Do repressed memories exist? Is there such a thing as repressed memories? Suppose a person undergoes a traumatic event (e.g failing out of school, having a relative die suddenly). Is it normal for the person to act as if everything is normal? Do the traumatic events have an affect on someone even if they dont think about it every day?

Within the limbic system the hippocampus and  amygdala processes  memory.

hippocampus
The hippocampus processes declarative memory, the memory  recalled in the form of thought and stores memory.

  Hippocampal integrity plays a crucial role in intact memory functioning. Research has demonstrated that normal hippocampal development continues into early adulthood . Investigators specifically examining the development of the hippocampus have suggested that the hippocampal formation undergoes a steep increase in volume until approximately the second year of life, then the volume slowly increases throughout adolescence. 1

amygdala
The amygdala processes emotional memory by directing the stimulus to emotional.

  here is extensive evidence that the amygdala is involved in affectively influenced memory. The central hypothesis guiding the research reviewed in this paper is that emotional arousal activates the amygdala and that such activation results in the modulation of memory storage occurring in other brain regions.
  2

development of amygdala and hippocampus
The hippocampus and amygdala   are not fully developed until the ages of 9-11 years of age. there is evidence in studies that this development continues into early adulthood

  significant age-related changes in the volumes of amygdala and hippocampus. The developmental trajectories of the brain regions were best characterized by the cubic model, which demonstrated robust changes in the beginning of life, with the amygdalar and hippocampal volumes peaking around 9 to 11 years of age,..
  The results of the present study indicated that the maximum volume of the amygdala was reached between 9 and 11 years of age. 3

The amygdala is able to effective process emotional memory, independently of attention.

  The question addressed in this paper is whether the human amygdala processes threat-related stimuli independent of selective attention. This is considered from a functional neuroimaging perspective, describing studies in normal volunteers and patients with brain lesions. The conclusion is that the evidence for such automaticity is strong, indicating that important distinctions exist between emotion and other forms of cognition  4

The hippocampus, requires attention to process and recall memory.

  The hippocampus is critically involved in storing explicit memory such as memory for space. A defining feature of explicit memory storage is that it requires attention both for encoding and retrieval.  5

In conclusion:
As the parts of the brain that process memory are forming during the early years of life, given that emotional memory is more readily processed than declarative memory. It is possible to have experiences within the emotional memory, that have not got clear cut conscious memories.
This post about involuntary memory, discusses memory retrieval in a little more detail.

1. Abnormal Hippocampal Development in Children with Medulloblastoma Treated with Risk-Adapted Irradiation
Bonnie J. Nagela,g, Shawna L. Palmera, Wilburn E. Reddickb,f, John O. Glassb, Kathleen J. Heltonb, Shengjie Wuc, Xiaoping Xiongc, Larry E. Kunb, Amar Gajjard,e and Raymond K. Mulherna
2. Involvement of the amygdala in memory storage: Interaction with other brain systems
James L. McGaugh, Larry Cahill, and Benno Roozendaal
3. Uematsu A, Matsui M, Tanaka C, Takahashi T, Noguchi K, et al. (2012) Developmental Trajectories of Amygdala and Hippocampus from Infancy to Early Adulthood in Healthy Individuals. PLoS ONE 7(10): e46970. doi:10.1371/journal.pone.0046970
Ann N Y Acad Sci. 2003 Apr;985:348-55.
4. Amygdala automaticity in emotional processing.
Dolan RJ, Vuilleumier P.
Source
Wellcome Department of Imaging Neuroscience, Institute of Neurology, London WC1N 3BG, UK. r.dolan@fil.ion.ucl.ac.uk
5. What is remembered? Role of attention on the encoding and retrieval of hippocampal representations
Isabel A. Muzzio, Clifford Kentros and Eric Kandel


Why do the hemispheres of the brain control the opposite sides of the body? History of question: This previous question asked about both hemispheric specialisation and control of opposite sides of the body. The point was made that these are two very different questions. So the original question has been reduced to the specialisation topic, and the "opposite sides" question is asked here.

So the question here is:

Why do the hemispheres of the brain control or receive sensory input from the opposite sides of the body? What is the benefit or purpose of this?

The formal name for crossing in biology is decussation.  It is thought to be a result of anatomical development as well as a recovery mechanism.  Essentially, it's an emergent result of negotiations between genetics, development, and environment.  I've emphasized the relevant sentences in two abstracts below.

  Abstract: The crossing of nerve tracts from one hemisphere in the brain to the contralateral sense organ or limb is a common pattern throughout the CNS, which occurs at specialised bridging points called decussations or commissures. Evolutionary and teleological arguments suggest that midline crossing emerged in response to distinct physiological and anatomical constraints. Several genetic and developmental disorders involve crossing defects or mirror movements, including Kallmann's and Klippel-Feil syndrome, and further defects can also result from injury. Crossed pathways are also involved in recovery after CNS lesions and may allow for compensation for damaged areas. The development of decussation is under the control of a host of signalling molecules. Growing understanding of the molecular processes underlying the formation of these structures offers hope for new diagnostic and therapeutic interventions.

Vulliemoz, S., Raineteau, O., & Jabaudon, D. (2005). Reaching beyond the midline: why are human brains cross wired?. The Lancet Neurology, 4(2), 87-99.

  Abstract: Many vertebrate motor and sensory systems “decussate” or cross the midline to the opposite side of the body. The successful crossing of millions of axons during development requires a complex of tightly controlled regulatory processes. Because these processes have evolved in many distinct systems and organisms, it seems reasonable to presume that decussation confers a significant functional advantage—yet if this is so, the nature of this advantage is not understood. In this article, we examine constraints imposed by topology on the ways that a three-dimensional processor and environment can be wired together in a continuous, somatotopic, way. We show that as the number of wiring connections grows, decussated arrangements become overwhelmingly more robust against wiring errors than seemingly simpler same-sided wiring schemes. These results provide a predictive approach for understanding how 3D networks must be wired if they are to be robust, and therefore have implications both for future large-scale computational networks and for complex biomedical devices.

Shinbrot, T., & Young, W. (2008). Why decussate? Topological constraints on 3d wiring. The Anatomical Record, 291(10), 1278-1292.


Why is a cross-dominant/ambidextrous brain more susceptible to mental illness? The left and right hemispheres of the brain are connected by a bundle of fibers called the corpus callosum. Ambidextrous, left handers and cross-dominant people have symmetrical brains as opposed to right handers, who have larger left hemispheres. Cross-dominant, lefties and ambidextrous people also have a stronger corpus callosum which lends itself to better communication between the two hemispheres. It seems like better communication between hemispheres would be an evolutionary benefit.

So, I am curious as to why a symmetrical brain would have a higher rate of mental illness than a right handed/left brained person, as reported in this news release by Imperial College London: Mixed-handed children more likely to have mental health, language and scholastic problems, say researchers

This question is still a little broad...

On the issue of corpus callosum (CC) and mental illness, it's not clear that this follows the same pattern as ambidexterity. Highley et al. (1999) found that there fewer fibers in CC of women with schizophrenia:

  A reduction in the total number of fibres in all regions of the corpus callosum except the rostrum was observed in female schizophrenic patients (P = 0.006; when controlling for brain weight, P = 0.053). [...]  With age, all subregions of the corpus callosum except the rostrum showed a significant reduction in cross-sectional area (P = 0.018) and total fibre number (P = 0.002).

They also found "little change in the males".

In fact the press release you linked does not mention corpus callosum.

So whatever common factor drives ambidexterity and mental illness, it doesn't seem a simple as the (higher) number of fibers in CC.

Also, cross-dominance is a broader concept when it comes to the brain; the press release doesn't mention this term either. Even though Wikipedia considers it synonymous with mixed-handedness, one can have a cross-dominant vision but not cross-dominant handedness, for example. And in fact some of the more recent research has pointed out to different correlations with mental illness of these various types dominance, e.g.:

  The rate of left or mixed-footedness, eye dominance, and any anomalous lateralization, but not handedness, discriminated between those who developed schizophrenia spectrum disorders and those who did not.

Of course they might not have had enough statistical power to detect it (for handedness.) But also a mini-review of prior work on this in the same paper points to somewhat contradictory conclusions, even for handedness, but still says that

  The preponderance of evidence, however, supports the hypothesis that
  schizophrenia patients are more often left or mixedhanded compared to controls. Left or mixed-handedness in schizophrenia may indicate abnormalities in
  neurological structure or functioning.

Interestingly this issue of failing to detect the effects of dominance in handedness has been encountered before:

  Several cohort studies have measured childhood
  laterality as it relates to later risk for schizophrenia
  (e.g., Crow et al., 1996; Cannon et al., 1997). Crow
  et al. investigated handedness in the National Child
  Development Survey, a study assessing all individuals
  born in the United Kingdom during a single week
  in 1958. Mothers of children who later developed
  schizophrenia were more likely to rate their children
  as ambidextrous at age 7 as compared to mothers of
  children who did not develop schizophrenia. Additionally,
  children who eventually developed schizophrenia
  were less strongly right-handed than controls
  at age 11.

