Does breastfeeding lead to increased intelligence?

Kramer et al 2008 is an excellent study of this question because it utilizes intervention, thus lending strength to the claim of causation, concluding that IQ was "significantly higher in the experimental group for both reading and writing".

But is it the milk itself?  Some argue that it's also the skin-to-skin contact, and the mother-child bonding. Academic success has been shown to be strongly correlated with emotional intelligence (e.g., Parker et al, 2004 found $r=.33$ between GPA and EI in a large sample of high school students) and some Attachment Theory proponents claim closer parental relationships lead to stronger emotional intelligence.  However, some studies demonstrate that only adults happiness is positively effected by percieved parental attachment, not emotional intelligence (e.g., Sillick & Schutte, 2006) and that emotional intelligence is correlated with a dismissive attachment style (Kafetsios, 2004).

The Arch Gen Psych article comments on potential mechanisms:

  Even though the treatment difference appears causal, it remains unclear whether the observed cognitive benefits of breastfeeding are due to some constituent of breast milk or are related to the physical and social interactions inherent in breastfeeding. Concentrations of essential long-chain polyunsaturated fatty acids are higher in human milk than in infant formula. Randomized trials of supplementation of infant formula with long-chain polyunsaturated fatty acids, however, have yielded inconsistent results in both term [21] and preterm [22] infants. Another potentially important component of breast milk that could be responsible for the observed cognitive differences is insulinlike growth factor I, which is contained in higher concentration in breast milk than in formula [23] and has been shown to be absorbed intact across the newborn infant's gastrointestinal tract.[24]

  On the other hand, studies showing long-term epigenetic behavioral
  effects of licking and grooming by mother rats of their pups [25] suggest
  that the physical and/or emotional act of breastfeeding might also
  lead to permanent physiologic changes that accelerate neurocognitive
  development. Finally, it is possible that the increased frequency and
  duration of maternal-infant contact implicit in breastfeeding vs
  bottle-feeding could increase verbal interaction between mother and
  infant, which might also have a stimulatory effect on cognitive
  development.

  [21] Simmer  K. Longchain polyunsaturated fatty acid supplementation
  in infants born at term [update of: Cochrane Database Syst Rev.
  2000;(2):CD000376]. Cochrane Database Syst Rev 2001; (4) CD000376

  [22] Simmer  K, Patole  S. Longchain polyunsaturated fatty acid
  supplementation in preterm infants [update of: Cochrane Database Syst
  Rev. 2000;(2):CD000375]. Cochrane Database Syst Rev 2004; (1)
  CD000375.

  [23] Nagashima  K, Itoh  K, Kuroume  T. Levels of insulin-like growth
  factor I in full- and preterm human milk in comparison to levels in
  cow's milk and in milk formulas. Biol Neonate 1990;58 (6) 343- 346

  [24] Philipps  AF, Rao  R, Anderson  GG, McCracken  DM, Lake  M,
  Koldovsky  O. Fate of insulin-like growth factors I and II
  administered orogastrically to suckling rats. Pediatr Res 1995;37 (5)
  586- 592

  [25] Weaver  IC, Cervoni  N, Champagnhttp://ojs.lib.swin.edu.au/index.php/ejap/article/viewFile/71/100..e  FA, D'Alessio  AC, Sharma  S,
  Seckl  JR, Dymov  S, Szyf  M, Meaney  MJ. Epigenetic programming by
  maternal behavior. Nat Neurosci 2004;7 (8) 847- 854

References

Kafetsios, K. (2004). Attachment and emotional intelligence abilities across the life course. Personality and Individual Differences, 37, 129-145.
Kramer, M.S., Aboud, F., Mironova, E., Vanilovich, I., Platt, R.W., Matush, L., Igumnov, S., Fombonne, E., Bogdanovich, N., Ducruet, T. & others (2008). Breastfeeding and child cognitive development: new evidence from a large randomized trial. Archives of General Psychiatry, 65, 578.
Parker, J.D.A., Creque, R.E., Barnhart, D.L., Harris, J.I., Majeski, S.A., Wood, L.M., Bond, B.J. & Hogan, M.J. (2004). Academic achievement in high school: does emotional intelligence matter?. Personality and Individual Differences, 37, 1321-1330. PDF
Sillick, T.J. & Schutte, N.S. (2006). Emotional intelligence and self-esteem mediate between perceived early parental love and adult happiness. E-Journal of Applied Psychology, 2. PDF


First of all, it is important to note that the current version (5th Edition) of the DSM — Diagnostic and Statistical Manual of Mental Disorders, published by the American Psychological Association (APA, 2013) — does not recognise homosexual obsessive-compulsive disorder (HOCD) as a mental health condition (Smith, 2021).

Homosexual obsessive-compulsive disorder (HOCD) is a type of sexual orientation-obsessive-compulsive disorder (SO-OCD). A person with SO-OCD may have fears and anxieties relating to their sexual orientation.
[...]
A person with HOCD may have anxiety about experiencing same-sex attraction, even if they do not experience this.
Because HOCD is a type of SO-OCD, some people may use the term to refer to situations wherein people who are not heterosexual experience fears about their sexual orientation.

Reading this article will explain in more detail what HOCD is reportedly all about.
Can sexual orientation change due to HOCD?
The overarching point to put across regarding any sexual orientation is that nothing and nobody can make you homosexual, bisexual or heterosexual. There have been groups of therapists who tout that they can convert homosexuals into heterosexuals through conversion therapy, but:

conversion therapy in relation to gender identity and sexual orientation (including asexuality) is unethical, potentially harmful and is not supported by evidence (BACP, 2017).

For research on this, among many others there is:

Drescher, J., Schwartz, A., Casoy, F., McIntosh, C. A., Hurley, B., Ashley, K., ... & Tompkins, D. A. (2016). The growing regulation of conversion therapy. Journal of Medical Regulation, 102(2), 7-12. https://doi.org/10.30770/2572-1852-102.2.7

Assessments of the peer-reviewed literature from multiple professional organizations, including the American Psychiatric Association, the American Psychological Association, and the American Academy of Child and Adolescent Psychiatrists, have found no evidence that conversion therapy treatments result in changes in sexual orientation.

Haldeman, D. C. (1994). The practice and ethics of sexual orientation conversion therapy. Journal of Consulting and Clinical Psychology, 62(2), 221–227. https://doi.org/10.1037/0022-006X.62.2.221

The literature in psychotherapeutic and religious conversion therapies is reviewed, showing no evidence indicating that such treatments are effective in their intended purpose

Adelson, S. L., & of Child, T. A. A. (2012). Practice parameter on gay, lesbian, or bisexual sexual orientation, gender nonconformity, and gender discordance in children and adolescents. Journal of the American academy of child & adolescent psychiatry, 51(9), 957-974. https://doi.org/10.1016/j.jaac.2012.07.004

Principle 6
Clinicians should be aware that there is no evidence that sexual orientation can be altered through therapy, and that attempts to do so may be harmful.

This led to the Coalition Against Conversion Therapy (CACT), a coalition of leading psychological, psychotherapeutic, and counselling organisations committed to ending conversion therapy, who prepared a Memorandum of Understanding (MoU) on Conversion Therapy in the UK (UKCP, 2017), and signed by many UK professional governing bodies, including (see the corresponding links) the National Counselling Society (NCS), British Association for Counselling and Psychotherapy (BACP), National Health Service (NHS), The British Psychological Society (BPS), and the Royal College of General Practitioners (RCGP).
References
APA. (2013). Diagnostic and statistical manual of mental disorders (DSM-5®). American Psychiatric Pub. https://www.psychiatry.org/psychiatrists/practice/dsm
BACP. (2017). Memorandum of understanding on conversion therapy in the UK https://www.bacp.co.uk/events-and-resources/ethics-and-standards/mou/
Smith, A. (2021). What is homosexual obsessive-compulsive disorder (HOCD)? Medical News Today https://www.medicalnewstoday.com/articles/hocd
UKCP (2017) Conversion Therapy https://www.psychotherapy.org.uk/policy-and-research/public-policy/conversion-therapy/


What are some known roles or correlations of glucocorticoid receptor function to behaviour?

First off, the question is superbly broad and it would have faced closure if it would be asked at the time of this writing. Nonetheless, given the high number of upvotes I think it deserves an answer. Note that my answer is just a small bunch of behaviors associated with the NR3C1 gene, as based on a cursory Google Scholar search, using the terms 'NR3C1 + behavior'.

NR3C1 gene polymorphisms have been associated with alcohol and drug abuse (Zen et al, 2010), aggression (Li et al., 2017) and suicide (Park et al., 2016)
NR3C1 hypermethylation has been associated with being bullied or lacking friends (Efstathopoulos et al., 2018 and with PTSD (Vukojevic et al., 2016)
Cry acoustics in infants is associated with methylation pre-term (Sheinkopf et al., 2016)

References
- Efstathopoulos et al., Translat Psychiatry (2018); 8(121)
- Sheinkopf et al., Front Behav Neurosci (2016)
- Li et al., Genet Test Mol Biomarkers (2017); 21(8): 497-505
- Park et al., Behav Brain Functions (2016); 12:22
- Vukojevic et al., J Neurosci (2014); 34(31): 10274-84
- Zhen et al., Prev Sci (2016)


Is religiousness a genetically heritable feature?

Monozygotic twin studies are the general course of action for this kind of question. Genetic and environmental influences on multiple dimensions of religiosity: a twin study concludes there is a genetic component.

A complete approach for these kind of studies is to take twins that have been separated to different households from birth and compare them to twins in the same household. I'm not sure what this particularly study does (haven't read it) but its a typical approach in behavioral biology.

