Do fetuses exhibit pattern recognition in utero? I've heard that fetuses exhibit "likes", such as preferring sweeter amniotic fluid or the sound of their mother's voice. To show preference for specific voices as opposed to inborn stimuli like sweet, some form of pattern recognition would have to be involved.

By pattern recognition I simply mean exhibiting any sort of indication that by repeated exposure to a stimulus the fetus' response changes, showing that it in some way has identified the stimulus as being previously experienced.

I know of some research that indicates newborns recognize and prefer their own mother's voice but I'm not aware of specific research on children in utero.

Does any research indicate that fetuses show pattern recognition in utero, such as voice recognition? Is there an approximate time this ability presents itself?

The preference for mother's voice over a stranger's voice has been show in utero by Kisilevsky et al. (2003) by measuring the fetus' heart rate. It increased in response to mother's voice and decreased in response to a stranger's voice compared to baseline. Kisilevsky and Hains (2011) followed up the earlier study, and determined that the onset of recognition occurred at 32–34 weeks GA. Thus, at least for vocal stimuli, there is definitely some recognition from the infants. My only issue with these studies is that the mothers could hear the stimuli, thus there could be interaction from a hormonal response of the mother to her own voice and the fetus picking up on that instead of the actual auditory input.

An even more liberal reading of "recognition" as defined by the OP is possible. If we follow in the footsteps of Maturana and Varela then we should talk about the brain/mind responding not to external stimuli but to its own internal sensory world. In that case, we can consider adaptation even before sensory organs are fully developed or functional. In that case the fetus starts to adapt to senses-to-be before they develop.

Penn & Shatz (1999) showed that the connections from the eye to the visual cortex form before the retina is developed enough to respond to light. At this time the retinal ganglion cells spontaneously generate highly correlated bursts of action potentials similar to the sort of data they will generate once they actual start sensing. The preliminary bursts allow the human fetus to start developing its visual cortex before it even has functional retina. Thus, the brain of the fetus starts to learn and recognize patterns before it even has proper external sensory input.


Is there scientific evidence on the benefits of binaural beats? When two coherent sounds with nearly similar frequencies are presented to each ear respectively with stereo headphones, the brain integrates the two signals and produces a sensation of a third sound called binaural beat.

I tried to google, but a lot looks like fake evidences and not having any scientific evidences. What is the evidence for binaural beat music producing different cognitive and/or neural effects as compared to non-binaural beat music?

Since I was asked in chat about binaural beats, and have been posed this question a number of times before besides, I looked into the most recent literature using Google Scholar for the single term "binaural beats" and restricted my search to papers published between 2010-2015. For convenience, this is the definition of a binaural beat I will use.

When two coherent sounds with nearly similar frequencies are presented to each ear respectively with stereo headphones, the brain integrates the two signals and produces a sensation of a third sound called binaural beat (BB). — Gao et al., 2014.

State of the evidence
Broadly speaking, some research on binaural beats does exist, but the evidence presented in the studies I examined is by and large negative, inconclusive or statistically underpowered with respect to the efficacy of binaural beats' ability to improve cognition, and to whether it is even processed differently from acoustic beats at all.
Much of the research that does exist seems to be published in journals whose credibility I cannot vouch for, and this answer should therefore be taken for what it is: a cursory review of the best literature I could find, not as scientific fact.

Are binaural beats processed differently?

"The perceptions of binaural beats involve cortical activity that is not different than acoustic beats in distribution and in the effects of beat- and base frequency, indicating similar cortical processing."  — Pratt et al., 2010.

Do binaural beats entrain brain waves?

"We observed RP increase in theta and alpha bands and decrease in beta band during delta and alpha BB stimulations. RP decreased in beta band during theta BB, while RP decreased in theta band during beta BB. However, no clear brainwave entrainment effect was identified. Connectivity changes were detected following the variation of RP during BB stimulations. Our observation supports the hypothesis that BBs could affect functional brain connectivity, suggesting that the mechanism of BB–brain interaction is worth further study." — Gao et al., 2014.

Do binaural beats induce a frequency following effect?

"Analysis of changes in broad-band and narrow-band amplitudes, and frequency showed no effect of binaural beat frequency eliciting a frequency following effect in the EEG." — Vernon et al., 2011.

Concluding remarks
What evidence exists is mixed and, at best, inconclusive. Based on this, I will tentatively say that it appears the claims put forward by many commercial binaural beats companies, while theoretically plausible in some sense, are not empirically supported in the literature.
Therefore, the most prudent position for a consumer to adopt seems to be that binaural beat music is as preferable, but no more preferable than acoustic beat music. For researchers, of course, binaural beats remains theoretically interesting.
References

Gao, X., Cao, H., Ming, D., Qi, H., Wang, X., Wang, X., ... & Zhou, P. (2014). Analysis of EEG activity in response to binaural beats with different frequencies. International Journal of Psychophysiology, 94(3), 399-406.
Pratt, H., Starr, A., Michalewski, H. J., Dimitrijevic, A., Bleich, N., & Mittelman, N. (2010). A comparison of auditory evoked potentials to acoustic beats and to binaural beats. Hearing research, 262(1), 34-44.
Vernon, D., Peryer, G., Louch, J., & Shaw, M. (2014). Tracking EEG changes in response to alpha and beta binaural beats. International Journal of Psychophysiology, 93(1), 134-139.


What terms describe "schema" at various stages of acceptance? According to WordNet 3.0, quoted at TheFreeDictionary.com, in psychology, schema means "an internal representation of the world; an organization of concepts and actions that can be revised by new information about the world".

Within psychology, specifically as applied to learning or education, are there terms to describe schemata at different stages of acceptance, e.g.:

schema present in an individual
schema currently being added or adjusted by an individual
potential "schemata/patterns/ideas" out in the world not yet encountered by the individual

Are there specialized terms to distinguish these?

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

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

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

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


Mind uploading & its constituents: Theoretically possible? Is it possible to remove the mind from the rest of the body and have it "alive" somehow as in its former known form? Mind uploading would be computerizing a mind to preserve data, memories and etc.

There are other constituents of this though that I will outline:

1.Mind uploading as in an interlink between the mind and some proxy (may or may not be computerized, but in general it might be expected) -- i.e., having the mind function in some connective/remote form that doesn't require a body but still enables the organ to work somehow -- like if you could linke neurons/axons/synapses to some feedback system that's not body-dependent;

2.Mind drive --  the ability to store NON-computerized components of the brain in some reliable method to preserve it biological function somehow (without its native body specifically at the least). Also, the idea of somehow or the same being being still technically of its former identity once this application has been made is questionable at best (when you take someone's brain and "Frankenstein" its ability to live and then relay it elsewhere somehow, can you argue that this is still of its natural-born identity?);

The two above differences take in to account the obvious notion that brain as a natural form is subject to decay and death as it is biological naturally (without factoring in anti-aging and other methods). The idea might stand to bring up the possibility of femtotechnology or etc. to recreate brain neural network copies and then attempting to figure what to make of the conscious bridge that forms one with mind.

To upload information stored in the mind is to upload information stored in the brain because the brain is the physical part of the mind. To do this is not an easy task because the brain has neither output port nor functional modules for this purpose (to upload its information), and the information in the brain is not stored in one definite place like a hard drive or a series of memory banks in a computer but is stored scatteredly in neural circuits all over many areas of the brain, with 100 billion neurons and about 100 to 1,000 trillion synapses making up those neural circuits [1,2]. So, it certainly won’t be easy like uploading information from our computers to elsewhere.

Another problem is that current technologies that can gather information from the brain, such as EEG, MEG,  and electrocorticography, are very crude (they cannot single out a specific neural circuit that contains the specific information) and cannot access information in all parts of the brain, especially that in the deep structures. Single-unit neural recordings are much finer and can record deeper, but we have to do such recordings possibly millions of time to get all the information from all information-containing neural circuits in the brain, which will certainly do some damage to the brain (and its mind). So, this seems to be quite a harmful way to upload information from the brain.

Another significant problem is that the information in the brain are in various forms: declarative memory (which also has many types: immediate memory, working memory, and long-term memory) and non-declarative memory (skills, habits, predilections,etc.) [3]. They are are stored in different types of neural substrates: neural signaling patterns, facilitation/inhibition of corresponding neural synapses' strength, modifications of neural circuits' formation, etc. The information that is stored in the form of neural synapse or neural circuit modification is not free to read directly but has to be converted into neural signals before it can be read by other neural circuits and by our instruments. So, the problem is we have to activate all those neural circuits/synapses before we can read their information. But how do we know which ones of those multitude neural circuits/synapses in the brain store information, and how we do that to all several millions of them?

What’s more, current technologies still cannot decipher accurately what exactly the signals that are  gathered from the brain mean, e.g, what do those EEG/MEG signals mean – a vision of the red color?, a house?, or a man? So, without knowing what the information we’ve got represents, it is difficult to store and archive it correctly and retrieve it later effectively.

Edited part:

Because all the above problems are technical problems, I think it is theoretically possible to overcome them although it certainly requires much more advanced technology than we currently have. And it seems very likely that we will not have that technology in the near future, certainly not within a few decades from now.

The biology problem and the hard problem of consciousness and qualia.

It is important to note that the above discussion is about the possibility of uploading information of the mind to a computer, which is arguably theoretically possible. But to upload or relocate the mind itself to function or live in a computer is another matter because it will face additional 2 formidable problems: the biology problem and the hard problem of consciousness.

