of his or her individual scale scores (i.e., ipsatized data, Cattell, 1944; additive ipsative data (AID), Chan & Bentler, 1993);

But it seems that there are range of other ways to create ipsative scores (i.e., that satisfy the formal requirement).

The above substraction method can also involve dividing by the within-person population standard deviation.
Save the residuals of a regression model predicting each scale from the mean of all scales

I ran quick comparison on some personality data and it seemed like the residual regression and the deviation approach achieved very similar results (see R code at the bottom of post. Thus, it makes sense that the simpler to calculate deviation approach is often applied.

References

Radcliffe, J. A. (1963). Some properties of ipsative score matrices and their relevance for some current interest tests. Australian Journal of Psychology, 15(1), 1-11.
Meade, A.W. (2004). Psychometric problems and issues involved with creating and using ipsative measures for selection. Journal of Occupational and Organizational Psychology (2004), 77, 531–552.
Baron, H. (1996). Strengths and limitations of ipsative measurement. Journal of Occupational and Organizational Psychology, 69(1), 49-56.

R code

> # load some personality data
> library(psych)
> data(bfi)
> scales <- c("a1", "a2", "a3")
> names(bfi) <- tolower(names(bfi))
> bfi <- bfi[,scales]
> bfi <- na.omit(bfi)
> head(bfi)
      a1 a2 a3
61617  2  4  3
61618  2  4  5
61620  5  4  5
61621  4  4  6
61622  2  3  3
61623  6  6  5
> # calculate overall mean
> bfi$omean <- apply(bfi[,scales], 1, mean)
> # calculate ipsative scores based regression residuals
> bfi$res_a1 <- resid(lm(a1 ~ omean, bfi))
> bfi$res_a2 <- resid(lm(a2 ~ omean, bfi))
> bfi$res_a3 <- resid(lm(a3 ~ omean,bfi))
> # calculate devaiation ipsative scores
> bfi$dev_a1 <- bfi$a1 - bfi$omean
> bfi$dev_a2 <- bfi$a2 - bfi$omean
> bfi$dev_a3 <- bfi$a3 - bfi$omean
> # check that both satisfy ipsatisation requirement
> all(round(apply(bfi[,paste0("res_", scales)], 1, sum), 6) == 0)
[1] TRUE
> all(round(apply(bfi[,paste0("dev_", scales)], 1, sum), 6) == 0)
[1] TRUE
> # Examine similarities between approaches (see diagonal)
> round(cor(bfi[paste0("res_", scales)], bfi[paste0("dev_", scales)]), 3)
       dev_a1 dev_a2 dev_a3
res_a1  0.981 -0.729 -0.711
res_a2 -0.716  0.999  0.065
res_a3 -0.718  0.067  0.971


What is the difference between a schema and a heuristic? I am trying to understand the basic differences, in layman's terms, between a schema and a heuristic

A heuristic consists of preferences that help you decide in a situation where you do not have enough information or do not care enough to make an informed decision. For example, when you want to buy yoghurt, but are no nutritionist, you might decide on which yoghurt you buy by the familiarity of the brand name (you prefer the familiar, this is called the familiarity heuristic) and other aspects that have nothing to do with the yoghurt itself.

A schema is a workflow or storyboard that tells you what to do in a recurring situation. For example, when you go shopping you might follow an internal script to make shopping more efficient: you pick the same products in the same sequence every time. You know in advance what you will buy, there are no decisions involved, in fact you ignore all alternative products. A schema allows you to navigate familiar, recurrent and similar situations by following the same sequence of actions.


What is the function of the connection between the two halves of the thalamus? What kind of direct exchange do we have between the two halves of the thalamus, whether going through the thalamic adhesion or not? Do we know what parts of left and right thalamus are connected and what kind of information they exchange?

Short answer
The function of the thalamic adhesion in humans is unknown.

Background
The two halves of the thalamus are separated by the third ventricle. In about 80% of people, the thalami are connected via the thalamic adhesion (massa intermedia, Fig. 1), which mainly contains cell bodies, but also commissural fiber systems that connect some thalamic nuclei (Satheesha & Soumya, 2010; Sen et al., 2005). Because the structure is absent in about 20% of the people, it is not a critical structure. The significance and consequences of its presence or absence is not known in humans (Sen et al., 2005).

