Does mental satisfaction lead to physical satisfaction?

The Canadian Mental Health Association of Ontario is pretty unambiguous about the bidirectionally causal relationships between physical and mental well-being:

  Mental and physical health is fundamentally linked. There are multiple associations between mental health and chronic physical conditions that significantly impact people’s quality of life, demands on health care and other publicly funded services, and generate consequences to society.  The World Health Organization (WHO) defines: health as a state of complete physical, mental and social well-being and not merely the absence of disease or infirmity.   The WHO states that “there is no health without mental health.”

  Nowhere is the relationship between mental and physical health more evident than in the area of chronic conditions. The associations between mental and physical health are:

  Poor mental health is a risk factor for chronic physical conditions.
  People with serious mental health conditions are at high risk of experiencing chronic physical conditions.
  People with chronic physical conditions are at risk of developing poor mental health.

  The social determinants of health impact both chronic physical conditions and mental health. Key aspects of prevention include increasing physical activity, access to nutritious foods, ensuring adequate income and fostering social inclusion and social support. This creates opportunities to enhance protective factors and reduce risk factors related to aspects of mental and physical health.

The Mental Health Foundation's report, "Let's get physical: The impact of physical activity on wellbeing" offers a good review of several connections between exercise and well-being of both kinds. It's very broad, yet accessible, so I'll let it speak for itself. A peer-reviewed research literature review on the same topic is also available (Penedo & Dahn, 2005), as well as some original correlational research that linked physical and psychological health subjectively (Edwards, Ngcobo, Edwards, & Palavar, 2005). These are just some quick results from a Google search for "physical mental well-being correlation"; plenty more out there.

References

- Edwards, S. D., Ngcobo, H. S., Edwards, D. J., & Palavar, K. (2005). Exploring the relationship between physical activity, psychological well-being and physical self-perception in different exercise groups. South African Journal for Research in Sport, Physical Education and Recreation, 27(1), 75–90. Retrieved from http://www.sirc.ca/newsletters/mid-jan10/documents/S-996370.pdf.
- Penedo, F. J., & Dahn, J. R. (2005). Exercise and well-being: A review of mental and physical health benefits associated with physical activity. Current Opinion in Psychiatry, 18(2), 189–193.


What are the limits of language with respect to communicating the actual reasons that go in making a decision?

Perhaps oxytocin can be associated with Sinek's why. I think this article can be helpful:
Oxytocin and the Biopsychology of Performance in Team Sports

From the discussion:

  The ability to perceive and understand the mental state of others is very important for an athlete in a sport and especially so in a team setting where working together toward common goals is key. Athletes have to infer internal states in order to make sense of or predict a teammate or opponent’s behavior.

Simon Sinek describes the process of finding a common thread in all your actions. He calls this "your why". Sinek states that the why is an unconscious part of your mind. The why is discovered by searching for patterns in situations where you feel motivated. A slogan-like phrase should then be developed in order to represent the why. The purpose of the phrase is to enable you to be conscious about the motivational drive. You should use the phrase as a guide in order to make your life more meaningful. Even though Sinek talks a lot about "finding your why", then he doesn't talk much about techniques of applying it. I think that the why-phrase can be used in a couple of ways:

As a guideline in making new decisions.
As a tool for unconscious focusing through priming. This is the main function of slogans: The Psychology of a Smart Slogan
As a starting point for building an identity, that reminds you about your why. An example of this is the military, where a motto is the equivalent of a "why-phrase". The uniforms and the etiquette also represent the unconscious why.


Which psychological word describes this situation best?

Maybe you mean an engagement?
If though, a positive psychology have term flow state - when you fully immersed. Here is wiki article about it. Or hyperfocus - article.

Components of flow state:

Intense and focused concentration on the present moment

Merging of action and awareness

A loss of reflective self-consciousness

A sense of personal control or agency over the situation or activity

A distortion of temporal experience, one's subjective experience of time is altered

Experience of the activity as intrinsically rewarding, also referred to as autotelicexperience


How to compare IAT (Implicit Association Test) results of two different groups?

I assume IAT gives you a score for each person.

I imagine you could just do an independent groups t-test to assess whether the means of the two groups significantly differ.


Avoiding Cognitive dissonance,is it a necessity?

I think you're confusing science with politics.  The APA and other such professional organizations have not, to my knowledge, concluded that cognitive dissonance should be avoided or even minimized.  I'm unaware of any evidence that suggests that cognitive dissonance directly causes distress or suffering.

The position of psychology, as a science, is that cognitive dissonance is a phenomenon that exists and has certain properties.  There is no normative stance from the field as a whole.

What happens in these cases is that political groups engage in activism and argue that such things should be minimized; the same is true of stereotyping, for instance.  You may agree with the dominant political opinion, but it's not a scientific question, per se.


What terms describe "schema" at various stages of acceptance?

I don't know of separate terms to differentiate 'schema present in an individual' from
'potential "schemata/patterns/ideas" out in the world not yet encountered by the individual', but with regard to 'schema currently being added or adjusted by an individual', I can at least offer some related terms.

Accommodation is the process by which schemata are adjusted most generally.
With respect to identity status, which might be considered self-schemata, one's status is classified as in moratorium during periods of active adjustment. I find James Marcia's theory useful often, because it differentiates individuals in terms of two factors:

Whether they have a sense of personal identity
Whether they have attempted to scrutinize and develop their personal identities

I'm only wary of dichotomizing these factors, which might be better understood as dimensions (I doubt whether anyone is truly at an absolute zero)...but that's slightly tangential, as it's somewhat easier to imagine schemata being completely stable or absent in a meaningfully dichotomous sense.


Yes, there is a term for this phenomenon. It is called stopped-clock illusion. It’s a type of chronostasis or a kind of temporal illusion, that the time interval is perceived to be longer than it really is.

Though I’m not totally convinced myself, the current explanation is like this:

This phenomenon happens because the brain fills in the perception gap that occurs (while changing visual targets) with the end visual target. This is because, when we change visual targets by moving our eyes, the overall visual scene will become blurred during that time and the brain avoids this confusing visual input by suppressing it, which results in a perception gap during that period of time. When the gaze changing ends, the brain fills this gap with the static image of the end visual target instead. As a result, the end visual target will be perceived to exist longer than it is actually seen. This suppressing of the blurred image also explains why we never experience blurry images while we move our eyes to see things around us.

References:

Wikipedia. Chronostasis
BBC Future. The mystery of the stopped clock illusion

More in-depth, academic references:

Eagleman DM. Human time perception and its illusions. Curr Opin Neurobiol. 2008 April;18(2):131–136.
van Wassenhove V, Wittmann M, Craig AD, Paulus MP. Psychological and neural mechanisms of subjective time dilation. Front Neurosci.2011;5:56.


What delay between two audio sources is seen as "noticeable" to most people?

It greatly depends on what you mean as 'noticeable' - what/why do you want to synchronise, and how it reaches the ears from physical speakers.

Keep in mind that a sound source being 30cm/1 feet further from the ear is about the same effect as a millisecond of delay (speed of sound ~340m/s) - thus, synchronising on the order of microseconds is generally unneccessary unless you somehow have and need sub-millimeter localisation accuracy. That being said, small delays can cause phase cancellation issues which would be noticeable, but would depend on exact placement of sound sources.

However, if we're talking about the limits of the mind - there are two well known phenomena; first is the limit where mind perceives sound as simultaneous with visual stimulus (despite them really being slightly offset), and the second is where mind perceives two close-but-separate sound spikes as a single event (with the loudest masking the weaker). I can't find the exact limits now, but both of them should be somewhere between 1 millisecond and 5 milliseconds if I recall correctly.


Pleasure can be implicated in a chemical reaction in the brain, but does this really affect the intensity of the feeling?

Short answer
In case of dopamine, its amounts present in the reward pathway in the brain correlates positively with the intensity of pleasure experienced.

Background
To focus the answer I'll narrow the scope of this post to one of the most extensively investigated emotional centers in the brain, namely the reward center involving the dopaminergic mesolimbic pathway.

Dopamine (DA) release in this system rewards the brain's host for beneficial things essential to life, such as eating, drinking and having sex.

It is also one of the major neural centers in the brain involved in addiction, including nicotine, cocaine and methampetamine addiction, as well as gambling and pathological risk-taking behaviors.

The opiate class of narcotics, most notably cocaine, amphetamine, methamphetamine, morphine, heroine and their analogues invoke a massive increase in DA levels in the mesolimbic pathway. An increase in DA levels has been shown to be a final (secondary) common pathway that mediates the rewarding properties of these drugs of abuse, explaining their addictive properties (Chiara & Imperato, 1988).

In humans it has been established by behavioral experiments that the magnitude of ventral striatal DA release (the striatum is a part of the reward system in the brain) correlates positively with the hedonic (pleasure) response associated with amphetamine (Drevets et al., 2011). In other words, more DA is correlated with more happiness and thus the amount of DA indeed correlates with the intensity of the feeling associated with its release in the reward system.

As a side note on this; a notorious problem with many drugs of abuse are their purity. For example, Coca leaves cause a mild stimulant high when chewed. As far as I know, the American Indians have not suffered from overt physical or psychological dependence on these leaves in the thousands of years they probably have used them. However, shortly after the discovery of coca leaves (and opium poppies for that matter) by the Old World, the active ingredient was purified and eventually isolated. Cocaine (and morphine) cause a sudden and massive increase in dopamine levels (Romach et al., 1999), in turn not just leading to feelings of pleasure, but to near-instantaneous, full-blown ecstatic euphoria. It is this notorious 'first-time high' that virtually every addict keeps on pursuing, and which they will unfortunately never experience again in their life due to tolerance that build up almost instantly after first use of highly purified preparations of coca (crack, cocaine) and poppies (morphine, heroine).