  Cannon et al. (1997) studied laterality in a total
  population of 5362 children born in England, Scotland,
  and Wales during one week in March 1946.
  Results indicated that at age 11, children who later
  developed schizophrenia showed a significant excess
  of mixed-eye dominance as compared to the remainder
  of the cohort. The authors failed, however, to
  detect a significant difference in hand preference
  between children who later developed schizophrenia
  and children who did not. Nevertheless, Cannon et al.
  interpreted their eye dominance findings as an indication
  that lateralization might play a role in the
  pathogenesis of schizophrenia.

And in the genomic age, some genetic candidates correlating with both lateralization and some mental illnesses have been identified...

  Common polymorphisms in the gene PCSK6, whose protein product mediates the development of brain and body asymmetry through the NODAL pathway, have recently been associated with handedness in three studies, making it a key candidate gene for understanding the developmental and expression of human lateralization. We tested the hypothesis that the PCSK6 VNTR polymorphism rs1053972 influences the expression of handedness and aspects of dimensional schizotypy and autism. For a sample of 709 healthy individuals, rs1053972 genotype was significantly associated with categorical measures of handedness, and with dimensional handedness in subsets of the population with high schizotypy and magical ideation or a lack of strong right-handedness. Both findings showed evidence of stronger or exclusive effects among females, compared to males. Genotypes of PCSK6 also showed significant sex-limited associations with magical ideation, a component of positive schizotypal cognition measured using the Schizotypal Personality Questionnaire, and total autism score, measured using the Autism Spectrum Quotient. These results partially replicate previous studies on effects of PCSK6 rs1053972 genetic variation on handedness phenotypes, link the PCSK6 gene with the dimensional expression of neurodevelopmental conditions in healthy individuals, and show that associations of this gene with handedness and psychological phenotypes exhibit evidence of sex-limited effects.

Although the mechanisms by which PCSK6 causes lateralization are somewhat understood, the paper says nothing about how it might cause any of the mental illnesses mentioned. So it looks like researchers don't have any clue beyond the observation that [lack of] lateralization is a risk factor for mental illness... except for...

One theory that's been advanced (prior to any genomic knowledge):

  T. J. Crow suggested that the genetic variance associated with the evolution in Homo sapiens of hemispheric dominance for language carries with it the hazard of the symptoms of schizophrenia. Individuals lacking the typical left hemisphere advantage for language, in particular for phonological components, would be at increased risk of the typical symptoms such as auditory hallucinations and delusions.

And a 2009 paper that has Crow among its authors claims to

  show for the first time how the deficit of lateralization in the schizophrenic brain is specific for the phonological component of language. This loss of hemispheric dominance would explain typical symptoms, e.g. when an individual's own thoughts are perceived as an external intruding voice. The change can be interpreted as a consequence of “hemispheric indecision”, a failure to segregate phonological engrams in one hemisphere.

This study wasn't cited much, so I'm not sure how conclusive its evidence was considered by others.

A year later, a paper (in a more prestigous journal) concluded:

  As language lateralization was not significantly reduced in the non-psychotic individuals with auditory verbal hallucinations, a direct relationship between auditory verbal hallucinations and decreased language lateralization can not be established at present.


How successful is hypnosis or hypnotherapy over a distance, for example, over Skype? Some hypnotherapists offer healings over the internet, whereas some other don't. I'd like to know how successful is hypnosis or hypnotherapy over a distance, for example, over Skype?

A literature review was conducted Barak et al. (2008) that compared the effectiveness of internet-based psychotherapy in general (not specifically hypnosis). From their abstract, the results indicate that:

  The overall mean weighted effect size was found to be 0.53 (medium effect),
  which is quite similar to the average effect size of traditional, face-to-face
  therapy.

Following, they

  [...] examined interacting effects of various possible relevant moderators of the effects of online therapy, including type of therapy [...], type of outcome measure, time of measurement of outcome (post-therapy or follow-up), type of problem treated, therapeutic approach, and communication modality,
  among others. A comparison between face-to-face and Internet intervention
  as reported on in 14 of the studies revealed no differences in
  effectiveness.

In short, the studies reviewed,

  provide strong support for the adoption of online psychological
  interventions as a legitimate therapeutic activity [...].


Are the language and sound centres of the brain in the same area? I am an English major currently taking a Psycholinguistics module. One of the things we learned is that speech perception is handled differently from non-speech sound perception. Our brain is trained to break down speech signals more intricately than non-speech information, which is why we are able to distinguish syllable and word boundaries.

Since speech sounds are perceived differently than general sounds, my question is this: do different areas of the brain light up when speech is perceived as opposed to a general sound?

I've spent a few hours Googling this, but I found no answers. The only thing I found is that a particular section of the temporal lobe is responsible for auditory perception.

I would expect that a general sound activates mainly the temporal lobe while hearing speech would activate the temporal lobe and areas of the brain associated with the words currently in the content of the speech.

Short answer
The primary auditory cortex is mainly involved in relatively simple processing of sound. The language areas involved in producing and understanding speech are associative auditory cortices and are considered to be areas higher up in the hierarchy. They are connected to the primary auditory cortex, but are situated at anatomically different locations in the brain.

Background
The primary auditory cortex is engaged in the low-level processing of sound. For example, it contains a tonotopic map that is used to separately process the various frequencies in the incoming sound (Purves et al., 2001) (Fig. 1).

The language area involved in production of speech of the brain is called Broca's area (Fig. 1) and is anatomically distinct from the primary auditory cortex.

The part of the brain dealing with understanding speech is Wernicke's area (Fig. 1), and is also a distinct anatomical structure in the brain.

The angular gyrus has also been associated with specific speech production pathologies (Fig. 1).

Fig. 1. Central auditory system. source: McGill University

Reference
- Purves et al. (eds). Neuroscience, 2nd ed. (2001). Sunderland (MA): Sinauer Associates


Why Is It That We Have Blindspots in Our Eyes? Introduction:

We humans have an eye resolution of about $576$ megapixels, but just like how nothing is perfect, our eyes have blindspots where we can't sense any information.

In fact, you can find your blindspot by covering one eye, focusing on an object in front of you, set your thumb out in front and translate it until you can't see it.

  Questions:

Why do our eyes have blindspots?
If we have blindspots, why do we still sense information in that area?

What I mean for $2$ is that even though we have blindspots, we are still able to pick up information (put in simpler terms, why is our vision perfectly smooth instead of riddled with "dark" holes where we can't see anything).

This has baffled me for some time. Any ideas?

The blind spots are scotomas (areas of degenerated acuity) found in all mammalian eyes, and are due to the way the optic nerve crosses the retina (back of the eye):

  Because there are no cells to detect light on the optic disc, the
  corresponding part of the field of vision is invisible. Some process
  in our brains interpolates the blind spot based on surrounding detail
  and information from the other eye, so we do not normally perceive the
  blind spot.

Scotomas can result from eye damage as well, and the result is the same:

  There is no direct conscious awareness of visual scotomas. They are
  simply regions of reduced information within the visual field. Rather
  than recognizing an incomplete image, patients with scotomas report
  that things "disappear" on them.

As photoreceptor density in our eyes is not evenly distributed, and changes over time due to ageing and cell damage, the way our brain processes the visual field is probably an adaptation, so it is not useful to think of it as "pixelated":

  In vision, filling-in phenomena are those responsible for the
  completion of missing information across the physiological blind spot,
  and across natural and artificial scotomata. There is also evidence
  for similar mechanisms of completion in normal visual analysis.

There are three main perspectives on how this happens in the brain.  The first is "bottom-up" - called isomorphic filling-in - which is done by early visual systems using information from neighbouring areas.  Think of this like the "magic healing brush" in Photoshop.  The second is "top-down" - called symbolic filling-in - which is done by downstream areas of the brain filling in the missing parts with higher-level knowledge.  The third is that filling-in is a fallacy called the homunculus argument, that is based on the false notion of a Cartesian theatre - that the visual system "projects" an image from the eye onto an observer inside our brain.  However this does not make any sense, and so there is no reason to suppose that any kind of "filling-in" process actually needs to happen.

PS: The eye holds an interesting place in the history of evolution, as it has been used to support the case for both intelligent design - due to its amazing complexity - and evolution by chance - due to its flawed design.  In mammalian eyes, the optic nerve delivers neurons to photoreceptors from in front, requiring it to pass through the retina.  In cephalopod (eg, octopus) eyes, the optic nerve delivers neurons to photoreceptors from behind - a design that results in no blind spots.


What is the difference between a psychopath and sociopath? The Internet is of course full of memes from Sherlock Holmes show, based on one of the episodes having Sherlock self-diagnose:

  I'm not a psychopath, I'm a highly functioning sociopath

But what exactly is the difference?

Wikipedia does not actually seem to offer any meaningful distinction between the two, including seemingly indicating that they are synonymous in DSM but not actually named there.

  The DSM and International Classification of Diseases (ICD) subsequently introduced the diagnoses of antisocial personality disorder (ASPD) and dissocial personality disorder, stating that these have been referred to (or include what is referred to) as psychopathy or sociopathy.

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.


What's the difference between inductive and deductive research in cog sci? I'm not really clear on what the implications are for inductive vs deductive research methodology and analysis. Any examples or input would be great!

As far as my knowledge goes, I don't think these two types of reasoning in cogsci are any different to other forms of inductive or deductive reasoning: one is a bottom-up approach and the other a top-down process.