A summary of the above article, also references a book where they compared monozygotic twins to dizygotic twins.

The difference between monozygotic and dizygotic twins is that monozygotic twins share almost a complete set of genetics (mutations happen) while dizygotic twins share the same amount as a normal set of siblings.  The idea being that if monozygotic twins share traits at a higher statistical rate than dizygotic twins, that there is a genetic component to that trait.  This, of course, does not mean the trait "is genetic" in totality.  Most behavioral traits have a combination of genetic and environmental (be it developmental, social, toxicological, or else wise environmental) factors.  There's also a new factor discovered recently that lies somewhere in between: epigenetics.  I can't be certain, but I'd think this would appear in monozygotic similarities, probably confounding results a bit.


Origin of group-level statistics in psychology and cognitive neuroscience

What you are actually asking about is the debate surrounding the question:

Can psychological quantities be measured?

Up until about 1800 psychological questions where discussed by philosophers. A separate psychological discipline did not yet exist. Answers to questions relating to perception, emotion and cognition where attempted on the basis of religious beliefs, philosophical tradition and unsystematic observation and introspection.

Over the course of the eighteenth century, the body-mind dualism was slowly being resolved, which allowed first physiologists and then physicists over the course of the nineteens century to begin to apply their methodology of experimenting with plants and animals and mathematical principles, as they had been developed within the natural sciences, to psychological questions. In the middle of the nineteenth century, the first psychological institutes were founded, the first by Wundt (in Leipzig, Germany), and the discipline of psychology came into existence.

Looking at the history of psychology, you will realize that while psychological questions are as old as humanity, the academic discipline of psychology came into existence when scholars began to measure, i.e. quantify, the psyche. This was in accordance with the rise of the natural sciences during the Enlightenment and their dominance over our whole worldview (almost?) until today.

In his classice monography, Psychometric Methods (1936), J. P. Guilford writes:

  The progress and maturity of a science are often judged by the extent to which it has succeeded in the use of mathematics. The “psychometric methods” are procedures for psychological measurement. Measurement means the description of data in terms of numbers and this, in turn, means taking advantage of the many benefits that operations with and mathematical thinking provide.

Thus, while psychological questions have traditionally been considered in the humanities and arts, the academic discipline of psychology has been created and finds its home within the natural sciences and shares their basic approach of quantitative measurement and statistical analysis. Philosophical and artistic "psychology" have continued to exist parallel to institutionalized academic psychology and have given rise to psychoanalysis (Freud), humanistic psychology (Rogers) or critical psychology (Holzkamp), among others.

The principles and standards of psychological experimentation and statistical analysis as we know them today where not discovered instantaneously but developed and refined until the middle of the twentieth century. In 1936 Guilford found that the natural sciences lacked a common theory of measurement:

  Measurement in the physical sciences has come so naturally that in that connection little thought has had to be given to what measurement really is. There are some physical scientists who maintain that what is called measurement in psychology is not measurement at all. It is true that the term measurement is sometimes defined in such a way that it does not apply to most of the operations in psychology commonly known as measurement. Definition of an abstract term such as measurement is an arbitrary matter, however, and psychologists will either define it to cover what they are doing under that concept or they will invent a new term for what they are doing with numbers and arithmetical operations. Fortunately, measurement can be defined sufficiently broadly to include the operations known as psychological measurement.

Four years before this statement, in 1932, the British Association for the Advancement of Science had established a committee of scientists that should consider the problem of measurement in the empricial disciplines. The committee was especially asked to resolve the question, whether a measurement of sensation was possible. The answer to this question would decide wether psychology was a natural science coequal to physics or chemistry. Psychologist S. S. Stevens (1946) writes about the committee's discussions:

  For seven years a committee of the British Association for the Advancement of Science debated the problem of measurement. Appointed in 1932 to represent Section A (Mathematical and Physical Sciences) and Section J (Psychology), the committee was instructed to consider and report upon the possibility of “quantitative estimates of sensory events” — meaning simply: Is it possible to measure human sensation? Deliberation led only to disagreement, mainly about what is meant by the term measurement. An interim report in 1938 found one member complaining that his colleagues “came out by that same door as they went in,” and in order to have another try at agreement, the committee begged to be continued for another year. For its final report (1940) the committee chose a common bone for its contentions, directing its arguments at a concrete example of a sensory scale. This was the Sone scale of loudness (S.S. Stevens and H. Davis, Hearing. New York: Wiley, 1938), which purports to measure the subjective magnitude of an auditory sensation against a scale having the formal properties of other basic scales, such as those used to measure length and weight. Again the 19 members of the committee came out by the routes they entered, and their views ranged widely between two extremes. One member submitted “that any law purporting to express a quantitative relation between sensation intensity and stimulus intensity is not merely false but is in fact meaningless unless and until a meaning can be given to the concept of addition as applied to sensations.”

So, while the committee could not agree on the question wether sensation can be measured, they made it clear that an empirical equivalent to arithmetic addition would constitute measurement. This refers to the foundation of the measurement of physical quantities by Hermann von Helmholtz (1887) and defined axiomatically by Hölder (1901).

I don't want to go into the details of this argument, because it goes beyond the scope of this question. In short, Helmholtz sought to base measurement on the empirical comparison of so-called "extensive quantities", for example physical length or mass. He correlated arithmetic addition to physical combination (e.g. lineal apposition of staves to measure lengths) and the equality of two numbers to a method of "physical comparison", for example the comparison of weights on a beam balance).

How these principles of extensive measurment can be applied in psychology, and if it should, has been heavily debated, and different "test theories" have been developed, such as classical test theory, latent trait theory, or the theory of knowledge spaces. Foundational texts for a representational theory of measurement are those by Krantz, Luce, Suppes, and Tversky (1971, 1989, 1990) and Robers (1979), if you are interested in this aspect. All books feature some general introduction but require mathematical understanding to follow.

This requirement of a broad and deep understanding of mathematics is the reason why all psychology looks the same to you.

Most currently publishing psychologists have only a superficial understanding of methodology. Gigerenzer, Krauss and Vitouch (2004) explain some of the methodological shortcomings and mistakes:

  One of us once had a student who ran an experiment for his thesis. Let us call him Pogo. Pogo had an experimental group and a control group and found that the means of both groups were exactly the same. He believed it would be unscientific to simply state this result; he was anxious to do a significance test. The result of the test was that the two means did not differ significantly, which Pogo reported in his thesis.

  In 1962, Jacob Cohen reported that the experiments published in a major psychology journal had, on average, only a 50 : 50 chance of detecting a medium-sized effect if there was one. That is, the statistical power was as low as 50%. This result was widely cited, but did it change researchers’ practice? Sedlmeier and Gigerenzer (1989) checked the studies in the same journal, 24 years later, a time period that should allow for change. Yet only 2 out of 64 researchers mentioned power, and it was never estimated. Unnoticed, the average power had decreased (researchers now used alpha adjustment, which shrinks power). Thus, if there had been an effect of a medium size, the researchers would have had a better chance of finding it by throwing a coin rather than conducting their experiments. When we checked the years 2000 to 2002, with some 220 empirical articles, we finally found 9 researchers who computed the power of their tests. Forty years after Cohen, there is a first sign of change.

  Editors of major journals such as A. W. Melton (1962) made null hypothesis testing a neces- sary condition for the acceptance of papers and made small p-values the hallmark of excellent experimentation. The Skinnerians found themselves forced to start a new journal, the Journal of the Experimental Analysis of Behavior, to publish their kind of experiments (Skinner, 1984, p. 138). Similarly, one reason for launching the Journal of Mathematical Psychology was to escape the edi- tors’ pressure to routinely perform null hypothesis testing. One of its founders, R. D. Luce (1988), called this practice a “wrongheaded view about what constituted scientific progress” and “mind- less hypothesis testing in lieu of doing good research: measuring effects, constructing substantive theories of some depth, and developing probability models and statistical procedures suited to these theories” (p. 582).

  The student, the researchers, and the editors had engaged in a statistical ritual rather than sta- tistical thinking. Pogo believed that one always ought to perform a null hypothesis test, without exception. The researchers did not notice how small their statistical power was, nor did they seem to care: Power is not part of the null ritual that dominates experimental psychology.

The articel runs on and explains what the p-value can and cannot do (read it, if you are a psychologist). I only quoted the beginning in length to show you that a methodologically savvy minority among psychologists believes that the majority of scholars publishing in their discipline does not know what they do. They follow a "ritual" of blindly applying the same methods to all problems, thus hampering the progress of the discipline and reducing the value of their findings.

Nevertheless, while widely ignored, progress has been made (see my brief remarks about different theories of measurement above).

If you want to learn more about the development of psychology as a natural science, grab any book on the history of psychology from a nearby university library. Make sure you pick one that starts at least in the nineteenth century, but for a better understanding it is necessary to look back until Leibnitz and his contemporaries.

If you want to learn more about measurement in psychology, books such as Joel Michell's Measurement in Psychology: A Critical History of a Methodological Concept provide a good introduction. I have not read any of those books and cannot recommend one. My own knowledge (and the summary given here) stems from a couse in psychometrics I took while studying psychology.

To summarize, academic psychology uses experimentation and statistical analysis because it is a natural science and adheres to the basic principles that define these disciplines. The belief that the universe is probabilistic (and events are distributed and these distributions can be described through arithmetic means and such) rules most of the natural sciences today and is not unique to psychology.

Beyond this unifying foundation, the different fields of psychology have quite different goals and methods. For example, general psychology (including the psychology of perception) is not interested in the distribution of a trait (such as intelligence) across a population, but in understanding, for example, the principles that govern learning in all individuals.