Post scriptum
In general, the 'biochemistry' of the brain refers to neurotransmitters. Their actions are primarily due the binding of these compounds to their respective receptors. The process of neurotransmitter release and receptor binding are not chemical reactions in the strictest sense of their meaning, as stated in your question. The secondary responses of the postsynaptic neuron may, or may not involve chemical reactions. Some second messenger systems do rely on chemical reactions (the metabotropic receptors including the dopamine receptors) while others do not (ion channel-coupled receptor systems for example).

References
- Chiara & Imperato, PNAS (1998); 85: 5274-8
- Drevets et al., Psychiatry (2001); 49: 81–96
- Romach et al., Arch Gen Psychiatry (1999); 56(12): 1101-6


Do major historic events have a lasting impact on humankind's objective happiness?

Depends what you mean by "objective happiness". If we use the term in the way that it's used by Kahneman etc., meaning that

  In the special conditions of the clinic or laboratory it is sometimes possible to
  obtain continuous or almost continuous reports of experienced utility from patients or
  experimental subjects. Continuous measures are of course impractical for the
  measurement of objective happiness over a period of time. Sampling techniques must be
  used to obtain a set of values of moment-utility that adequately represents the intended
  population of individuals, times and occasions. For example, a study of the objective
  happiness of Californians should use a sample of observations that reflects the relative
  amounts of time spent on the freeway and in hot tubs. Techniques for sampling times
  and occasions have been developed in the context of Experience Sampling Methodology
  (ESM) (Csikszentmihalyi, 1990; Stone, Shiffman and DeVries, 1999).

It's hard to imagine getting such data retrospectively from ancient or even just past populations.

Ref quoted: Kahneman, D. (2000). Experienced utility and objective happiness: A moment-based approach. In D. Kahneman & A. Tversky (Eds.), Choices, values and frames (pp. 673-692). New York: Cambridge. University Press and the Russell Sage Foundation.

Generally, diet and/or physical trauma leave a bone recod for archeologists to study. Alas I'm not aware of neurochemistry of past populations being ammenable to study (other than comparative studies across current species, e.g. humans vs apes).


If a human brain would be placed inside that of an animal: Could it talk?

Part of what makes speech possible is a complex set of interactions between a number of different muscles that control aspects of producing speech sounds like airflow and mouth shape. Humans are unique in the complexity of the sounds that we can produce. Even if we granted the science-fiction that would be necessary to put a human brain into a chimpanzee and somehow managed to reconnect the analogous neural pathways to sensory organs and effectors, human speech wouldn't be possible because it requires a human body.

This Wikipedia page gives an overview of the biological developments that support speech.


At the moment, there are no TMS/tDCS protocols that were approved for the home use in USA or EU. So, please, don´t. Fortunately, TMS devices are quite expensive and cannot be used by a single man. tDCS is easier, but decent companies on the market like NeuroConn or Neuroelectrics will not sell an equipment to a private person.
Foc.us device, by the way, was proved to impair the memory [1].

1.Steenbergen, Laura, et al. "“Unfocus” on foc. us: commercial tDCS headset impairs working memory." Experimental brain research (2015): 1-7.


How to measure employee ownership, team spirit, and collaborative nature?

It sounds like you are talking about a range of concepts.
You could look into measures related to:

Organisational citizenship behaviour: This tends to look at good discretionary behaviors such as collaboration, helping out colleagues, and so on.
Engagement and affective commitment: Both these constructs are closely related to motivation and alignment with the organisation (e.g., ownership).

Just do a search on google scholar for articles on these topics and look at the methods sections.

There are a range of popular measures that could readily be applied as self-report instruments. Alternatively, you could get peers or supervisors to rate employees.

A few suggestions:

Lee and Allen's (2002) Organizational Citizenship Behavior Scale.
Utrecht engagement scale


What are the advantages of 2AFC in a psychophysical discrimination task?

What makes a task a two alternative forced choice task?

I am beginning my answer with this question because there is a general misconception about what 2AFC really means. Many people believe that 2AFC refers to any task where subjects are asked to select one of two options (yes/no, old/new, bright/dim). However what defines it instead is that there are two stimuli presented on each trial.

Your definition can be thought of as an example of a interval-2AFC (AKA temporal-2AFC), but your example is not a typical 2AFC paradigm. It is true that both s1 and s2 are presented prior to the decision, however, typically (in my experience) subjects only respond about one of the stimuli (like my examples in the figure above). That said, the important distinction is that in a true 2AFC task, subjects are presented with two stimuli per trial. Whenever subjects are judging a single stimulus per trial it is considered a discrimination task or a detection task (e.g., judging the direction of motion in a random dot kinematogram).

Pros and Cons of Detection and 2AFC Tasks

The most cited reason for using the 2AFC procedure is that it is unbiased. For example, in my gender discrimination task (presented in the leftmost panel of the figure), a participant could be biased to respond male more so than female. But in the 2AFC version of the task, the participant is choosing a spatial location (left/right) or an interval (1st or 2nd), so any bias they have about gender is eliminated from the decision. If bias is reduced or eliminated it has the added benefit of rendering assumptions necessary for signal detection models obsolete (e.g., that underlying distributions are gaussian).

A second reason for using 2AFC is that there is a performance enhancement resulting from the fact that participants are provided with more information on each trial. That is, in one case you are presented with a single face and must decide which distribution it comes from, which is harder than being presented with one face from each distribution and having to judge which face belongs to the target distribution.

As for the cons, the aforementioned pros may not be true at all. For that discussion I point you to this 2008 paper by Yeshurun, Carrasco, & Maloney.

Ultimately the better procedure will depend on what your question is and what assumptions you are or are not willing to make.


Are there advantages of psychopathic traits?

While the term Psychopath is often employed in common usage along with "crazy", "insane", and "mentally ill", according to criminal psychologist, Robert Hare, there is a distinction between those with psychosis and psychopathy (Hare, 1999).

Something to bear in mind though, is that no psychiatric or psychological organisation has sanctioned a diagnosis titled "psychopathy" (WikiPedia, n.d.), yet assessments of psychopathic characteristics are widely used in criminal justice settings in some nations and may have important consequences for individuals. In psychology and psychiatry, the Diagnostic and Statistical Manual of Mental Disorders (DSM) written by the American Psychological Association (APA) and International Classification of Diseases (ICD) written by the World Health Organisation (WHO) introduced the alternative and more accepted diagnoses of antisocial personality disorder (ASPD) (APA, 2013 p.659) and dissocial personality disorder (DPD) (WHO, 2010) which is also covered in ICD-11 under 6D10 Personality disorder (WHO, 2018).

  Antisocial personality disorder is a pattern of disregard for, and violation of, the rights of others (APA, 2013 p.645).

Picking apart the Guardian's review (Adams, 2012) mentioned in the question talking about the book The Wisdom of Psychopaths (Dutton, 2013; Wisdom of Psychopaths, n.d.) the idea that they would be the only ones who can have an

  emotionally detached mind in bomb disposal

would brand all bomb disposal teams as psychopathic. The same could be said for doctors, nurses and paramedics dealing with medical emergencies, yet they "detatch" through the use of compartmentalisation.

  Compartmentalization is a subconscious psychological defense mechanism used to avoid cognitive dissonance, or the mental discomfort and anxiety caused by a person's having conflicting values, cognitions, emotions, beliefs, etc. within themselves.

  Compartmentalization allows these conflicting ideas to co-exist by inhibiting direct or explicit acknowledgement and interaction between separate compartmentalized self states (Leary & Tangney, 2011).

Carolin Showers (1992) described compartmentalisation as

  the tendency to organize positive and negative knowledge about the self into separate, uniformly valenced categories (self-aspects). As long as positive self-aspects are activated, access to negative information should be minimized.

Similarly the

  psychopath's ability to intuit anxiety as demonstrated by, for example, customs officials

could also brand doctors and therapists as psychopathic.

Whilst questions like this opens up a good debate on psychopathy, I also believe that just like the above, the idea of psychopaths in business hierarchy is open to opinion.  I have also heard of the idea that there are narcissists in high ranking positions within organisations (Live Science, 2008).

These opinions form interesting debates as psychopathy may become accepted in more branches of psychology other than criminal psychology. It may also shape the criminal psychology viewpoint.

References

APA (2013). Diagnostic and Statistical Manual of Mental Disorders: 5th Edition (DSM–5) Washington, DC: American Psychiatric Publishing

Dutton, K. The Wisdom of Psychopaths. London: Arrow Books.

Hare, R. D. (1999). Without Conscience: The Disturbing World of the Psychopaths Among Us. New York: Guilford Press. p. 22.

Leary, M. R., & Tangney, J. P. (Eds.). (2011). Handbook of self and identity. Guilford Press.