Deductive reasoning starts at the general and moves towards the specific, going from theory to hypothesis, observation to a confirmation. This is good science: a priori we form specific predictions and test them in very restrictive lab settings. An example could be examining modular and embodied approaches to cognition, forming a specific hypothesis about a specific circumstance, and then testing it.

Inductive reasoning on the other hand works visa-versa, going from an observation to a pattern, a tentative hypothesis to a theory. This is not always a good way to work, especially for quantitative methods, as it relies upon post hoc interpretations of observed effects. Work of this form could be interested in understanding stress in the workplace, may interview people about it and then finally form a conclusion based upon these conversations.

The latter is more useful to qualitative research, the former is practically necessary for quantitative work.


Is there anything called Genetic Anxiety? We inherit a lot from our ancestors, but how much the term Genetic Anxiety is true, and if it is true, can it be cured through the same ways(CBT, Exposure Therapy) or it has to be dealt with medications? Put otherwise, is it the medications only that can cure genetic anxiety?

Predisposition to anxiety can be inherited:

  Genetics and family history (e.g., parental anxiety) may predispose an
  individual for an increased risk of an anxiety disorder, but generally
  external stimuli will trigger its onset or exacerbation. Genetics
  accounts for about 43% variance in panic disorder and 28% in
  generalized anxiety disorder.

Treatment for anxiety disorders is not generally modified for genetic component, so therapies such as conditioning or CBT may be used regardless.  All anxiety disorders are assumed to involve an environment (non-genetic) trigger that can be addressed through therapy.

Research by Dias & Ressler (2013) suggests that this is not necessarily the case in mice, where epigenetics alone (with no environmental trigger) can cause a purely genetic anxiety.  (Layman version)


What are the internal and external variables for varying levels of self-awareness? I'm looking for references to studies that show which variables increase or decrease self-awareness and to what degree.

For example, internal variables could be level of a certain vitamin, brain chemical, oxygen level, form of spine, etc. and/or external variables like emotional trauma, meditation, altitude, contact with water, etc.

This is just a sketch of an answer.
It is important to clarify how we define "self-awareness".

The self: There is a huge social psychological literature on the self.
For a scientific review, see for example Ellemers et al (2002).
Even the concept of self-awareness is contentious in that it posits that there is a self to be discovered whereas I assume most researchers would acknowledge that the self is at least partially a social construction.

Psychological well-being: A sense of self-awareness also relates to many other constructs such as having a sense of life purpose or meaning. For more information on that you could look at the psychological well-being literature. At the risk of self-promotion, I can point you to Grant et al (2009) where we reported some of Big 5 correlates of psychological well-being where for example we showed that self-reported purpose in life (i.e., a little bit like self-awareness)  correlated well with high extraversion (r=.33), high conscientiousness (r=.45) and low neuroticism (r = -.44).

Self-efficacy: An alternative perspective would be to look at self-efficacy research. Such research often looks at the relationship between a person's predicted and actual performance. Such research often shows that specific performance feedback with practice is important in generating accurate self-beliefs about one's own competence.

Self-other correlations: I imagine also that there is literature that looks at self-other correlations for various characteristics. It would be interesting to see what predicts the size of self-other discrepancies in such domains as personality, and performance. Unfortunately, I don't have any particular references on hand.

References

Ellemers, N., Spears, R., & Doosje, B. (2002). Self and Social Identity*. Annual review of psychology, 53(1), 161-186. PDF
Grant, S., Langan-Fox, J., & Anglim, J. (2009). Big Five Traits as predictors of subjective and psychological well-being. Psychological Reports, 105, 201-231. PDF


What does fMRI measure exactly It is true that blood flows to wherever the brain is most activated and does fMRI measure the blood flow inside of the brain through oxygen content?

As a slight modification of your statement: blood flow increases wherever activity in the brain increases.

The type of fMRI that uses this principle is blood-oxygenation-level-dependent fMRI or  BOLD fMRI. MRI in general detects signals by picking up proton signals from water molecules. This proton signal is basically caused by magnetizing the protons causing their spin to change. A subsequent powerful radiowave disrupts this spin and the following relaxation phase of the protons to the original state can be detected by MRI. Water, and hence protons are everywhere in the body, including the brain and the blood. Deoxygenated hemoglobin (hemoglobin without oxygen) in blood changes the proton signal in its immediate surroundings due to the magnetic properties of deoxyhemoglobin. This is caused by the fact that deoxygenated hemoglobin is paramagnetic and decreases the signal that protons release. In fact, it has been regarded as noise in structural MRI scans. Oxygenated hemoglobin does not have this property.
Radiopaedia has a nice explanation as to exactly how the BOLD signal is used in BOLD fMRI, and I quote:

  When a specific region of the cortex increases its activity in response to a task, the extraction fraction of oxygen from the local capillaries leads to an initial drop in oxygenated haemoglobin [...]. Following a lag of 2-6 seconds, cerebral blood flow (CBF) increases, delivering a surplus of oxygenated haemoglobin, washing away deoxyhemoglobin. It is this large rebound in local tissue oxygenation which is imaged.

So to sum up: brain activity increases the BOLD signal by picking up oxygen-changes after an increased blood flow to that specific part of the brain. So your statement that fMRI measures blood flow is technically incorrect. Doppler techniques can be used to measure the actual flow of blood.


how to train our brain to always use left part for thinking & deciding things? how to train our brain to always use left part for thinking & deciding things?
How do I not take emotional decisions

Unfortunately this question is based on a false premise. Thanks for asking. The oversimplified view on brain lateralisation is so stubbornly persistant and it invaded so many meditation guides, self help blogs, pseudoscientific faith healing and even job interviewer criteria, that it is now a part of "viral" phenomenon.

Yes, brain lateralisation exists. But it does not work in the oversimplified way they describe.

Interestingly, M. Gazzaniga shown sometimes the "random versus linear" relation work in sort of [opposite][1] way than the popular myth.

  Writing an overview of the split-brain research in a 2002 article for Scientific American, Gazzaniga concluded, based on the interpreter phenomenon and other findings, that the left hemisphere is “inventive and interpreting,” whilst the right brain is “truthful and literal.” This seems at odds with the myth invoked by Rabbi Sacks and many others.

[1][https://www.psychologytoday.com/intl/blog/brain-myths/201206/why-the-left-brain-right-brain-myth-will-probably-never-die]


Does neuroticism cause people to hurt others? Is neuroticism related to harming others? Is neuroticism related to increased criminal behaviour?
And in this case, would it be useful to coach / help a neurotic person through psychotherapy?

I've edited your question somewhat; I hope I preserved its meaning.

Neuroticism relates to personal discomfort largely by definition, and probably to uncomfortable social interaction as well, though somewhat less by definition. Consider this hypothetical, mediated pathway:

Neuroticism $\rightarrow$ Anxiety $\rightarrow$ Social anxiety $\rightarrow$ Personal social discomfort $\rightarrow$ Others' discomfort

The first three of these paths are almost definitional; the last only assumes that people ordinarily feel more comfortable when interacting with others who are comfortable. Each step from neuroticism to others' discomfort changes the construct slightly, so the relationship attenuates across each step to whatever extent these mediators are all necessary, but I suspect the relationship is still reasonably strong from one end to the other. For a bit of empirical support (indirect – best I could find quickly), note that marriage satisfaction relates negatively to the neuroticism of one's partner (Fisher & McNulty, 2008), though this may be less true of women with neurotic husbands (Whiteford, 2010; for other moderators, see Larson, Blick, Jackson, & Holman, 2010).

The relationship between neuroticism and crime is somewhat more complex, largely because crime itself is diverse. Incarcerated populations are more neurotic (Dang & Sharma, 1995; Singh, Singh, Sinha, & Kumari, 1985; Eysenck & Eysenck, 1971; I also found support for this via negative emotionality in my own work as a research assistant in Robert Krueger's lab at the University of Minnesota in 2005), but neuroticism may not be the best trait predictor of delinquency (self-reported; Furnham & Thompson, 1991), antisocial behavior, or aggression – agreeableness seems to relate more strongly (negatively; Jones, Miller, & Lynam, 2011). Neuroticism relates to these, and to substance abuse and antisocial personality disorder, but not as strongly as to agreeableness or conscientiousness (both negative correlates; Ruiz, Pincus, & Schinka, 2008; see also Walters, 2014). Neuroticism doesn't predict criminal recidivism very well compared to demographic factors either (Gendreau, Little, & Goggin, 1996).

As @what implied in his response to your other question, "Would most people benefit from psychotherapy?" it seems safe enough to assume that anyone could benefit from psychotherapy, criminals included. Neuroticism is often undesirable from a personal standpoint, so neurotic individuals per se might be fairly motivated therapy clients, whereas antisocial personality disorder (ASPD) is more ego-syntonic. ASPD is notoriously difficult to treat, though this reputation may be debatable. Wikipedia:

  ASPD is considered to be among the most difficult personality disorders to treat [(Gabbard & Gunderson, 2000)][verification needed]. Because of their very low or absent capacity for remorse, individuals with ASPD often lack sufficient motivation and fail to see the costs associated with antisocial acts...They may only simulate remorse rather than truly commit to change: they can be seductively charming and dishonest, and may manipulate staff and fellow patients during treatment [(Oldham, Skodol, & Bender, 2005)][verification needed]. Studies have shown that outpatient therapy is not likely to be successful, however the extent to which persons with ASPD are entirely unresponsive to treatment may have been exaggerated [(Salekin, 2002)].