The biology problem:

The mind and its physical brain are alive; they change their structures to some degree overtime by neural circuit and synapse modifications to store new information or modify its skills, habits, predilections, etc. On the contrary, the computer is not biologically alive and cannot change or modify its structure (hardware) by itself. So, even if we can upload all the mind’s information to the computer successfully and try to set it function there, the mind can never really live in the computer the way it lives in the brain, where it can modify its self bit by bit overtime.

The hard problem of consciousness and qualia:

This is the problem of having phenomenal perceptions (the red color, the sound of music, the smell of the rose, etc. that appear phenomenally red, phenomenally music, phenomenally rose, phenomenal etc. in our mind) and phenomenal consciousness (the awareness of what it is like to see the red color, to hear the sound of music, to smell the rose, etc., and what it is like to be ourselves)[4] Although we have learnt a lot about neural correlates of consciousness [5], we still do not know how these non-material phenomenal manifestations occur from the material neural circuits. Some new theory explains that they are special kinds of information, which is non-material, that occur inherently in the material neural circuits [6], but this has to be verified by experiments.

Because both the biology problem and the hard problem are fundamental problems, if we cannot solve these problems first, we will never be able to upload or relocate the mind itself to function and live in a computer like the way it lives naturally in our brains.

References.

Byrne JH. Introduction to neurons and neuronal networks. Neuroscience Online. The University of Texas Health Science Center at Houston (UTHealth).
Sporns O, Tononi G, Kötter R. The human connectome: A structural description of the human brain. PLoS Comput Biol. 2005 Sep;1(4):e42.
Purves D. Chapter 30. Memory. In: Purves D, Augustine GJ, David Fitzpatrick D, Hall WC, Lamantia AS, McNamara JO, Williams SM, editors. Neuroscience. 3rd ed. Sunderland, Massachusetts: Sinauer Associates Inc; 2004. ISBN-13: 9780878937257 ISBN-10: 0878937250.
Chalmers DJ. Facing up to the problem of consciousness. J Conscious Stud. 1995;2(3):200-219.
Koch C, Massimini M, Boly M, Tononi G. Neural correlates of consciousness: progress and problems. Nature Reviews Neuroscience. 2016;17: 307-321. The full pdf file can be downloaded from here.
Ukachoke C. The Basic Theory of the Mind1st ed, 2018. p 8-18. Charansanitwong Printing Co. Bangkok, Thailand.


Can attention be improved to reduce the frequency of mistakes? There is a class of error that is sometimes colloquially referred to as "not paying attention". These are the sorts of error where the subject knows the correct way to perform a task, but fails to follow it due to a lapse in whatever mental process is responsible for ensuring that actions are carried out according to intention.

Some examples are:

A mathematically competent adult solving an advanced math problem incorrectly because of a simple arithmetic mistake, such as 5+3=15.
A well-prepared student getting a multiple choice question wrong because it was asking "which of the above are not true", but she mistakenly selected the ones that are true.
A skilled roboticist damaging an expensive circuit because he accidentally wired the components incorrectly.
Mixing up two terms which refer to different things, despite understanding very well the concept that either term refers to.
Typos and simple grammar errors.

Note that I do not necessarily mean attention in the sense of being able to concentrate on and pay attention to a topic. I am specifically talking about the ability to not make mistakes (where mistakes are simple errors, which the subject is capable of recognizing as errors, but happens not to in that particular instance - not errors committed because of imperfect knowledge, understanding, or reasoning). Thus, "mistakes" are:

Not reproducible: If the subject is asked to repeat the task, they will probably do it correctly.
Unrecognized: The subject believes that the task was completed correctly, until explicitly checked.
Paradoxical: If asked about how the task should be performed, the subject answers correctly - but occasionally fails to perform as described.
Mental: The mistake is not due to failures in fine motor control but has to do with the output of the mind. The mistake may be due to incorrect interpretation of sensory stimulus, but not due to an overt corruption of the stimulus itself (a person with good vision "misreading a word" in a brightly lit room from a black on white page with a suitably large font counts, but trying to read by starlight on a moonless light doesn't).

So, my question: Is there scientific research dealing with "attention" in this sense (ability to make few mistakes)? What factors influence it? Can it be trained, or is it an innate, invariant quality of a person that can only be accepted and accommodated?

Also, I am asking specifically about "healthy and normal adults", not disorders such as ADHD (unless the pathology helps elucidate the healthy case). As the saying goes, to err is human - but some humans err more than others, and I am interested in understanding why (and what strategies are available to reduce this tendency).

(edited from my original question on Academia.SE)

Sounds like a class of faults resulting mainly from a common sequence: habituation, automation, assimilation, discrimination error.

Habituation. The tasks you describe are generally simple, ordinary, and as you say, there is a "correct" way to do them that is known. This would encourage a heuristic-based approach to problem-solving response generation. Heuristics are generally not foolproof, but they're fast and relatively effortless. Suits these "mindless" tasks well when there are lots to do that just need doing.
Automation. The easier and more routine a task becomes is the more one will handle it without conscious, deliberate thought: i.e., without attention to detail or inhibition of first-impression-based impulses. One focuses instead on other decisions or plans; there's always the rest of the week to look forward to or worry about, and the task at hand is so boring that focusing on it is aversive.
Assimilation. Rote task performance that thus motivates diversion of attention for the sake of both efficiency and entertainment thereby encourages assimilation of new stimuli. In many ways, this process actually comes first, leading to habituation and automation. I bring it up now to transition my focus from the learning processes to the case-by-case response pattern that results. Assimilation is the foundation of habituation and automation, but it also results, as these are the processes of self-reinforcing feedback from assimilation decisions. More simply stated, when assimilation happens often, habits form. As habits flourish, automaticity sets in. At this point, one almost always chooses to assimilate a new scenario into existing schemas; it's harder to resist the urge.
Discrimination error.
Motivated inattention and hastened task processing inhibits accommodation. Thus when one operates on an imperfect heuristic (that may be redundant), applying incomplete schemas to new situations that are not represented accurately in these classes of supposedly known problems leads to errors. E.g., seeing a ton of multiplication problems might bias one toward ignoring the operator, failing to notice a 45º rotation of the symmetrical cross shape, and producing 15 when presented with $3+5$. Being frustrated with my elaborate jargon and complex sentence construction might incline a reader to skim; if the reader's intended task is to edit, s/he might expect more errors where errors are to be found, and in skimming, miss the extra word in a the sentence that constitutes an error. After frequent experiences of assimilation produce automated habits, one can hardly be blamed; the tendency is innate, adaptive, and somewhat invariant in terms of simple prevalence. I.e., most normal people do it, and variation mostly exists in relative frequencies $>0$.

Excluding abnormal individuals might make the phenomenon more invariant. Abnormal function like in the cognitive tendencies of people with obsessive compulsive personality disorder might present stronger exceptions to the rule that "everybody makes dumb mistakes sometimes," even somewhat often. But then again OCPD might not be such an exception, as its theoretical representations don't entirely match its real manifestations. (Same for its fictional representations; see my answer to Why is Mr. Monk unsure?)

I'm sure plenty of research can be found on how to encourage adaptive accommodation to prevent errors. I'm inclined to look toward motivation- and personality-based approaches, as those are my specialties – hence you might say they inform my own schemas and heuristics, encouraging me to assimilate your problem as just another of the kind I'm familiar with. If I fail to respond appropriately to any subtleties in your question as a result, consider it a demonstration! I admit I've spent most of my time so far on just reformulating and recapitulating the issue you describe.

Moving briefly into some modification strategies then, consider motivating attention. This can be achieved by increasing the sense of challenge to optimal levels that induce flow, which is a state of very intense, self-motivated, even blissful focus. Just produce the challenge by requiring higher accuracy, not faster task completion.

On somewhat less modifiable notes pertaining to individual differences in error frequencies, conscientiousness and cognitive complexity seem like relevant traits. Conscientiousness relates to attention to detail and concern for error prevention. Cognitive complexity relates to adaptive thought and tolerance for complex or multitudinous schemas, which would discourage over-application of too-simple schemas for every problem encountered.


Are there advantages of psychopathic traits? After watching a fairly engaging 2016 TEDx talk titled "Psychopaths and three reasons why we need them" I was hoping to read more systematic/traditional research output from its author, Armon Tamatea. But looking through his publications list I was rather disspointed there wasn't anything obvious since that talk. So, in my vague summary of the talk (I didn't take notes), he mentioned that psychopaths have some useful traits, including

coolness under pressure
being good at spotting vulnerabilities in people or organizations
superficial charm that can oil the social machinery in many occasions

and probably some I've missed.

I see there's a pretty similar talk "Your Friendly Successful Psychopath", which makes reference to The Wisdom of Psychopaths, but I'm not familiar with the book... but a summary in The Guardian goes like:

  Dutton's book at any rate supports the idea that to thrive a society needs its share of psychopaths – about 10%. It not only shows the value of the emotionally detached mind in bomb disposal but also the uses of the psychopath's ability to intuit anxiety as demonstrated by, for example, customs officials. Along the way his analysis tends to reinforce the idea that the chemistry of megalomania which characterises the psychopathic criminal mind is a close cousin to the set of traits often best rewarded by capitalism. Dutton draws on a 2005 study that compared the profiles of business leaders with those of hospitalised criminals to reveal that a number of psychopathic attributes were arguably more common in the boardroom than the padded cell: notably superficial charm, egocentricity, independence and restricted focus. The key difference was that the MBAs and CEOs were encouraged to exhibit these qualities in social rather than antisocial contexts.