Live Science (2008). Narcissists Tend to Become Leaders. [Online]Retrieved from: https://www.livescience.com/5128-narcissists-tend-leaders.html

Showers, C. (1992). Compartmentalization of positive and negative self-knowledge: Keeping bad apples out of the bunch. Journal of Personality and Social Psychology, 62(6), 1036-1049.DOI: 10.1037/0022-3514.62.6.1036

WHO (2010). International Statistical Classification of Diseases and Related Health Problems 10th Revision (ICD-10): 2010 Version [Online]Retrieved from: http://apps.who.int/classifications/icd10/browse/2010/en#/I

WHO (2018). **International Statistical Classification of Diseases and Related Health Problems 11th Revision (ICD-11)* [Online]Retrieved from: https://icd.who.int/browse11/l-m/en#/http%3a%2f%2fid.who.int%2ficd%2fentity%2f941859884

WikiPedia (n.d.). Psychopathy. [Online]Retrieved from: https://en.wikipedia.org/wiki/Psychopathy

Wisdom of Psychopaths (n.d.). Are you a Psycopath? [Online]Retrieved from: http://wisdomofpsychopaths.com


Is there a case of multiple personalities that is not a disorder?

Well, this is mostly a technicality (but then so is the DSM definition of any mental disorder). The DSM allows for a DDNOS; actually in DSM-5 that would be OSDD "Other Specified Dissociative Disorder" diagnosis:

  This category applies to presentations in which symptoms characteristic of a dissociative
  disorder that cause clinically significant distress or impairment in social, occupational, or
  other important areas of functioning predominate but do not meet the full criteria for any of
  the disorders in the dissociative disorders diagnostic class. The other specified dissociative
  disorder category is used in situations in which the clinician chooses to communicate
  the specific reason that the presentation does not meet the criteria for any specific dissociative
  disorder. This is done by recording “other specified dissociative disorder” followed
  by the specific reason (e.g., “dissociative trance”).
  Examples of presentations that can be specified using the “other specified” designation
  include the following:

  Chronic and recurrent syndromes of mixed dissociative symptoms: This category
  includes identity disturbance associated with less-than-marked discontinuities in
  sense of self and agency, or alterations of identity or episodes of possession in an individual
  who reports no dissociative amnesia.

  [more types follow but are not relevant here]

So OSDD type 1 would include any cases of multiple personalities/identities without dissociative amnesia, so in this (DSM) sense you can't have your cake and eat it, i.e. multiple personalities/identities would always be a disorder, albeit with not-so-obvious name, assuming the extent of these personalities/identities is sufficient to be deemed clinically relevant (by the diagnostician). For reference, the brief DID definition (without all the usual caveats of the full def such as not being caused by drugs or other medical conditions, but being clinically relevant in terms of distress/impairment etc.) is

  Dissociative identity disorder is characterized by a) the presence of two or more distinct personality states or an experience of possession and b) recurrent episodes of amnesia.

So clearly if (b) is dropped from DID resulting in OSDD type 1, we're left with what you're asking for (again as long as it's clinically relevant distress/impairment, not caused by drugs or other medical issues etc. These are common verbiage caveats added to most definitions of disordes in the DSM.) So then this is pretty much an issue what is clinically relevant distress/impairment so that a cluster of symptoims is a disorder. There is only one additional, unusual caveat added to DID in DSM-5 (and this would apply to OSDD as well):

  Note: In children, the symptoms are not better explained by imaginary playmates or other fantasy play.

On the topic of prevalence and presentation, a 2014 review notes

  Chronic complex DD [dissociative disorders] include dissociative identity disorder (DID) and the most common form of dissociative disorder not otherwise specified (DDNOS, type 1), now known as Other Specified Dissociative Disorders (OSDD, type 1).

  [...]

  The most common type of DDNOS, which has been replaced in the Diagnostic and Statistical Manual of Mental Disorders-5, called other specified dissociative disorder (OSDD), is typically found to be the most prevalent DD in general population and clinical studies with a prevalence rates up to 8.3% in the community reviewed in [...]. Across general population studies, the most severe DD, dissociative identity disorder (DID) has a prevalence of approximately 1% and has been found in .4 – 14% of psychiatric inpatients and outpatients, depending on the sample [...]. Most DDNOS/OSDD patients are similar in presenting symptoms, history, clinical course, and treatment response to DID patients, so DDNOS/OSDD is combined with DID here [...].

  Many clinicians and lay people believe that DID presents with dramatic, florid personality states with obvious state transitions (switching). These florid presentations are likely based on media stereotypes, but actually occur in only about 5% of DID patients [...]. The vast majority of DID patients have subtle presentations characterized by a mixture of dissociative and PTSD symptoms embedded with other symptoms such as posttraumatic depression, substance abuse, somatoform symptoms, eating disorders, personality disorders, and self-destructive and impulsive behaviors [...]. A classic presentation includes a history of multiple treatment providers, numerous serious suicide attempts resulting in repeated hospitalizations, and good medication trials typically with limited or no benefit [...].

  Although the media and public are often overly fascinated with DID dissociated self-states, the complex symptomatic presentation of DID receives more clinical attention from trained clinicians [...]. Under-recognition of DID is common because the most obvious and pressing aspect of a patient’s clinical presentation may be one of the many comorbid disorders (e.g., severe mood disorders, posttraumatic stress disorder [PTSD], eating disorder, substance abuse, BPD), or the pseudopsychotic symptoms related to the overlap and intrusions of self-states into consciousness. This overlapping influence of self-states causes “passive influence” phenomena or Schneiderian first rank symptoms, which are more common in DID than overt, obvious “switching” of states. DID patients experience more first rank symptoms than do individuals with schizophrenia, with the exception of thought broadcasting or audible thoughts [...]. Intrusions into consciousness may be partially excluded from consciousness (e.g., hearing voices of states, thought insertion/withdrawal, “made” actions/impulses) or fully excluded from consciousness (e.g., time loss, fugues, disremembered behaviors; [...].

So yeah, weirdly, the otherwise specified DDs are much more common than the "flagship" DID... and (thus) the transitions between personalities/identities are mostly non-abrupt.

And finally whether DDs can occur without trauma, the DSM-5 says yes, but also acknowledges that DDs commonly occur after trauma:

  The dissociative disorders are frequently found in the aftermath of trauma, and many
  of the symptoms, including embarrassment and confusion about the symptoms or a desire
  to hide them, are influenced by the proximity to trauma. In DSM-5, the dissociative disorders
  are placed next to, but are not part of, the trauma- and stressor-related disorders, reflecting
  the close relationship between these diagnostic classes.

And going back to the review for some empirical quantification:

  Epidemiological studies have found that mood, somatoform, anxiety disorders, and substance abuse are commonly associated with antecedent trauma, as well as PTSD [...]. These disorders are also common co-morbidities of patients with chronic complex DD [...]. For example, in a prospective treatment study of DID and dissociative disorder not otherwise specified (DDNOS) patients, 89% also had PTSD (n = 242), 83% had a mood disorder (n = 226), 50% had an anxiety disorder other than PTSD (n = 136), 30% had an eating disorder (n = 81), 22% had a substance abuse/dependence disorder (n = 61), and 22% had a somatoform disorder (n = 59).

But you have to keep in mind that a study like the last one is restricted to subjects who are seeking treatment, so they experience one or more distressing symptoms.

On the other hand, I'm guessing your question might have been motivated by a Vice article that has a similar title to your question, but which is mainly talking about the "multiplicity community" whose members are appanretly not distessed by their experiences. Likewise there's a "Plural Activism" movement, the mission statement of which is apparently

  Plural Activism will bring public awareness to
  the fact that multiples, no matter their origin,
  are able to live healthy, successful lives
  without integration.

So that goes back to what I was saying about psychiatrists (and their studies) mostly seeing people who are distressed. Quoting from Vice:

  The multiplicity community insists on being seen as healthy—even normal. This is our reality, they argue. Why are you imposing your reality onto us? Dissociative Identity Disorder (DID)—and its controversial precursor, Multiple Personality Disorder—are terms roundly rejected by the community, and most of them don't feel that they belong in the Diagnostic and Statistical Manual (DSM) at all. It's not that they don't believe people can suffer from DID (or, more broadly, Dissociative Disorder Not Otherwise Specified [DDNOS]). They just don't accept that they suffer from it. To them, all those with DID/DDNOS are multiple, but not all multiples are DID/DDNOS. Contrary to what a DID/DDNOS diagnosis implies, multiples want everyone in their system to be seen as people. Not fragments, alters, or personalities, but distinct individuals who happen to be inhabiting the same physical body.

  [...]

  "The multiplicity community's history with the MPD/DID/DDNOS labels is complicated, and full of contention," says Falah Liang [an exponent of this community]. "There's a lot of resentment towards psychiatry for pathologizing what is seen as simply a neurological difference like being left-handed, for painting multiplicity as freaks and invalids, and for pushing integration as a necessary 'cure' that all multiplicity must undergo." On the flip side, the anonymous psychologist I spoke to expressed mild resentment at the idea of healthy/empowered multiplicity distracting from people who actually need a DID diagnosis. "People with DID need to be recognized, as it's a genuine disorder," she said.

  [...]

  Dr. Max Krucoff, a neurosurgery resident at Duke University Medical Center, would be the first to acknowledge the potential slipperiness of DSM diagnoses. "Most medical diagnoses are defined by a pathophysiology—something identifiable, anatomic," he says. "Psychiatric diagnoses have no known underlying cause. I can't take a biopsy of somebody's brain and look at it under a microscope and say, 'You have Multiple Personality Disorder.'"