  Those with ASPD may stay in treatment only as required by an external source, such as a parole. Residential programs that provide a carefully controlled environment of structure and supervision along with peer confrontation have been recommended [(Gabbard & Gunderson, 2000)]. There has been some research on the treatment of ASPD that indicated positive results for therapeutic interventions [(Derefinko & Widiger, 2008)]. Schema Therapy is also being investigated as a treatment for ASPD [(Bernstein, Arntz, & Vos, 2007)]. A review by Charles M. Borduin features the strong influence of Multisystemic therapy (MST) that could potentially improve this imperative issue. However this treatment requires complete cooperation and participation of all family members [(Gatzke & Raine, 2000)]...

  Therapists of individuals with ASPD may have considerable negative feelings toward clients with extensive histories of aggressive, exploitative, and abusive behaviors [(Gabbard & Gunderson, 2000)]. Rather than attempt to develop a sense of conscience in these individuals, therapeutic techniques should be focused on rational and utilitarian arguments against repeating past mistakes. These approaches would focus on the tangible, material value of prosocial behavior [(Beck, Freeman, & Davis, 2006); emphasis added].

An interesting interaction may occur between ASPD and neuroticism (via depression, a correlated emotional state) in predicting psychotherapeutic outcomes for substance abuse: patients with both ASPD and depression respond better than those with ASPD only (Gabbard, 2000). This further supports a mediated link between neuroticism and criminality:

Neuroticism $\rightarrow$ Substance abuse $\rightarrow$ Criminality

Neuroticism $\rightarrow$ Depression $\rightarrow$ Better outcomes for psychotherapy of substance abuse, given ASPD $\rightarrow$ Less recidivism? Worth testing at least!

References

- Beck, A. T., Freeman, A., & Davis, D. D. (2006). Cognitive therapy of Personality Disorders (2nd Ed.). Guilford Press.
- Bernstein, D. P., Arntz, A., & Vos, M. D. (2007). Schema focused therapy in forensic settings: Theoretical model and recommendations for best clinical practice. International Journal of Forensic Mental Health, 6(2), 169–183. Retrieved from http://www.schematherapytraining.com/storage/Bernstein.pdf.
- Dang, R., & Sharma, M. (1995). Study of neuroticism and socio-demographic factors amongst female undertrials. Indian Journal of Criminology, 23(2), 65–70.
- Derefinko, K. J., & Widiger, T. A. (2008). Antisocial personality disorder. In S. H. Fatemi & P. J. Clayton (Eds.), The Medical Basis of Psychiatry (pp. 213–226). Totowa, NJ: Humana Press.
- Eysenck, S. B., & Eysenck, H. J. (1971). A comparative study of criminals and matched controls on three dimensions of personality. British Journal of Social and Clinical Psychology, 10(4), 362–366.
- Fisher, T. D., & McNulty, J. K. (2008). Neuroticism and marital satisfaction: The mediating role played by the sexual relationship. Journal of Family Psychology, 22(1), 112–122. Retrieved from http://www.recoveryonpurpose.com/upload/Neuroticism%20and%20Marital%20Satisfaction.pdf.
- Furnham, A., & Thompson, J. (1991). Personality and self-reported delinquency. Personality and Individual Differences, 12(6), 585–593.
- Gatzke, L. M., & Raine, A. (2000). Treatment and prevention implications of antisocial personality disorder. Current Psychiatry Reports, 2(1), 51–55.
- Gabbard, G. O. (2000). Psychotherapy of personality disorders. Journal of Psychotherapy Practice and Research, 9(1), 1–6. Retrieved from http://vuir.vu.edu.au/19368/27/00jpr001.pdf.
- Gunderson, J. G., & Gabbard, G. O. (Eds.). (2008). Psychotherapy for personality disorders (Vol. 13). American Psychiatric Publishing.
- Gendreau, P., Little, T., & Goggin, C. (1996). A meta-analysis of the predictors of adult offender recidivism: What works! Criminology, 34(4), 575–608.
- Jones, S. E., Miller, J. D., & Lynam, D. R. (2011). Personality, antisocial behavior, and aggression: A meta-analytic review. Journal of Criminal Justice, 39(4), 329–337.
- Larson, J. H., Blick, R. W., Jackson, J. B., & Holman, T. B. (2010). Partner traits that predict relationship satisfaction for neurotic individuals in premarital relationships. Journal of Sex & Marital Therapy, 36(5), 430–444.
- Oldham, J. M., Skodol, A. E., & Bender, D. S. (Eds.). (2007). The American Psychiatric Publishing textbook of personality disorders. American Psychiatric Publishing.
- Ruiz, M. A., Pincus, A. L., & Schinka, J. A. (2008). Externalizing pathology and the five-factor model: A meta-analysis of personality traits associated with antisocial personality disorder, substance use disorder, and their co-occurrence. Journal of Personality Disorders, 22(4), 365–388.
- Salekin, R. T. (2002). Psychopathy and therapeutic pessimism: Clinical lore or clinical reality? Clinical Psychology Review, 22(1), 79–112. Retrieved from http://www.researchgate.net/publication/11564340_Psychopathy_and_therapeutic_pessimism._Clinical_lore_or_clinical_reality/file/60b7d5162d67bf28b8.pdf.
- Singh, U. P., Singh, L. B., Sinha, B., & Kumari, R. (1985). Extraversion, neuroticism and criminality: A comparative study of different criminal groups. Indian Journal of Social Work, 46(2), 259–266.
- Stone, M. H. (1993). Abnormalities of personality: Within and beyond the realm of treatment. WW Norton & Co.
- Walters, G. D. (2014). Drugs, crime, and their relationships: Theory, research, practice, and policy. Jones & Bartlett Publishers.
- Whiteford, N. R. T. (2010). Neuroticism, marital interaction, and relationship satisfaction: An exploration of affect mediation. (Doctoral dissertation, University of Colorado at Boulder).


Reliable channel or method for self-study of Psychology Out of interest, I've been reading some psychology topics online recently (I have zero background in psychology). For example, Maslow theory in depth. On and off, I come across terms that sound like having same meaning. So I need to search their explanation, in order to learn their differences, if any. More and more often, I run into situation where different psychology related websites giving slightly different explanation, or sometimes, even conflicting explanation. So, I'm often confused and unable to determine which explanation is the right one.

Is there a de-facto reliable source to learn psychology (except attending school), where knowledge and explanation given are considered as truth? Or... is the field of Psychology itself still full of ambiguity nowadays?

--- update 4/19 (summary)

My study approach is by keep searching and reading from multiple websites until I reach a point where I feel somewhat confident to take a guess. All along I've been uncomfortable with this approach because I find it not as productive as I wish, and the outcome may not reflect the truth.

My understanding from input of @AliceD and @Chris Rogers is that, it seems that to learn psychology in informal way for non-pro purpose (in my case, for personal growth, to understand myself better), this is the logical and viable way, even though it is not as intuitive as I've been hoping. And for those who suspect they have mental health problem, the best is to reach out to registered mental health professional for help.

Psychology can be said to be an empirical science which is built up out of the elements of experience (Avelin, 1933).

Assuming Psychology in general is empirical, its principles can be investigated by experiments, e.g., through the gold standard of clinical research, namely randomized controlled clinical trials (RCTs). Such studies are generally considered to be reliable, yet they are not always accurate, as they are still prone to all sorts of troubles, to name a few see Fig. 1.

All these potential sources of error can lead to false conclusions and hence different studies may yield conflicting evidence. As such, the 'truth' may be out there, but often it is represented in the scientific community by consensus, rather than fact. Different people may adhere to different beliefs, and rely their views on a select number of results, rather than the consensus. As such, even reputable textbooks may convey a biased message.

To search for the book of truth, as you seem to do, is in vain. It hasn't existed, does not exist, and will not exist. In fact, the best sources are meta-studies that compare the available data critically and come to a consensus, rather then stating them as facts.

Fig. 1. source: Sessley & Imrey (2015)

References
- Avelin, Nature (1933); 132: 841–3
- Sessley & Imrey, Anesthesia-analgesia (2015); 121(4): 134-42


Does verified evidence for Freudian repression of traumatic memories exist? This is sort of related to this other question, except that here I am not asking whether the brain is viewed as being capable of repressing memories, but about any verified cases of where that has happened.

I was watching a documentary in which a psychiatrist said that an individual always remembers traumatic events, and that there is no evidence for the Freudian notion that the brain represses traumatic memories.

So here I specifically want to exclude as evidence solely from claims from people who say that they were abused as children but suppressed these memories (and consequently either did, or did not, develop multiple personalities).

What I am interested in is verified evidence of cases where a person suffered trauma but the memories of the trauma were repressed as per the Freudian notion. With this I mean that I also want to exclude cases where the individual learned to live with the past and consequently memories of the trauma faded because it no longer carried any emotional significance to the person.

I would appreciate references to academic literature or articles where the evidence is mentioned.