Of the one more clearly identified research, the analogy with the CEOs sounds a bit doubtful to me in view of research of Fred Kiel finding the opposite being true, i.e. psychopathic-like CEO traits producing negative outcomes in business. So, yeah, I'm curious of the meta-analytical status of such claims, assuming there's enough research for review-like works.

Is there some systematic research that finds there [or other potentially desirable traits] are really more common in psychopaths? Of course for some of the traits one needs to ask "advantageous for who?" or "in what context?", because they may be advantageous in the short run for the self, but might harmful for society/others, so there may be negative consequences for the self in the long run as a result. So I'm guessing a more sophisticated question would be if there's some kind of evolutionary stable strategy that favors a percentage of psychopathic traits...

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

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

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

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

  emotionally detached mind in bomb disposal

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

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

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

Carolin Showers (1992) described compartmentalisation as

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

Similarly the

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

could also brand doctors and therapists as psychopathic.

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

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

References

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

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

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

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

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

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

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

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

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

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


Are mnemonics by creating associations good for memory? I read a book which says that to remember the lists of arbitrary objects, we should take a well-known ordered list (so that you know what is on the first place, what is on the second) and associate the items of this familiar list with your target list items. This is especially important for abstract objects because our brain can memorize only visual pictures (you can visualize familiar things). For instance, instead of directly memorizing the 10 abstract amendements to (US) constitution, (1.Freedom of Speech, 2.Right to Bear Arms, 3.Protection From Quartering Troops, 4.Freedom from Unreasonable Search and Seizure, and etc), you translate them into a list of visualizable amendment images, (1. Speaker, 2. Gun, 3. Soldier, 4. Spotlight, 5. A picture of you, 6. Judge riding a fast motorcycle, 7. Jury, 8. Excessive amount of money, 9. Making a right turn with your hand over your mouth, 10. State Capitol building). Then, you come up with another, well-known list of visualizable loci objects, e.g. (head top, nose, mouth, ribs, liver, joint, cap, fibula, ball, sand),

Finally, you invent 10 stories, to map the loci items to the amendment images. In overall, ordered loci list serves as a list of keys that we can iterate and, by means of vivid stories, map to the target abstract items.

Yet, I see that you memorize 4 lists (original list, keys and images and stories) in place of single amendment list alone. This is 4x more information. It would be ok if the associations were natural and teach me the world around me. However, they must be absolutely bizzare because they do not exist, unnatural and, secondly, the outlandish pictures are much better memorizable (they call this thinking out-of-the-box)

Also, inventing the stories is too creative task for me. I feel like I waste too much mental energy to create garbage, the stupid associations in my head. Is it right? Won't this mnemotechnique create a mess in my head?

ps

Idriz Zogaj, Daniel Kilov and Joshua Foer are memory athletes that popularize the approach in TED conference.

Just a few words on mnemonics before answering your question. I have been practicing for two years. First because I was impressed how easy it was to remember items using these techniques. My personal best time for learning the order of 52 cards is 1min 40s, which is not really good compared to real competitors, but the point is that practicing 30min a day during 3 months can be enough to get this kind of performances. Of course to do that you have to learn a code that binds numbers or cards to predefined images. I can't be more specific because I would risk to be off topic.

However don't expect too much from these techniques concerning real world knowledge. With training you can learn fast as hell a list of words, but learning more semantic knowledge is - I think - more challenging. If you find good images, It can provides you a perfect recall, but you would need spaced repetition to ensure it on the long term. If you don't repeat, you take the risk to loose everything you learned, more than with classic methods I think. Unfortunately, I don't have many sources apart from my experience and experiences of friends to back up this claim. However, I found a study by Wang et al. (1992) cited in part 7 of an interesting review on learning techniques by Dunlosky et al. (2013) which found this effect on the use of mental imagery on vocabulary learning. There is no absolute proof that mnemonic techniques can  work for everything, but (1) it's interesting to see how it works (2) it is funny, especially memory palace building (3) if you spend enough time to learn a code, you can learn phone numbers, credit cards, poker odds and things like that very easily.

Concerning your practical questions, a good approach would be to check how the community proceeds to use mnemonic strategies. Have a look on the Mnemotechnics Forum on ArtOfMemory.com
 for example or their wiki. I think you would get more reliable advices than in books. For example the peg technique you mention (i.e. loci object in your words) is clearly less popular than the use of real place as locis. It has two main advantages :

It provides a good organization (your list order follows the spatial order of your locis). Then to remember your list, you just have to do a mental travel.
It is easier to store an image in a place, no need to find specific association, just picture your mental object like if it were really in your loci and let the magic happen.

Then, to answer your question, you really just need to memorize 1 thing : the images. Loci are just a powerful way to retrieve these images, like a storing device. Images are chosen to be firmly tied up with the item you want to learn so you don't have to spend time to learn the association you made.
Images don't have to be 'absolutely bizzare', it makes things more memorable but it's not an absolute condition. Trying to prove this, a study found no effect for learning a list of words, but I don't have the reference now. Same remarks for the stories. It makes things more memorable, and can provide you some links between the images, but again it's not an absolute condition. Moreover, stories can be very short, like a simple action or context linking the image 1 and the image 2.

You should not waste time and energy on creating associations. On the opposite, you should relax and let them come to your mind, and take the first things popping up. This kind of creativity is not a sort of adult-creativity for which time and work is needed, but rather a sort of child-creativity for which you just have to let your imagination take the control of your thoughts. It should not be a painful task, on the contrary, you should get some fun.

Wang, A. Y., Thomas, M. H., & Ouellette, J. A. (1992). Keyword mnemonic and retention of second-language vocabulary words. Journal of Educational Psychology, 84(4), 520.
Dunlosky, J., Rawson, K. A., Marsh, E. J., Nathan, M. J., & Willingham, D. T. (2013). Improving students’ learning with effective learning techniques promising directions from cognitive and educational psychology. Psychological Science in the Public Interest, 14(1), 4-58.


Why does clickbait use numbers? Around the Internet, especially in social media, we see examples of hyperlinks in a common format that has been cynically dubbed "click bait" or "link bait".

The idea is that authors publish these links with evocative titles, trying to entice a casual browser into clicking the link and viewing the content (where the resultant loading of the advertisements presumably earn some small amount of money for the content provider).

Some examples of click bait (with links removed, to protect everyone's sanity) are:

  Watch out, these 15 baby penguins are waddling off to steal your heart.
  31 creative life hacks every girl should know
  20 Powerful D-Day Photos On The 70th Anniversary Of The Invasion
  11 Sexy Star Wars Tattoos

Many of these kind of links use provocative phrasing, like "you won't believe" and "will shock you". I can see intuitively why this works to entice people to click the link.

What is the reason for giving a number, like in the examples? Is there any psychology involved in this trend?

This question comes from someone who doesn't really know anything about psychology or cognitive science; I'm just interested.

Digital Marketing often produces 'content' for users to consume.
That content is ment to catch and keep the attention of the user, in an attempt to make the user trust and follow the sender (usually a website or blog).
When the user shows engagement like clicking the right buttons, the user will somehow be tempted with some kind of offer (a newsletter, a free ebook, etc). If the user takes that bait, there will later be an offer to actually buy something.

The whole idea here is to catch and keep the users' attention.
One of the most common ways to achieve this, is by making lists of something the user might want to read\see.
In order to have users click(open) the content to begin with, the writer needs to make the content seem valuable in only 1 short line.
By typing the number of entries on that list, the writer is trying to make a point: There's stuff to see her, come check it out!


Big 5 personality traits means and SD I'm looking for a fairly large (250+ people) study that gives the raw mean and sd of the 5 different big 5 personality traits (using whatever scale they choose in that paper) or just gives the raw data that I can use to calculate those values. I don't mind if it's split up into men and women as I already have data for the differences but I can't find any about the underlying distributions for each of the personality traits.
Thanks in advance, please ask if any clarifications are required

Means and SDs are going to vary based on the specific personality measure, the measurement context, and the sample.
Many of the thousands of journal articles that measure Big 5 personality will report descriptive statistics for their measure.
In terms of some available raw data for the Big Five.
Here is some based on IPIP data:
https://openpsychometrics.org/_rawdata/
Here are a bunch of repositories with Big 5 data:
https://osf.io/4mruh/
https://osf.io/4mruh/
https://osf.io/62gs7/
https://osf.io/cwbgv/
https://osf.io/daext/
https://osf.io/qjd48/files
https://osf.io/qk4r9/
https://osf.io/qk4r9/


Is epigenetic the study of environment/genome interaction? I have troubles understanding epigenetic: to me it seems like the study of environmental factors that change the expression rate of some genes. Therefore, it seems that it is the study of environment/genome interaction.

Is it a correct interpretation or is my reasoning flawed?

Thank you so much in advance!

Epigenetics is the study of changes in gene function, from parent to offspring, that do not involve changes in the DNA sequence. (Source: Wikipedia)

  In the original sense of this definition, epigenetics referred to all molecular pathways modulating the expression of a genotype into a particular phenotype. Over the following years, with the rapid growth of genetics, the meaning of the word has gradually narrowed. Epigenetics has been defined and today is generally accepted as "the study of changes in gene function that are mitotically and/or meiotically heritable and that do not entail a change in DNA sequence. (Dupont, 2009)

The term "epigenetic" has also been used in developmental psychology to describe psychological development as the result of an ongoing, bi-directional interchange between heredity and the environment. (Source: Wikipedia)

Within Psychology and Psychiatry, epigenetics covers areas of early life stress, addiction, anxiety, depression and fear conditioning.