  Still, the controversial term "disorder," he says, is a means to an end: effective treatment for those who want and/or need it. "If people aren't hurting anybody or dangerous to anybody or asking for help, there's no reason to go looking for them and treating them," he says. "Everybody's on a spectrum, and what's considered a psychiatric illness is often evolving. If you feel like you're sick, if you feel like you need help, then doctors may be able to label you with a disorder only so they can figure out a good way to treat and help you."

And I was going to say that no academic publications have looked at this multiplicity community, but I'm glad to be proven wrong, there's a 2017 paper: "Multiplicity: An Explorative Interview Study on Personal Experiences of People with Multiple Selves" mostly exploring the on-line communities:

  Results: Multiplicity is discussed on Twitter, Tumblr, Google+ and several other personal websites, blogs, and forums maintained by multiples. According to the study's estimates, there are 200–300 individuals who participate in these forums and believe they are multiple. Based on the six interviews, it appears that multiples have several selves who are relatively independent of each other and constitute the personality's system. Each “resident person” or self, has their own unique behavioral pattern, which is triggered by different situations. However, multiples are a heterogeneous group in terms of their system organization, memory functions, and control over switching between selves.

  Conclusions: Multiplicity can be placed along a continuum between identity disturbance and dissociative identity disorder (DID), although most systems function relatively well in everyday life. Further research is needed to explore this phenomenon, especially in terms of the extent to which multiplicity can be regarded as a healthy way of coping.

And a few more details relating to antecedent trauma (or lack thereof),

  Typically, multiples use their unique terminology to refer to common experiences, for example, “system” (which is the term used to refer to themselves, i.e., a system of persons), “resident persons” (or “alters,” who are alternative personalities sharing the body), “fronting” (when one resident person takes control over the behavior in a particular moment or period of time) and “host” (the original personality, often the one who has been present from birth). [...]

  Most systems do not report amnesic barriers or recall traumatic events, and they insist that their multiplicity is something they were born with. Many of them call this healthy or a natural state of identity.

  Multiples are a heterogeneous group. According to their posts, their triggers, how they switch between resident persons and the way they organize real-life behaviors differ greatly from one system to another.

  A recurring topic on forums is the gender identity of multiples. Many multiples experience transgender issues and gender dysphoria because their residents have different genders and sexual preferences. There are many similarities between multiplicity and lesbian, gay, bisexual, transgender, and queer (LGBTQ) rights activism. Multiplicity uses many of the terms that the LGBTQ community uses, such as “coming out,” which means “revealing themselves” to the outside world as a multiple.

The first 3 vignettes (interviews) in the paper do involve antecedent trauma (two of them quite clearly) or report switching being somewhat stress-related. The 4th vignette is perhaps an example where trauma is not involved, but it does involve autism. The 5th vignette is perhaps the one with the least co-morbidity:

  “I'm the host. I'm agender, because I don't like to be identified by gender. We've decided, it's better that I talk because I've been here the whole time,” a 22-year-old female voice introduced herself. She lives in a small town with family and currently studies psychology in college. [...]

  The system started about seven years ago, when the body was 15 years old. “We are not traumagenic; it just happened,” she stated. “In the very beginning, there were only two people who argued. One day I woke up and felt as if someone was possessing me. First I thought that I was losing my mind. It was crazy.” Then, a couple of months later, another person switched in, but it did not communicate with her. A little later, someone else came in and established order. Then, more switched in. There are fairly original members, and there are other ones who gradually showed up.

  Her parents know about the system, but they have never met other members. “My mum asked me if I wanted to kill her,” she stated. Her teachers do not know about her system because she would never allow switching in the classroom. She talked to professionals, and they do not think it is a problem; they see it as a sort of help. Given that she has not had trauma or amnesia, they do not believe it is DID. She added, “It isn't interfering with my life now. On the contrary, it is helpful.”


Can a positive change result in positive stress?

It sounds like you're looking for the word "eustress" or "good stress". Which isn't exactly a label of stress, which as commented is negative, but a positive perception of stress.

My favorite go to example is the positivity often associated with, "challenge accepted!" Here we have a change that is often motivational, difficult, and identifiable as worthwhile.


What research gives insight into the terms "low status" and "high status"?

This is a really broad question - what you seem to be asking is: what research addresses social hierarchies, competition, and neurological/psychological/physiological effects of perception of social status.

It's interesting to note that social status signals likely developed before language, as they are a means of non-verbal communication (language is quite new, evolutionarily-speaking).

In the most broad sense, the answer to your question is that research on social psychology and social neuroscience, particularly that related to hierarchy, dominance, and perception of social standing, is what you're looking for.  This is the 'body of research'.

Past this point, I'm not sure what you're asking...  Are you wondering in what brain structures this type of behavior appears to originate?  Or are you more interested in the cognitive processing going on behind the scenes when people mentally alter their internalized social standing?  Or are you looking for a jumping off point?

If you are particularly looking for the neural basis of this behavior, check out the links below.  All relate to the neurological basis of social processing in the human brain.

Original answer:

I'm at work so I don't have a lot of time to put together a comprehensive answer, but here are some articles:

Perigenual anterior cingulate morphology covaries
with perceived social standing
Know Your Place: Neural Processing of Social Hierarchy in Humans
The Cultural Neuroscience of Person Perception
Using neuroimaging techniques to explore the relationship between social status and health

Neurobiological Correlates of Social Conformity and
Independence During Mental Rotation
Neurobiological Pathways Linking Socioeconomic Position and Health

For the record, the Google search used to find these was neural correlates of perceived social +status


Does the International Affective Picture System (IAPS) contain weapon stimuli?

Use the MAPS https://www.ncbi.nlm.nih.gov/pubmed/26255051

You can request from Auburn Univeristy


Are perceptions of beauty and the ideal partner mostly determined by mass media?

Sexual attraction has mostly but not only a biological roots.
Can this particular woman bear healthy children for me? Do I want this man? Can he be a good father? In a few seconds, someone can evaluate this simply in his/her mind
(evaluate such factors as: height, weight, balance, hips, hair, smell, voice, how healthy the person looks, etc.)
Also, social factors have an influence on our expectations.  Mass media is part of our life, we live in its circle, it forms our culture, makes trends, and influences the path we are making and choices in our life.
The power of influence depends on few factors: the place someone lives (open/close to mass media), the family (all we are from our childhood), and some basic physiological factors we were born with, etc.
Locus of control defines the orientation of a person (internal/external) while choosing the way of living. For some it's more important that their partners are good from the society view (from mass-media view); for others it's not so important.
From Wiki, not very close, but interesting:

Consumer research
Locus of control has also been applied to the field of consumer research. For example, Martin, Veer and Pervan (2007) examined how the weight locus of control of women (i.e., beliefs about the control of body weight) influence how they react to female models in advertising of different body shapes. They found that women who believe they can control their weight ("internals"), respond most favorably to slim models in advertising, and this favorable response is mediated by self-referencing. In contrast, women who feel powerless about their weight ("externals"), self-reference larger-sized models, but only prefer larger-sized models when the advertisement is for a non-fattening product. For fattening products, they exhibit a similar preference for larger-sized models and slim models. The weight locus of control measure was also found to be correlated with measures for weight control beliefs and willpower"

Also there is a good test: Locus of Control .
Your question can be answered simply; it has deep roots and looks interesting for me too. I'll try to find some more modern research to post here.


What functional purpose does a cortical column serve?

I have worked with the theory that the column is the binary unit involved in all cortical processing and memory for many years. Articles are available at my profile page (Robert Moss) at researchgate.net and academia.com. The first article was published in 2006 with an update in 2012. I have published several non-peer-reviewed, more easily understandable articles that are also posted at those sites. One major paper has been recently published that explains the possible microcircuitry of dynamically formed columns.


Why are some people attracted to people of other races?

This is in reply to your first question.

Taste – in food, music, and sex – is in part a result of imprinting. You find women or men attractive that are like your parents or the community you grew up in because of sexual imprinting (e.g. Aronsson, 2011).

Aronsson writes of a sensitive period where this imprinting happens, but I am not so sure that the development of aesthetic taste is actually limited to certain phases in a child's development. Caton et al. (2014) showed that children can acquire the taste for "greens" if they are repeatedly exposed to the food (e.g. having to eat one spoon every time spinach is served). And tobacco, beer, and coffee are prime examples for voluntarily "acquired tastes" later in life. Nevertheless, even an acquired taste is a result of exposure and habituation. Coffee, beer and tobacco are not "exotic" in our culture.

Bem (1996) posited the theory that adults find erotic what was exotic in their early childhood. Thus, a girl that felt different from other girls in childhood would become a lesbian, being attracted to what she was not. This theory has been refuted (e.g. Peplau et al., 1998) on the grounds that it was not supported by empirical evidence.

I could not find anything more substantial in psychological research during a cursory search. What I found are books and articles in cultural theory that look at the popularity of exotic women in the media (e.g. Mendible, 2010). Scanning the contents of those books, I thought that maybe men who are attracted to exotic women are not only attracted to their physical appearance, but also to what these women represent. Thus, Latin women may signify lust for life, African men might stand for physical prowess, Asian women might signify servility, or Oriental women might siginify sophistication and mystery. I'm just quoting some common stereotpyes here as examples for how attraction happens not only on the visual level but also in what we project into the person we desire. Men who like women with glasses might not find them visually beautiful, but might be attracted to the idea of an intelligent or "bookish" and shy person, and this fantasy and eroticsim will even hold despite a contradicting personality.