Does verified evidence for Freudian repression of traumatic memories exist?

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

Short answer

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

Long answer

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

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

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

REFERENCES

Neurobiology of Repression

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


Is self-infallibility a mental disorder? I realize all people have various and complex biases, and that we all get into arguments from time to time. However, I've known one or two people who seemed abnormally resistant to suggestions that they might be mistaken. Their tendancy to distrust and argue seemed to impair them socially, to the point where they struggled to maintain relationships. This makes me wonder if "self-infallability" is ever actually a mental disorder.

Is there a mental disorder associated with being severely argumentative or otherwise "self-infallible"? Especially if it impairs one's social or academic skills?

I've not seen self-infallibility listed anywhere; however, there are a few psychological constructs that may be useful:

Dark Triad
DSM5 - Conduct Disorder
DSM5 - Narcissistic Personality Disorder
DSM5 - Antisocial Personality Disorder

Overconfidence may be a synonym for self-infallibility in the context you are thinking.  Overconfidence would normally be thought of as a component of narcissism.
More information would probably be required to distinguish between the four identified psychological constructs but hopefully these four links are a starting point for further research.
References
Jones, D. N., & Paulhus, D. L. (2014). Introducing the Short Dark Triad (SD3): A Brief Measure of Dark Personality Traits. Assessment, 21(1), 28–41. https://doi.org/10.1177/1073191113514105


Term for Sudden Change in Beliefs I'm familiar with terms and concepts like cognitive dissonance, confirmation bias, conformism and belief systems (a political term).

I'd like to learn more about what some might call an "awakening." For example, imagine a person going through life only vaguely aware of things like "Big Brother," government corruption and conspiracy. Suddenly, an event(s) or observation(s) triggers a realization that at least some of these rumors are true.

This person finds himself desperately searching for answers while simultaneously struggling with the need to cling to cherished beliefs.

Do psychologists have a term for such an awakening and/or the ensuing trauma that can accompany it?

It would be especially helpful if you could mention any psychologists who have studied it, books written about it, etc.

"Sudden conversion" probably covers at least a subset of what you seem to have in mind. Sudden conversion has been studied in the psychology of religion, as early as psychology has been around basically; I found an article (which is reviewing a book of Morton Prince on the topic) published in Psychological Bulletin in 1907.


Is a more specific breathing technique better than just slow, deep breathing for calming oneself? We're told by a Big Think Mind Hack video (carried by some tabloids) that 1:2 inhale:exhale breathing technique is better than just slow, deep breathing for calming yourself. Is there systematic empirical evidence that one technique of slow/deep breathing (this 1:2 one or another) is superior to just less specific ways of slow/deep breathing for dealing with panic attacks or lesser versions thereof or more generally calming oneself?

Any anxiety — and especially with Panic Attacks — can often but not always lead to Hyperventilation.  Steady, slow breathing will prevent it, whilst also helping to relieve the anxiety.

Whilst looking into the answer to your question, there are a few resources out there discussing the best techniques for dealing with hyperventilation.

MedlinePlus.gov mentions that hyperventilation creates a low level of carbon dioxide in your blood.

The low levels of Carbon Dioxide is the basis of the paper bag technique which you may have heard about.

It is the traditional practice to treat acute hyperventilation (thought to be due to anxiety) by having patients rebreathe the carbon dioxide using a brown paper bag.  However, there are reports that there are cases in which this treatment, incorrectly applied to patients who were hypoxemic or had myocardial ischemia, resulted in death. (Callaham, 1989)

This will be the reason why WebMD states, although the technique is useful, that you must not use a paper bag if:

  You have any heart or lung problems, such as coronary artery disease, asthma, chronic obstructive pulmonary disease (COPD, emphysema), or a history of deep vein thrombosis, stroke, or pulmonary embolism.

or if you are at a high altitude [above 6000 ft (1829 m)].

Interestingly, MedlinePlus states in the same article linked above that the heart or lung problems mentioned by WebMD can be medical causes of hyperventilation and

  Emotional causes include:

  Anxiety and nervousness
  Panic attack
  Situations where there is a psychological advantage in having a sudden, dramatic illness (for example, somatization disorder)
  Stress

WebMD in another article states that breathing exercises help to deal with hyperventilation and suggests to

  Breathe through pursed lips, as if you are whistling, or pinch one nostril and breathe through your nose. It is harder to hyperventilate when you breathe through your nose or pursed lips, because you can't move as much air.
  Slow your breathing to 1 breath every 5 seconds, or slow enough that symptoms gradually go away.

MedlinePlus.gov also has a detailed explanation of Pursed Lip Breathing.

As for studies on effective long term treatments, Alicia Meuret of Southern Methodist University in Dallas led a study pitting Cognitive Therapy against CART (Capnometry-Assisted Respiratory Training).  After some searching, I found the Meuret's manuscript on the National Institutes of Health website (Meuret, et al. 2010)

Apparently, according to the LiveScience article linked above, Meuret said,

  Panicking people are often told to calm down and "take a deep breath," Meuret said. But for someone hyperventilating during a panic attack, deep breathing is a bad idea. That's because hyperventilation happens when people breathe so quickly and deeply that they expel an unusually high amount of carbon dioxide, which in turn causes symptoms like dizziness and numbness. Those symptoms tend to make people feel like they're suffocating, so they breathe quicker and deeper, further exacerbating the problem.

CART, was developed to systematically change hypocapnia in patients with Panic Disorder through a brief, tightly controlled 4-week training program that uses immediate feedback via a portable capnometer.  Here is a video showing the capnometer in use.

References

Callaham, M. (1989) Hypoxic hazards of traditional paper bag rebreathing in hyperventilating patients Annals of Emergency Medicine 18(6): pp. 622—628
PMID: 2499228 DOI: 10.1016/S0196-0644(89)80515-3

Meuret, A. E., Rosenfield, D., Seidel, A., Bhaskara, L. and Hofmann, S. G. (2010) Respiratory and Cognitive Mediators of Treatment Change in Panic Disorder: Evidence for Intervention Specificity Journal of Consulting and Clinical Psychology, 78(5): pp. 691—704
PMCID: PMC3327286 DOI: 10.1037/a0019552


Brain-computer interface with EEG: how to name imaginary movement of a non-self object? I am working on Brain-Computer interfaces. In my project we try to control the movement of a robot in three directions, namely forward, right and left.

We have done an EEG experiment where we have asked subjects to imagine the movement of this robot to the wanted direction. For example, if the subject wanted to move the robot forward, he needed to imagine the robot was moving forward.

Is this type a motor imagery experiment? If not, what would the scientific word be that describes this type of experiment?

As far as I know, brain-computer interfaces based on EEG use motor-cortex responses by asking the subject to imagine body movements. E.g., a left-arm movement imagination would translate to moving the robot to the left etc. In other words, imagining the robot going left will probably result in a diffuse, poor-defined brain response, while imagined motor movements are more useful. See a slide presentation here on this topic.


What is the difference between "target" and "foil" in experimental design? What is the difference between

  "target"

and

  "foil"

in experimental design in psychology?  And how is a foil different from a distractor?

A target is:

  A stimulus that a research participant or subject is searching for or
  trying to concentrate on, and that in research is often accompanied by
  distractors.

And a foil is:

  In research methodology, another name for a distractor.

For example, in a multiple choice question, the correct answer is the "target", and the rest are "foils" or distractors.  This is similar to a police lineup, where the suspect is the "target", and the rest are "foils" or fillers.  "Foil" and "distractor" are synonyms.


Why does even the most rational brain forget logic in a dream? Scenario 1) Now we all know gravity is real. Yet when we dream that we are flying we forget/or are oblivious to the entire concept of gravity as if you have never experienced gravity.

Scenario 2) When dreaming of a deceased relative long or recent sometimes the dream is in their lifetimes and during the dream the brain has no recollection of the event of their death.

In both these scenarios you can control the dream for example if you are flying you can change directions or set the scenery and are aware you are dreaming but the things you are unaware of are GRAVITY AND DEATH. And as soon as you wake up or figure out the reality you become awake. So my question is why does a brain forget reality/logic in a dream?

Neither rational nor logical

"...there is overwhelming evidence that Humans cannot be [rational]" - Daniel Kahneman (Thinking Fast and Slow).

To begin with, the brain is neither rational nor logical as you may think (to a large extent it is little rational and its logic is completely fuzzy). A perfectly rational and logical organ would not be able to keep us alive (such an organ could take 4 hours to choose between two bottles of wine).
So I assume that your question is more like:

How comes dreams often involve augmented reality?

On augmented realities
Try this: shut your eyes and try to imagine your lower body replaced with that of a horse. Can you do this?

You have not done this whilst dreaming, but whilst awake and conscious.
Can you bring memories of a deceased relative whilst awake? Sure you can.
So the ability to experience augmented reality is not reserved for dreams - we can incite such reality by conscious means, certain drugs or brain damage.
Whilst you were dreaming
There are various theories on why we dream and what happens whilst we dream.
A key to many theories is random brain activity. You actually experience this whilst awake when you leave the central executive mode (stay-on-task) and enter daydreaming one - where short thoughts are following in what often seems as random.
Such random activity is fully capable of triggering augmented reality, like a half-man half-horse.
There is a higher likelihood for such augmented reality to appear in dreams, since random activity is not tamed by the stay on task mechanism.