It is known that there are sex-differences between the presence of the structure. It is present in 78% of females and 68% males (Allen & Gorski, 1991) and it is about 50% bigger in females, when present. In schizophrenics, female patients were shown to have a significantly higher incidence of absent massa intermedia (33%) than their healthy controls (14%), whereas male patients showed no such difference (Nopoulus et al., 2001).

In rhesus monkeys, ablation of the structure has been shown to lead to ipsilateral motor deficits (Lumley, 1972), but that has likely no relation to the commmissural tracts in question.

Fig. 1. Dissection showing the massa Intermedia connecting the two thalami through the third ventricle. source: Wikipedia

References
- Allen & Gorski, J Comp Neurol (1991); 312(1):97-104
- Lumley, Brain (1972); 95(2): 347-56
- Nopoulus et al., Schizophr Res (2001); 48(2-3): 177-85
- Satheesha & Soumya, Int J Anatomic Var (2010); 3: 174–5
- Sen et al., Neuroanatomy (2005); eISSN 1303-1775 • pISSN 1303-1783


Are there studies on international differences on sexualization? With sexualization, I mean the reaction that one has when seeing the desired sexual object. I guess that in some countries, their cultures may have softer reactions, while in others, a stronger reaction could even imply rape.

Anthropologists have shown that all cultures have the same "amount" and "intensity" of modesty, shame and sexual excitability. What differs are clothing and behavioral habits, and therefore what is considered modest, what causes shame, and what causes sexual arousal.

The most extensive meta-analytic study on this topic is Hans-Peter Duerr's five volume Der Mythos vom Zivilisationsprozeß [The Myth of the Civilizing Process] (1988-2002), in which he collects and interprets ethnological, archaelogical and sociological research from all cultures and times regarding nudity and shame, intimity, obscenity and violence, eroticism, and defecation, in a reply to Norbert Elias' famous The Civilizing Process (1939).

You can think of the variation in modesty and sexualization over cultures as a border of the public display of the body that can be moved along a continuum from the eyes (burqa)

via the extremities (Victorians had to cover their legs)

more and more towards the center of the body (swimsuit)

narrowing down to the secondary sex characteristics (bikini)

the genitals (penis sheath or female modesty girdle [pictured below])

and finally the male glans (kynodesme) and the inside of the female labia

That peoples that live totally nude are not without shame and modesty can be seen from their social rules and the reactions to their transgression that Duerr reports. A telling example is how the girls of one naked tribe are not allowed to sit with their legs spread (so the insides of the labia don't become visible to the men), how the men attempt to catch a glimpse while the girls and women go about their day and react with excitement when they manage to see something forbidden, and how girls are being ridiculed if this happens. This is much the same as how we act with short skirts, the blowing wind and candid street photography.

Duerr lists page after page after page of research showing examples similar to this and to the one you gave in your comment (desexualized breasts). Unfortunately I don't know of a good English language overview so I can only recommend that you follow Nick's links and research tipps, if you want to get more deeply into this hotly debated area.


According to Yalom, what mental disorders are caused by inefficient anxiety coping strategies? Irwin D. Yalom is a famous existential psychotherapist who's sporting his own theory about human psychology. Based on psychdynamics, he's stating that questions and thoughts pertaining to death, freedom, meaninglessness, and existential isolation lead to anxiety. Further, when it comes to psychopathology, he states (page 110 of his book Existential psychotherapy) that his theory

  as do most paradigms of psychopathology, on the assumption that
  psychopathology is a graceless, inefficient mode of coping with
  anxiety.

Now, I'm trying to figure out whether he views all kind of psychopathology this way, and indeed what he thinks counts as psychopathology in the first place. I recon he's not talking about things like for example autism or psychopathy (even though I haven't found any passages where he explicitly excludes these), but what about diagnoses such as schizophrenia?

For Yalom, where does one draw the line between mental illness caused by inefficient coping strategies for anxiety, and brain disorders that simply are due to other reasons?