What I want to suggest with this is that reasons for some kinds of attractions might not be systematic (i.e. the same for a large enought group of persons to discover this connection through empirical studies) but widely different between individuals: one white man loving black women might love them for reasons completely unlike those of any other white man loving black women.

But maybe someone else has the time for a more thorough search and will find a study on this subject.

Sources:

Aronsson, H. (2011). On Sexual Imprinting in Humans. Available online at http://www.diva-portal.org/smash/get/diva2:415143/FULLTEXT01.pdf
Bem, D. J. (1996). Exotic becomes erotic: A developmental theory of sexual orientation. Psychological Review, 103(2), 320. Available online at https://labs.psych.ucsb.edu/roney/james/other%20pdf%20readings/Bem%25201996%2520Exotic%2520becomes%2520erotic.pdf
Caton, S. J., Blundell, P., Ahern, S. M., Nekitsing, C., Olsen, A., Møller, P., ... & Hetherington, M. M. (2014). Learning to Eat Vegetables in Early Life: The Role of Timing, Age and Individual Eating Traits. PloS one, 9(5), e97609. Available online at http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0097609
Mendible, M. (Ed.). (2010). From bananas to buttocks: The Latina body in popular film and culture. University of texas Press.
Peplau, L. A., Garnets, L. D., Spalding, L. R., Conley, T. D., & Veniegas, R. C. (1998). A critique of Bem's" Exotic Becomes Erotic" theory of sexual orientation. Available online at http://folk.uio.no/thomas/gnd/critique-of-ebe-theory.pdf


What is the difference between a psychopath and sociopath?

Ironically enough, Wikipedia does offer as meaningful a distinction as any of the answers here so far:

The term sociopathy may have been first introduced in 1909 in Germany by biological psychiatrist Karl Birnbaum and in 1930 in the US by educational psychologist George E. Partridge, as an alternative to, or a subtype of, the concept of psychopathy.[137] It was used to indicate that the defining feature is violation of social norms, or antisocial behavior, and has often also been associated with postulating social as well as biological causation.[139][140][141][142]
There are various contemporary usages of the term. Robert Hare, who may believe that biological factors are predominant in causing psychopathy,[143] claimed in a 1999 popular science book that sociopathy and psychopathy are often used interchangeably, but in some cases the term sociopathy is preferred because it is less likely than is psychopathy to be confused with psychosis, whereas in other cases which term is used may "reflect the user's views on the origins and determinates of the disorder". Hare contended that the term sociopathy is preferred by those that see the causes as due to social factors and early environment, and the term psychopathy preferred by those who believe that there are psychological, biological, and genetic factors involved in addition to environmental factors.[78] Hare also suggests another possible distinction: he defines psychopathy as not having a sense of empathy or morality, but sociopathy as only differing in sense of right and wrong from the average person.[144][145][verification needed][bolding added for emphasis]

While this largely echoes the existing answers, it includes references to published books and articles, involves the idea's history, and gives the impression that the distinctions between psychopathy and sociopathy are largely in the mind of the authors. They vary somewhat from one author to the next, and don't seem to have much empirical support as distinct diagnoses.
One also ought to question the utility of the proposed distinctions. Secondary psychopathy is also meant to imply social etiology, but also lacks empirical support somewhat. Defining a disorder by violation of social norms is a particularly poor approach to abnormal and clinical psychology, because social norms are typically subjective and ill-defined themselves, and do not necessarily apply outside a contemporary cultural context. Such a definition must possess very limited reliability across time and space.

References
78. Hare, R. D. (1999). Without conscience: The disturbing world of the psychopaths among us. New York: Guilford Press.
137. Rutter, S. (2007). The psychopath: Theory, research, and practice (pp. 37). New Jersey: Lawrence Erlbaum Associates.
139. Partridge, G. E. (1930). Current conceptions of psychopathic personality. The American Journal of Psychiatry, 1(87), 53–99.
140. Felthous, A., & Sass, H. (2008). International handbook on psychopathic disorders and the law, Vol. 1. Wiley.
141. Hildebrand, M. (2005). Psychopathy in the treatment of forensic psychiatric patients: Assessment, prevalence, predictive validity, and clinical implications. Rozenberg Publishers.
142. Partridge, G. E., & Hamblin Smith, M. (1930). Epitome of current literature: Current conceptions of psychopathic disorder. The British Journal of Psychiatry, 76, 838. Retrieved from http://bjp.rcpsych.org/content/76/315/838.1.extract.
143. Ronson, J. (2011). The psychopath test (pp. 225). Riverhead Books.
144. Hare, R. (2006). Snakes in suits: When psychopaths go to work. New York, NY: Harper Collins Publishers.
145. Skilling, T.A., Harris, G. T., Rice, M. E., & Quinsey, V. L. (2002, March). Identifying persistently antisocial offenders using the Hare Psychopathy Checklist and DSM antisocial personality disorder criteria. American Psychological Association.


Why only 16 Jungian types? Combinatorially it should be 2 * 4! = 48

There are not 16 Jungian types. There are 16 MBTI combinations and 16 Kersian (sub-)temperament types. All are related and easily confused.

Jung, in Psychological Types (Collected Works, Book 6), defines two Attitude Types and four functions, splitting the latter into two groups of two.

Attitude Type is Extraversion and Introversion and takes up 9 of the 10 chapters in the work. In the 10th chapter, he explains the four functions: Sensation, Intuition, Thinking, and Feeling. The first two are irrational functions, the second two, rational functions. This makes a total of three groups of two. Though, Jung treats all four functions as one group, it is helpful to remember they can be bifurcated thusly.

Of both the two Attitude Types and the four functions, one is preferred from each. That is, everyone has all the types and functions, but everyone prefers one from each group.

Chapter 10 then explains how the functions play out within the two Attitude Types, leading to 8 explanations, which are Extraversion and Introversion with each of the four functions. He also explains the role of the secondary function. The secondary function will be the opposite of the primary function. That is, if the primary is irrational, the secondary will be rational, and vice-versa.

--

Before Jung published Psychological Types, but based on his works, Meyers-Briggs created the MBTI (Meyers-Briggs Type inventory), a personality inventory based on Jung's functions. The first letter is the preferred Attitude Type, the second letter is the preferred irrational function, the third letter is the preferred rational function, and the fourth letter indicates which function is preferred to be extraverted. Note, the fourth letter does not indicate the primary function. It indicates whether the preferred extraverted function is irrational or rational, which is the inverse of the introvert's primary function.

The combination of one of two Attitude Types, one of two irrational functions, one of two rational functions, and one of two preferred extraverted functions, makes 16 combinations.

In Gifts Differing, Meyers-Briggs defined four function groups (ST, SF, NT, NF) which are like groups to the 16 types.

--

Keirsey, working on Temperament theory (reactions to the external environment), found a connection between his work and the MBTI. Note, he did not find a connection between Temperament and Jung's theory. Indeed, he could not, because Jung did not have the fourth letter defined by the MBTI, which is integral to the connection Keirsey found. He also grouped the letters differently than the MBTI.

Keirsey's groups are SP, SJ, NF, NT, which can be matched to the four historical temperaments: Artisan, Guardian, Idealist, Rational. The history of Temperament theory gives many different names for these groups, so Keirsey, in his main work, Please Understand Me II, says he based it on The Republic. In Keirsey's last work, Personology, however, he focuses much less on those names and uses his own.

With a connection between the MBTI and Temperament theory established, Keirsey extended Temperament theory to include four sub-types for each of the four temperaments. This makes a total of 16 sub-types.


How to restore and maintain a healthy sleep pattern?

Yang et al. (2001) study this exact question. They administered 6 mg of melatonin on Sunday afternoon to subjects that had delayed sleep-wake schedules for the two prior days. They found that

  On Sunday, melatonin administration increased the sleepiness throughout the evening and reduced sleep onset latency at bedtime. On Monday morning, subjective sleepiness was decreased in the melatonin condition.

Kolla & Auger (2011) deal with resetting the internal clock for jetlag and night shift workers. Even though the situation is not identical, I think their main recommendations for adjusting the internal clock are relevant:

  Exposure to bright light in the hours leading up to the patient’s minimum core body temperature tends to push the internal clock later in time, whereas bright light in the hours immediately afterward pushes the clock earlier in time.

(minimum core body temperature is usually 2-3 hours before wakeup time).
So in other words, in order to re-align from wakeup at 1pm to 6-10am one should wake up as early as possible, and go out to be exposed to sunlight (or use an artificial light source).

They also discuss the use of drugs such as melatonin and caffeine.

References

Yang, C. M., Spielman, A. J., D Ambrosio, P., Serizawa, S., Nunes, J., & Birnbaum, J. (2001). A single dose of melatonin prevents the phase delay associated with a delayed weekend sleep pattern. Sleep, 24(3), 272-281. Full text PDF
Kolla, B. P., & Auger, R. R. (2011). Jet lag and shift work sleep disorders: How to help reset the internal clock. Cleveland Clinic Journal of Medicine, 78(10), 675-684. Full text.


Why do people laugh in serious situations?

This could be what the Psychology Today article "Why We Laugh", (Lickerman, 2011) refers to as 'nervous laughter', suggesting that this response is both for reassurance (as suggested by Tyler Langan's comment) and also a means to build resilience in the face of potential trauma, specifically (from the article):

  This may explain why some psychologists classify humor as one of the "mature" defense mechanisms we invoke to guard ourselves against overwhelming anxiety (as compared to the "psychotic," "immature," and "neurotic" defense mechanisms). Being able to laugh at traumatic events in our own lives doesn't cause us to ignore them, but instead seems to prepare us to endure them.

