Feeds:
Posts
Comments

Archive for the ‘Behavioural Psychology’ Category

brainpower_big.jpg The “racial intelligence” bulldozer that James Watson set rolling a couple of weeks back is still whirring in our backyards as the new row over superior Jewish IQ scores is begging media attention.

This time the perpetrator is the Bell Curve fame Charles Murray and his American Enterprise Institute. I am not going into much detail about it. You can read the whole thing here.

The book ‘Bell Curve’ by Charles Murray and Richard J. Herrnstein once had the fate of being the most celebrated and at the same time, the most shunned book dealing with sociology of intelligence. The book set the scene for serious debates on the way IQ tests were used as real measurements of peoples’ intelligence.
The consensus regarding the average intelligence of various races was popularized to be as follows: Ashkenazim Jews 115; East Asians 105; Whites 100; American Indians and most Hispanics 90; African Americans 85; and sub-Saharan Africans 70. By the same order, accumulation of wealth, the level of income, achieved academic success etc., were also popularized to follow closely with the average IQs of these six racial groupings.

What do we actually know about Intelligence Quotient?

The results of large studies and their meta-analyses can be filtered down to the following concrete points:

  • IQ tests aspire to assess only 4 areas of human intelligence:

Verbal comprehension, Processing Speed, Working (arithmetic) memory and Perceptual organization (visuo-spacial).

  • People who are good at one area of intelligence (defined by the test) tend to be good at other areas too (+ve correlation).
  • IQ tests are always constrained by the cultural, linguistic, socio-economic and other contextual biases.
  • IQ tests don’t assess attributes like

Creativity, Personality, Practical sense, Social sensitivity, Leadership and Altruism.

  • IQ tests can be consistently and precisely interpreted only when the scores are very low or very high.
  • General Intelligence or ‘g’, as measured by IQ scores, is an attribute of the psyche (the software), rather than any macroscopic characteristic of the brain (the hardware).
  • IQ test scores are positively correlated to genetic make up as evident from large twin studies.
  • The effects on IQ scores thought to be caused by the environmental factors tend to disappear as the test-takers enter adulthood and further into old age.
  • Even then, there is no definitive evidence yet to link higher IQ test scores to brain size, or any particular genotype.
  • Training for IQ tests can certainly improve IQ scores.

Genetic basis for intelligence

The animal Brain plays the role of just the hardware on which the software called “mind” runs. Stretching that metaphor a little points out that there need not be a one-to-one correspondence between the hardware and the software for every behavioral trait. And studies have only shown IQ to be genetically linked; they have NOT shown that intelligence is solely a genetic quality. Having the right environment is extremely essential for the full expression of such “intelligence” genes (if there are any).
The examples of higher average IQ scores in certain human races may hence be more cultural rather than biological. Cultures that pressurize their children to achieve more in academics tend to produce better IQ scores. Just like average human height has increased over generations due to better nutrition, expression of intelligence too can hopefully improve in encouraging environs.

Is intelligence an essential survival quality?

It may be difficult to swallow without salt but it’s true: Intelligence does not confer any significant evolutionary survival advantage to any species.

Survival in the natural world, in a reductionistic sense means advantage in numbers, disease-free & adaptable gene pool and flexibility with nature. Social achievement and academic profiles, which are direct correlates of high IQ scores, have nothing to do with gene propagation and adaptability, even though various human races emphasize on these aspects more and more after every generation.

If we extrapolate the selfish gene concept to the macro evolutionary scenario, we find that the mind, consciousness, intelligence and all the emergent behavioral patterns are just a few of the myriad ways of “selfish” genes to propagate themselves.

This “rule” becomes clearer when one steps further backwards and look at the picture of evolution of life on planet earth as a whole.

iq-cartoon.jpg


Advertisements

Read Full Post »

Sex differences in cognition and behavior–such as increased aggression in males–are usually thought to involve hormones, which can “masculinize” or “feminize” a brain temporarily or permanently. But now, a mouse study shows that some sex-linked genes don’t need hormones to shape male and female behavior.

 

The Y chromosome in males have been identified to contain the gene SRY (Sex determining Region Y ) that determines the formation of testicles long back, and by early ’90s scientists had learned how to breed mice whose genes and hormones function independently. Since human SRY is similar to SRY of mice, a model of SRY function has been developed in mice.

By knocking out the testes-determining SRY gene, on the Y chromosome, researchers made XY mice that churn out estrogen; and by adding SRY to females, they produce XX mice that manufacture male hormones.