It is not true that experiments have to be performed on a group of subjects. In the psychology of perception, for example, which does not deal with interspecies differences but with the basic principles of human psychology, it is common to use only one single subject, because it is assumed that certain aspects of perception, such as trichromatic vision, are the same in all members of the population and can be investigated in any (healthy) individual. But of course this one test subject has to perform multiple trials, which are then analysed statistically.

Statistical analysis and the application of mathematics to reality itself goes back to ancient times. Bakker (2003) finds predecessors of contemporary statistical concepts as far back as ancient Indian texts:

  In an ancient Indian story, Rtuparna estimated the number of leaves and fruit on two great branches of a spreading tree (Hacking 1975). He estimated the number on the basis of one single twig, which he multiplied by the estimated number of twigs on the branches and found a number, which after a night of counting turned out to be very close to the real number.

Aristotle, in the Nichomachean Ethics calculated the mean as "a point equally distant from either extreme", and this was developed further by Ticho Brahe and others until Legendre introduced the least squares method, that we use today, in 1805.

If you want to know about the history of statistics, that is beyond the scope of this site.

The answer to your question in detail:

Why group level statistics?

Because there is no other way of measurement. As a physicist you know that every measurement is a sample from a population. If, for example, you measure weight, each measurement of the same weight will be different, if your scale is sensitive enough. You will then calculate the distribution and its characteristics (mean, slope, range etc.) to describe that distribution. If you do only one measurement, then that is because the differences are negligible for your purpose (e.g. human body weight) or measurement is too expensive and time consuming.
Since when group level statistics?

The ancient Indian example shows that group level statistics has been done since the dawn of time: a representative sample of leaves where drawn from a tree to understand the whole population of leaves. Of course that Indian "mathematician's" estimations where primitive, since the relevant mathematics hadn't been invented yet. The arithmetic mean was defined as late as 1805. But the basic idea and principles are identical to ours: estimate the properties of a population from a representative sample.
Why group level statistics in psychology?

The reason is not a psychological but a methodological one, and it is given in the quote by Guilford: It is the dominating belief of our culture that a true science must employ mathematics. So as soon as psychology was created as a separate scientific discipline, it had to use statistics. Otherwise it would have remained an area of speculation, in the eyes of the scientific community.
Since when did psychology employ group level statistics?

Building on the groundbreaking work of Ernst Heinrich Weber, Gustav Fechner defined the absolute threshold as the statistical mean of all threshold values in the method of limits in his work Elemente der Psychophysik (1860). Fechner also developed the notion of the median (in 1878).

But my answer describes that the use of mathematical methods in psychology was not so much a singular event that affected the rest of the science like an explosion, but a gradual process that happened as psychology was slowly detached from philosophy and grew into a natural science from around 1800 to around 1950, when the process was largely finished (with Stevens' publication).

And again, you must understand that the theory of measurement – and even statistics itself! – was in development in all of the natural sciences at the same time. For example, the arithmetic mean was defined in 1805, Legendre published the least squares method in the same year, and Gauss defined the normal distribution and maximum-likelihood estimation in 1809. This ongoing development was why the British committee on measurement was set up in 1932: because no satisfying theory of measurement had been created until then!
Why the popularity of the mean?

Because most psychologists don't understand statistics well enough to do more than that.
Why population average instead of effects that are present in every single individual in the population, or a specific sub-population?

You obviously did not read a lot of psychological texts. The field of general psychology focusses on effects that are present in every single individual and often does experiments of one proband. Only the field of differential psychology explores the distribution of traits among the population. Other fields look at sub-populations (e.g. children or old people, psychiatric patients, workers of a certain occupation, and so on).

In the history of psychology, the first studies (all through the 1800s) explored general psychology: perception, cognitition, memory. Beginning around 1900, differential psychology began first with the measurement of intelligence, and then the study of medical psychology in psychiatric patients. Around the First World War occupational psychology began to study work behaviour and pedagogical psychology began to apply the findings to the training of future workers and soldiers. Workers and soldiers are groups, so there is also an economic and political reason for group-focussed psychology. Advertising and Human Resources are still today the largest areas of psychology beside clinical psychology, which partially explains the continuing focus on population based studies.

Finally, of course there are scholars that employ a more refined statistics and do not focus on the mean so much, and there are scholars that believe there are aspects of human psychology that are not covered by a statistical approach. If you are interested in them, go deeper into psychology or create your own alternative methodology that represents what you believe about the human psyche.

All of this is of course my personal opinion. I am no historian of psychology and do not have the overview to judge the correctness of my interpretation. I used the small sample of publications that my professor for methodology provided and that I hope is representative. From this sample, I estimated the history of psychology, and my estimation may, of course, be wrong.

Sources:

Bakker, A. (2003). The early history of average values and implications for education. Journal of Statistics Education, 11(1), 17-26.
Fechner, G. Th. (1860). Elemente der Psychophysik [Elements of Psychophysics]. Leipzig: Breitkopf und Härtel.
Gigerenzer, G., Krauss, S., & Vitouch, O. (2004). The null ritual. The Sage book of quantitative methodology for the social sciences, 391-408.
Guilford, J. P. (1936). Psychometric Methods. New York: McGraw-Hill.
Helmholtz, H. (1887). Zählen und Messen erkenntnistheoretisch betrachtet. In Philosophische Aufsätze Eduard Zeller zu seinem fünfzigjährigen Doctor-Jubiläum gewidmet. Leipzig: Fues.
Hölder, O. (1901). Die Axiome der Quantität und die Lehre vom Mass". Berichte über die Verhandlungen der Koeniglich Sächsischen Gesellschaft der Wissenschaften zu Leipzig, Mathematisch-Physikaliche Klasse, 53, 1–46.
Krantz, D.H., Luce, R.D., Suppes, P. & Tversky, A. (1971). Foundation of measurement. Vol. I. Additive and polynomial representations. New York: Academic Press.
Luce, R.D., Krantz, D.H., Suppes, P. & Tversky, A. (1990). Foundation of measurement. Vol. III. Representation, axiomatization, and invariance. New York: Academic Press.
Roberts, F.S. (1979). Measurement theory with applications to decisionmaking, utility, and the social sciences. Reading: Addison-Wesley.
Stevens, S. S. (1946). On the theory of scales of measurement. Science, 103, 667-680.
Suppes, P., Krantz, D.H., Luce, R.D. & Tversky, A. (1989). Foundation of measurement. Vol. II. Geometrical, threshold, and probabilistic representations. New York: Academic Press.


What percentage of those diagnosed with schizophrenia didn't have brain abnormalities?

This ENIGMA study did not assess brain abnormalities at an individual level. Rather, it examined if the volumes of a range of subcortical brain structures differed between patients with schizophrenia and healthy control subjects at the group level, using a meta-analytic approach. The term "brain abnormalities" might be misleading in this context: The study was not about the type of brain abnormalities that would be detectable by a neuroradiological exam (for a study focusing on this, see Sommer et al, 2013, Schizophrenia Bulletin, doi: 10.1093.schbul.sbs037). It is therefore not possible to determine the percentage of patients who had brain abnormalities from the study.


Is it possible to master two different typing keyboard layouts?

Observational points:
It would be straightforward to point to a person who has mastered more than one keyboard layout (e.g., some of the people here). So, yes, it is possible. From my own personal experience, I can point to my use of both Vim keyboard shortcuts for editing and regular OSX/Windows keyboard shortcuts. This is certainly possible.

But I'd prefer to focus on the scientific principles that underly such a capacity.

Scientific principles:

There are a number of scientific principles operating in this context.

Negative and positive transfer
Principles of task consistency and complexity

In general transfer of skill from one domain to another depends on the degree of consistency between the two skills. This is a broad concept. Certainly the mapping between inputs and outputs is a big part of this (i.e., key press and letter). But it could also include a range of broader conceptual and psychomotor routines.
Thus, positive transfer occurs when you can take the skill on one task to improve your performance in another. Negative transfer occurs when your performance on one task suffers as a result of learning a different task. In general positive transfer is much more powerful than negative transfer.

Applying these principles to converting from QWERTY to DVORAK

Let's say that you have a person who has learnt the QWERTY keyboard layout and can type 80 words per minute. They decide that they want to learn DVORAK. What would we expect from a skill acquisition perspective?

The new keyboard layout (DVORAK) shares many consistent cognitive and psychomotor elements with the original layout (QWERTY). The basic motor actions of pressing individual keys are identical. Many other cognitive skills around the concept of typing are also the same. However, the actual specific key-to-letter mappings will be new. Furthermore, learning to type involves building up specific motor patterns around common sequences of letters and some of these will also be new.

The net result will be that learning to efficiently use DVORAK should take a fair bit of time. However, the learning curve should be massively faster than learning how to touch type the first time. Thus, in a basic sense, the main limitation to learning to type using two keyboard layouts is that it just takes more time than to learn one layout. And generally, you will be better at one layout than the other, so why bother learning two layouts unless perhaps you are transitioning to a new layout for the long term.

Based on general principles of cognitive transfer, generally knowing QWERTY will make DVORAK easier to learn. So most of the transfer will be positive. It is likely that there will be some accidental applications of QWERTY when you are in DVORAK and vice versa. Such errors can be minimised if you can create stimuli in your task environment that clearly communicates the appropriate mapping (e.g., use it on particular computers). The general concept in skill acquisition is that a single stimulus-response pairing is easier to manage, but over time you will learn to apply contextual cues to choose the correct stimulus-response options.

Another general principle for psychomotor skills is that forgetting is slower and relearning is quicker than for a lot of cognitive skills (Rosenbaum et al, 2001). Thus, people are likely to be able to retain and get back up to speed on a previously learnt keyboard layout after a period of using a newer layout.