Further, it is suggested here, that the nervous laughter is a means to protect our dignity and sense of control.


What is the function of the connection between the two halves of the thalamus?

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

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

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

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

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

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


Do you need to pay an extra $300 to be able to retrieve data from the Emotiv Epoc via the python-emotiv library?

For the non-eeg emotiv Epoc, the SDK only offers to retrieve the actions and their values detected from the device. But no raw data.


What is the name of the cognitive bias where an expert overestimates the knowledge of others?

This sounds similar to the "curse of knowledge" phenomenon (also called the "curse of expertise" by at least one publication that I found).

From Wikipedia:

"The curse of knowledge is a cognitive bias according to which better-informed people find it extremely difficult to think about problems from the perspective of lesser-informed people."

Some references:

Camerer, C., Loewenstein, G., & Weber, M. (1989). The curse of knowledge in economic settings: An experimental analysis. The Journal of Political Economy, 1232-1254.
Birch, S. A., & Bloom, P. (2007). The curse of knowledge in reasoning about false beliefs. Psychological Science, 18(5), 382-386.
Hinds, P. J. (1999). The curse of expertise: The effects of expertise and debiasing methods on prediction of novice performance. Journal of Experimental Psychology: Applied, 5(2), 205.


How are the outputs of neurons encoded, if at all?

The concept of digital channels of information flow is a serial-processing biased view of information: it applies a lot to serial systems like computers (which are still serial even with multiple "cores" since each operates independently of the other), but does not apply in the same way to massively parallel systems like the nervous system except perhaps to some very of the very low-level sensory information.

However, temporal coding has been a very active area of research. There are many different time scales on which neurons can potentially carry timing information. However, a digital bit stream is probably the least efficient one so you won't find much from neuroscience suggesting that type of pattern.

External timing is very important

Even given a very simple "analog-ish" neural code, where firing rates indicate some intensity of signal (for example, the tension on a tendon), there is also key temporal information to carry: the tension is happening now. It is not on a stack to be processed and conveyed in the most efficient encoding possible, it is happening presently, and the neuronal signal has to encode not just how much but also that it is occurring now: rate codes can do this to a fairly high precision.

Neuronal firing is a bit like a Geiger counter: the intensity is indicated by the rate of clicks, but there is a ton of additional information based on when those clicks occur. For example, as you move a Geiger counter nearer to a radiation source, the click rate increases dramatically. Any code that is more complex would introduce delays, and those delays necessarily result in a loss of temporal information.

Phase coding

Within the brain, there are definitely cases where temporal information is important to neural codes. The brain handles more complex information that changes over longer time scales than in the periphery, so it is possible to degrade temporal information to allow for deeper encoding schemes that combine generative models of the outside world with abstracted sensory information.

In particular, one can look at phase coding where neurons fire at a particular phase of an ongoing oscillation (Montemurro et al, 2008; Kayser et al, 2009). You could perhaps think of the ongoing oscillation as a "timing bit" because it provides a synchronizing point for relative timing of spikes.

In the hippocampus, phase coding is important for reconstruction of position information from neural spiking activity (O'Keefe et al, 1993; Jensen and Lisman, 2000).

Ensemble coding

Imagine a cortical neuron fires up to 100 Hz. You could digitize a signal by looking at spike/no spike within 10 ms bins, so every 10 ms you have 1 bit of information per neuron. Take an ensemble of 100 independent neurons, and you have 100 bits per 10 ms or 10,000 bits per second.

However, if you instead of 100 members of an ensemble, each 10 ms encodes not 1 * 100 bits, but 2^100 which is on the order of 1030 patterns every 10 ms. And this is without assuming a more complex temporal code where the order of firing within a brief window matters (Abeles et al, 1993).

There is good evidence that overlapping cell assemblies/ensembles exist (see for example Harris, 2005 for review) such that at any moment in time, the high-dimensional activity over the space of many neurons carries information, for example about the current sensory state.

Given that there are billions of neurons in a brain, ensemble coding makes bit rate not itself a limiting factor, though other constraints seem to make phase coding and other types of temporal info

Abeles, M., Bergman, H., Margalit, E., & Vaadia, E. (1993). Spatiotemporal firing patterns in the frontal cortex of behaving monkeys. Journal of neurophysiology, 70(4), 1629-1638.

Harris, K. D. (2005). Neural signatures of cell assembly organization. Nature Reviews Neuroscience, 6(5), 399.

Jensen, O., & Lisman, J. E. (2000). Position reconstruction from an ensemble of hippocampal place cells: contribution of theta phase coding. Journal of neurophysiology, 83(5), 2602-2609.

Kayser, C., Montemurro, M. A., Logothetis, N. K., & Panzeri, S. (2009). Spike-phase coding boosts and stabilizes information carried by spatial and temporal spike patterns. Neuron, 61(4), 597-608.

Montemurro, M. A., Rasch, M. J., Murayama, Y., Logothetis, N. K., & Panzeri, S. (2008). Phase-of-firing coding of natural visual stimuli in primary visual cortex. Current biology, 18(5), 375-380.

O'Keefe, J., & Recce, M. L. (1993). Phase relationship between hippocampal place units and the EEG theta rhythm. Hippocampus, 3(3), 317-330.


What is the capacity of the human brain?

Paul Reber, professor of psychology at Northwestern University, stated that

  The human brain consists of about one billion neurons. Each neuron forms about 1,000 connections to other neurons, amounting to more than a trillion connections. If each neuron could only help store a single memory, running out of space would be a problem. You might have only a few gigabytes of storage space, similar to the space in an iPod or a USB flash drive. Yet neurons combine so that each one helps with many memories at a time, exponentially increasing the brain’s memory storage capacity to something closer to around 2.5 petabytes.

1PB = 1,000,000,000,000,000 B = 1015 bytes = 1000 TB (terabytes).1TB = 1,000,000,000,000 bytes = 1012 bytes = 1000 GB (gigabytes). So2.5PB = 2.5 million gigabytes

  For comparison, if your brain worked like a digital video recorder in a television, 2.5 petabytes would be enough to hold three million hours of TV shows. You would have to leave the TV running continuously for more than 300 years to use up all that storage.

The same article states that although it is stated that the brain is capable of storing around 2.5PB of information,

  The brain’s exact storage capacity for memories is difficult to calculate. First, we do not know how to measure the size of a memory. Second, certain memories involve more details and thus take up more space; other memories are forgotten and thus free up space. Additionally, some information is just not worth remembering in the first place.


Crosstalk needs to be taken into consideration, but with reasonable controls it can be made insignificant. Interaural attenuation can vary between less than 40 dB to over 60 dB depending on frequency, the type of headphone, and how well it is coupled to the head. If you have 40 dB of interaural attenuation and present the sounds at less than 40 dB SL (sensation level) the cross talk will be inaudible. The further below threshold, the better off you are.

If you need to present the sounds at a level greater than the amount of interaural attenuation, crosstalk will still not matter if the other sound provides sufficient masking or you introduce sufficient masking noise. For dichotic speech tasks, the speech masks the crosstalk. For musical tones, you might need to introduce a masking noise depending on the frequency content of the tones.

It may be easier to simply spatially separate the stimuli by either presenting them over loudspeakers or using head-related transfer functions (HRTFs) and presenting them over headphones. In the original work of Broadbent (1954) he used a number of different configurations while Cherry (1953) only used headphones and presented each stimulus monaurally.


How do reward signals strengthen synaptic connections in the human brain?

dopamine release changes the nature of synaptic long term potentiation (ltp) thought to underly long term memory. see http://www.sciencedirect.com/science/article/pii/S0896627305003971 for a paper i am familiar with, for an entry point to that field

for a review article:
http://www.nature.com/nrn/journal/v5/n6/abs/nrn1406.html
see section titled "Dopamine and memory at the cellular level"


Memory impairments are connected to fluid inteligence... read this:
http://www.ncbi.nlm.nih.gov/pubmed/16206235

Also consider that stress and ageing decrease fluid inteligence. In addition you said that you care less to solve... it is motivational not cognitive problem.

for real conclusion try to find if you did take any inteligence test (with norms) and try to visit clinical psychologist to compare your new result to old result.

Result from clinical psychologist is most important because maybe you have only impression.


How do people with a split brain experience reality?

The corpus callosum is the largest of the commissural neural pathways, linking the cerebral cortex of the left and right hemisphere. The sectioning of this tract is called a corpus callosotomy, which disconnects the two sides of the neocortex.

A callosotomy is used in cases of intractable epilepsy, i.e., epilepsy that cannot be treated sufficiently with medication.

Patients with their corpus callosum severed have been shown to have difficulties in tasks that require lateralized brain areas to work together. For example, the left visual field is processed in the right hemisphere in the brain (and vice versa), speech and language centers are primarily located in the left hemisphere (in most people) and the right hemisphere specializes in visual-spatial processing and facial recognition.

When experiments are done under laboratory conditions, the lateralization of the brain becomes quite evident in these patients. For instance, a compelling experiment is shown in Fig. 1. When a split-brain subject is shown a word in the right field of view, the image is processed in the left hemisphere in the brain. The case shown shows the typical case where the language centers reside in the left hemisphere too. In this case, the subject is able to say what the word was ('face'). However, when the same word is shown on the left, the visual image is processed in the right hemisphere, where the speech centers are less well represented, if at all. In this case the subject cannot verbalize what they saw, but they are able to draw it(!). And in fact, subjects may say they saw nothing at all when a visual stimulus is presented on their left side, but still make a motor response to it (e.g., press a button when instructed to do so when a stimulus pops up).