Caspi et al. (2003) demonstrated that in a robust cohort of over one-thousand subjects assessed multiple times from preschool to adulthood, those who carried one or two copies of the short allele of the serotonin transporter promoter polymorphism exhibited higher rates of adult depression and suicidality when exposed to childhood maltreatment compared to long allele homozygotes with equal early life stress exposure.

One study suggested that traumatic experiences might produce an epigenetic signal that is capable of being passed to future generations. Mice were trained, using foot shocks, to fear a cherry blossom odour and the investigators reported that the mouse offspring had an increased aversion to this specific odour. (Dias & Ressler, 2013)

Addictions can arise from transcriptional and neuroepigenetic mechanisms. (Robison & Nestler, 2011)

There is caution to be made however, when looking at literature on epigenetics. Some literature has been found to be pseudoscientific as some authors have made unfounded claims that a person's genes and health can be manipulated by mind control. (Gorski, 2013)

Also, several criticisms were reported on the Dias & Ressler study, including the study's low statistical power as evidence of some irregularity such as bias in reporting results (Francis, 2014). The authors also did not indicate which mice were siblings, and treated all of the mice as statistically independent:

  The statistical tests in the paper, both for the behavioral measurements as well as for the size of the M71 glomeruli , use as n, number of samples, the number of F1 and F2 individuals. This would be fine if the individuals were actually independent samples. However, they arise from a presumably small number of FO males. The numbers of FO males are not given in the paper. This is a major concern given that there is a lot of variability in the levels of expression of olfactory receptors in these mice that might be inheritable. As an example, for Figure 1a, the authors compared 16 F1-Ace-C57 mice with 13 F1-Home-C57 mice and find a p value of 0.043, with 27 degrees of freedom . But these 29 mice could have been originated from a very small number of FO mice. The actual n that should be used for the statistics in the whole paper are not the individual number of F1 or F2, but it should be the number of founding F0, for both groups. So the actual p values are larger than reported. Without the information about the size of the F0 populations used in each figure panel, it is hard to interpret the results. (Source: PubMed Comment by Gonzalo Otazu)

References

Caspi, A. et al. (2003). Influence of Life Stress on Depression: Moderation by a Polymorphism in the 5-HTT Gene. Science 301(5631), 386–389DOI: 10.1126/science.1083968. PMID: 12869766.

Dias B. G. & Ressler, K. J. (2013). Parental olfactory experience influences behavior and neural structure in subsequent generations. Nature Neuroscience 17, 89–96DOI: 10.1038/nn.3594

Dupont C., Armant D. R. & Brenner C. A. (2009). Epigenetics: definition, mechanisms and clinical perspective. Seminars in Reproductive Medicine 27 (5): 351–357. DOI:10.1055/s-0029-1237423 PMCID 2791696 PMID 19711245.

Francis, G. (2014). Too Much Success for Recent Groundbreaking Epigenetic Experiments. Genetics 198(2), 449–451DOI: 10.1534/genetics.114.163998

Gorski, D. (2013). Epigenetics: It doesn’t mean what quacks think it means. Science-Based Medicine [Online]Available at: https://sciencebasedmedicine.org/epigenetics-it-doesnt-mean-what-quacks-think-it-means

Robison, A. J. & Nestler, E. J. (2011). Transcriptional and epigenetic mechanisms of addiction. Nature Reviews Neuroscience. 12(11), 623–637.DOI: 10.1038/nrn3111 PMCID: 3272277 PMID: 21989194


Reporting d-prime results I am currently working on research analysing yes/no responses in a recognition memory task. The false alarm rate is quite high so I have performed a d-prime test and collected d-prime values. Now that I have these d-prime values I do not know how to analyse/report these findings as I have a d-prime value for each individual participant. Some papers show a comparison using an ANOVA but I do not know how to conduct this comparison with the d-prime data or if this is what I should be doing, should I be using the mean of my d-prime values? How should I go about reporting my d-prime results?

d-prime values are usually fairly well normally-distributed. So you can use any parametric test relying on the normality assumption (in facts you should always z-transform fractions before to use a parametric test on them). If you have only 2 conditions you can use a classical t-test. From your question it seems you have only 1 value per participants so that would probably be an independent t-test. If you have more than 1 comparison an ANOVA would be the typical test to use.

For reporting results it is a bit tricky. d-primes are not that intuitive for people. So you might want to report fraction correct in the text, but run your tests on d-primes. For the same reason you might want to plot your results as fractions. Below is an example of wording (but refer to a statistical textbook for conducting and reporting statistical tests). Note that it is fine to report means and standard deviations of fractions. However parametric tests should always be conducted on z-scores. I know people use fractions in tests all the time but it is wrong.

  The mean recognition rate increased from NN% to NN% between the conditions ... and ..., for a mean improvement of NN ± NN% (SE). This difference was significant in an independent t-test on z-transformed recognition rates: t(N)=N, p


Term for the tendency to relate events that occurred in proximity? What is the correct scientific term for the tendency to wrongfully relate arbitrary observations to a significant event, just because they occurred in temporal or spatial proximity?
Most recently I have observed this error in a discussion about an unsolved killing, where a participant was quite sure that her observation of a black van in a far away town was related to the killing, for the single reason that it occurred around the same time.

This is informally referred to as the illusion of causality:

Illusions of causality occur when people develop the belief that there
is a causal connection between two events that are actually unrelated.
Such illusions have been proposed to underlie pseudoscience and
superstitious thinking, sometimes leading to disastrous consequences
in relation to critical life areas, such as health, finances, and
wellbeing.

This is a cognitive error in the way humans infer cause and effect.
The example that I'm most familiar with is in medical quackery.  Suppose someone is experiencing constipation.  They try some advice from friends: Go for a long walk, eat some prunes, massage their stomach, use magnesium supplements.  Then they try more questionable solutions: Probiotics, colon hydrotherapy, acupuncture, herbal medicines.  At some point during the process, the constipation is relieved, and the patient naturally concludes that whatever treatment immediately preceded this event must have been the cure.  They "swear by this treatment" from then on, failing to consider that prior treatments may have needed more time to take effect, that other activities not considered treatments may have affected the results (eg, regular exercise, dietary changes), or simply the mere passage of time.


Best ways to improve memory I've once watched a movie in which CIA agent went into a room just for a few seconds and on the next day he could recall every detail of that room, including what was on the monitors.

And I am wondering is there a way to improve my memory to this level?

I would also like to know if there are studied ways of accomplishing this.

There also is something that I remember reading few years ago about training visual memory:

"You go into a dark room with a page of text and a flash light, and every ~30 seconds you turn on and off the flash light very quickly and try to recall as much as you can. And you do this for ~20 minutes. After ~30 days of practice you should have much better visual memory."

What do you think about this method. Could it really work? And if so, could this ability disappear after some time without practice?

Your best bet is to start looking on YouTube and the Internet for various memory methods used by card memorizers, magicians, and other stunt people.  I have used them extensively, and they work.  You can also look on Amazon for books.  Tony Buzan, Harry Lorraine, Dominc O'Brien. Also the book Moonwalking with Einstein.

Don't believe all the nonsense out there about your limited memory, or it takes years of practice, or you need special supplements.  I've met SEALs who used the simple techniques taught in the books to help them.  It worked for them.


Can incubation be facilitated, while, at the same time, being focused on a different problem? Is it possible to facilitate incubation as well as consciously think about a different problem at the same time, in effect multitasking, in order to gain insights more quickly, without having to stop and take a break.

For context, see this question on incubation:

How is it that taking a break from a problem sometimes allows you to figure out the answer?

This is an interesting question because it relates to different mechanisms that may be responsible for incubation effects:

Does incubation occur because creative insight is helped by unconscious processes? (Processes that are best left undisturbed by not consciously thinking about the problem?) In this case, the most important thing would be to focus on something else.
Or does taking a break simply reduce mental fatigue as some have claimed (e.g., Posner, 1973, as cited in Sio & Ormond, 2009)? In this case, just taking a break from thinking might be best.
Or is it because of certain patterns of conscious thought during incubation? In this case, the kind of problem one thinks about consciously during the incubation phase would matter.

Sio and Ormond (2009) have looked at this question as part of their meta-analysis of incubation studies:

They found that performing low cognitive demand tasks were associated with stronger incubation effects than just taking a break and doing nothing
However, high cognitive demand tasks were associated with smaller incubation effects

These results are not in line with a simple mental fatigue account of incubation. Instead, they suggest that creative insight profits more from distracting tasks that are low in cognitive demand.

One explanation for these findings is that low demanding tasks allow and promote mind-wandering (Baird et al., 2012).

Conclusion: So based on this research, when trying to generate some creative insight, it might be good to take a break after an intense preparation period. However, instead of occupying your mind with another hard nut to crack, it might be better to do so with something that is not very demanding. Try cleaning up your desk and water those sad-looking plants in your office!

References

Baird, B., Smallwood, J., Mrazek, M. D., Kam, J. W. Y., Franklin, M. S., & Schooler, J. W. (2012). Inspired by distraction: Mind wandering facilitates creative incubation. Psychological Science, 23, 1117–1122. doi:10.1177/0956797612446024

Sio, U. N., & Ormerod, T. C. (2009). Does incubation enhance problem solving? A meta-analytic review. Psychological Bulletin, 135, 94–120. doi:10.1037/a0014212


The belief becoming the self Is there a terminology or specific topic that explains the behaviour or phenomenon expressed in the following quote?