References

If you're interested in reading more, you might want to check out some of Philip Ackerman's early work on skill acquisition where he talks about consistency and complexity.

There's also a large literature that has studied the cognitive psychology of learning to touch type.

Ackerman, P. L. (1989). Within-task intercorrelations of skilled performance: Implications for predicting individual differences? A comment on Henry & Hulin, 1987.
Ackerman, P. L. (1988). Determinants of individual differences during skill acquisition: cognitive abilities and information processing. Journal of experimental psychology: General, 117(3), 288.
Rosenbaum, D. A., Carlson, R. A., & Gilmore, R. O. (2001). Acquisition of intellectual and perceptual-motor skills. Annual review of psychology, 52(1), 453-470.
Yechiam, E., Erev, I., Yehene, V., and Gopher, D. (2004). Melioration and the transition from touch-typing training to everyday use. Human Factors, 45, 671-684.


Does verified evidence for Freudian repression of traumatic memories exist?

I find this question very interesting, for this reason i did some digging.

Short answer

Yes, there're many studies about neurobiological implication of "repressed memories" and they underline how informations do not disappear. Through the
mechanisms of complex neural processes, it is obvious that this information is exposed to various kinds of cellular and molecular operations. These processes can not be deleted. The brain never “forgets” at the cellular and molecular levels.(Mehmet Emin Ceylan, M.D., Aslıhan Sayın, M.D., 2012)

Long answer

In recent years, an effort has been made to identify the underlying neuroanatomical,
neurophysiological and molecular underpinnings of psychoanalytical concepts like repression. The view that, every mental action is caused by a change in an
identifiable neural system (or vice versa), is not surprising. Any decision we make, any
feeling we have, is the result of activity in neural networks and molecular-level structures
such as receptors, messenger systems, neurotransmitters etc. that are involved in the process
of neurotransmission. Moreover, this fact applies not only to conscious mental activities, but
also to mental activities that are not conscious. Everything that goes on in the brain affects our
mind, but we are not consciously aware of everything that goes on in our mind. This situation
is described by Freud as the equivalent of an unconscious mental process.

We know that repression is a defense mechanism that plays a role in the formation of
unconscious mental activities and processes. Thus, it is reasonable to assume that repression
must have a neural mechanism. The technology of Freud’s time was incapable of explaining
the biological correlates of the mental processes described by his psychoanalytic theory.
Today’s technological capabilities, advances in brain imaging methods, advanced methods in
brain electrophysiology and molecular biology promise an opportunity to observe and analyze
these mechanisms.

Neural representation of the external event is bound by hippocampus
Then, the LTP (long-term potentiation) process provides the neural mechanisms of consolidation, in which a
particular external event becomes a lasting memory, which is the basis for long-term memory.
While the hippocampus controls consciouss memory,the amygdala is required for the
unconsciously associated vegetative reaction (Bechara et al., 1995).
fMRI studies in post-traumatic
stress disorder patients indicate that recall of traumatic events is associated with an increased
activation of the amygdala and a reduced activation of the hippocampus
It is reasonable to assume that repression
must have a neural mechanism: The following study suggests that dorsolateral prefrontal cortex,
and especially its caudal part plays a major role for repression of childhood traumatic events.
Possible molecular mechanism of memory erasure in repression is long term depression of
glutamatergic neurotransmission between prefrontal cortex- thalamus- limbic system.

REFERENCES

Neurobiology of Repression

Bechara, A., Tranel, D., Damasio, H., Adolphs, R., Rockland, C., Damasioa, A.R.,
1995. Double dissociation of conditioning and declerative knowledge relative to the amigdala
and hippocampus in humans. Science 269, 1115-1118.


Causality regarding neurotransmitter imbalance and depression

I have what is mostly a frame-challenge to your question as an answer: the simple "neurotransmitter imbalance" hypothesis is a bit outdated, and it hasn't been strongly influential in a research context for a very long time.

Rather, it is an extremely oversimplified way to try to explain that there are brain differences involved in depression: that it's a real and physical disorder rather than something "made up" or "all in the head". This message might be useful for patients in explaining that their symptoms are not imaginary or something to just "get over", and also for pharmaceutical marketing of those medications. It may also cause harm (see Kemp et al 2014).

The hypothesis is originally based on studies that showed both a) that drugs impairing serotonin signalling could create depressive symptoms in animal models, and b) that drugs like selective serotonin reuptake inhibitors (SSRIs), which (at least initially) increase synaptic availability of serotonin, could treat depressive symptoms. Since then, more work shows that it is very questionable to consider reduced levels of monoamines like serotonin purely causative for depression, because depletion of such monoamines fails to produce depressive symptoms in healthy subjects (France et al 2007 review several such studies).

However, other neurotransmitters are also involved, and serotonin itself acts through numerous receptor subtypes (even completely different families), and many of these influence levels of other neurotransmitters as well. Levels of glutamate, dopamine, and norepinephrine are also both implicated in depression, but like with serotonin there is no clear, simple story.

In the brain, it's not just how much of a substance is present, but where it is released, when it is released, and in what pattern it is released. The same neurotransmitter in different brain areas can have different or even opposite effects. A neurotransmitter released 100 times in 1 second or 100 times in 100 seconds can have different or even opposite effects.

There is also a strong likelihood that depression and related conditions including anxiety disorders are not specific conditions but rather umbrella descriptions for a host of different brain dysfunctions. If there was a simple story, it wouldn't be nearly as complicated to treat.

France, C. M., Lysaker, P. H., & Robinson, R. P. (2007). The" chemical imbalance" explanation for depression: Origins, lay endorsement, and clinical implications. Professional Psychology: Research and Practice, 38(4), 411.

Kemp, J. J., Lickel, J. J., & Deacon, B. J. (2014). Effects of a chemical imbalance causal explanation on individuals' perceptions of their depressive symptoms. Behaviour research and therapy, 56, 47-52.

Lacasse, J. R., & Leo, J. (2005). Serotonin and depression: a disconnect between the advertisements and the scientific literature. PLoS medicine, 2(12).

Leo, J., & Lacasse, J. R. (2008). The media and the chemical imbalance theory of depression. Society, 45(1), 35-45.


Can dendrite spines fire action potential toward the soma?

This question shows a good amount of intuition.  It is true that the signal is generally thought to diffuse passively.  However, active propagation of dendritic signals is certainly an important property.  As opposed to the axon, where the action potential is generated by voltage-gated sodium (Na+) channels, in the dendrites, the voltage gated channels are calcium (Ca2+) channels (VGCC -- voltage gated calcium channels) or non-specific cation (Na+, K+, and Ca2+) channels such as the NMDA channel.  The voltage gated nature of these excitatory channels leads to a positive feedback effect similar to that of the action potential itself. However, the time course of these signals is much slower: on the order of 10s to 100s of milliseconds, as opposed to the 1ms time scale of the action potential.  These dendritic spikes or calcium spikes or plateau potentials can lead to firing of bursts of action potentials.

As a side point, action potentials generated in the soma can actually be propagated backwards (backpropagating action potentials) into the dendrite using the same voltage gated channels.  http://www.ncbi.nlm.nih.gov/pubmed/8107777

References
Schiller, J. et al. (2000) NMDA spikes in basal dendrites of cortical pyramidal neurons. Nature 404, 285–9

Major, G. et al. (2008) Spatiotemporally graded NMDA spike/plateau potentials in basal dendrites of neocortical pyramidal neurons. J. Neurophysiol. 99, 2584–601

Cai, X. et al. (2004) Unique roles of SK and Kv4.2 potassium channels in dendritic integration. Neuron 44, 351–64

Wei DS, Mei YA, Bagal A, Kao JP, Thompson SM, Tang CM (2001) Compartmentalized and binary behavior of terminal dendrites in hippocampal pyramidal neurons. Science 293:2272–2275.

I actually have written a paper myself on the potential usefulness of dendritic plateau potentials in working memory:
Sanders, H. et al. (2013) NMDA and GABAB (KIR) Conductances: The “Perfect Couple” for Bistability. J. Neurosci. 33, 424–429  http://www.jneurosci.org/cgi/doi/10.1523/JNEUROSCI.1854-12.2013


Is the amount of learning modulated by reward transmitters?

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.


Are there some discussions about Buddhism in science?

Some resources:

Wikipedia has a whole page for Buddhism and science in specific and Cognitive science of religion in general.
Alan Wallace's Buddhism and Science
Tricycle's The Scientific Buddha. Tricycle is a Buddhism-oriented magazine that is quite popular
Mind and Life Institute. One of its founder is Dalai Lama, and it hosts MindRxiv preprint. You can find many preprints in the field there
The mindfulness technique is widely used in therapy


Where to get psychology assessment resources to put into my website?

There's nothing too deep about IPIP scoring. It just uses the standard Likert scale.

From https://ipip.ori.org/newScoringInstructions.htm

  Converting IPIP Item Responses to Scale Scores

  Here is how to score IPIP scales:

  For + keyed items, the response "Very Inaccurate" is assigned a value of 1, "Moderately Inaccurate" a value of 2, "Neither Inaccurate nor Accurate" a 3, "Moderately Accurate" a 4, and "Very Accurate" a value of 5.

  For - keyed items, the response "Very Inaccurate" is assigned a value of 5, "Moderately Inaccurate" a value of 4, "Neither Inaccurate nor Accurate" a 3, "Moderately Accurate" a 2, and "Very Accurate" a value of 1.

  Once numbers are assigned for all of the items in the scale, just sum all the values to obtain a total scale score.