Does the mind create the body? Everything we perceive is through the 5 senses. That means the body which is perceived through sense of feeling and seeing is also formed as an image in mind or brain?
Is it correct that it is either the mind or brain that creates the body. Or some part of brain that creates the body?
Are there any articles or research along these lines?
One more thing I want to add that everything we are seeing, including the body, all appears in a small part of brain, and then we are projecting it outside?

Q: Does the mind create the body?
A: The answer depends on what you mean by “the body”.

If “the body” in the question means “the body as we perceive it”, the answer is “yes”. And, not only is the body in this sense is created by the mind, everything else in this world, the universe, and the reality as you perceive them are also created by the mind.[1,2]

It is easy to show that “the body as we perceive it” is created by the mind (or its physical counterpart – the brain) and is not the real physical body as it exists in the physical world. One of the easiest examples to show this is the finger sausage illusion (see the figure below).

Figure. Finger Sausage Illusion. A – the fingers as appeared when looked at directly and B – the fingers as appeared when one looks at the background beyond the fingers. [3]
Although the fingers as we see in our mind change (A <-> B), depending on where we focus our sight, the physical fingers themselves cannot change abruptly by just changing the sight’s focus. This proves that the fingers as we see in our mind is not the physical fingers that exists in the physical world.

But if “the body” in the question means “the physical body as it exists in the physical world”, the answer is “no”. The evidence is obvious and abundant in everyday life: just by the wish of our mind - we cannot create a new limb or new organ for the lost one; we cannot create wings to fly, gills to breath underwater, or an organ to sense echolocation even if we want to create them; and we cannot create a duplicate of our body just in case we need a limb/organ replacement.

References

Scuola Internazionale Superiore di Studi Avanzati. How the brain constructs the world. Insights into processes underlying the integration and storage of sensory signals. ScienceDialy. February 9, 2018.

Wikipedia. Neural basis of self

Ukachoke C. 3.6. Sensory perception qualia as representations of the outside world In: The Basic Theory of the Mind. 1st ed. Bangkok, Thailand; Charansanitwong Printing Co. 2018.


Do humans really feel that a \$99 price tag is significantly lower than a \$100 one? Do humans really feel that a \$99 price tag is significantly lower than a \$100 one?

Is there a name for this phenomenon and research supporting it?

The Wikipedia page of Psychological Pricing giving this chart:

Why?

  Kaushik Basu used game theory in 1997 to argue that rational consumers value their own time and effort at calculation. Such consumers process the price from left to right and tend to mentally replace the last two digits of the price with an estimate of the mean "cent component" of all goods in the marketplace.

Also related on UX Stack Exchange: Is there any advantage in marketing my product for £99.99 instead of £100?


correction for multiple comparison over many ROIs I would like to know how to correct a p value of a stiatistic when the same test was run over multiple regions of interest. The modality is MEG.
So, I have 4 Regions Of Interests, and I ran the same cluster-based permutation test on the averaged timecourse of each ROI. I got more than 10 clusters, each with p < 0.05, but how can I get the corrected p value considering there was more than one region?

Any help will be much appreciated.

You have one p-values for each ROI timecourse (for the largest cluster) indicating whether your conditions are exchangeable. If you want to correct for the 4 ROIs you could use any adequate multiple comparison correction, from classical Bonferroni (which might be too conservative as the tests are likely not completly independent) to Benjamini-Hochberg style FDR correction (but applied to the cluster permutation test p-values).

This leaves us with the question which p-values count, one per ROI (the largest cluster, i.e. smallest p-value) or the p-values for all supra cluster-threshold clusters. I would think the former is more appropriate, as you already corrected for the multiple clusters.

That is, for the Bonferroni correction you would multiply your p-values by 4, (or identically, divide your critical alpha by 4).

This solution is incomplete, as I do not know how to get corrected p-values for the second largest cluster with FDR or Holm-Bonferroni.


How to study the effect of sustained exercise and sport on well-being? I´d like to make a little case study about the impact of including regular weight training in life. I know one man who is going to start to excercise regularly and I have an opportunity to talk with him regularly (for example every month) for about six months, maybe longer. Is there any other option of making this research than via regular interview with direct questions about his view of the impact of sports in his life (for example question: What do you think you´ve learned from training?)?
I mean - If I will watch for example self-esteem and it will grow, how can i know it grew thanks to sports and not because of any other change in his life? How to relate any watched cathegory to the regular training?

Just to give you a few ideas. The ideas are ordered from better to worse. They are also mostly ordered from serious and expensive research to less serious and cheap research.

Randomised control trial:
If you are really interested in causality, you would randomly allocate a large group of people to either and exercise or one or more control conditions (e.g., no exercise; alternative activity; etc.) . You would then use various well-validated measures to measure the dependent variable of interest. For example, if you are interested in self-esteem, then you might get self-report measures using something like the Rosenberg Self-esteem scale. An even better study would measure a range of related dependent variables (reports by others of well-being; physical health; other life outcomes of interest).

It sounds like you are interested in longitudinal trajectories of this effect, so you'd want to measure these outcome variables on multiple occasions (e.g., baseline, 1 month, 2 months, 6 months, etc.).

You'd probably also want to do some kind of intention to treat analysis. Basically, there are two questions. What is the effect of the intervention for those who actually follow the protocol, and what is the effect of the intervention for those who are assigned to it but may or may not actually engage in the exercise?

One sample longitudinal study:
A simpler design would just be the same as above but without the control group. You'd have more threats to causal inference, but nonetheless, results would still be informative to the effect of exercise on self-esteem.

Single participant longitudinal study:
It seems like this is what you are talking about. There are many issues with this design. Do the results generalise to other people? Is the increase due to other factors in the person's life? That said, if this is just for hypothesis generation or exploring the ideas, it might be interesting.

Qualitative versus quantitative measurement:
Quantitative measurement of self-esteem is generally better if you are trying to test formal hypotheses about change.
Qualitative methods (e.g., asking open ended questions) is often more useful in generating hypotheses and explanations for the obtained results. That said, much more subjectivity can enter interpretation.

As an aside, it is interesting that the vast majority of infomercials selling exercise equipment rely on the cheapest and worst design: qualitative single observation measurement (i.e., anecdotes).


Cognitive Science podcasts to follow I'm currently trying to find interesting Cognitive Science related podcasts to follow. Only one I've found is You are not so smart. Does anyone know anything else? Preferably in English.

If the question is off-topic, not constructive or opinion based, please let me know and I will delete it.

Here are the ones I know about; there's much more about neuroscience than, say, theoretical or computational cognitive science, but a lot of the neuroscience podcasts cover cognitive science indirectly or partially.

All in the Mind--it's also neuroscience and mental health stuff (a lot of mental health stuff)

Brain Science Podcast--books about and interviews with researchers in neuroscience

Neuropod--Nature's neuroscience podcast

Neuroscene--"the future of neuroscience", mostly interviews or topical explorations

Naked Neuroscience--the neuroscience offshoot of Cambridge University's Naked Scientists


Does rTMS therapy require medical licensing? In my research project, besides sound and light therapies, I would like to experiment with rTMS (repetitive transcranial magnetic stimulation) on volunteers. I wonder if this requires medical licensing?

It depends on the country, but, for most of them (incl. USA and EU), you don't need a medical license to perform biomedical research, including human experiments with TMS. However, you will need legal approval, such as certified research environment, ethics/IRB permission, etc. Also, one should delineate research and clinical trials, which are governed by a special set of rules and, most often, require medical environment.


Is workaholism similar to any addiction or are there other neurological mechanisms at play? Some people are seemingly 'addicted' to their work and by doing work itself, almost to the point of precluding all other activities and interactions (usually social).  By this question, I mean when people go beyond a 'passion' for the work, into an almost obsessive approach.  (I have met a few people like this).

Is this addiction to work similar to other addictions?  or is there something else triggering this almost obsessive work-ethic to the preclusion of almost all other activities?

I am after peer-refereed articles about any studies that have been performed on this.

This is a great question - one that resonates with me especially when reflecting on my own professional life.

My answer to your question would be both speculative and (hopefully) empirical. From personal experience, I have met people in my professional life that may exhibit 'workaholic' behaviours but it is unclear whether it is driven by fear and anxiety or behaviours aligned to values to achieve almost perfect work performance.

I would start with defining precisely what workaholism is. Spence and Robbins (1992) defines a workaholic exhibiting three specific properties:

  Highly work involved
  Compelled or driven to work because of inner pressures
  Low in enjoyment of work

If we compare those properties against an addictive disorder such as Bulimia Nervosa, some surprising similarities arise. Compensatory self-vomitting behaviours tend to be a product of overevaluation of body weight and shape (Lamparda et al., 2011). Let's assume that "inner pressures" represent an individual's need to achieve their body weight and shape. Analogously, "inner pressures" such as perfectionism and responses to fear can cause this seemingly addictive workholic behaviour. I would dare say that the cognitive processes involved between these two cases would be quite similar.

Examining workaholism from a neurological perspective, in my opinion, would mimic neurological studies on addictive disorders. However, I couldn't find much. Randles et al. (2010) make reference to neurological mechanisms in describing how perfectionism and rumination can contribute to goal-oriented behaviours.