The scope of Yalom's mainstream branch is pretty much the same as that of existential psychotherapy, and psychodynamic therapy in general.  According to Yalom (p. 9-10):

  The dynamic existential approach retains the basic dynamic structure
  outlined by Freud, but radically alters the content.  The old formula
  of DRIVE -> ANXIETY -> DEFENSE MECHANISM is replaced by AWARENESS OF
  ULTIMATE CONCERN -> ANXIETY -> DEFENSE MECHANISM. Both formulas assume
  that anxiety is the fuel of psychopathology;

Psychoanalysis is focused on psychological symptoms, such as neurosis:

  There are many different neuroses: obsessive–compulsive disorder,
  obsessive–compulsive personality disorder, impulse control disorder,
  anxiety disorder, hysteria, and a great variety of phobias. ...
  anxiety, sadness or depression, anger, irritability, mental confusion,
  low sense of self-worth, etc., behavioral symptoms such as phobic
  avoidance, vigilance, impulsive and compulsive acts, lethargy, etc.,
  cognitive problems such as unpleasant or disturbing thoughts,
  repetition of thoughts and obsession, habitual fantasizing, negativity
  and cynicism, etc. Interpersonally, neurosis involves dependency,
  aggressiveness, perfectionism, schizoid isolation, socio-culturally
  inappropriate behaviors, etc.

and psychosis, but exclusive of known biological causes:

  Medical and biological laboratory tests should exclude central nervous
  system diseases and injuries, diseases and injuries of other organs,
  psychoactive substances, toxins, and prescribed medications as causes
  of symptoms of psychosis before any psychiatric illness can be
  diagnosed.

As per Yalom (p. 12):

  *In this discussion, as elsewhere in this text, I refer to
  psychologically based disturbance, not to the major psychoses with a
  fundamental biochemical origin.

This is similar in scope to all forms of psychotherapy, except that where the underlying cause is not known to be physiological or medical in nature, it is assumed to be subconscious (rather than say, behavioural, cognitive, or functional).  For psychodynamics:

  Psychodynamic therapies depend upon a theory of inner conflict,
  wherein repressed behaviours and emotions surface into the patient’s
  consciousness; generally, one's conflict is subconscious.

and specifically, for existential psychotherapy (in Yalom's words p. 8):

  ... a conflict that flows from the individual's confrontation with the
  givens of existence.

This also means that the scope of therapy may change over time, as knowledge is gained regarding the root causes of mental disorders.

Pretty much all other mental disorders are fair game, including mood disorders such as anxiety, personality disorders such as psychopathy (ASPD), and thought disorders such as schizophrenia.  For example, in chapter 4 (p. 147) of his book - under the "Death" concern - Yalom discusses schizophrenia patients who:

  clings to his or her denial of death with a fierce desperation

Note: In cases where some biological factor is assumed, it is common practice to treat disorders with both medication and psychotherapy, as the overall efficacy is improved.  In such cases, psychotherapy focuses on the psychological components of the disorder.  Even in cases where the role of psychology may seem secondary, such as dementia, learning disability, and autism, psychotherapy may be used to augment treatment.  However, psychodynamic therapy is not popular for such disorders, because of the reliance on talk-therapy, that is highly constrained in these cases, so they are unlikely to be discussed much in existential therapy circles.


What does it mean for there to be more variance within groups than between groups in IQ? I was watching a short YouTube video that comments on the validity of IQ. That video contains the following claim (verbatim):

  "You know nothing about a person's intelligence on the basis of his or her skin color. That is just a fact. There is much more variance among individuals in any racial group than there is between groups..."

This was shortly after he stated that there are real differences in the average IQ of different races.

I find the bold statement confusing and am not certain how to interpret it. I understand what variance means when discussing a single probability distribution however, my learning never extended to variance between distributions. Could someone please explain how this is done and more importantly, why this measure justifies the first (non-bold) statement?

In the video he is discussing some work of Charles Murray (not sure how familiar you are with it). In any case, the main point of your confusion comes from the difference between presence and size. Dr. Harris admits that there are differential IQ values between the races: there is (presence) a difference. The immediate follow up, though, is that the size of that difference pales in comparison to the variability with the group, indicating that no practical conclusions can be made.

For a silly example (and not leave any Earth groups out), consider Martians and Plutons (poor Pluto...): Martians may have a slightly higher IQ than Plutons, but the variability within each group is much higher than the between group difference. Dr. Harris' whole point is that, upon meeting a random Pluton and a random Martian, you practically have no idea which of them will be smarter, even though we know that Martians tend to be smarter. A pretty picture illustrates the two groups below.

I hope this helps! Take home message from the video is that even though there are small differences between races in terms of IQ, they should not play a role in someone's judgement of another person due to the immensely higher variability of IQ within any given race (there are some super smart Plutons and some super dumb Plutons, just like there are some super smart Martians and some super dumb Martians: you won't know which you are speaking to until you actually talk to them).