Fig. 1. Split brain experiment. source: Nature

Why does callosotomy help epilepsy patients? When conventional methods fail to treat severe forms of epilepsy (intractable epilepsy), sectioning the corpus callosum may help to prevent the seizure from spreading from one hemisphere to the next. Generalized seizures result in loss of consciousness only when both hemispheres are affected. Often, seizures start in a hot spot, called an epileptic focus. From there it spreads over the cortex and the subject gradually loses consciousness. Once it jumps over, via the corpus callosum, the subject loses consciousness entirely. Hence, severing the major connection between the two hemispheres can keep seizures from evolving into full-blown generalized seizures. However, callosotomies have been really rare in the past and they are hardly performed today, due to the advances made in anti-epileptic drug development, combination therapies, micro surgery, etc.

Resource
- Nature News, March 2012


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

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

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

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

A few points paraphrased from the paper:

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


Which brain areas are linked to Hyperactivity in ADHD?

I think the studies that you were after have only recently been published earlier this year. 38 subjects with ADHD had fMRI scans and compared with a database. The study found that -

  More severe hyperactivity was associated with increased functional connectivity in the left putamen, right caudate nucleus, right central operculum and a portion of the right postcentral gyrus within the auditory/sensorimotor network.More severe hyperactivity was associated with increased functional connectivity in the left putamen, right caudate nucleus, right central operculum and a portion of the right postcentral gyrus within the auditory/sensorimotor network.
  https://bmcpsychiatry.biomedcentral.com/articles/10.1186/s12888-019-2031-9


Why do dual N-back games use certain letters?

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

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

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

(emphasis mine).

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

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


The researchers that developed this task decribe it in DeVito et al. (2009) as follows:

Information Sampling Task
The IST (Clark et al. 2006) is a measure of ‘reflection–
impulsivity’. Subjects were told they would be presented
with ten trials in each of two conditions [fixed win (FW),
decreasing win (DW)] and that the task would last for
10 min. On each trial, a 5×5 matrix of grey boxes with two
larger coloured panels below it was presented. Subjects
were told to press on a box to reveal its colour and to open
as many boxes as they chose prior to deciding which of the
two colours they thought was in the majority amongst the
25 boxes. Boxes remain open for the duration of the trial to
minimise working memory load. To register their decision,
they pressed on one of the two coloured panels displayed.
In the FW condition, if the subject chose correctly, they
earned 100 points, but lost 100 points if they chose
incorrectly. In the DW condition, subjects begin with the
ability to win 250 points, but with every box they opened
the amount they could win decreased by 10 points. An
incorrect choice was still penalised with a loss of 100 points
regardless of the amount of boxes opened. Therefore, in the
FW condition, extensive information sampling prior to
decision was optimal, whilst in order to gain points in the
DW condition the subject must adjust to sample less
information. A variable inter-trial interval was used such
that the minimum trial duration was 30 s (e.g. if the subject
responded after 10 s, the inter-trial interval would be 20 s).
This feature was included to prevent unduly rapid responses
leading to shorter task duration and thus an earlier escape of
the experimental setting. This task is described in more
detail by Clark et al. (2006).

In Clark et al. (2006), they write:

In the present study, we used a novel Information Sampling Task (IST) to assess reflection impulsivity in chronic substance users. The objectives of the IST design were to derive a primary index of information sampling (rather than a speed–accuracy composite) in a task that placed negligible demands on visual processing and working memory. The IST presents a series of trials with an array of 25 grey boxes arranged in a 5 × 5 matrix. The grey boxes conceal an underlying assortment of squares (e.g., yellow and blue; Figure 1) on each trial. The subject was asked to decide which of the two underlying colors (yellow or blue) lay in the majority. The subject was able to open as many boxes as they wished to make that decision. Once opened, boxes remained visible for the duration of the trial to obviate working memory demands. Correct decisions were awarded a number of points, with trials blocked into two conditions. In the Fixed Win (FW) condition, a correct decision yielded 100 points, irrespective of the number of boxes opened. In the Decreasing Win (DW) condition, the number of available points decreased with every box opened. Consequently, the DW condition introduced a conflict between reinforcement and certainty: to maximize reinforcement the subject must tolerate high uncertainty, whereas sampling information until a point of high certainty would win very few points. Given preliminary evidence that drug users might be hypersensitive to reward (Bechara et al 2002 and Garavan and Stout 2005), we predicted that the DW condition would encourage impulsive responding and exaggerate individual differences.

Figure 1. Screen display for the Information Sampling Task. Each trial commences (left) with the presentation of 25 grey boxes arranged in a 5 × 5 matrix, covering a random assortment of two colors of squares; these two colors are displayed on panels at the foot of the screen. When the subject touches a box (middle), it opens to reveal its color. The subject must decide which of the two colors lies in the majority on the board. They are told they can open as many boxes as they wish to make this decision. They are told to touch the corresponding panel at the foot of the screen (bottom right) once they have decided which color is in the majority.

In addition, there is a description of the Information Sampling Task in the Cognitive Atlas.
References

DeVito, E. E., Blackwell, A. D., Clark, L., Kent, L., Dezsery, A. M., Turner, D. C., ... & Sahakian, B. J. (2009). Methylphenidate improves response inhibition but not reflection–impulsivity in children with attention deficit hyperactivity disorder (ADHD). Psychopharmacology, 202(1-3), 531-539.

Clark, L., Robbins, T. W., Ersche, K. D., & Sahakian, B. J. (2006). Reflection impulsivity in current and former substance users. Biological psychiatry, 60(5), 515-522.


Which personality trait(s) characterize high need for external validation?

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

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

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

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


Scientific name for the phrase: "The first image is the image that stays"

There is another common expression: "You never get a second chance to make a first impression."

The stability of first impressions is empirically sound:

  Once formed, first impressions tend to be stable. A review of the
  literature on the accuracy and impact of first impressions on
  rater-based assessments found that raters' first impressions are
  highly correlated with later scores, but it is unclear exactly
  why. One study tested stability by asking participants to form
  impressions of people based purely on photographs. Participants' opinions
  of the people in the photographs did not significantly differ after
  interacting with that person a month later.

One possible explanation is a well-known and empirically supported cognitive bias called the "anchoring and adjustment heuristic".  It seems that people form initial impressions (anchoring), then on subsequent evaluations only make adjustments to the initial impressions, and these adjustments tend to be insufficient.  The cause of anchoring is also not well understood.

A more general explanation is "confirmation bias" (anchoring, self-fulfilling prophesy, and the halo effect are all subtypes of this bias), where people form initial impressions, and then confirm their impressions on subsequent evaluations by focusing on information that supports them, and avoiding, ignoring, forgetting, and distorting any information that does not.  This is a very empirically robust bias.


Can memorising a new thing erase existing memories?

Although this is quite an old question, I thought I would add additional
information regarding this topic for consideration.

As already noted, the storage capacity of the human brain is certainly very impressive. However, there are also some interesting quirks to human memory worth noting.

  does memorising a new thing increase the chance of losing existing memories that are not directly related to the new memory (different subjects)?

No -- and in fact, when something approaching the phenomenon you are describing occurs, quite the opposite appears to be true.

Before I clarify this, it's important to note that one should not think of memory as something that is "lost" in the same way that one might record over a VHS cassette tape and lose the old content in the process.

When one encodes new information ("learns a new factoid"), there is a greater chance of that new information adversely affecting their ability to retrieve and recall semantically related memories.

Memory interference is more likely to occur with similar material than different material.

Two main types of interference are thought to affect memory:

Proactive interference. Previously learned information affects our ability to recall newly learned information.

Retroactive interference. Newly learned information affects our ability to recall earlier learned information.

In effect, what you might observe is precisely the opposite of what you are suggesting in your original question: when you memorise information about a "different subject" you are in fact less likely to "lose existing memories" relative to memorising information about the "same or similar subject".

Again, it's important to recall that you're not actually overwriting or erasing the older memories, but more likely merging them together and confusing them with other memories.

This has relevance to how one might chose to structure their learning e.g. revise for exams. After revising organic chemistry, one might derive greater benefit from subsequently revising a foreign language, rather than say, following it with inorganic chemistry.

So, as it relates to your Simpsons reference, the following would be more likely to be correct:

  Remember that time I took a home wine-making course and forgot how to drive brew beer?

Below is a screenshot from a introductory psychology textbook detailing describing the role of interference in forgetting. It also refers to empirical research supporting the phenomenon:

From: "A Level Psychology Through Diagrams" By Grahame Hill
(My apologies, I had to use my undergrad textbooks in a bonfire when I was homeless and had been reduced to eating catfood)


Why is the order of brainwaves not labelled "alphabetically"?

They are ordered based on when they were discovered/named (as pointed about by Ana's comment). Alpha and beta waves were among the first signals observed in EEG data. From Wikipedia:

  Alpha waves were discovered by German neurologist Hans Berger, most famous for his invention of the EEG. Alpha waves were among the first waves documented by Berger, along with beta waves, and he displayed an interest in "alpha blockage", the process by which alpha waves decrease and beta waves increase upon a subject opening their eyes. This distinction earned the alpha wave the alternate title of "Berger's Wave".