With the help of such mice, it was shown that genes unrelated to hormone production also played an independent role in aggression and nurturing behaviors. This was a new revelation because, until then it was believed that only the hormones determined such behaviours.

A team led by neuroscientist Jane Taylor of Yale University was interested in habit-forming behaviors in which gender differences also have been documented. She and her colleagues trained these mice, as well as normal male and female mice, to poke their noses through one of three holes in order to obtain a food pellet. Then, some of the mice were subjected to “conditioned taste aversion”. After eating the food, they were injected with a chemical that made them sick (something like what we use in alcoholic patients to help them quit drinking.) Ordinarily, mice will quickly learn to avoid the food, but they will still eat it if they have developed an automatic habit. That happened more often for the XX mice regardless of whether they produced male or female hormones.Thus, they say, the sex difference must have something to do with genes that are not involved in the production of sex hormones.

Neurobiologist Lawrence Cahill of the University of California, Irvine, says that the study “relates very well to established sex differences in the acquisition of addictive habits.” For example, women progress from casual drug-taking to a drug habit faster than men do–a phenomenon some have attributed to hormones. Taylor says that the work also implies that women can be good multitaskers–by quickly forming habits that leave their higher brain functions free for other chores.

Blogger’s Post Script: The last piece about the study implying that women can be good multitaskers seems to be a hasty extrapolation to me, as the quoted study doesn’t provide results of any of that sort, although estrogen has been linked to many skilled activities and greater attention span. It is also important to keep in mind that the precise mechanisms of sex differentiation are still unknown and that gender differentiation is accomplished through a cascade of gene activations. Further factors are involved, then, before as well as after the SRY expression – for example the WT-1, SF-1, DAX-1, SOX-9 genes. (I’m not being chauvinistic here – just bringing to notice a bad practice in science reporting, that’s all.)

Report in Nature Neuroscience. (21 October).

News modified from Sciencenow.

Read Full Post »

A recently published Florida State University study is pointing at the evolutionary psychology of attractive faces.

The paper, “Can’t Take My Eyes Off You: Attentional Adhesion to Mates and Rivals,” by Jon Maner, an assistant professor of psychology at FSU, is one of the first to show how strongly, quickly and automatically we are attuned to attractive people, he said. FSU graduate students Matthew Gailliot, D. Aaron Rouby and Saul Miller co-authored the study.

In a series of three experiments, Maner and his colleagues found that the study participants, all heterosexual men and women, fixated on highly attractive people within the first half of a second of seeing them. Single folks ogled the opposite sex, of course, but those in committed relationships also checked people out, with one major difference: They were more interested in beautiful people of the same sex.

If we’re interested in finding a mate, our attention gets quickly and automatically stuck on attractive members of the opposite sex, but if we’re jealous and worried about our partner cheating on us, attention gets quickly and automatically stuck on attractive people of our own sex because they are our competitors.” Maner said

Maner’s research is based on the idea that, through processes of biological evolution, our brains have been designed to strongly and automatically latch on to signs of physical attractiveness in others in order to both find a mate and guard him or her from potential competitors.

“These kinds of attentional biases can occur completely outside of our conscious awareness,” he said.

The insecurities of romance ?

Biology or not, this phenomenon is fraught with potential romantic peril. For example, even some people in committed relationships had difficulty pulling their attention away from images of attractive people of the opposite sex. And fixating on images of perceived romantic rivals could contribute to feelings of insecurity.!

Modern technology has enhanced these pitfalls. Although there are people of striking beauty in real life, singer Frankie Valli’s pronouncement that “you’re just too good to be true” may be the case when it comes to images in movies and magazines or on the Internet.

“It may be helpful to try to minimize our exposure to these images that have probably been ‘doctored,’” Maner said. “We should pay attention to all of the regular-looking people out in the world so that we have an appropriate standard of physical beauty. This is important because too much attention to ultra-attractive people can damage self-esteem as well as satisfaction with a current romantic partner.”

“Women paid just as much attention to men as men did to women,” he said. “I was also surprised that jealous men paid so much attention to attractive men. Men tend to worry more about other men being more dominant, funny or charismatic than they are. But when it comes to concerns about infidelity, men are very attentive to highly attractive guys because presumably their wives or girlfriends may be too” Maner said.

sources: FSU news room; http://content.apa.org/journals/psp

Read Full Post »

The sudden feeling of vague familiarity about certain scenes or things of life is a common phenomenon we might all have experienced one time or the other. Many of them were dream-like experiences, while some were so vivid; we almost thought it was a replay of the past.