Graph coded in R:

boxplot(cbind(Plutons = rnorm(1000, mean=100, sd=15), Martians = rnorm(1000, mean=102, sd=15)))


In which way does what you do right after class affect knowledge retention? For example going for a walk in the woods right after the class sounds like a much better idea than to binge watch 5 Rick & Morty episodes... but why?

In which way do your right-after-class activities affect your brain's ability to retain what you've just learned?

The reason you instinctively feel that a walk in the woods is better than TV may be partially related to the schemas you've developed around both activities. You get the feeling that talking a walk is a more "intellectual" activity than TV because that's you expectation based on what you've heard, and your experiences of TV being a lazy activity for pleasure, not because TV inherently "rots your brain".

That said, the other half of things is probably the answer you're looking for. Right after class, your memories of the lecture are still malleable and not yet incorporated into long-term memory. The Wikipedia article on this is a good place to start:

https://en.wikipedia.org/wiki/Memory_consolidation


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

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

Short answer
The open palms are usually seen as a gesture of openness.

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

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

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

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


Anti-psychotic medication withdrawal-induced psychosis Can psychosis result from anti-psychotic medication withdrawal for a non-psychotic patient? That is, a patient that takes anti-psychotic medication for off label reasons, such as treatment-resistant depression, or insomnia.

It depends on what you mean by psychosis.

Anti-psychotic medications effectively reduce the positive symptoms of schizophrenia (hallucinations, paranoia) at the expense of worsening the negative symptoms (rigidity, bradykinesia, cognitive slowing). Long-term use of antipsychotics, especially the older ones, can induce a Parkinson's-like syndrome.

These effects are not withdrawal so much as side effect of the medication.

Second generation antipsychotics are used as mood stabilizers in bipolar II and major depression. Post-marketing surveys of aripiperazole and the like have not bred rebound psychosis.

Use of dopamine agonists is associated with psychosis.


Does a split brain affect the inner voice? In the Nature link provided, split brain reportedly alters the processing of sensory input (e.g., an aberrant performance on monocular visual tasks under laboratory conditions), and impairs motor output execution (e.g., impaired ability to make goal-directed movements).
Now my question is whether a split brain (corpus callosotomy) affects the ability to have an internal monologue in any way?
I'm curious of that because I heard about "Bicameral mind" theory (although I didn't read the book) and that on of the reasons of "bicameralism" was weak connection between hemispheres. I couldn't find anything about formation of inner voice and decided to ask.
Source
- Nature News, 2012

Short answer: Probably not.
Let's first keep in mind that very few split-brain patients have ever been studied.  Add to this that inner speech is not a well studied area in general.  As the resulting Venn diagram suggests, there is next to nothing known about inner speech in split-brain patients.
Second, remember that one of the key reasons why inner speech is problematic to investigate is because up until recently, our main data source has been self-reports, considered notoriously unreliable as a methodology.  This is especially exacerbated in patients with awareness deficiencies such as split-brain.
Having said that...
Split-brain patients in general report no significant post-operative changes in their cognitive function, sense of self, or conscious experience.  Internal monologue remains intact, and appears to function as normal.  However testing under lab conditions demonstrates that subjects do in fact experience significant changes in awareness - effectively neglecting half of their perceptual experience.
If self-reports of awareness are so significantly inaccurate, then what are we to make of split-brain patients' self-evaluation of conscious experience and other cognitive functions?  The truth is, we just don't know.
Relatively recently, new techniques for studying inner speech have been developed, such as fMRI imaging of subjects instructed to or prevented from engaging in self-reflection and internal monologue.  Such studies suggest that inner speech is primarily localized to Broca's area (LIFG, on the left side of the brain), just as is outer speech (McGuire, 1996; Morin & Hamper, 2012; Wikipedia).  These findings are consistent with other evidence that inner speech is a form of silent (simulated) outer speech, and thus uses the same physical mechanism.
In the split-brain paradigm experiments, subjects are able to articulate stimuli presented to their right field of view (left hemisphere, where Broca's area is), but unable to do so for stimuli presented to their left side (right hemisphere, where language is lacking).  To communicate with the right hemisphere, researchers have subjects use their left hand to gesture responses in some way.
These experiments were instrumental in localizing language function in the brain, and they demonstrated that language capabilities are largely lateralized in the left hemisphere.  However, the right hemisphere has sufficient language understanding capabilities to gesture meaningful responses without the left hemisphere's awareness.
So although it's tempting to suggest that inner speech, localized in Broca's area on the left side of the brain, should be unaffected by corpus callosotomy, as reported by split-brain patients, the language capabilities of the right hemisphere leave open the possibility that a separate experience may exist there, potentially implying some reduction in function of (outer and inner) speech in the left side.
And indeed, while language function is highly lateralized in 90% of right-handed people, function is more evenly distributed amongst the hemispheres in other cases.  By some stroke of luck, this was the case in a particularly interesting split-brain patient by the name of Paul S.
Remarkably, in the experiments conducted with Paul, he was able to use his left hand to spell out single word answers using Scrabble pieces to express what his right hemisphere was thinking (LeDoux et al, 1977).  As with other split-brain subjects, his right hemisphere had a quite different experience from his left, but unlike other patients, Paul was able to demonstrate a slightly different personality residing in his right brain, with different opinions, preferences, and decisions.
Could this mean that Paul S. had a second, independent internal monologue in his right hemisphere that the left hemisphere was unaware of?  The dual-consciousness interpretation of this case study has been the subject of much debate, but most scholars suspect that this is unlikely: Language function is simply too rudimentary in the right hemisphere, even in this remarkable case, to plausibly support this hypothesis.


