Archive for the ‘Brainscapes’ 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.



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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.


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Epileptic seizures have always been at the center of attraction for all who study about spiritual emotions. Epilepsy is caused by a kind of misfiring that occurs untimely in a set of neurons in ones brain. Any part of the brain can go berserk like that, but most commonly the Temporal lobes (that part of brain that is close to your ears on both sides) are the seat of such misfiring. This results in stimulation of other areas of the brain too. For example if the stimulation is on the motor areas, you experience a kind of dancing or rhythmic writhing movements of your limbs (called Jacksonian march in med lingo). If this happens around areas of sensations, you might experience peculiar (familiar or unfamiliar) tastes or smell or very often hear voices. Remember that Temporal lobes hold the areas of Speech, hearing, word comprehension and eloquence. When these conditions are worsened by other conditions like Schizophrenia or Paranoia, you start feeling as if someone is guiding or commanding you.

Now, what’s so much about epilepsy?

For decades, neuroscientists have noted striking correlations between Spiritual (“self-realisation”) feelings and Epileptic fits. The seat of emotions in the brain is a small structure called Amygdala, a bunch of neurons cuddled up into the size of a small goose berry . It’s deeply seated in the temporal lobes on either side. The Amygdala, along with other related connections like Hippocampus, mammillae and hypothalamus, together forms the Limbic System ; also called Papez-Limbus Circuit (in memory of the great anatomist James Papez who discovered this structures in his attempt to track the pathway of infection of Rabies virus in humans). 


The limbic system gets its input signals from all sensory systems. After processing these signals, the Limbic system decides the appropriate emotional response to the experience. This outward expression is guided tightly by Hypothalamus, through the release of chemical signals called hormones. You thus decide to cry/shout at/ flee from/weep/moan or feel ecstatic as is the response from brain. 


As I said earlier, you can have epileptic activity in any region of your brain. And the most striking response of people with such a misfiring in the Limbic System is “….a feeling of divine presence..”. They suddenly start to see profound cosmic significance in even trivial objects or experiences. They very often say that they “…suddenly received answers to all of their life’s queries…!” All these responses have been documented through simulation studies using electromagnetic signal stimulation of specific brain areas in labs. These kind of people who have auto-stimulation of Limbic system are also eloquent about their trivial personal experiences. They keep elaborate diary notes of day to day experiences, keep preaching about being “selected by god to reveal the truth” and quite often claim to hear “angels” speak..!!

Curious enough, even Atheists do seem to have such visions! All these “visions” and “oneness – with – the – cosmos” kind of feelings are modified based on the patient’s or subject’s convictions. A “UFOlogist” might see himself shaking hands with E.T! An Atheist on the other hand might re-experience a long cherished moments in life. He may also experience a kind of inexplicable pleasantness or relaxation.

Some near-death experiences have been evoked experimentally in people, at the Laurentian University by Michael Persinger and at the Centre for Brain at University of California by VS Ramachandran. The lack of oxygen in these areas of the brain during near death situations triggers epileptic firings in Limbic System, which in turn result a flurry of the so called “visions of the nether world”.

And so..?

What is the Evolutionary significance of this kind of neural responses.? Why have we evolved such a mechanism?

Think again… trace our steps back…We said at the outset, that such activities are very often found in or around the areas of Speech, hearing, word comprehension and eloquence. A person who is naturally prone to such “tickling” of the emotion-centers of the brain, is a natural born leader. He keeps thinking that he is “the chosen one” and keeps preaching ideas that later add up to social rituals and finally culminate in a belief-sect or a religion. The history of religions stands testimony to this.
And what about the common man? He is endowed with a limbic system that makes him inclined to believe/experience spirituality and the so called “oneness with the divine”. As age progresses, the conglomeration of these “experiences” during his life time makes him more religious. This mechanism has great socio biological significance as it is a “selfish” mechanism that improves the bondage within a particular clan /religious sect / family. Nature in short favors this trait genetically, because it makes a person loyal to his community. And a loyal member always ensures better survival and protection of that community’s genome.

Celebrations, festivals and religious “get togethers” always have a spiritual flavor because of this reason. They are evolutionary mechanisms aimed at bringing together, people sharing same ideology.

A terrorist dying in the name of jihad or a Swayam Sevak fanatic bringing down a mosque in the name of “patriotism” might all be exaggerated evolutionary expressions of this loyalty to ones own group…!


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