The term “déjà vu” is believed to have been used first in 1876 by French physician Émile Boirac. Each episode last a few seconds only and is much common for Younger people to have these dream-states more often than older adults, yet people of all ages experience déjà vu, especially when they are stressed. There is a reverse of déjà vu, called jamais vu. Here, a familiar person or place is rejected as having never seen before.Many mysteries cloud this curious play of brain chemistry and many of them give rise to beliefs in rebirth, telepathy and clairvoyance. But is this strange feeling of familiarity really a message traveling thru time and space, from the light cone of our past? Or is it just some unconsciously managed memory trace that is peeking up at a second stimulus thru the same neural pathway?

Science has been tracking this question for many years but the stumbling block in investigating the phenomenon is the problem of recreating it in labs.

The Freudian psychoanalysts call déjà vu a replay of suppressed memories. They call it paramnesia. The original event was somehow linked to distress and was being suppressed from conscious recognition, no longer accessible to memory, they say. Temporal lobe epilepsy patients have been thought as good candidates, but their memories lack the true quality of déjà vu – the subject’s disbelief in the memory!

Dr. Vernon M. Neppe[/b] , the Director of the Pacific Neuropsychiatry Institute in Seattle, empirically defined the term déjà vu as: [u]

“any subjectively inappropriate impression of familiarity of a present experience with an undefined past.”[/u]

(His book titled [i]The psychology of Déjà vu: Have I been here before?[/i] has detailed out a long list of déjà vu presentations long back in the 1980s.)

In déjà vu, the subjective feeling of “replay of past” is imminently followed by a feeling of disbelief and rejection of the memory trace, as is widely documented. The act of seeing or hearing also does evoke a feeling of familiarity. It doesn’t pertain just to the memory alone. These qualities are absent in epileptic patients’ recollections and in drug-induced hallucinations. In such cases, the patient or the subject strongly “believes” in these traces of replayed “memory”. A similar phenomenon is seen in schizophrenics too (‘false recognition’). Hence many scientists believe that there should be a “non-epileptic” theory for deja vu that will encompass al the attributes of the phenomenon.

 

New light on an old problem

Robert Efron, in 1963 suggested the delayed vision theory. He stated that it is possible that sometimes the blending of information into the temporal lobe might not synchronize well and this may result in the deja vu episodes. Words flashed too rapidly to subjects without giving time for the conscious brain to register them were later identified as familiar by the same subjects in the pioneering experiments of Dr. Larry Jacoby in 1989. Recent simulated studies on attention and priming for attention have brought out certain correlations between gaps in attention and feelings of familiarity as in déjà vu. There are also reliable correlations between déjà vu and stress/fatigue as well as mood swings. It seems that whereas déjà vu may be triggered during times of peak tension when one is overly alert, it may be even more likely when one becomes tired and attention starts to wane. Alan Brown of the Southern Methodist Univ and Elizabeth Marsh at Duke University, ran a few tests on a group of students; based on the idea that deja vu’s originate in subliminal suggestion. They support the the diverted attention theory.

According to the theory, people sometimes see things twice in quick succession: the first time superficially or peripherally; the second time with full awareness. You might glance at a building while talking on a cell phone, for instance, and not really register it, then give it a second look a little while later after you get off the phone. You might not remember the first glance, but your brain has registered it subliminally, so the second glance may seem oddly familiar (see Dr.Brown’s new book [i]The Déjà Vu Experience[/i])

Temporal lobe – seat of Deja vu

Open brain surgery stimulations of déjà vu in temporal lobe has been done from the time of Dr. Penfield the latest being that of Dr.Bancaud.These expositions are being investigated with greater fervor, ever since the Alison R. Preston and John D.E. Gabrieli paper on the role of hippocampus as a scrap book of the brain, has come out.

….the relational/familiarity distinction predicts that patients with focal hippocampal damage would be selectively or disproportionately impaired on associative recognition, but exhibit intact or less impaired performance on single-item recognition. However, patients with selective hippocampal damage were equally impaired on the single-item and associative recognition tasks….. results suggest that the hippocampal formation contributes similarly to declarative memory tasks that require relational or familiarity processing…. the para-hippocampal gyrus differentiates between familiar and unfamiliar stimuli – and does so without having to retrieve a concrete episode from our memories.