The drive to work harder and harder is likely to be influenced by the level of perfectionism and anxiety experienced by an individual (Shafran & Mansell, 2001). Catastrophising and ruminating about work performance can theoretically compel an individual to work harder to the point of psychopathology (of course, we lack the criteria). On another note, personality traits such as narcissism would probably play a role in triggering workaholic behaviours.

References

Spence, J.T. & Robbins, A.S. (1992). Workaholism: definition, measurement, and preliminary results. Journal of Personality Assessment, 58(1), 160-178
Lamparda, A.M., Byrnea, S.M., McLeana, N. & Furslandb, A. (2011). An evaluation of the enhanced cognitive-behavioural model of bulimia nervosa. Behaviour Research and Therapy, 49, 529-535
Randles, D., Flett, G.L., Nasha, K.A., McGreggor, I.D. & Hewitt, P.L. (2010). Dimensions of perfectionism, behavioral inhibition, and rumination. Personality and Individual Differences, 49, 83-87
Shafran, R. & Mansell, W. (2001). Perfectionism and psychopathology: A review of research and treatment. Clinical Psychology Review, 21(6), 879-906.


How to quickly estimate the person's level of stress with a mobile based relaxation app? I'm writing a simple iPhone relaxation app and am thinking of a very quick test I can do to learn something about the user's level of stress, anxiety, etc. The objective is to measure how effective the app is or to adjust the length of the session.

I thought of using the following measurement process:

Ask the user to trace a line with their finger, prior to relaxation
Repeat the tracing process following relaxation
Analyze and compare results to the user's previous entry or historic entries for the same user

Does this approach have any merit or validity? What other simple and quick ways are there to gauge how relaxed or stressed the user is?

A mobile device, like iPhone has 3 axis accelerometer, gyroscope, magnetometer, and a capacitive touchscreen that does not measure the pressure of a touch.

Anxiety and stress are very available states, and since you want to know how people currently feel (rather than some more implicit construct), you probably can't do much better than just asking them. A single-item anxiety measure as suggested by mlt should work.


physical symptoms of anxiety Are all the physical symptoms of anxiety caused by adrenaline. By physical symptoms I mean the muscle tension chest tightness and high blood pressure. I guess if thats true then anxiety and anger are the same at least physiologically well are they? If not what is the chemical responsible for the physical symptoms of anxiety

Short answer

Yes, they are actually similar, and they can be thought as two extremes of the same continuum. Many studies (here's a review by Lang and McTeague)suggest that the psychophysiological reactivity in the anxiety spectrum disorder is threat-related.

Long Answer

Ohman (2009) noted how predator-prey relationship is asymmetrical because there’s a larger pressure on prey than on predators.

Failure in defense against a predator determines the end of reproductive potential of prey animals. A hunting failure does not preclude future breeding.

This simple asymmetry implies that prey animals are evolutionarily shaped to exaggerate caution and avoidance of danger and this may provide a biological foundation for human anxiety disorders. In prey-predator race, prey arms became a strong capacity to associate subtle cues (smell, sounds) to the presence of a predator before its actual appearance. Learning to identify subtle signs is likely to be an evolutionary prepared ability, in the sense that very little environmental input is required.
Therefore, from an evolutionary point of view, the organisms which learned to fear environmental threats faster had a survival and reproductive advantage.

LeDoux (2000) proposed a model according to which we have preferential pathways to encode emotional stimuli and particularly threat stimuli. The Thalamo-Amygdala pathway is a very fast road that brings the information to the amygdala (which extrapolates emotional contents from the stimuli) bypassing the cortex. It is a subcortical pathway which allows us to orient the attention toward the stimulus and to prepare our organism for responding (by sending of information from the amygdala to the brainstem which controls physiological responses).
This "quick and dirty" pathway (dirty because it brings raw information that has to be integrated with the information from the cortices)is in common for fear and anxiety.

References

Of snakes and faces: an evolutionary perspective on the psychology of fear. Ohman (2009)

The anxiety disorder spectrum Lang and McTeague (2009).

LeDoux's model


How sexual activity influences a woman's sex drive Sheila Gregoire suggests that increasing the amount of sexual activity increases a woman's sexual desire in general.
I can postulate that child bearing and raising impacts significantly upon a woman's life and that possibly, when a woman finds a mate worthwhile, it is a primitive drive to reproduce.

In  studies by Winnifred B. Cutler, it is demonstrated how, as sexual frequency declines so does sex drive, for women.

 HOW SEXUAL FREQUENCY AFFECTS
A WOMAN'S SEXUAL RESPONSIVENESS,
FERTILITY, AND HEALTH
Paul H. Byerly

Is it true that having sex increases a women's future desire to have sex?
What physiological purpose does this serve?

The inverse of your first question might hold generally true: that desired sexual frequency could influence a woman's actual sexual frequency.

Willoughby and Vitas (2012) conducted a study focusing on the sexual desired discrepancy between male and females. They make reference to sexual desire discrepancy (SDD) - difference between one's desired frequency of sexual intercourse and actual frequency of sexual intercourse.

  High SDD may then lead some females to put more resources into the
  relationship in order to work toward future sexual contact and
  increase the intimacy and closeness in their relationship. In this
  way, SDD may serve among female partners as a motivator to enhance and
  support the relationship as it progresses toward higher sexual
  frequency.

It mainly would depend on the quality and satisfaction of the sexual intercourse that would determine whether a woman's desire for greater sexual frequency would increase or not. Assuming that quality and satisfaction of sexual intercourse is high for the woman, I would say that this would increase a woman's future desire to have sex. Processes on positive expectancies give rise to higher perceived quality of the sexual relationship (McNulty & Fisher, 2008) and thus, in my opinion, if the woman expects sexual intercourse to be as good as a prior experience, they're more likely to desire it more.

So, perhaps deprivation or excess of sexual intercourse and expectancies of quality of sexual intercourse plays a major role in moulding sexual desire for women. Another thing: while the frequency of sex is predicated on the physical rewards of it for men, this may not be necessarily true for women.

References

Willoughby, B.J. & Vitas, J. (2012). Sexual desire frequency: The effect of individual differences in desired and actual sexual frequency on dating couples. Archive of Sexual Behavior, 41, 477-486.
McNulty, J.K. & Fisher, T.D. (2008). Gender differences in response to sexual expectancies and changes in sexual frequency: A short-term longitudinal study of sexual satisfaction in newly married couples. Archive of Sexual Behavior, 37, 229-240.


Predictive Experiments on Neuroscience of Free Will It seems to be very interesting that we can use modern neuroscience and cognitive science research to inform us about the ages-old question of free-will vs. determinism. The standard experiment was done by Benjamin Libet in 1983 that demonstrated that electrode activity showed that in terms of using our left or right hands - electric signals showed a significant change in activity before the reported decision to make the movement was made. This is one of the founding experiments of the neuroscience of free-will.

However, it seems that this experiment informs us in a very limited temporal duration. Since I could not find any conclusive results myself, I wanted to ask if they were any neuroscience experiments that demonstrated long-term predictive behavior. An example would be if a person with a particular imaged localized area could be said pre-hand to have a certain behavioral reactions in response to stimuli. This would defend give a strong defense to the determinist philosophical position. Of course, I'm talking about conscious reactions (such as decision-making in social situations, since the idea is that people consciously think they make their own decisions). An experiment involving unconscious processes such as memory would not be very informative.

If so:

Which experiment(s) comments on this?

What is the degree of validity of the experiment? (Summary of Methods and Results)

Are the results controversial? Does it truly make a comment on the philosophy of free will?

If not, is it that Neuroscience is still not mature enough have predictive power like hard sciences such as biology, chemistry and physics. After all, the brain is a incredibly complex organ, and responding to complex multimodal stimuli (e.g. social situations) it would further complicate the possibility of any such study.

Sources:

TIME OF CONSCIOUS INTENTION TO ACT IN RELATION TO ONSET OF CEREBRAL ACTIVITY (READINESS-POTENTIAL)
BENJAMIN LIBET, CURTIS A. GLEASON, ELWOOD W. WRIGHT, DENNIS K. PEARL
Brain Sep 1983, 106 (3) 623-642; DOI: 10.1093/brain/106.3.623

There is a good article on Wikipedia on the Neuroscience of Free Will, with far too much content to adequately summarize here.  Since your question is focused on long-term prediction of behaviour, I'll just mention about that.

Using newer fMRI technology, Soon et al (2008) used a learning algorithm to predict "free will" decisions from brain activity about 7 seconds (and up to 10 seconds) prior to the subject reporting awareness of having made the decision.  This experiment has been replicated in other labs: Presenter Marcus du Satoy undergoes it for the BBC documentary The Secret You (2009/2010), and remarks that there is something creepy about the radiologist being aware of his decision several seconds before even he is.

An important question remains regarding all long-term prediction experiments: Human behaviour is very predictable, as countless experiments in every area of psychology commonly demonstrate by manipulating causal factors - the ability to predict it well in advance with significant accuracy is hardly limited to neuroscience.  So experiments have to be very carefully designed if they are to eliminate the effects of predisposing factors such as priming in decision-making, such that decisions are not influenced by uncontrolled unconscious factors (hence truly "free will").  However, if "free will" doesn't exist, then eliminating all predisposing factors will ultimately prove futile, so until researchers can control for all variables, some doubt will always remain.