  The greatest anomaly of belief is that it is so powerful it takes over
  the identity of a man. People of belief  believe so strongly that they
  become the belief. They are the belief. So  anything or anyone that
  questions their belief is taken as a personal  attack on themselves
  and their person. Belief is so powerful and deeply set in delusion
  that even if presented with verifiable proof and facts to the
  contrary; the believer reacts with emotional outburst ranging from
  anger to rage to violence even murder. In the case of phylogenetic
  group or culture insanity it leads to war and genocide.

If I have understood things right, I think it is some form of 'Cognitive dissonance'

According to wikipedia,"cognitive dissonance is the mental stress or discomfort experienced by an individual who holds two or more contradictory beliefs, ideas, or values at the same time, or is confronted by new information that conflicts with existing beliefs, ideas, or values"

I remember experiencing the feel in one of the Ayn Rand books. As kids, our basic belief would be that our parents love us the most. Their love is the purest form of unconditional love. No matter what you do, they will always love and be for you for what you are. Suddenly , one day you wake up to the fact that the belief you have is entirely foolish. Your parents love you not for 'what you are' but just because 'who you are - their child'. You question yourself if your parents(as persons) would love you the same way if you had not been their kid. Because the answer to the question is a simple no. I cried at the very thought. Our mind tries to defend the previous comforting belief and disprove the new bitter realization and then helplessly experience outbursts.

This is more seen in case of religious beliefs as said in the quote. Your deep rooted beliefs are shattered and the mind can't smoothly accept the new version - Cognitive Dissonance, as they term it.


Is there a function between loss of memory and time? I have 2 related questions with regards to memory capabilities and time:

"Is there a function (e.g. $e^{-\Delta Time}$) with regards to memory loss?" Everyone is bound to forget over time. Is there a function that describes this decay?
"Is there a function between time spent looking at something and remembering it?" The more the time I spend trying to remember something, the better I will be at it. Is there any correlation between the two?

There is substantial research on both the functional relationship relationship between practice and retention and between time away from task and forgetting (e.g., see forgetting curve).
In general, retention is a monotonically increasing and monotonically decelerating function of  practice. And retention is a monotonically decreasing function of time where the rate of deceleration is decreasing. This general finding is tremendously robust, but there is substantial debate about the best fitting functional form for these two relationships.

Averell and Heathcote (2011) provide a good review of forgetting curve functions. See equations 2, 3, and 4 in the article for instances of pareto, power, exponential functions. They concluded:

  Our analysis revealed that, although for individual participant data
  the exponential function with an above chance asymptote had the best
  fit among the models we considered, this advantage was due to its
  extra flexibility (complexity). When we adjusted for complexity using
  a range of model selection techniques that varied in the degree to
  which they adjusted for complexity, in every case a power function
  with an above chance asymptote provided the best description of
  forgetting. Interestingly, previous analyses of retention functions
  without an asymptote (Lee, 2004) found that the power model was more
  complex than the exponential. Our findings suggest that the addition
  of asymptote parameters adds more complexity to the exponential
  function than the power function.

References

Averell, L., & Heathcote, A. (2011). The form of the forgetting curve and the fate of memories. Journal of Mathematical Psychology, 55(1), 25-35. PDF


Understanding a negative correlation between Pc and signal strength When I present two signals in paired comparison and ask the respondent to select the stronger signal in the pair, I find that it is the signal strength of the second signal that more so determines correct detection (0,1) yet the correlation between probability of correct detection (p) and both signals is significant and negative. Yes, the contrast contributes to the prediction of (p) but I cant figure out why my correlations are negative. It is as if the respondent is anchoring on the first signal and the "smallness" of the second signal determines (p). Does anyone have an explanation for this?

Experiment backgrounds

The stimulus is paired comparison words with each having a different factor loading based on it's measurement of agreeableness. So each word taps the construct more or less deeply than the other;
The contrast between the words in terms of their factor loading is the signal;
A set of 122 such paired comparison tasks was developed and the task before the respondent is to select the more agreeable word.
The stronger loading was alternated between being on the first and second word. I did find that the contrast predicted probability of correct detection (r = .20*). I know this is an unusual application of signal detection theory and you might not has seen this before.

I find that it is the signal strength of the second signal that more so determines correct detection (0,1)

The ideal unbiased observer bases the decision on $X1-X2$ while it sounds like your subjects are basing their decision on $aX1-X2$ where $a < 1$. While it is suboptimal, it is not a big deal. The fact that you know it means either report it or train the subjects out of it.

  the correlation between probability of correct detection (p) and both signals is significant and negative.

If the first stimulus is very weak, the difference between it and the second stimulus will on average be larger than if the first stimulus is of moderate strength. One would therefore expect Pc to initially decrease as the strength of the first stimulus decreases. Additionally, if the first stimulus is very strong, the difference between it and the second stimulus will again be larger on average than if the first stimulus is of moderate strength. Therefore, for an ideal observer, the dependency of Pc of the strength of the first signal should be non-monotonic. The same holds for the second stimuli.

We know from the above statement that your subjects are not ideal. If the bias depends on the strength of the first signal (i.e., $a(X2)$ increases with X2) then the non-monotonicity of Pc on the strength of the stimuli could be hidden.


Beyond a certain level, is reading comprehension affected more by psychological intuition than by verbal intelligence? Certainly, you have reading comprehension passages on the SAT, GRE, and LSAT. But beyond that point, is it really possible to measure reading comprehension through multiple-choice tests? There are multiple motivations for why an author may make argument X, and multiple interpretations of his exact argument, which may be affected by the immediate circumstances that made him write that argument at that particular point in time (and while we may know a bit about the society that he lived in, chances are that we'll probably never know who he intended the book to be written for - hell - some people probably intended to write a book to impress some potential lover [and hell, maybe some passages in the book are motivated to attract the sympathy of that lover] even though they pretended to write it for the greater good of society).

I mean, all you have to do is to look at courtrooms. There, people pretty much argue about what people (in a case with precedent) actually meant, and there's usually no concrete (and correct) answer. And people who study the life of a particular philosopher may have multiple interpretations of why philosopher X wrote passage Y, and what X really meant in writing passage Y.

Plus, it's oftentimes very interesting to read the writing of someone you know REALLY well because you know their life so well that you can dream up hypotheses of what prompted them to write passage X at time Y (and you also know his social network so you could imagine what audience he had in mind, and what audience he might have secretly hoped to impress without mentioning it). And perhaps because of this, reading comprehension is not a skill with a single scale, since people are better at understanding some people than they are at understanding others.

I mean, I guess the ultimate test of reading comprehension would be to test someone on one of Immanuel Kant's books, or on some recent postmodernist book (made artificially difficult to read/parse), and then ask him "well, what is Kant trying to get at"? But is that really a valid test? Or maybe one where you have to dissect the entire structure of a book where X is pretending to be Y pretending to be Y pretending to be X (of course, such books are rarely written, but theoretically possible).

Alternatively, wouldn't someone with exceptional reading comprehension be better at reading crappy writing? (because they're probably more able to process multiple thought-streams at once - which includes possible fragmentary/jumbled ideas?) A common assumption in reading comprehension tests is that the writing is "perfect", but this is frequently not the case, and people (especially older people) can get attention lapses when writing

The assessment of reading comprehension is not my main area of interest, but some of the many articles on the topic of assessment of reading comprehension may be reflevant. See "measurement of reading comprehension" on Google Scholar (e.g., a couple of the pdfs of reviews here, and here).

This entry in the literacy encyclopedia on assessment of reading comprehension might be a good starting place.
The article has a the following quote of a definition of reading comprehension:

  The National Assessment of Educational Progress (NAEP) 2009 Reading Framework Committee defines reading   comprehension as ...“an
  active and complex process that involves understanding    written
  text, developing and interpreting meaning, and using meaning as
  appropriate to   type of text, purpose and situation (National Center
  for Educational Statistics, 2005, p.    2).

Here are a few general points:

Multiple choice testing has the benefit of being reliable given a sufficient number of items. Of course, questions could be raised over the breadth of what it measures (i.e., validity issues).
Familiarity with the content should increase reading comprehension. Thus, to build on your question, a philosophy student should comprehend more Kant, than a non-philosophy student holding general reading ability constant. A similar argument could be made where the reader has insider knowledge about what the author is trying to say.
Some texts are more difficult to comprehend in general, whether it be because the text is poorly written (e.g., grammar, spelling, stylistic issues) or because of the complexity of the material.

Implication of the Rasch model to questions of measurement:

A basic model of responding to multiple choice questions based on Item Response Theory (IRT) is the Rasch model. It basically says that the probability of an individual getting an item correct is a function of their ability and item difficulty.

So according to this model, increasing the difficulty of the reading comprehension items would affect all individuals roughly equally. As can be shown with IRT the reliability of measurement can be increased by setting the difficulty of items to a level that discriminates between individuals. I.e., if items are too difficult, everyone gets the item wrong, and we don't learn much; likewise, if the item is too easy, everyone gets the item right, and we don't learn much.
Relating this to your question, including poorly worded writing or really difficult subject matters would only increase difficulty, which would not directly affect measurement of individual differences.

However, the Rasch model is generally simplification of the real world. In general, I think it takes you a long way in understanding the factors driving test performance. However, in some cases you might have reading items which some individuals understand better than others and this factor is unrelated to ability (e.g., a reading that embodies cultural assumptions shared by only some individuals). It is for this reason that reading comprehension tests should probably avoid content where a subgroup is likely to possess substantially more domain specific knowledge on the topic.