The excitement is inexplicable, as the research has opened new ways to understand how we create a world of our own around us rather than fit ourselves into the world around. And that’s were evolutionary psychology starts taking up the issue.

 

Read Full Post »

We have always referred to people with exceptional abilities as “smart”, “clever” or “bright”. By doing so, we unconsciously recognize the existence of a number of different intelligence-subtypes. It has now become a commonsense notion that there exist certain types of intelligence like “arithmetic” intelligence, an “artistic” intelligence, a “commonsense” intelligence, a “cognitive” intelligence, “semantic” (vocabulary based) intelligence or “knowledge based” intelligence.

 

Such a categorization is rooted in our concept that a person who is good at one specific area should necessarily be deficient in another area. For example there are examples around us, of exceptionally brilliant scientist who are absent-minded or super mathematicians who can hardly learn a new language etc.

So how far is this notion true…?

 

Well, scientifically speaking, this notion is partly correct and partly wrong. The analysis of data from more than 400 classic databases on human intelligence research has brought to light three important findings about this:

 

a) People good at one area of intelligence tend to be good at all other areas generally!
b) Intelligence can be an expression of certain pools of interrelated abilities.
c) Though people have a tendency to be “generally intelligent”, there are sufficient evidences for specific types of intelligences and people who are good in such areas.

 

Let us examine each. Point (a) suggests that there is definitely something called “general” intelligence…some specific property of the brain that makes you “clever” on the whole.

 

What is this property of the brain ?

Extensive research into factors like “brain size”, electrical activity, its efficiency in processing visual data, and reaction time to various challenges have shown that people with higher intelligence have faster decision and response times. Such tests have concluded that intelligence correlates well with “speed of processing information”. It is curious to note that though this is the case, we don’t yet have a consensus on how exactly we‘re gonna test this “speed”!
Point (a) also suggests that our intuition about “clever” people being adept at one thing and inept at another is not exactly true.
Though there are sharply defined pools of intellectual abilities, in reality, a clever person can possess varying degrees of all these abilities. But there are compelling evidences of patients called “idiot savants” in neurology that are exceptions to this rule. These patients are a result of a phenomenon called “ Paradoxical functional facilitation”. This means that some brain related hindrances or injuries can result not only in loss or suppression of particular functions but also the enhancement of certain other abilities.
Idiot savants generally have the IQ of a 5 year old or a 10 year old child but may exhibit amazing capabilities in other areas like Calculations or Artistic works, or music.
A famous example is that of Nadia, an “autistic savant” patient who could draw more life-like illustrations than even DaVinci at the age of 8. There are similar people who can retain thousands of pages of Shakespearian literature, but can’t even find their way home after an evening walk. The theory behind this is that the birth injuries caused to their brains enhance the expansion and development of certain other unexpected areas.

Point (b) supports the “savant” theory to some extent. There are indeed inter related pools of certain intelligences, which are outlined as below.


  • Verbal Comprehension pool: consists of abilities involvingVocabulary, similarities, information processing & comprehension
  • Perceptual organization: includes abilities like completing patterns, picture sequencing, block designs and matrix reasoning.
  • Working memory: comprises faculties like digit span, letter-number sequencing, and arithmetic intelligence.
  • Processing speed: constituted by abilities like symbol search and digit-symbol decoding.


All these capacities exhibited in intelligence tests can be conveniently categorized into 8 chief mental faculties, viz.

  1. Visual perception
  2. Auditory perception
  3. Fluid intelligence
  4. Retrieval ability
  5. Crystallized intelligence
  6. Cognitive speediness
  7. General memory and learning
  8. Processing speed


In 1988, Snyderman and Rothman brought out a book on IQ controversies. They published the results of an opinion poll conducted among the specialists in cognitive psychology and allied fields.

About 99% opined that the major element of intelligence was “Abstract Thinking”. The “Ability to Solve Problems” was chosen by ~97%. And 96% of the experts considered intelligence as a product of the “Capacity to Acquire Knowledge” too. But curious enough, only 80% chose Memory as a component. Cognitive speediness was considered by 71% and General knowledge by 62%.
Still strange was the case of Creativity: hardly 60% chose this aspect as an important constituent of intelligence!!
Research data run parallel to this poll result…but we shouldn’t forsake the fact that some of the most successful scientific theories in mankind’s history were born out of sheer creativity. Examples include General Relativity, parts of QED, photonics, Planck’s theories…

   

Read Full Post »