Hans Berger documented alpha and beta waves in a series of articles from 1929-1933.

Gamma waves took a few more decades to identify, because the higher frequency necessitates faster sampling. The earliest EEG systems were unable to measure oscillations at such fast frequencies.


Have EEG signals in auditory speech perception task have ever been analyzed for correlation with auditory stimuli itself?

Extensively. Most prominently, recently, by David Poeppel, Oded Ghitza and Anne-Lise Giraud, in a series of papers. They've, to be precise, mostly focused on MEG  correlations with the filtered speech amplitude envelope. Areas around the auditory cortex track it fairly well it seems. There is still much debate about what this means and where it comes from, but it's been discussed. Example here.

There is also the spectrotemporal response function, which is a somewhat generalized concept and mostly employed in an sEEG context. Example here. It looks like this:


give me concrete example of mindless and mindful activity

I'm not sure that a "concrete example" of mindless activity vs. mindful activity is possible, because it requires the use of subjective interpretations of what constitutes either of those two notions.

Mindfulness

  Mindfulness is a state of active, open attention on the present. When you're mindful, you observe your thoughts and feelings from a distance, without judging them good or bad. Instead of letting your life pass you by, mindfulness means living in the moment and awakening to experience.

https://www.psychologytoday.com/basics/mindfulness

Using this definition, it seems as though there are relatively few activities one can perform while being mindful. If an activity requires a high level of concentration to perform, than it would be difficult or impossible to simultaneously focus on the meditative internal and external reflection implied by 'mindfulness.'

Examples of some activities that might be more favorable to such meditation:

Going for a walk or hike somewhere
Going to a quiet, secluded location
Doing chores around the house that require little concentration

Examples of some activities that might not be favorable to such meditation:

Socializing
Working on a task that requires a lot of concentration or creative problem-solving
Watching an interesting movie or reading an interesting book, (unless perhaps you pause for self-reflection from time to time.)

Mindlessness

This is also tricky because it may mean different things to different people. Mindlessness might mean simply the opposite of mindfulness, in which case the counter-examples I listed above might be considered 'mindless.'

However, it seems a bit strange to include things like creative problem-solving and socializing as a "mindless" activity; because your mind is absolutely engaged in what's going on, just not in the same sense as it is for a mindful / introspective reflection.

Perhaps a fair definition of "mindlessness" is if you're by yourself with some free time; instead of choosing to engage in some social and/or mental activity, or meditate in a mindful way, you just sit around; being bored, thinking about how boring something is, etc.

Yet even "mindlessness" with it's negative connotations may have some importance. Sometimes when you're undergoing great stress, mindful meditation may be good and useful but you're not ready to do it; you may need to distract yourself from something that's troubling you. You might have to try something "mindless" to clear your head a bit before you can even be "mindful."

Conclusion

The truth is; the human brain never truly slows down while you're alive. There's a persistent myth that we only use 10% of our brain; but while it's true that only portions of our brain are active at any given moment, we actually use 100% of our brain, just not all at the same time. It would be destructive and/or impossible to use 100% of your brain at once, that's not how the brain is designed to work. http://ed.ted.com/lessons/what-percentage-of-your-brain-do-you-use-richard-e-cytowic

In this sense, the question of "mindfulness vs. mindlessness" isn't necessarily about whether or not you're using your mind. You use your mind regardless, even in your sleep. The question becomes whether or not you're using your mind well, and that ultimately is a personal, subjective question.

The closest I can say to understanding it objectively is that it's probably healthiest to strive for balance in how you live your life.


Who first used the term 'heuristic' in a cognitive science context?

A nice summary about heuristics can be found in:

Gigerenzer, G., & Gaissmaier, W. (2011). Heuristic Decision Making. Annual Review of Psychology, 62, 451–482.

In this review "satisficing" (accepting a good enough option) is referred to an earlier reference than the 1958 you cite:
Simon, H.A. (1955). A behavioral model of rational choice. Q. J. Econ. 69:99–118.

In their (Gigerenzer & Gaissmaier) history part they also refer to Einstein using the term in his 1905 paper on quantum physics, stating that the view he presented was "incomplete but highly useful".


Satisfaction from music due to correct prediction of a sound

That's pretty much the core argument of
"On the joys of perceiving: Affect as feedback for perceptual predictions" (2015) Chetverikov & Kristjánsson.
It's a fun read, I think you might enjoy it.

Obviously music and other arts pull a bunch of other affect levers as well, not just this one. And "correct predictions" might not be the best way to characterize this particular lever: maybe the pleasure comes from being predictive rather then predictable
cf. Braem, Senne, and Trapp (2019) "Humans show a higher preference for stimuli that are predictive relative to those that are predictable."
Familiarity with a music style confounds the two, they both go up as you get a feel for the style. There's obviously something going on with curiosity/exploration/novelty also being pleasurable, but I don't think it's clear yet if you get that 'for free' with the predictive account or if an intrinsic reward for exploration should be its own thing.

Anyway, long story short there's some literature that looks a lot like your 'random vague idea', it's incomplete ongoing work, but it sure looks like it might be going somewhere interesting. Enjoy!


Are there any serious neuroscientific theories of emotional valence?

There is no such universally accepted model.  It seems to me that this a specific instance of the hard problem: how can matter have a subjective experience at all?

Of course we know positive experience is associated with dopaminergic action, and often the mechanism has the evolutionary function of surviving and reproducing... and we can argue the same for noxious stimuli - they signal danger in the environment and lead to aversive behaviors.

But this still ignores the phenomenology step, between stimulus and behavior; the nature of the subjective experience.  Friston's approach is interesting.  I wonder if there is any relationship to be found betweem it and Tononi's model of consciousness (integrated informatiom theory).


Does the concept of employee engagement add anything over and above traditional concepts?

A few basic observations:

Typical self-report measures of engagement and job satisfaction tend to be highly correlated (I'll try to find a reference later, but I think in the r =.7 range).
As with many organisational psychology terms that bridge the scientific-practitioner divide, engagement has been operationalised in a wide range of ways.
Volume 1, Issue 1 of Industrial and Organizational Psychology has a focal article and a large set of accompanying commentaries on the meaning of engagement and its value as a concept. See this pdf of the focal article.


Correct measure of central tendency for reaction times analysis

You can find an accessible overview of some of the issues in Whelan (2008) which contains further references discussing the issue.
Note that from a statistical perspective,  the sample mean and median are unbiased estimators of their population equivalents. That said, with outliers, skew and the like, the standard error of the sample mean can be quite a bit larger than the sample median. Furthermore, you typically the population distribution should be seen as a multiple component mixture distribution (e.g., fast guess trials, "real trials", distracted trials). In such cases, you may be particularly interested in the central tendency of the "real trial" distribution. In that case, sample mean and median may be biased estimates of "real trial" equivalent population distributions.

Whelan (2008) suggests the following in order of preference when estimating a measure of central tendency:

Mean after trimming the raw data for outliers (i.e., taking the middle 85% to 95% of RT data)
Mean of log or negative inverse transformation of raw reaction time
Median of raw RT

That said, the justification for a given method depends on the underlying distribution of the data and the nature of the effect of condition. For example, if condition is mainly influencing prevalence of outliers or skew, this will effect the mean more than the median in the population.

A good general strategy for exploring these issues and justifying your decision is to estimate central tendency in reaction times using a range of methods. Then correlate the scores you get for each individual using the different  methods. If you are getting very high correlations (e.g., r>.95 or .99) then you will know that the method makes little difference.

Whelan (2008) also discusses strategies for estimating all parameters in the RT distribution.

If you are studying choice reaction time, then LBA or Ratcliff's diffusion model may be more appropriate.

References

Whelan, R. (2008). Effective analysis of reaction time data. The Psychological Record, 58, 475-482. PDF


What would happen if we cut the corpus callosum?

Basically the same as a normal two-halved brain. Circumstances in which function is altered are fairly limited. For details, see case reports on Wikipedia's split-brain page, and this episode of Scientific American Frontiers that features Mike Gazzaniga's research, as mentioned here. Gazzaniga's research was reviewed in a Nature news feature (Wolman, 2012), which you may also find helpful.

Also, yes to all questions of control, except maybe hearing...not sure how we control that normally, other than in terms of attention (see "Do we only hear what we want to hear?"), which still operates normally AFAIK. Control breaks down unusually in mostly special circumstances where stimuli are presented to only one side of the brain. Both ears usually hear most sounds, and both eyes' fields of vision overlap quite a lot, so these circumstances need to be created experimentally to demonstrate really clear effects.


Calculating brain-part volume percentage?

Short answer
Magnetic resonance imaging can be used to calculate volumes of brain areas.

Background
A state-of-the-art method to determine volumes in brain tissue is by making use of magnetic resonance imaging (MRI). MRI segments the brain into 3D pixels, called voxels. Voxel is derived semantically from the fusion of pixel and volume. Hence, each voxel has a certain volume and thus the number of voxels inside a certain brain area (e.g. the hippocampus) can be calculated yielding your desired volume measures (Fig. 1).

Of course you cannot do MRI in your attic, but you can search the internet for the right articles. Two leads are cited below.

Fig. 1. Brain divided into voxels by MRI. source: Everything Zoomer

References
- Andica et al., J Neuroradiol (in press)
- Aquartz et al., Eur Arch Psychiatry Clin Neurosci (2001);251(6): 255-61