  Easy, no? (If you are having problems, you might contact the IPIP consultant. [j5j@psu.edu])

And they do have a scoring key for the 50-question version meaning it links questions to Big Five factors; I'm not quoting that whole thing there, but here's a snippet:

Big-Five Factor Markers

Factor I (Surgency or Extraversion)

10-item scale (Alpha = .87)
+ keyed
    Am the life of the party.
    Feel comfortable around people.
    Start conversations.
    Talk to a lot of different people at parties.
    Don't mind being the center of attention.

– keyed
     Don't talk a lot.
     Keep in the background.
     Have little to say.
     Don't like to draw attention to myself.
     Am quiet around strangers.

Factor II (Agreeableness)

10-item scale (Alpha = .82)
+ keyed
    Am interested in people.
    Sympathize with others' feelings.
    Have a soft heart.
    Take time out for others.
    Feel others' emotions.
    Make people feel at ease.

– keyed
    Am not really interested in others.
    Insult people.
    Am not interested in other people's problems.
    Feel little concern for others.

And so on for the other three factors. Alpha refers to Cronbach alpha. It's not relevant for your purposes, but only for a reliability evaluation of the test-design itself. (The 100-question variant, also contained in that parge, obviously has higher Alpha.)

If you want a facet-level test, which further subdivides each of the Big Five factors, look at their 120-question NEO PI-R; it has a similar key. They also have a HEXACO key, which adds a sixth main factor (also faceted).

I'm not sure what you mean by "reporting standard". I suspect you want to relate the raw scores to population averages and standard deviations. To get such tables you need to read the original papers on which is based. Here's the one for HEXACO, for instance (this one is even broken down by gender):

The IPIP  master key page has a list of references in which you can find the publication for the specific test you are interested in.

The initial IPIP test you mentioned/found (the 50-q one) is based on Goldberg's paper, but that one doesn't seem to contain either the IPIP-modified questions nor even population level means and standard deviations. (The population-based statistics are prone to change a bit if the questions are altered.) So if you pick a test like that you need to gather a sample of subjects first, have them complete the questionnaires, and then compute your own mean & variance distribution tables! Experimental psychology is (hard) work at times.

Luckily, there's a newer paper, on the mini-IPIP (just 20 q's), (also has key available) which also reports that population data for the older 50-q test.

N.B.: normally a percentile in the distribution would be reported to the user; see this math.SE question for the conversion from raw score to percentile in the normal distribution; basically use a Z-table.


How to view or download an open access article from ARVO journals?

The paper you are linking to is an abstract presented on the Vision Sciences Society Annual Meeting of 2011. Study abstracts are submitted to the conference organizers and often appear in the conference program and/or on the conference web site. They describe the work that will be/has been presented as an oral or poster presentation on a conference. Often the abstract is the only written record that remains of a conference prezzo. In other words, the abstract you are seeing is the paper itself, there is no further material to be downloaded, which explains the absence of the download button. If you click on the specific 2011 issue, you'll see hundreds of prezzo abstracts listed there, including yours. On the website of VSS there's unfortunately only information about the last conference held, I believe in May 2020.
You can contact the study authors and ask if they are willing to share the poster or the slides of the prezzo. In my experience, authors are often happy to share their research. Perhaps the results have been published in a journal paper in the meantime.


When to use standard versus moderator regression techniques for the most parsimonious approach?

You write:

  When controlling for age, gender and anxiety, participants high in sense of humour will have higher life satisfaction.

This is standard regression. Predictors that are control variables are the same as any other predictors, it's just that their inclusion in the model is mostly there to facilitate a desired interpretation of a focal predictor.

  Also, when excluding variables of age and gender, I predict that the negative association between anxiety and life satisfaction will be stronger for those with low sense of humour ratings.

Here you have described a moderation hypothesis.
i.e., in regression terms, you might express it like this:

lifesat ~ anxiety * humour

However, technically, you have not assigned anxiety or life satisfaction a particular status as the outcome variable. Whether you "exclude age and gender" is irrelevant to the status of the hypothesis as a moderation hypothesis.

You ask specifically:

  I feel that for most of these questions, the answers could be found using an SMR, and the last question, with an MMR, but is there a simpler and more parsimonious way to do this? Can I gather the data for the first few questions from the MMR analysis, for example?

Don't be afraid to run several regression models. Ultimately, a moderator regression is simply a model with an interaction term. Adding predictors generally alters the regression coefficients for other predictors (an exception would be for orthogonal variables, such as in experiments).


Why is a lack of response to punishment in adults considered significant in diagnoses?

In response to your first inquiry, lack of response to punishment, in some cases, may suggest the lack of conscience/fear. Many are diagnosed or have the symptoms of a sociopath; being that they think themselves as untouchable, greater than anything/anyone outside of themselves; they don't feel fear the way "norms" do, nor do they feel remorse for what they inflict on others. Therefor, they will find "reason" for any and all wrongdoing they inflict.
  So far as your second question, it is not so much that it is "assumed" that most people will respond in an "expected" way to punishment. Rather, the  individual that has been tested in the same arena as a diagnosed sociopath vs. the majority of people who feel remorse, exude morals and personal responsibility.

http://www.cassiopaea.org/cass/sanity_1.PdF

"The Sociopath Next Door"- Martha Stout

http://www.npr.org/2013/06/19/193099258/inside-the-mind-of-a-sociopath
 I hope this is some semblance of an answer for you.

Update:
 In your words, sociopathy and psychopathy are speculative.
  All science, on the other hand is proven by trial and error. Subjects being tested and who bear on the "normal" end of the spectrum, is named so by the trial and error which is performed and proven from past subjects.
   Moving on, I will say that, speculatively, the majority of people will not hold up a bank, steal money from petty cash at their place of employment, or commit murder, due to their morals, conscience, or fear of getting caught due to the punishment they may receive.
   However, if there is NO fear, NO morals, NO conscience, there may be room for diagnosis.
  A person may feel they have done nothing wrong and that their actions are justified. Everyone has reasons for doing what they do. But the majority of people tend to feel remorse when they cause others undue comfort, cheated anotherin an extreme circumstance, or was the cause of a terrible negative outcome. For a person to feel they have done nothing wrong and that their punishment is unjust, happens every day. But it's the one who does NOT feel, nor  take personal responsibility(the blame is never theirs) who may, over repeated instances, be diagnosed with a form of psychosis.


What hidden latent variables could be responsible for the high correlation between WORDSUM and IQ?

I'd probably reframe your question to be slightly broader, such as "why do vocabulary tests correlate so highly with estimates of general intelligence (i.e., g)?".

Anyway, here are a few thoughts:

Verbal ability measures, including vocabulary tests, are often part of IQ tests. Thus, some of the correlation may flow from our conceptualisation of intelligence as requiring verbal aptitude.
Ability tests tend to intercorrelate; these correlations are generally greater within a domain (e.g., verbal, spatial, etc.), but even across domains, correlations are observed. Thus, whatever drives correlations between any ability test and general intelligence may also partially explain the vocabulary-IQ correlation. However, this isn't the complete story, because certain tests (from memory, e.g., Raven's Progressive Matrices and Vocab) correlate more with g than others.
People with greater intelligence may be more likely to seek out verbal stimuli, be provided with verbal stimuli, and retain and understand verbal stimuli, all processes which over many years would accumulate into a greater vocabulary. Similarly perhaps, relatively stable environmental factors might simultaneously increase intelligence and vocabulary.

I'd be keen to read any specific studies which involved a vocabulary based intervention and see whether (a) this was successful in increasing vocabulary test scores, and (b) whether the intervention lowered the correlation with vocabulary and intelligence.


What is the neurological basis of bipolar disorder?

The exact cause of bipolar disorder is unknown (source: NHS). It is believed that there are a number of interacting physical, environmental and social factors that may cause bipolar disorder to develop.

Chemical imbalance in the brain: Bipolar disorder is believed to be the result of chemical imbalances in the brain, and noradrenaline has been implicated (Young et al., 1994). Noradrenalin (norepinephrine) in the central nervous system regulates arousal and modulates reward circuitry and positive reinforcement. Many antidepressant drugs target noradrenergic projections to alleviate symptoms of depression (Trevino et al, 2012). There is evidence that episodes of mania may occur when levels of noradrenaline are too high, and episodes of depression may be the result of noradrenaline levels becoming too low (source: NHS). Reduced serotonin levels have been found too, which is a general hallmark of depression and not specifically related to bipolar disorder (Young et al., 1994).
Genetics: bipolar disorder tends to run in families (Lichtenstein et al., 2009. The family members of a person with the condition have an increased risk of developing it themselves. However, no single gene is responsible for bipolar disorder. Instead, a number of genetic and environmental factors are thought to act as triggers (sources: NHS and Mayo Clinic).
Triggers: A stressful circumstance or situation often triggers the symptoms of bipolar disorder, e.g., physical, sexual or emotional abuse, or
the death of a close family member. These life-altering events can cause episodes of depression at any time in a person's life. Bipolar disorder may also be triggered by physical illness, sleep disturbances, overwhelming problems in everyday life (sources: NHS and Mayo Clinic).

References
- Lichtenstein et al., Lancet (2009); 373(9659): 234–9
- Trevino et al, Encyclopedia of Human Behavior (2012), 2nd ed.
- Young et al., Biol Psychiatry (1994); 35(2): 121–7


Whether to ask satisfaction and importance questions for each item in a survey?

Computing overall satisfaction

There is discussion in the literature about whether measures of overall satisfaction should be calculated as some form of weighted composite of facet satisfaction where weights are derived from importance ratings.
These debates have been applied to various types of satisfaction including life, job, and customer. In this context, it does not seem like weighting by importance makes much difference, and it may even be detrimental.