How to structure affective picture stimuli for an EEG study? I want to design an EEG paradigm for passive affective picture viewing. Can I use a block design for three different emotions, where each block represent a particular emotion? Or would a better design randomize all the images of all emotions?

Disclaimer: These are my preferences, biased by my own research experience.

In general, I am not a fan of block designs. Blocking introduces difficulty in comparing both neural and behavioural activity between blocks due to effects of practice, fatigue, adaptation, learning, boredom, muscle tension and possibly others. It is of course possible to counter-balance block order across participants, but then you have to hope that within participants these effects will be roughly of the same magnitude in order to properly cancel out. Since in neuroimaging research we often don't go for large numbers of participants, I tend to prefer event-related designs.

I also sometimes look at signals which are so low in intensity (such as gamma power) that I want to avoid anything that will saturate the signal, and previous trials of the same type do generally saturate it quite a lot, sometimes to the point that I can't see it any more.

However, I also have two reasons for avoiding purely event-related designs. One is that some effects might depend on previous trials. If, for example, people don't react as much to happy stimuli if they're still recovering from the previous angry stimulus, or if they're surprised by the trial change (there's another emotion for you) and you are interested in the happy reaction itself, then you do need blocks... and you also need to discard the first few trials when a block changes. Another reason is that I might be manipulating too many variables in the task and it gets difficult for the study participants. In that case I might decide to manipulate one variable in a block-wise fashion and another in a trial-by-trial fashion. Only you know whether these restrictions apply to your design.

But even if I do go for a block design, I would never* do all the trials in one trial type at once. Instead, I would create mini-blocks, consisting of a small number of trials, for example 10-20. Then I shuffle these mini-blocks randomly per participant, without repetitions. That way you can get all the positive effects from blocking with minimal negative effects.

.* never again, that is.


Can learning be facilitated by transcranial magnetic stimulation? I read a book a while ago called The Brain that Changes Itself by Norman Doidge (2007), and it brought to my attention a machine known as a transcranial magnetic stimulator (TMS) which can noninvasively excite neurons in someone's brain. Doidge mentioned an experiment that used TMS to excite the neurons in patients' pleasure centers, which caused them so much enjoyment that some actually begged the researchers to do it again.

I have also learned about PTSD (posttraumatic stress disorder) and how it happens when overly excited neurons are firing, creating a strong memory.

What if the TMS was made to excite the part of the brain that stores memory (the amygdala I believe) in a fashion similar to PTSD's inadvertently created states, and during the hyper-excited state, the subject was given accurate information to memorize? I specify "accurate" because whatever would be learned or observed in this state would be powerfully etched into memory.

I am not a neuroscientist, so please give answers in layman's terms.

I would like to know if it is possible, what the mechanism would be that would allow us to experience improved learning and what the possible side effects would be.

Reference

Doidge, N. (2007). The brain that changes itself: Stories of personal triumph from the frontiers of brain science.  Official website: http://www.normandoidge.com/normandoidge.com/MAIN.html.

Sadly (or should I be happy that Google is this awesome? Not to mention the rate of scientific progress!), all I really had to do to come up with an answer was perform a Google search for "learning transcranial magnetic stimulation". The first hit, a ScienceDaily page (Ruhr-University Bochum, 2011) page, lists some journal references (Mix, Benali, Eysel, & Funke, 2010; Benali et al., 2011) that effectively say (in laymen's terms), "Yes!" Here's ScienceDaily's summary (I'll let you read the rest at the source):

  What sounds like science fiction is actually possible: thanks to magnetic stimulation, the activity of certain brain nerve cells can be deliberately influenced. What happens in the brain in this context has been unclear up to now. Medical experts have now shown that various stimulus patterns changed the activity of distinct neuronal cell types. In addition, certain stimulus patterns led to rats learning more easily. [Emphasis added.]

To show how hard I'm working to really earn that bounty of yours, here's the summary from the second Google hit, a review article on this very topic (Reis et al., 2008; again, plenty more info at the source):

  In summary, the scarce studies performed so far point to the encouraging conclusion that noninvasive brain stimulation can contribute to the understanding of mechanisms underlying motor learning and motor memory formation and raise the exciting hypothesis that this increased understanding could in the future result in the development of new strategies to enhance specific stages of learning and memory processing in healthy humans and in patients with brain lesions (see chapter by Gerloff et al.). [Gerloff et al. doesn't appear in the references; emphasis added.]

Edit: I see from your comment that you want me to explain the mechanism. Since you offer a bounty, I'll play along and dance for it a bit. Here's another excerpt from Reis and colleagues (2008, page 6 of 16):

  It would be theoretically possible to facilitate motor learning processes in which [the primary motor cortex] is involved by enhancing excitability in the “learning” [primary motor cortex (Pascual–Leone, Valls–Solé, Wassermann, & Hallett, 1994)] or by decreasing excitability in the “resting” [primary motor cortex (Schambra, Sawaki, & Cohen, 2003; Plewnia, Lotze, & Gerloff, 2003)], but see also Wassermann[, Wedegaertner, Ziemann, George, & Chen (1998)]. The intrinsic intracortical mechanisms by which these oversimplified models may operate remain to be identified ([Perez & Cohen, 2008; Daskalakis, Paradiso, Christensen, Fitzgerald, Gunraj, & Chen, 2004; Koch, Franca, Mochizuki, Marconi, Caltagirone, & Rothwell, 2007;] see for discussion chapters by Walsh et al., Di Lazzaro et al., Berardelli et al.). [References unavailable for these three discussion chapters; emphasis added.]

You may want to read the review further for yourself or ask follow-up questions if this is an unsatisfactory explanation of the mechanism.

Since that review was a little hesitant to conclude conclusively, and it's five years old now, I'll also throw in a brand-new bit of original research (Wall et al., 2013) that demonstrates the supportive trend continues:

  Conclusion: These preliminary findings suggest rTMS does not adversely impact neurocognitive functioning in adolescents and may provide subtle enhancement of verbal memory as measured by the CAVLT. Further controlled investigations with larger sample sizes and rigorous trial designs are warranted to confirm and extend these findings. [Emphasis added.]

$\uparrow$ That $\uparrow$ was the fifth Google hit! Also, the seventh (Jelić et al., 2013) says it's not a placebo effect!

Going a little wide, transcranial direct current stimulation (which is somewhat different from magnetic stimulation, though maybe not in ways that concern you) works too (Fields, 2011; Kincses, Antal, Nitsche, Bártfai, & Paulus, 2004; Fregni et al., 2005; Nitsche et al., 2003; Ohn et al., 2008; Flöel, Rösser, Michka, Knecht, & Breitenstein, 2008; Chi & Snyder, 2012)—you can even try it yourself for $249 or £179! I just had to follow a few links from the 14th Google hit (Mims, 2012) to find all that. I'm a little shocked (pardon the pun) at how legit this actually seems...

Edit (by Fizz): Note that a more recent (2017) meta-analysis of tDCS studies found significant problems with their p-curves, making the authors of this meta-analysis conclude that

  Using a p-curve analysis, we found no evidence that the tDCS studies had evidential
  value (33% power or greater), with the estimate of statistical power of these studies being
  approximately 14% for the cognitive studies, and 5% (what would be expected from
  randomly generated data) for the working memory studies.

Also (16th Google hit), it looks like the U.S. National Institutes of Health Clinical Center is currently recruiting participants for their study, "The Effect of Transcranial Magnetic Stimulation on Learning With Reward in Healthy Humans", so maybe you could even get Uncle Sam to pay you (for testing magnetic, not electrical stimulation)! However, if I'm reading that right, it's a study of learning disruption, which is another potential (and maybe not-so-desirable) application of TMS, according to the 18th hit (De Weerd et al., 2012).

Edit: Reis and colleagues (2008) also review this disruptive process somewhat; I get the impression that disruption is much easier than enhancement to achieve with magnetic stimulation (not sure whether this applies to direct electrical current as well). It seems TMS has been used mostly to knock out brain function temporarily in localized areas to simulate the effects of brain lesions. Use of TMS to enhance excitability rather than inhibit it seems to be the more recent innovation, and maybe a separable effect (i.e., it may be possible to excite the brain using TMS without causing inhibition).

In anticipation of the next question, "Is it safe?" I feel I should add that this is definitely not my area of expertise – I got a B- in biopsych as an undergrad – so again, I'll let the experts speak for themselves (Poreisz, Boros, Antal, & Paulus, 2007), but as a fan of dystopian sci-fi, I will at least say that the short-term dangers seem like they could've been much worse! Same for the ethical ramifications, more or less (Hamilton, Messing, & Chatterjee, 2011). It's reassuring to see so much thought going into this already; I might otherwise be worried about how far behind the times we seem to be here! BTW, these last revelations come thanks in part to the 33rd Google hit (Oremus, 2013). I'm afraid no amount of tDCS will allow us to keep up with Google...

P.S. From what I've seen in skimming some of these, it doesn't have anything in particular to do with the limbic system (which includes the amygdala). I saw a brief explanation suggesting it affects myelination, which is basically the process by which the brain speeds up electrical signal transmission. Myelin is a sort of segmented coating for the axons of neurons, which can be quite long individually. Myelin allows electrical signals (action potentials) to jump across myelinated segments quickly, rather than propagating relatively slowly across every millimeter in the normal fashion. I also saw some indication that transcranial electromagnetic (didn't note which) stimulation might speed up other aspects of neural construction, such as the rate at which connections form (not just the rate at which they upgrade from the neural equivalents of a dial-up modem to fiber-optic).