Is there an audio equivalent of eidetic memory? In this YouTube video by The Blaze it is claimed that Ted Cruz has "audiographic" memory. He does seem to have quite a good memory based on videos I've seen of him, but I'm not sure if Glenn Beck is exaggerating and I can't find the Wall Street Journal article he's referring to.

I know about eidetic memory (photographic memory):

  ... is an ability to vividly recall images from memory after only a
  few instances of exposure, with high precision for a brief time after
  exposure, without using a mnemonic device.

Is there something similar for audio exposures and recall? Audiographic memory does not seem an academic term. Is this phenomenon discussed in academia?

I have been doing some research and this is what I found so far.

First, the memory of sounds is called echoic memory (Alley Dog; Echoic Memory Definition) and is a form of sensory memory. This means that by nature, it is short-term.

However, I found an interesting wikipedia article, followed the source, and found that, in fact, it appears that eidetic memory also includes remembering sounds! (Taylor;  Encyclopedia of Human Memory; Superior Autobiographical Memory; p.1099).
So it could be that there isn't a term for it because it is included in this.

When it comes to 'audiographic memory', a thorough search leads me to thinking that indeed, it's not an academic term and is not researched or discussed as such. The only things I can find that use that word are of questionable validity (ex: Bates, Unconscious Processes, 2009).

For some reason, the video link does not work for me, but I hope that this information makes things clearer for you!

Other sources:
-Wikipedia Page; Echoic Memory
-Wikipedia Page; Eidetic Memory


relation of substantive/verb to declarative/procedural memory Is there a relation between "declarative vs. procedural memory" and "substantive vs. verb"?
For example, are substantives (as a kind of information entities) stored in the declarative memory whereas verbs define capabilities/behavior and hence stored in the procedural memory?

Example:

Tree: a substantive, can directly be stored in declarative memory

to climb: a verb, defines a capability/behavior and can be stored in the procedural memory

While it's true that universal nouns will link mostly to other universal nouns (a tree is a plant), and universal verbs will link mostly to other universal verbs (to climb is to move), it is not necessary that they be in separate memory areas from each other; or even that they be separate from event memory (one cat did climb one tree).  The most efficient memory scheme would minimize the length of all links.  One way would be to store all new memories in a fairly linear structure, and then use an off-line process (sleep) to spread them around to minimize total link lengths {or to optimize lengths around importance of fast access}.


Can non-verbal communication in interpersonal relationships be taught rather than acquired? In my experience people living together in difficult circumstances (e.g. close friends, family members) often learn to relate to each other's non-verbal cues.

For instance; A spouse may go shopping with a list in hand prepared by his partner, and return with a few items not mentioned on the list - only to have his partner indicate one or more items were missed by oversight. Similarly people sharing a room in a hostel may merely by a glance communicate an unspoken understanding of intent & action.

Understandably such incidents probably do not occur with high frequency. They are, however, not totally rare either. This brings me to my question:

Can such non-verbal communication be taught rather than acquired?

Can non-verbal communication in interpersonal relationships be taught rather than acquired? In many ways this question answers itself. As an acquired skill is one that is learnt, and by definition, anything that can be learnt can be taught.

As with many skills, non-verbal communication begins in childhood.