For examples, Trauer et al (2001) state that:

  Many Quality of Life (QoL) instruments ask respondents to rate a
  number of life domains in terms of satisfaction and personal
  importance, and derive weighted satisfaction scores by multiplying the
  two rat- ings. This paper demonstrates that this practice is both
  undesirable and unnecessary. QoL domains are selected on the basis of
  their inherent importance, rendering separate importance rating
  partially redun- dant. Weighted scores present difficulties in
  interpretation. Further, we show that multiplicative composites have
  undesirable psychometric properties. There is evidence that
  multiplicative composites have little or no advantage over unweighted
  ratings in correlational or predictive studies. Apart from the face
  validity and the intuitive appeal of multiplying satisfaction ratings
  by importance ratings, there appear to be no sound reasons for doing
  so, and several good reasons not to do so.

A similar critique of importance ratings in the job satisfaction domain can be seen in Blood (1971).

Nonetheless, this all assumes that importance measurement is a means for  forming an overall composite. In some instances, measurement of importance is of substantive interest. Trauer et al (2001) acknowledge this when they write:

  It is not suggested that the assessment of the importance of domains
  of satisfaction is inconsequential. It has been shown that domains
  that are closer to the personal core (e.g. health, marriage, family)
  are typically judged as more im- portant than more peripheral domains
  (e.g. membership of organizations)...

Study of mean importance ratings

Importance ratings can be used to assess average perceptions of importance which might inform causal hypotheses regarding what is influencing satisfaction.

Take for example, Rice et al (1991) among many other things, they report importance ratings of various job facets. Among other things the authors asked 97 employed college students to rate

  facet importance on a 9-point scale with two verbal
  anchors: not at all important and extremely important (e.g., "How
  important to you is the amount of opportunity for promotion?").

If we sort the results reported in Table 1 by importance we see the following:

Job Facet                     Mean Importance
Hourly pay (dollars)              7.4
Hours per week                    7.3
Control over schedule             7.3
Opportunity to learn skills       6.7
Decision making                   6.4
Promotion opportunity             6.3
Mental effort required            6.1
Conversation with co-workers      6.0
Customer or client contact        5.7
Physical effort required          5.4
Supervisor contact                5.3
Commuting time (minutes)          4.3

This is presumably an interesting empirical finding in itself.

Relationship between importance and satisfaction

Some researchers have explicitly studied the relationship between importance and satisfaction to see whether there is a relationship. E.g., Borg (1991) provides an example of job satisfaction exploring how intra-individual variability in facet job satisfaction relates to facet importance. They find support both for the idea that more important facets are deemed more satisfying and for a u-shaped relationship where it is the most and least satisfied facets that are the most important. This variation depends on the domain being studied.

References

Blood, M.R. (1971). The validity of importance.. Journal of Applied
Psychology, 55, 487.
Borg, I. (1991). On the relationship between importance and satisfaction ratings on job aspects. Applied Psychology, 40, 81-92.
Rice, R.W., Gentile, D.A. & McFarlin, D.B. (1991). Facet importance and job satisfaction.. Journal of Applied Psychology, 76, 31.
Trauer, T. & Mackinnon, A. (2001). Why are we weighting? The role of importance ratings in quality of life measurement. Quality of life research, 10, 579-585.


Is there an analog to the five factor model for emotion?

The recently published Atlas of personality, emotion and behaviour is possibly what you are looking for(Mobbs, 2020).  Over 3,000 emotions are included in the analysis, a summary of which is below.  The article has a more comprehensive version.  The five factor model was derived through factorisation whereas the atlas was developed using a lexical/network approach.

References
Mobbs AED (2020) An atlas of personality, emotion and behaviour. PLOS ONE 15(1): e0227877. https://doi.org/10.1371/journal.pone.0227877
Declared Interest
I am the author of the atlas paper.


Why do hallucinations appear in depression?

Have a look at The God drug DMT. It causes people to see/talk to God and can be taken as an actual drug, but I believe it is also produced in the body during near death experiences. I am no expert in it but here's wikipedia: https://en.m.wikipedia.org/wiki/N,N-Dimethyltryptamine


Why can't people solve a riddle if you tell them irrelevant information?

I hope you still see this. I don't know a specific term for the exact kind of problem you mentioned. However, I would think that it can be explained by linguistic as well as cognitive or memory processes. Hence, my proposed explanation comes in two parts.

Linguistics

One view would be that it has to do with how we interpret language, specifically that we usually try to avoid irrelevant information. A classic in pragmatics (the field of linguistics that deals with how we actually use language to achieve things - make someone understand something, request things, or pose riddles) is the work by Paul Grice (1975).

Grice posited that we usually try to communicate cooperatively, i.e. in such a manner that it is easy for our communication partner to understand what we are saying. He said that we usually adhere to four conversational maxims: information (say as much but not more than is required for understanding the message), truth (say what you think is true), relation (be relevant), and manner (be clear and brief).

The important part is that, when trying to understand what someone has said, we also assume that the other is also following that rule. So when you say the cowboy thing, we usually assume that it's informative, relevant, and true and base all our interpretations and deliberations on that. This essentially means that to understand a statement you have to accept it as true. (Actually, Grice has fallen a bit out of favour with linguists, but newer accounts like relevance theory would lead to roughly the same conclusion.)

Memory

But that would not explain why that should still be the case after you tell the guesser that the information is actually irrelevant. This can likely be explained by the way memory works. A good start on this is the article by Lewandowsky and colleagues (2012). As soon as we get some information, we connect it to other information that is also currently relevant in our memory. That means that as soon as you say that the man is a cowboy, he is one in our memory. We connect the man (which was before just a non-descript man in a bar) with our mental concept of a cowboy. These connections get stronger the more they are used.

Your assertion that he actually wasn't a cowboy doesn't delete that connection, it likely only adds a "NOT" tag to it, but the connection itself is still there and has actually been strengthened further by the repeated mention. What is more, you do not provide an alternative (e.g., he's a truck driver or whatever) which could have lead to another, competing connection. To actually consider that "NOT" connection is effortful and strengthens the man--cowboy connection even further. Research usually calls this the misinformation effect or continued influence of misinformation.

Hope this helps! If someone with a better grip on pragmatics and/or memory processes is willing to correct (ha!) my explanation, I'd appreciate it.

References

Grice, H. P. (1975). Logic and conversation. In P. Cole & J. Morgan (Eds.), Syntax and semantics (Vol. 3). New York, NY: Academic Press.

Lewandowsky, S., Ecker, U. K. H., Seifert, C. M., Schwarz, N., & Cook, J. (2012) Misinformation and its correction: continued influence and successful debiasing. Psychological Science in the Public Interest (13). doi:10.1177/1529100612451018


Manipulating cognitive load in online experiments

Cognitive Load is very subjective, and typical mental interference tasks (like solving problems while working on another task) aren't used in studies involving Cognitive Load Theory (CLT), except to measure individual differences in Working Memory Capacity before the experiment begins. Most experiments in CLT ensure that all participants' CL is through the roof, to test whether any interventions have an effect on their CL and therefore performance. This is usually done through the complexity of the task itself, i.e. the difficulty of the subject matter specific to the subjects demographics and prior experience combined with a complex problem solving task (usually without mental interference).

So to answer your question, if you're more interested in Working Memory span or capacity, then this article outlines lots of different tasks you can give them. If you're more wanting to look at increasing CL from a CLT perspective, just look at any of the seminal studies by Sweller, Paas, Chandler, Ayers or Kalyuga for how they increased CL during the experiment.


I tried to do the math and got stuck. I asked for help at math.se and didn't get any further. My thinking is that it is not possible to write down a nice simple answer even though it is two equations and two unknowns, since system is not linear. When faced with math I cannot do, sometimes it is easier to just bring out the MATLAB hammer:

function [HR, FAR] = findHRFAR(c, acc)
    ACC = @(HR, FAR)(HR+1-FAR)./2;
    C = @(HR, FAR)(norminv(HR)+norminv(FAR))./2;

    HR = fminbnd(@(HR)temp(HR, c, acc), 0, 1);
    [SSE, FAR] = temp(HR, c, acc);

    [HR, FAR, C(HR, FAR), ACC(HR, FAR), SSE]

    function [SSE, FAR] = temp(HR, c, acc)
        [FAR, SSE] = fminbnd(@(FAR)((c-C(HR, FAR)).^2)+...
            ((acc-ACC(HR, FAR)).^2), 0, 1);
    end
end

It runs pretty fast, but ... the nested bounded optimization is ugly, and there may be a more efficient way to find the answer. I also don't see any reason this could not be done in Octave, Python, or any similar type program of your choice.


Comparing the Pomodoro Technique and flow state is like comparing tomatoes and oranges. They are not two different techniques that you choose between. Pomodoro is a productivity / time management technique, and flow is a mental state. They are related in the sense that you could use Pomodoro to help get into a flow state, but you could also use some other technique for that purpose, which it sounds like you already do.
The canonical reference for flow is Flow: The Psychology of Optimal Experience by Mihály Csíkszentmihályi, who first used the term to refer to a mental state.
One thing to keep in mind about flow is that it's good for productivity, but not necessarily good for self-improvement. In a flow state, you tend to accomplish tasks without conscious thought, which accounts for the high productivity. But this also means that you aren't thinking about how you might get better. The process of deliberate practice could be seen as an anti-flow technique, where you consciously focus on each step of a task in order to improve. (1)
I didn't find any rigorous scientific research about the effectiveness of the Pomodoro Technique. This HBR article has some informal results, and anecdotally it's a popular technique among knowledge workers.


What's the term in psychology for the way people think of concepts using examples?