References

Benali, A., Trippe, J., Weiler, E., Mix, A., Petrasch–Parwez, E., Girzalsky, W., ... & Funke, K. (2011). Theta-burst transcranial magnetic stimulation alters cortical inhibition. The Journal of Neuroscience, 31(4), 1193–1203.
Boggio, P. S., Ferrucci, R., Rigonatti, S. P., Covre, P., Nitsche, M., Pascual–Leone, A., & Fregni, F. (2006). Effects of transcranial direct current stimulation on working memory in patients with Parkinson's disease. Journal of the Neurological Sciences, 249(1), 31–38. Retrieved from http://www.tmslab.org/publications/154.pdf.
Chi, R. P., & Snyder, A. W. (2012). Brain stimulation enables the solution of an inherently difficult problem. Neuroscience Letters, 515(2), 121–124. Retrieved from http://ingienous.com/wp-content/uploads/2012/05/snyder-9-dots-paper.pdf.
Daskalakis, Z. J., Paradiso, G. O., Christensen, B. K., Fitzgerald, Gunraj, & Chen. (2004). Exploring the connectivity between the cerebellum and motor cortex in humans. Journal of Physiology, 557, 689–700. Retrieved from http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1665103/.
De Weerd, P., Reithler, J., van de Ven, V., Been, M., Jacobs, C., & Sack, A. T. (2012). Posttraining transcranial magnetic stimulation of striate cortex disrupts consolidation early in visual skill learning. The Journal of Neuroscience, 32(6), 1981–1988. Retrieved from http://www.jneurosci.org/content/32/6/1981.long.
Fields, R. D. (2011, November 25). Amping up brain function: Transcranial stimulation shows promise in speeding up learning. Scientific American: Mind & Brain. Retrieved from http://www.scientificamerican.com/article/amping-up-brain-function/.
Flöel, A., Rösser, N., Michka, O., Knecht, S., & Breitenstein, C. (2008). Noninvasive brain stimulation improves language learning. Journal of Cognitive Neuroscience, 20(8), 1415–1422. Retrieved from http://www.researchgate.net/publication/5548486_Noninvasive_brain_stimulation_improves_language_learning/file/5046351db1c615613a.pdf.
Fregni, F., Boggio, P. S., Nitsche, M., Bermpohl, F., Antal, A., Feredoes, E., ... & Pascual–Leone, A. (2005). Anodal transcranial direct current stimulation of prefrontal cortex enhances working memory. Experimental Brain Research, 166(1), 23–30. Retrieved from http://www.researchgate.net/publication/7745540_Anodal_transcranial_direct_current_stimulation_of_prefrontal_cortex_enhances_working_memory/file/9fcfd50a3483033595.pdf.
Hamilton, R., Messing, S., & Chatterjee, A. (2011). Rethinking the thinking cap Ethics of neural enhancement using noninvasive brain stimulation. Neurology, 76(2), 187–193. Retrieved from http://wernicke.ccn.upenn.edu/~chatterjee/anjan_pdfs/Neurology_2011_HamiltonMessing_Chatterjee.pdf.
Jelić, M. B., Stevanović, V. B., Milanović, S. D., Ljubisavljević, M. R., & Filipović, S. R. (2013). Transcranial magnetic stimulation has no placebo effect on motor learning. Clinical Neurophysiology, 124(8). 1646–1651.
Kincses, T. Z., Antal, A., Nitsche, M. A., Bártfai, O., & Paulus, W. (2004). Facilitation of probabilistic classification learning by transcranial direct current stimulation of the prefrontal cortex in the human. Neuropsychologia, 42(1), 113–117. Retrieved from http://www.researchgate.net/publication/9011312_Facilitation_of_probabilistic_classification_learning_by_transcranial_direct_current_stimulation_of_the_prefrontal_cortex_in_the_human/file/d912f50597d44df446.pdf.
Koch, G., Franca, M., Mochizuki, H., Marconi, Caltagirone, & Rothwell. (2007). Interactions between pairs of transcranial magnetic stimuli over the human left dorsal premotor cortex differ from those seen in primary motor cortex. Journal of Physiology, 578, 551–562. Retrieved from http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2075160/.
Mims, C. (2012, March 8). DIY kit overclocks your brain with direct current. Technology Review: View. Retrieved from http://www.technologyreview.com/view/427177/diy-kit-overclocks-your-brain-with-direct-current/.
Mix, A., Benali, A., Eysel, U. T., & Funke, K. (2010). Continuous and intermittent transcranial magnetic theta burst stimulation modify tactile learning performance and cortical protein expression in the rat differently. European Journal of Neuroscience, 32(9), 1575–1586.
Nitsche, M. A., Schauenburg, A., Lang, N., Liebetanz, D., Exner, C., Paulus, W., & Tergau, F. (2003). Facilitation of implicit motor learning by weak transcranial direct current stimulation of the primary motor cortex in the human. Journal of Cognitive Neuroscience, 15(4), 619–626. Retrieved from http://www.researchgate.net/publication/10710628_Facilitation_of_implicit_motor_learning_by_weak_transcranial_direct_current_stimulation_of_the_primary_motor_cortex_in_the_human/file/79e4150ae2024da0f0.pdf.
Ohn, S. H., Park, C. I., Yoo, W. K., Ko, M. H., Choi, K. P., Kim, G. M., ... & Kim, Y. H. (2008). Time-dependent effect of transcranial direct current stimulation on the enhancement of working memory. Neuroreport, 19(1), 43–47. Retrieved from http://diyhpl.us/~bryan/papers2/neuro/Time-dependent%20effect%20of%20transcranial%20direct%20current%20stimulation%20on%20the%20enhancement%20of%20working%20memory.pdf.
Oremus, W. (2013, April 1). Spark of genius. Slate: Technology: Superman. Retrieved from http://www.slate.com/articles/technology/superman/2013/04/tdcs_and_rtms_is_brain_stimulation_safe_and_effective.html.
Pascual–Leone, A., Valls–Solé, J., Wassermann, E. M., & Hallett, M. (1994). Responses to rapid-rate transcranial magnetic stimulation of the human motor cortex. Brain. 117(4), 847–858.
Perez, M. A., & Cohen, L. G. (in press as cited in Reis et al., 2008). Mechanisms underlying functional changes in the primary motor cortex ipsilateral to an active hand. Journal of Neuroscience.
Plewnia, C., Lotze, M., & Gerloff, C. (2003). Disinhibition of the contralateral motor cortex by low-frequency rTMS. Neuroreport, 14, 609–612.
Poreisz, C., Boros, K., Antal, A., & Paulus, W. (2007). Safety aspects of transcranial direct current stimulation concerning healthy subjects and patients. Brain Research Bulletin, 72(4), 208–214. Retrieved from http://www.researchgate.net/publication/6377248_Safety_aspects_of_transcranial_direct_current_stimulation_concerning_healthy_subjects_and_patients/file/9fcfd50a34830ccb05.pdf.
Reis, J., Robertson, E. M., Krakauer, J. W., Rothwell, J., Marshall, L., Gerloff, C., ... & Cohen, L. G. (2008). Consensus: Can transcranial direct current stimulation and transcranial magnetic stimulation enhance motor learning and memory formation?. Brain Stimulation, 1(4), 363–369. Retrieved from http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2621080/.
Ruhr-University Bochum. (2011, January 29). Learn more quickly by transcranial magnetic brain stimulation, study in rats suggests. ScienceDaily. Retrieved February 10, 2014 from http://www.sciencedaily.com/releases/2011/01/110128121629.htm.
Schambra, H. M., Sawaki, L., & Cohen, L. G. (2003). Modulation of excitability of human motor cortex (M1) by 1 Hz transcranial magnetic stimulation of the contralateral M1. Clinical Neurophysiology, 114, 130–133.
Wall, C. A., Croarkin, P. E., McClintock, S. M., Murphy, L. L., Bandel, L. A., Sim, L. A., & Sampson, S. M. (2013). Neurocognitive effects of repetitive transcranial magnetic stimulation in adolescents with major depressive disorder. Frontiers in Psychiatry, 4(165). Retrieved from http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3859914/.
Wassermann, E. M., Wedegaertner, F. R., Ziemann, U., et al. (1998). Crossed reduction of human motor cortex excitability by 1-Hz transcranial magnetic stimulation. Neuroscience Letters, 250, 141–144.


Does Stroop test performance correlate with any personal characteristics or abilities? Have there been any studies that found that an extremely high (or low) Stroop test score correlates with certain personal characteristics, abilities or aptitudes, or would all such conclusions be outside the test's scope?

N.B.: There are many varieties of "Stroop-like" tasks, which as a class are often called implicit association tests or IATs.  Since those are likely to test attributes related to their specific construction, I have excluded them from this answer.

There have been a variety of papers studying correlations of Stroop performance with other characteristics.

Ward et al. (2001) examined the correlation between Stroop effects and executive control, finding that Stroop costs and other measures of executive control were not well correlated.

Brewer et al. (2008) found sizable correlations between neural activation in Stroop testing and treatment outcomes among cocaine-dependent patients; they interpret this to suggest executive control differences are determinative in treatment outcome, but this interpretation is contradicted by Ward et al. above.

Less recently, Golden (1975) found the Stroop test to correlate with measures of creativity; I have found no more recent discussion of this so cannot speak to its currency.