Nonetheless, research in this field has significantly changed our understanding of the role of "thought" or "will" or "volition" in the causal chain, such that they now appear to be a side-effect rather than cause of physical action.


Integrated Information Theory - If correct could humans create artificial consciousness? First off please keep in mind I am self-learning and am learning about this for fun, I have no end goal. I'm trying to make predictions about what I am learning implies or means, so I can ask better questions and clarify what I should learn/focus on learning.  I know I need to spend tons more time in understanding the physics and biology that we currently understand.  I'm looking for feedback that can help me either confirm my understanding or correct it and/or point me in directions that will help me better develop it so I can ask better questions in the future.

This assumes IIT is a valid theory.

It seems to me IIT implies that consciousness not only requires integration, but in order to achieve integration the system must be dynamic and able to respond spatially to feedback within the system. As I understand it our neurons grow and die, they can move, they receive inputs from their connections but can also be influenced by molecules that make their way to them indirectly.  There is an end result of all the behavior of the neuron and that is the movement of electrons.  The molecules and cells surrounding the neurons, provide it the ability to release the action potential. Or the stored up energy that must reach a certain threshold in order for the neuron to fire.  This firing is what must be in harmony and certain firing patterns in theory results in conscious experience.

So if humans were to artificially generate consciousness as we experience it (using non-biological methods) this would require us to develop a system that can arrange and rearrange neurons or nodes spatially that can release action potentials of electrons(not sure I'm using correct terminology/physical process) in symphony.  The neurons would need to be able to change connection weights not only through internal inputs but also through external inputs, and not only by connected nodes. We would need to understand what causes neurons to grow along particular paths or make particular connections... I assume some of this is known or theorized about.  It also seems that certain parts of neuronal intelligence is crystallized or more or less unchanging where as other parts do change and use relationships between the unchanging or slow to change parts in conjunction with more dynamic components that allow for variation in abilities to connect.

IIT seems to imply that conscious experience lies in certain configurations of the electron field (what happens beyond that is unclear) but that seems to be the end result of the actions that any particular group of neurons is taking.  I suppose not all, because it also serves the purpose of communication and coordination through out the body. It doesn't seem that synchrony in neuronal behavior coordinates chemical arrangements that would explain experience, but it does coordinate electrical fields as an end result. I'm trying to understand if that is a correct understanding whether that is one of the main outputs of neuronal firing.

IIT implies that just about everything is 'conscious' (to a degree) in that you can measure its integrated information to say how conscious it is, while accepting that what we as humans typically describe as 'consciousness' is a very high value of this measure. That's sort of the whole point of the theory: having a definition of consciousness that starts from a more basic principle ('integrated information') rather than starting at "humans are conscious" without defining what it really means to be conscious.

High levels of integrated information are not easy to achieve with typical computers we use today, but nothing about the theory says it cannot be done. If you have a sufficient level of integrated information, we can call that consciousness based on IIT.

IIT does not say anything about implementation of such a system, even though your question implies that it does (you could view this as either a weakness or a strength depending on your perspective); there are certainly ways to connect artificial systems dynamically without them needing to be neurons. It is true, however, that an individual neuron is far more complex than typical artificial instantiations of neurons, like the nodes of an artificial neural network.

As far as your paragraph beginning "IIT seems to imply that conscious experience lies in certain configurations of the electron field" I don't know what this means or where your got it; IIT doesn't say anything like this. IIT says that consciousness is what you get when you connect information to other information; for example, placing information you are measuring from the world right now in the context of your life's experience involves integrating information from your sensory systems with your memories. Computers can already achieve this to some degree, the part about human consciousness that is remarkable is just how deeply and rapidly (and automatically) these comparisons occur in parallel.

Koch, C., & Tononi, G. (2008). Can machines be conscious?. Ieee Spectrum, 45(6).


Is there any credible evidence for the theory of Spiral Dynamics? Spiral dynamics is a developmental psychology based theory that postulates these main ideas:

Organisms in the universe go through a predictable set of stages of psychological development.
These stages each exhibit a set of values that the organism tries to obtain.
Their pursuit for these values are clearly observable, i.e. it is possible to identify that the organism is trying to obtain these values.

This image illustrates the different stages postulated by the theory, the characteristics of organism's behavior that are within each level, and also their overall world view.

Here is a table (Dr. Clare Grave's model) that breaks down these characteristics into categories:

I have heard that this theory is credible and that there is evidence for it, though I have struggled to find any.

Is there any evidence that strongly suggests all living organisms/creatures/life forms, in terms of mentality, consistently travel through a set of stages, where their values (and overall objectives) are respectively: gaining assurance, obtaining survival, obtaining security, obtaining independence, and then obtaining affiliation.

While Dr. Graves himself did studies to produce this theory, his methods have been criticized heavily. At this point of time, are there any other studies that suggest that the postulate mentioned is consistent with various empirical observations?

Dr Graves' research relates to human developmental psychology, not 'all living things'. In his book Integral Psychology (2000) Ken Wilber cross references multiple bodies of work, including eastern philosophy and western psychology. Wilber mentions a number of other researchers whose work correlates with Graves' findings, including Paiget, Fowler, Kegan, Cook-Greuter to name a few.

Three key findings from Graves' work are:
1. The responsive nature of human consciousness to the complexity of life conditions.
2. The trajectory of and the human experience of change between the stages.
3. The open-ended, staged developmental sequence with alternating themes of self-expression and self-sacrifice.

You can find my interpretation of Graves' model at my website https://www.eman8.net


What is the psychological effect of wearing black clothes? Background: I read that black is usually favored by people who are dominant. I read that the black color projects dominance, and also hides the person's feelings. Police, for example, adopt black as a color.  However, I also read that black can demonstrate submissiveness. Priests wear black clothes to show submissiveness to God. In addition, sales people and business people who work with clients often wear black suits. Are they trying to appear dominant or submissive?

What is the psychology of wearing black?
Does wearing black communicate dominance or submissiveness?

This question is studied within the fields of color psychology and enclothed cognition (e.g., Adam and Galinsky, 2012), currently a hot/controversial topic in cognitive science. Without addressing the substantial questions surrounding the premises of these interpretations for situated/embodied cognition in my answer, it seems that wearing black is associated with aggressive behavior and the tendency to be perceived as more aggressive (Frank and Gilovich, 1988).

  An analysis of the penalty records of the [U.S.] National Football League and the [U.S.] National Hockey League indicate that teams with black uniforms in both sports ranked near the top of their leagues in penalties throughout the period of study. On those occasions when a team switched from nonblack to black uniforms, the switch was accompanied by an immediate increase in penalties. The results of two laboratory experiments indicate that this finding can be attributed to both social perception and self-perception processes—that is, to the biased judgments of referees and to the
  increased aggressiveness of the players themselves.

As per Artem's comment to the question, we need to be skeptical of inferring a causal relation when so many confounding factors, such as culture, could potentially be in play. A 2014 review of color psychology in the Annual Review of Psychology journal concluded that while there is mounting evidence for the influence of color on behavior, it is ultimately too early to theorize strongly on specific color psychological questions such as this (Elliot and Maier, 2014).

  The review clearly shows that color can carry important meaning and can have an important impact on people's affect, cognition, and behavior. The literature remains at a nascent stage of development, however, and we note that considerable work on boundary conditions, moderators, and real-world generalizability is needed before strong conceptual statements and recommendations for application are warranted.

References

Adam, H., & Galinsky, A. D. (2012). Enclothed cognition. Journal of Experimental Social Psychology, 48(4), 918-925.
Elliot, A. J., & Maier, M. A. (2014). Color psychology: Effects of perceiving color on psychological functioning in humans. Annual review of psychology, 65, 95-120.
Frank, M. G., & Gilovich, T. (1988). The Dark Side of Self-and Social Perception: Black Uniforms and Aggression in Professional Sports. Journal of Pereonality and Social Psychology, 54(1), 74-85.


What's the difference between a "mental disorder" and a bad personality trait? Most people are held accountable for their actions. If diagnosed with a "mental disorder" however, they are often forgiven/treated more leniently and exempted from punishment.

The same thing couldn't be said about a bad personality trait however. No one is exempted from murder for say "not being very compassionate" or "being an asshole".

Mental disorders however only seem to be a term of describe a set of bad personality traits that are displayed concurrently though. So why the special treatment?

What's the difference between a mental disorder and a bad personality trait?

I don't want to address the issue of defining mental disorders in general here, because just about any malfunctioning system in the brain can be considered a disorder. However, some disorders affect the set of processes in the brain which ultimately determine whether or not someone takes an action (the neural basis of volition, or "free will", if you will...). If these decision processes are broken, people shouldn't be held responsible for what they do, because they really have no control. So, a "mental disorder" which exempts one from responsibility can be considered one which consists of damage to the following processes:

Of course, there is the philosphical objection that mechanistic explanation (deterministic or random, doesn't matter) means nobody has free will - but the issue in society is really about free will as the ability to learn rules and follow them. A bad personality trait usually doesn't affect the above processes, and therefore doesn't impede someone's ability to make their own decisions.