You are talking about Exemplar Theory, since the question is almost verbatim from Wikipedia:

  For example, the model proposes that people create the “bird” category
  by maintaining in their memory a collection of all the birds they have
  experienced: sparrows, robins, ostriches, penguins, etc. If a new
  stimulus is similar enough to some of these stored bird examples, the
  person categorizes the stimulus in the “bird” category.

This contrasts with Prototype Theory, which proposes that categories are based on a single example rather than multiple:

  ... prototype theory would consider a category like bird as consisting of
  different elements which have unequal status - e.g. a robin is more
  prototypical of a bird than, say a penguin.

Other theories on categorization (or how a Concept is structured in the mind) include Essentialism, and Theory-theory.


Early foreign language experience and ease of learning foreign languages

This is an interesting question. Language development is a fascinating topic!

There are two types of language learning:
1. Learning a natural language (a language that is learned without any conscious effort)
https://en.wikipedia.org/wiki/Natural_language
2. Learning a second-language

Nearly all babies learn a natural language and some may learn more than one (they are what we call, bilingual babies).

There are some critical periods for learning any languages and these vary depending on the aspects of language one looks at (syntax, semantics, etc...). (https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3451048/)

Recent research shows that the approximate critical period for learning a second language appears to be at around 17 years old. (https://www.sciencedirect.com/science/article/pii/S0010027718300994) This does NOT mean that you will not be able to learn a second language after this, simply that it will be harder. Hence why it might have been easier for you to learn English at 8 years-old.

Now, depending on what languages you speak, it might be easier to learn some languages rather than others. For example, French and Spanish have very similar rhythms, phonemes, and are both romance languages, which would make it easier to learn one or the other, as long as you were fluent in one of them. However, it would be much harder for an English or French speaking person to learn Mandarin, because this tonal language is so different on many different aspects (for one, there are phonemes to which speakers of non-tonal languages are not sensitive, meaning that they cannot tell the difference between them). So yes, sometimes a language can be easy to learn, but at other times, it becomes much more complicated than having to learn a computer language.

As for being better at learning languages because you are bilingual, that is a possibility, but again, within the limits mentioned above of the language you decide to learn. Someone who knows French and Spanish may find it very easy to learn Italian, but still extremely hard to learn Cantonese. (https://www.psychologytoday.com/us/blog/life-bilingual/201506/can-second-language-help-you-learn-third)

Finally, psychologists do not agree on whether or not we have 'certain capabilities'. Many argue that anybody can become anything with the proper training and experience. Sure, as we grow, we become better in certain things, but you may find that by overcoming your preconceived ideas about yourself (ex: you are not good at learning computer languages), you can learn new things! I recommend reading Peak by Anders Ericsson. In his book, he really highlights how all the 'experts' were not born with special talents, but learned everything thanks to deliberate practice.


What term describes people that cannot feel pain?

Analgesia is the term used for inability to feel pain.
Hypoalgesia is the term for low sensitivity to pain.

Hereditary sensory neuropathy and Congenital insensitivity to pain are two known syndromes that contain these deficits as their symptoms.


What does it mean for there to be more variance within groups than between groups in IQ?

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)))


How often are complex networks and graph theory useful in computational neuroscience?

In my opinion as a computational neuroscience researcher, graph theory has not made major inroads into computational neuroscience because we don't have good evidence for what graphs characterise brains.

For example, my research revolves around how patterns of connections between neurons within local cortical circuits relate to information processing mechanisms performed by those circuits. But it's only very recently (e.g. Ko et al. 2011, Cossell et al. 2015, Markram et al. 2015, Lee et al. 2016) that we have detailed experimental data to build a connection graph on a very small scale.

The "small-world" concept was highly influential in neuroscience for a few years, but it turns out that "small-world" doesn't tell you anything much about the computations performed by a network, or even tell you anything much about it's detailed structure.

The work of Sporns (2004) and others have been applied to large-scale experimental data characterising connections between cortical areas. But again, the network motifs that come out from these experimental data sets statistically don't tell us much about what is going on computationally, or even how these areas connect to each other on a fine scale. The problem here is one of physical resolution of the techniques used.

Some aspects of random matrix theory apply to the sorts of networks that we can build, simulating what we know about connections within the brain (e.g. Rajan & Abbott 2006, Muir & Mrsic-Flogel 2015). Much of random matrix theory doesn't apply however, since graphs of realistic networks are non-Hermitian and can be quite constrained.


How can be explained from an evolutionary perspective the fact that some successful people do not want to have children?

Before addressing your true question, I just want to say that you can find individuals with almost any characteristic, even non-adaptive ones. Variation can exist for many reasons including genetic (e.g. mutations), or non-genetic reasons such as developmental problems or other environmental causes.

But back the true question:

  How can it be explained from an evolutionary perspective that some people have no desire to want children?

Evolutionary psychologists do not perceive the brain to be a conscious fitness calculating machine. To address such a question, it is fundamental to understand the difference between proximate and ultimate causation.

It is true that humans who didn't have any children would, by definition, be less reproductively successful in the past. Therefore, you would expect traits that lead to not having children be slowly selected out.

But you have to analyze this at the proximate level: What caused people in the past to have children? It was not mainly people thinking "I really want a child," rather it was people thinking "I desire sex with that person." What I am getting at here is that it was sex drive, rather than explicitly wanting children per se, that has been selected for.

It can often be helpful to compare us to other animals, especially animals who don't have as powerful cognitive faculties as us. Do you think that all other animals really think that "they want a child," or do you think that by some strange mechanism two individuals are attracted to each other to copulate (It might be scent, visuals, strength, or anything really)?

Of course, I have simplified things substantially. Probably there have been many psychological traits that have been helpful for reproduction other than simply sex drive. Probably also social bonding, and perhaps even the "desire for having children." However, my point here is that the desire to have children is not required, if another mechanism leads to people having children. However, it gets even more complex, because an infinitely strong sexual drive is not necessarily good, either. Being selective in who you mate with can be important as well for ultimate reproductive success.

Next question:

  How can we explain from an evolutionary perspective that some "successful" species, choose consciously to avoid parenthood at all?

There is a fundamental trade-off between how much effort and energy you invest in each offspring, and the number of offspring you have. If you have 10 children, you simply do not have as much time or resources to spend on each of them compared to if you had 2 children. This can lead to differences in how many of your offspring survive and eventually have their own offspring (Especially in conditions where resources are scarce). These differences in reproductive patterns were originally explored in r/K selection theory and now in Life history theory. Ignoring parenthood has its benefits in that it allows for more offspring and investing less energy into each.

Now you may ask the following:

  But what about after the child comes? For humans, if there is no one there to take care of the child, then it's guaranteed that the child will not survive.

It is clear that humans are a species where parenthood is important, because human infants are so helpless when born and for a long duration. Therefore, you would also expect it to have been selected for that people would invest time and resources in (i.e. to parent) the child when it shows up. You would probably expect this especially for women, because the child can survive without the father, but it is very difficult for it to survive without the mother (in the first few years, especially in ancient environments).

But, in fact, it is very rare that mothers have no desire to protect or care for their offspring after having it. So rare that it does not conflict with the evolutionary perspective. We also know that certain hormones are important for developing social bonds between the parent and offspring such as oxytocin.


In TD learning, is the weight function used as a linear filter?

They are the same in the two equations.  See equation 9.3:  v = w*u.  w and u are bolded in that equation to indicate that they are vectors.  In equation 9.3, they are vectors of simultaneously presented stimuli, but you can apply the same equation if u is a vector of a single stimulus over time and w are the weights of each time step of that stimulus.  Indeed, a linear filter is simply a way to weight different time steps of a time-varying input.  Note that v in equation 9.3 is a single value, whereas v in equation 9.6 is a function of t, i.e. it has a different value at each time point depending on what part of u is currently occurring.


Is it possible for certain people to perceive colors differently?

Yes, this scenario is possible, occurring with certain cases of brain lesions in specific areas of the visual cortex, the fusiform, lingual and posterior parahippocampal gyri.  These areas are analogous to what is referred to in primates as V4, or the 4th visual cortex, and are known to be involved (at least partly) in the perception of color (though see this commentary).

 Courtesy wikipedia

In this study, subjects with brain lesions were asked to identify colors in a blue ambient light (meant to mimic the outdoors) and under a reddish light (meant to mimic indoor lighting).

  ... the three patients...with abnormal matches on the blue, green and red chips made different matches than control subjects for pink, violet, turquoise and green targets... Their matches for these chips were shifted towards orange-red for the pink and violet
  targets and towards green for the turqoise target. One patient displayed a shift toward turquois[e] for the green target.

So, the level at which this "signal" is getting crossed can only be inferred from the level of the lesion, but presumably, the transduction of color by the cones and the processing of the colors in the P and K cells of the Lateral Geniculate is all still intact.

  Clarke, S., Walsh, V.,Schoppig, A.,Assal, G., Cowey, A. (1998) Colour constancy impairments in patients with lesions of the prestriate cortex. Exp Brain Res 123:154-158.


Can split-brain patients sleep like whales?

Short answer
An animal study did not reveal any effects on the synchronization of the cerebral hemispheres after callosotomy, as based on EEG recordings. When one hemisphere showed sleep patterns on the EEG, the other half would show similar activity.

Background
If intact commissures are needed between the two hemispheres to synchronize the two halves of the brain, a callosotomy would be expected to result in different EEG patterns during sleep. The most extreme case being laid out in the question, namely one hemisphere being in a different arousal state than the other.