  It is concluded that style of expression and skill in communication
  are influenced by the emotional expressiveness of the family
  environment.

Family socialization of emotional expression and nonverbal communication styles and skills.
Halberstadt, Amy G.
Journal of Personality and Social Psychology, Vol 51(4), Oct 1986, 827-836

Unlike, many, subconscious difficulties of the mind, learning to read body language can be practiced and improved. A simple google search reveals some of the books and online resources to teach people to improve these skills.

This article discusses the formal study of  improving the  non-verbal communication skills to children with deficiencies in this area.

Teaching Approach for Developing Nonverbal Communication Skills in Students with Social Perception Deficits
Part I. The Basic Approach and Body Language Clues
Esther H. Minskoff, PhD


The effects of bilingualism on colour perception Peltola et al. (2012) showed that there are two types of bilinguals.

Balanced bilinguals mix their two languages and are effected by linguistic categories from both.
Dominant bilinguals seem to switch on the categories of the language they are using, and suppress the categories of the language not in use.

The task Peltola et al. (2012) studied was phoneme categories. The boundaries between vowels are arbitrary and set by the language of the user. The researchers focused on two sounds that are categorised as different vowels in Finnish, but are the same vowel in Swedish. When dominant bilingual participants were briefed about the study in Finnish, they distinguished the sounds quickly. When the same participants were briefed about the same experiment a week later in Swedish, their ability to distinguish the sounds slowed significantly. The balanced bilinguals were equally slow under both briefings.

A similar arbitrary language-dependent categorization exists in colour perception (Regier & Kay, 2009). In fact, the effect of this arbitrary categorization is even lateralized: the Whorf hypothesis is supported in the right visual field but not the left (Gilbert et al., 2006)! So the basics of linguistic relativity seem to be cross-modal.

Do dominant bilinguals switch linguistic categories on and off in the visual domain? Is the result of Peltola et al. (2012) cross-modal?

This paper was written in 2010:

Perceptual shift in bilingualism: brain potentials reveal plasticity in pre-attentive colour perception.

  In this paper, we test whether in Greek speakers exposure to a new
  cultural environment (UK) with contrasting colour terminology from
  their native language affects early perceptual processing as indexed
  by an electrophysiological correlate of visual detection of colour
  luminance. We also report semantic mapping of native colour terms and
  colour similarity judgements. Results reveal convergence of linguistic
  descriptions, cognitive processing, and early perception of colour in
  bilinguals.

There are some important (but speculative) considerations here, in my opinion:

1) Aspects of color are defined culturally.  Each culture arbitrarily places borders to divide the regions of a continuous spectrum and we pass these divisions on to our children.

2) Different cultures may have non-overlapping hues distributed across a coarse division.  For instance, if we took the coarse color "green" and divided it up into 15 shades so that my greens are 3, 8, and 12 and my foreign friend's is 8, 10, and 15 are hues that we each strongly associate with green (because they're typical in our culture).  However, my 3 is too close to yellow for my foreign friend and his 15 is too close to blue for me (and I want to call it "aqua").

3) There's also the difficult that the colors we experience in the world aren't pure colors on a ROYGBIV spectrum.  An apparently uniform garment can often be small-grain ensembles of many different colored threads.


Do transgender people typically get tested for intersex conditions? I tried searching on my own but can’t even come up with proper search terms.

Prior to medical transition, do people undergo testing for conditions like Congenital Adrenal Hyperplasia or XXY? Although in some cases it’s visually clear that somebody is intersex, in others such as XXY, the person can be unaware their entire life unless they are specifically tested.

undergo testing for conditions like Congenital Adrenal Hyperplasia or XXY?

No.

Chromosomal screening is not routinely done according to the recently released Australian guidelines.
The issue is whether there is a relationship between transgenderism and intersex conditions and no there is not. If a condition is not higher than the usual population, then there is no evidence to screen and perform investigations that are unlikely to produce any useful outcomes. Transgenderism seems to be an independent phenomenon and does not seem to have a relationship with intersex conditions according to current research.

  Chromosomal analyses are rarely abnormal in TGD individuals and should only be performed if there is clinical suspicion (eg, Klinefelter syndrome). Genital examination is not routinely required.

References:

Cheung, A. S., Wynne, K., Erasmus, J., Murray, S., & Zajac, J. D. (2019). Position statement on the hormonal management of adult transgender and gender diverse individuals. The Medical Journal of Australia, 211(3), 127–133.