References
Ward, G., Roberts, M., & Phillips, L. (2001). Task-switching costs, Stroop-costs, and executive control: A correlational study. The Quarterly Journal of Experimental Psychology Section A: Human Experimental Psychology Volume 54, Issue 2, pages 491-511. DOI:10.1080/713755967

Brewer, J., et al. (2008). Pretreatment Brain Activation During Stroop Task Is Associated with Outcomes in Cocaine-Dependent Patients. Biological Psychiatry Volume 64, Issue 11, 1 December 2008, Pages 998–1004. doi:10.1016/j.biopsych.2008.05.024

Golden, C. (1975). The Measurement of Creativity by the Stroop Color and Word Test. Journal of Personality Assessment. Journal of Personality Assessment Volume 39, Issue 5, 1975 pages 502-506. DOI: 10.1207/s15327752jpa3905_9


Cognition of people born by C-section vs born ordinarily? Has there been any research comparing the cognition of people born via C-section to people born vaginally?

During a vaginal birth, the baby's head is pressured and deforms somewhat in order to make it through. Hypothetically, this could cause some minor brain damage which would be avoided by C-section birth.

I don't know if there has been any research on this, but there is reason to doubt that such research would yield any meaningful results.

You would need to control for a large number of things to address your question. For example, people born by C-section are people who have access to medical care. Those people have money, which is associated with education and opportunities, both of which are associated with IQ.

Additionally, a C-section is medical intervention for when something goes wrong. The things that lead to C-sections (such as improper positioning of the baby before birth, compromising oxygen supply) can lead to brain damage. C-sections generally are associated with many more complications than healthy vaginal births.

Another thing to consider is that vaginal birth would be a poor evolutionary solution for human reproduction if it lead to significantly lower intelligence.

I would be much less surprised if the opposite of your hypothesis turned out to be true.


what is the reptile brain? As a Carl Sagan fan, I remember (in Cosmos TV shoe) "territoriality, aggression and ritual" are products of the reptile brain while higher-level stuff like loyalty, planning for future are mammalian, which implies different brain regions for each functions.

Even Sheldon Cooper has something to say about this:

  Penny’s emotional responses originate from the primitive portion of
  the brain known as the Amygdala, while speech is centred in the much
  more recently developed Neocortex. The former can easily overpower
  the latter giving scientific credence to the notion of being rendered
  speechless.

And said by on-screen and off-screen neuroscientist and science consultant Mayim Bialik:

  So says your prefrontal cortex. But meanwhile, the limbic system of
  your brain is calculating that if another woman is attracted to
  Leonard, it must be because he’s desirable.

It implies that the brain is composed of three parts, with vast differences in development, can overpower each other and process stimuli independently.

What exactly is the reptile brain and do modern theories prove such a concept?

The reptilian brain is the oldest part of the triune brain. And the triune brain is a unified account of brain function and brain evolution.

The story goes like this. The brain can be divided into three sections:

The reptilian brain, named so because it encompasses structures that did not change much from reptile to man. It includes the basal ganglia and cerebellum, and controls pretty much everything that a reptile can do: breathing, walking, appetite, sensation, simple motor reactions to the environment, etc.
The mammalian brain (sometimes called paleomammalian), which encompasses structures that are unique to mammals but similar across mammalian species. These structures belong to the limbic system and are dedicated to processing emotion and memory. Anything your cat can do, should be either in the reptilian or the mammalian brain. Anything it can't do, is in the third part of the triune brain.
The neocortex, found in primates, which is involved in higher order functions such as language.

Now, this is an oversimplification both structurally and functionally. For example, birds don't fit this theory very well because they don't have much of a limbic system, but do have some impressive problem solving skills. And functionally, these functions are interrelated in man, who can, for example, experience moral disgust which bridges higher-order and emotional functions. This is why the triune brain is the kind of thing you would find in an undergraduate psychology textbook, but it's not the kind of thing neuroscientists talk about among themselves.


Failing to recognise one's own work Disclaimer:
This is not a self help question, I am using myself as an example to illustrate my question.

Example:

I have posted many questions and answers on this site within a relatively short time. Frequently (and with my blessing) our Mod Jeromy will edit my question titles. He does not edit all of the titles.

I find myself browsing through the site, looking to upvote older questions, looking for unanswered questions. Sometimes (and too often) I come across a question and think, that's interesting, only to realise I posted the question. I do this with answers also. I think that's interesting and see I've posted it.

I can surmise, it is because of the sheer volume, perhaps stress and the inability to process memory.  I am wondering if this is a known condition.

Question:

What causes this phenomena of failing to recognise one's own work?
Is it a recognised condition?
Which part of our brain is responsible for this?

I'm using your example, because another example would lead to a different interpretation. Using your example is not meant to help you, just to illustrate my answer.

The normal situation is to forget things. There are people who dispute this, believing that you store any and all information you ever encountered (after all, what would the famous 90% unused brain be for?), but from a more scientific perspective, most of the info that goes into your sensorium is simply lost after it was used. Because you don't need to remember the color of the car that just passed.

So the question is, why and when do we actually store stuff in our memories? Short answer: when it appears important. Usually, because it is connected to an emotion. If you care about something, you remember it, if you don't, you won't. This does not mean that you only forget stuff that is unimportant, though. If you are stressed or distracted, important things are momentarily unimportant.

Interpreting your example from this perspective, we could infer that you did not much care about those questions you wrote, at least not individually, because you asked them for other purposes (passing the time, gaining reputation, socializing in a community), or that you have other more important stuff going on in your life and that you ask questions here as a distraction, while part of your mind is still elsewhere.

But then, there is another phenomenon: If you have a thought and want to remember it, it blocks your mind. I'm sure you have noticed how trying not to forget the great sentence that you want to begin your next novel with keeps you from having any other ideas. That's why writers carry notebooks: they jot down the sentence, and immediately forget it, freeing their minds to new ideas.

So when you write your question here, you are actually telling your mind: "Okay, that's done, now let's think of something else." And your mind complies, discards that idea, and starts thinking of other things, forgetting any former thoughts.


How does the brain break down visual information for processing? What "channels" is visual input broken into? Some time ago I remember reading about how the human brain breaks down visual information into a number of individual "channels".

For example, one channel might focus on edges and lines, another might focus on being a contrast map, while another provide a color information overlay. Each "channel" being a much more simplified part of the entire visual input.

From what I understood, modern research into the visual cortex has provided some insight into what the channels might be and how they're broken down. If my understanding of current research is correct I was hoping to find some more detailed information explaining how the visual information is broken down and processed (articles at the technical level of Scientific American are fine, so long as they detail the types of "channels" present).

My desired take-away from this is to brainstorm ideas for how I might better pre-process an image into feature data for a standard neural network learning algorithm, based on the human experience.

The human visual processing system receives input from the eyes, and then passes it through a number of areas of the brain that break it down, process it in various different ways, recombine it, and break it down again several times.  I'm assuming this question is only about the visual cortex, general theories about how information might be broken down for processing there, and only concerning parallel-processing (channels), as opposed to sequential specialization (layers), otherwise the answer should fill up a textbook.

Main pathways through visual cortex:

The traditional understanding of the visual cortex divides it into 2 main pathways:

  Each V1 transmits information to two primary pathways, called the
  ventral stream and the dorsal stream.

  The ventral stream begins with V1, goes through visual area V2, then through visual area V4, and to the inferior temporal cortex (IP
  cortex). The ventral stream, sometimes called the "What Pathway", is
  associated with form recognition and object representation. It is also
  associated with storage of long-term memory.
  The dorsal stream begins with V1, goes through Visual area V2, then to the dorsomedial area (DM/ V6) and Visual area MT (middle
  temporal/ V5) and to the posterior parietal cortex. The dorsal stream,
  sometimes called the "Where Pathway" or "How Pathway", is associated
  with motion, representation of object locations, and control of the
  eyes and arms, especially when visual information is used to guide
  saccades or reaching.

The "what" and "where" pathways are also sometimes referred to as the "perception" and "action" pathways, respectively.

Another common theory about the visual cortex identifies at least 3 modules: Motion, colour, and form.  Evidence for these proposed modules comes largely from lesion studies and related disorders of the visual system.  In general, an impairment in one module doesn't seem to affect the others, suggesting that these specializations are processed independently and in parallel.  However, it is not clear if they form distinct pathways through the visual cortex.

There is also evidence for a long-term memory pathway (visual-perirhinal-hippocampal stream) that feeds memory information from and to the visual cortex.  Many other pathways have been postulated; this field of research is very active, consensus on further detail remains elusive for now.

Complications to such models:

Such "pathway" models of the visual cortex are limited by a number of factors:

There is evidence of significant interaction between the streams
There is evidence of feedback cycles within the streams
Evidence that different pathways are used in different situations
There is some evidence of asymmetric processing in the brain
There is also some evidence of inter-person differences

Furthermore, as mentioned, the visual cortex is only part of the visual system.  Significant processing happens earlier - you mentioned about edge detection, some of that appears to already be happening by the time signals reach the visual cortex.  And more processing happens later as well, in the parietal and temporal cortices for example, such as facial recognition.

Implications for artificial neural networks:

The visual cortex may not be ideal inspiration for ANNs, especially since it only handles a not-very-early part of the process, such that the signals it receives have already undergone significant modification from the raw stimuli.  Additionally, its pathway structure is fairly complex, and not fully understood.  There have nonetheless been attempts to simulate parts of the visual cortex and compare to non-biologically inspired networks.

The LGN - an area of the brain involved earlier in the process - may be more amenable to some inspiration and simulation, as it is a simpler structure with clearer functions and pathways.  It handles some of the functions you described at a more basic level, including some edge detection, colour processing, contrast, and various other aspects of perception such as depth, brightness, and movement, albeit with many of the same caveats as mentioned for the visual cortex.