In a study in split-brain cats (Susic & Kovaevic, 1974) the authors performed a callosotomy or related surgeries, including the sectioning of the anterior and posterior commissures*, and recorded the EEG during various behavioral states, including wake and sleep states and their transitions. After separation of the hemispheres the authors did not find any differences in EEG patterns across the two hemispheres in cats. Specifically, during transition from the alert to the drowsy state, the onset of EEG slowing appeared simultaneously in both hemispheres in all cats regardless of the type of section made. The shift from the synchronized to desynchronized pattern occurring during arousal or at the beginning of the paradoxal sleep (REM sleep) was always simultaneous in both cerebral hemispheres. The transition from REM to short arousal or to slow-wave sleep patterns was also bilaterally symmetrical. These results demonstrate that shifts in behavioral states from vigilance to sleep and vice versa are characterized by a simultaneous bilateral symmetry of the EEG events.

* List of surgical groups (n= 14 per group)

Cats with sections of commissural systems between hemispheres and diencephalon (corpus callosum, fornix, commissura hippocampi,
septum, commissura anterior, massa intermedia of thalami, commissura posterior, commissura habenularum, commissura intercollicularis).
Cats with interrupted left optic tract and sections of the commissural system between hemispheres and diencephalon.
Cats with an interrupted left optic tract and section of the left half of the midbrain tegmentum (the lesion passed intercollicularly in the
dorsal part, and ventrally into the premesencephalic area).
Cats with an interrupted left optic tract section of the left half of the midbrain tegmentum and section of commissural systems, combined with the section of crossed fibers of the commissura supraoptica.

Reference
- Susic & Kovaevic, Brain Res (1974); 65: 427-41


Can stress be sustained without reflective thought processes

In your example, you are describing social stress. I think you are right that social stress is mainly driven by reflective processes. Also, social stress without reflective processes sounds quite implausible to me.

However, we should keep in mind that stress can come from various sources, some of which are non-social. For example, one common way to induce stress in psychological experiments is to use a physiological (as opposed to a psychosocial) stressor. In the classic cold pressor test, participants are instructed to put their hand into ice water. This starts a stress reaction, as measureable for example by increases in cortisol. I think it's pretty safe to say that reflective processes are not the driving factor here.

For a review on different methods to induce stress in the lab, see for example:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3181831/


Is implicit and explicit memory a useful distinction?

No, the distinction is real, not arbitrary. Implicit and explicit memory show different hallmark behavioral characteristics. A good overview of the difference between explicit and implicit memory is available in the MIT Encyclopedia of the Cognitive Sciences. The wikipedia page on implicit memory also has some useful information.
Perhaps the most important piece of evidence we have for this distinction is not behavioral, but from a double dissociation in neuropsychology: some brain damaged patients have impaired implicit memory but intact explicit memory, whereas others have impaired explicit memory but intact implicit memory (e.g. Gabrieli et al, 1995). This is possible because implicit and explicit memory are thought to have separate neural substrates (e.g. Squire, 1992).
There are a lot of questions in your second paragraph and I'm not quite sure I follow. But to be clear, implicit/explicit memory is not the only distinction one can make on memory systems. It is one of many.

Gabrieli, J. D., Fleischman, D. A., Keane, M. M., Reminger, S. L., & Morrell, F. (1995). Double dissociation between memory systems underlying explicit and implicit memory in the human brain. Psychological Science, 6(2), 76-82.
Squire, L. R. (1992). Memory and the hippocampus: a synthesis from findings with rats, monkeys, and humans. Psychological review, 99(2), 195.
Chicago


Does intoxication ever improve reaction time?

In short: none that I could find. Indeed, it's a very one-way relationship - the more you drink the worse reaction time gets. However, there is a starting point, which is generally put around .02-.06 depending on your chosen study - below that threshold the effect of BAL on reaction times is difficult to pin down. Most studies I found showed that below .05% often showed no change in cognitive functioning regarding reaction times, though it was often theorized that intoxicated people are able to compensate for their impairment under normal testing conditions, as in this study: Alcohol increases reaction time and errors during decision making

This suggests a possible answer, however - you knew if intoxicated your reaction times could be worsened, so you focused extra resources on maximizing them.

Also, studies in general are statistical in nature - none say that "no one ever showed improved reaction time while intoxicated", because sometimes its just a fluke, sometimes people are especially trained at compensating for intoxication (even at a subconscious level), and a host of other similar factors.

What this all indicates is that even if your reactions were repeatedly tested under measured circumstances, you might very well be able to show improved reaction times under varying level of intoxication; however this is extremely likely to require more of your mental resources, so that under stress or complicated situations you would find real-world performance to be poorer.

Finally, I would also warn that reaction time does not necessarily correlate with any/all other cognitive tasks. Those with even .05 BAL are often found be twice as likely to be in an automotive accident, even though most reaction time studies and general cognitive ability tests would show low/no impairment.

But, still I cannot say there is any literature I can find that studies specifically the effect of low-moderate levels of intoxication on a variety of individuals, especially with the goal of identifying potential enhancement of any cohort within the study. At least if there was such a study it could have been considered to have failed to find any result worthy of publishing, or be rephrased to be a study that showed reduce reaction time in fitting with other similar research.


That paper is kinda old and as you point out it is paywalled. Try this free paper instead.
A brief form of the affective neuroscience personality scales.

The Affective Neuroscience Personality Scales (ANPS) were developed to measure behavioral traits related to 6 affective neurobiological systems (play, seek, care, fear, anger, and sadness). However, the ANPS has a number of problems, including an ill-defined factor structure, overly long scales, and items that are poorly worded, ambiguous, and of questionable content validity. To address these issues, we constructed an improved short form of the ANPS--the Brief ANPS (BANPS). Three studies demonstrated that the 33-item BANPS has a clear and coherent factor structure, relatively high reliabilities (for short scales), and theoretically meaningful correlations with a wide range of external criteria, supporting its convergent and discriminant validity. Unlike typical short-form scales, the BANPS improves upon the psychometric properties of the long form, and we recommend its use in all research contexts.

This is the only other paper I have the ability to cite about ANPS:
The brain's emotional foundations of human personality and the Affective Neuroscience Personality Scales

The anatomical, neurochemical, and functional homologies of subcortical emotional networks strongly indicate underlying evolutionary continuities in affective principles in all mammalian brains (Panksepp and Biven, 2011). Since it is widely believed that individual's emotional inclinations (temperaments) are foundational for human personality development, the goal of the following work was to try to ground personality assessment on the affective circuits that all mammals share. But before we summarize work with the Affective Neuroscience Personality Scales (ANPS), we briefly note historical antecedents of this way of thinking about human personality.
We sustained the capitalization convention in our attempt (i.e., the ANPS) to translate anoetic (without knowledge) emotional experiences to noetic (knowledge linked) and autonoetic (thought linked), language-based evaluations of the potential influences of primal affects in the personality structures of human minds. However, rather than RAGE and PANIC/GRIEF, we decided to use the terms ANGER and SADNESS in this paper and in our construction of the Affective Neuroscience Personality Scales (ANPS), since those are labels that are generally more understandable for most individuals. Still, the theoretical implication is that these systems are critically important for the various feelings highlighted by these scientific terms – e.g., the ANGER system energizes states commonly labeled as ‘irritability’ and ‘anger’.
There are several principles basic to understanding these seven brain systems: (1) These emotion systems are subcortical networks and lower brain regions have evolutionary primacy in generating these basic emotions and their affects, while learning and higher brain functions can be deemed to be secondary and tertiary processes. (2) To the best of our knowledge, these emotion systems, situated in ancient brain regions, are largely homologous in all mammals. (3) These basic emotions also have similar chemistries in all mammals. (4) These brain systems generate instinctual behavioral responses that are closely linked to the raw, primal affects that accompany those responses. (5) The integrity of these seven systems is demonstrated by the ability to elicit coherent specific emotional responses and/or the associated affects with localized brain stimulation – as evaluated by the capacity of the subcortical arousals to mediate ‘reward’ and ‘punishment’ functions that control learning. (6) Lastly, these systems remain relatively unscathed in animals whose neocortices were surgically removed in early development (see Panksepp, 1998).
In summary, emotional responses from each of the primary process emotions can be activated by localized subcortical ESB or chemical brain stimulation. That decortication of young animals generally leaves the expression of these emotions intact (Deyo et al., 1990 and Panksepp et al., 1994), further reinforces the subcortical nature of these emotion systems. Also, each instinctual emotional system engenders affective valence since animals terminate the stimulation of ANGER, FEAR, and SADNESS, while actively working to obtain SEEKING, LUST, CARE, and PLAY system arousals (Panksepp, 2005). However, there are reasons to believe the SEEKING system is foundational for aspects of all of the other primal emotions (e.g., during FEAR intensification, the shift from freezing to flight may be due to recruitment of SEEKING related dopaminergic psychomotor drive).
Based on our first study using these scales, reliabilities for the ANPS scales, computed as Cronbach's alpha, were reported ranging from .65 to .86 with the PLAY and SEEK scales below .70 and the FEAR, ANGER, and Spirituality scales above .80 (Davis et al., 2003). Multiple data sets using the revised ANPS 2.4, have shown all reliabilities now over .70 (unpublished data).
Contrasting self-rating data for ANPS and FFM scales, as seen in Table 1, revealed that each of the ANPS scales except Spirituality correlated strongly with at least one of the FFM scales as follows: (1) SEEK with Openness to Experience (r = .47), (2) PLAY with Extraversion (r = .46), (3) CARE with Agreeableness (r = .50), (4) FEAR with Emotional Stability (r = −.75), (5) SADNESS with Emotional Stability (r = −.68), and (6) ANGER with Emotional Stability (r = −.65) as well as with Agreeableness (r = −.48) (Davis et al., 2003). The data supported strong relationships between primary emotions and the most widely accepted model of human personality, which was consistent with the hypothesis that these six brain emotion systems form a foundation for the adult five-factor personality model.