Intelligence: What is it and are the IQ tests correct?!


According to Oxford dictionary, “intelligence” means “The ability to acquire and apply knowledge and skills.” Webster dictionary defines “intelligence” as “the ability to learn or understand things or to deal with new or difficult situations.” Webster has another definition for “intelligence” that is related to CIA and other governmental spy agencies as “Secret information that a government collects about an enemy or possible enemy; also : a government organization that collects such information.” The medical dictionary online has this definition for intelligence: “The ability to learn and to deal with new situations and to deal effectively with tasks involving abstractions.” Wikipedia has a broader definition: “Intelligence has been defined in many different ways including one’s capacity for logic, understanding, self-awareness, learning, emotional knowledge, memory, planning, creativity, adaptive behavior, problem solving and self-control. It can be more generally described as the ability to perceive information, and retain it as knowledge to be applied towards adaptive behaviors within an environment or context.”

Intelligence has been defined in many forms, e.g., logic, abstract thought, comprehension, self-awareness, learning, emotional, retaining, planning, invention, creation, problem solving, etc. An editorial statement by fifty-two researchers defines the intelligence as “A very general mental capability that, among other things, involves the ability to reason, plan, solve problems, think abstractly, comprehend complex ideas, learn quickly and learn from experience. It is not merely book learning, a narrow academic skill, or test-taking smarts. Rather, it reflects a broader and deeper capability for comprehending our surroundings—”catching on,” “making sense” of things, or “figuring out” what to do.” (1)

Generally speaking of intelligence, comes of mind IQ or Intelligence Quotient that is measured by different tests including Stanford-Binet, Raven’s progressive matrices, the most currently used Wechsler intelligence scales for children and adults, the Kaufman assessment battery for children, etc. Some tests consist of a single type of task; others rely on a broad collection of tasks with different contents (visual-spatial, verbal, numerical) and asking for different cognitive processes (e.g., reasoning, memory, rapid decisions, visual comparisons, spatial imagery, reading, and retrieval of general knowledge). The psychologist Charles Spearman early in the 20th century carried out the first formal factor analysis of correlations between various test tasks. He found a trend for all such tests to correlate positively with each other, and named it g for “general intelligence factor”. He interpreted it as the core of human intelligence that, to a larger or smaller degree, influences success in all cognitive tasks and thereby creates the positive manifold. This interpretation of g as a common cause of test performance is still dominant in psychometrics. (2)

From Alertness to Attention to Intelligence:

For someones intelligence to kick in or to be tested, the person first needs to be awake and alert, to pay attention and stay focused. Attention that is the gate to the brain for its higher functions of cognition, executive functions and intelligence, has poorly been studied and addressed in the neurocognitive and intelligence studies, so the IQ tests suffer from such deficiency and come short of precise measurement of intelligence! I have discussed in detail elsewhere (3-4) on the subject of ADHD (Attention Deficit Hyperactivity Disorder) that such shortcoming has led many and on top, the experts in the field to presume wrongly that ADHD is associated with low intelligence and learning disabilities. In fact I have shown with scientific evidence, borrowed from cognitive neuroscience studies that ADHD is associated with high intelligence. (4) These shortcomings and misunderstandings are rooted in the lack of knowledge or realization of different types of attention, as the gate to the higher functions of the brain, including intelligence. ADHD and IQ studies are relying on sustained attention that is only one type and in fact archaic type of attention. Lets see what are the other types of attention and why the others are wrong!

 Attention and its different types:

Attention is the cognitive process of concentrating on one aspect of the environment while ignoring other things. (5) Within cognitive science, attention has been divided into following:

1.Sustained attention (vigilance): The ability to maintain a consistent behavioral response during continuous and repetitive activity.

2.Selective attention: The ability to maintain a behavioral or cognitive set in the face of distracting or competing stimuli. Therefore it incorporates the notion of “freedom from distractibility.”

3.Alternating attention: The ability of mental flexibility that allows individuals to shift their focus of attention and move between tasks that having different cognitive requirements.

4.Divided attention: This is the highest level of attention and it refers to the ability to respond simultaneously to multiple tasks or multiple task demands. (5-10)

Sustained Attention:

ADHD studies, labeling this condition as “attention deficit” and linking it wrongly to low intelligence and learning disabilities are only based on “sustained attention” that is only one type of attention, repetitive, stationary and not dynamic. Sustained attention, is the ability to stay focused in long-term, even on boring tasks such as classroom settings, without the power or choice of selection, that usually the physically and mentally hyperactive subjects of ADHD are not good at. In fact human imaging studies have demonstrated that activation of frontal and parietal cortical areas, mostly in the right hemisphere, are associated with sustained attention performance. This is interesting as majority of human’s higher cognitive function and intelligence are the functions of the left than the right hemisphere. (7)

Selective Attention:

In selective attention, the subject has the capability of filtering out non-interested subjects and selectively zoom the attention like a camera lens on the interested tasks. Neuroimaging and electrical recording results have indicated that selective attention amplifies neural activity in pre-striate areas in suppression of multiple stimuli to focus or zoom on the interested stimulus. The competition among multiple stimuli to distract the attention is both bottom-up or sensory-cortical and top-bottom or cortical-sensory, so the brain in selective attention does a lot of neural work to stay focused. (8-10) Subjects with selective attention, may not pay attention to the surroundings and anything else and may not even respond when they are addressed.

 Alternating (Shifting) Attention:

In alternating or shifting attention, the subject has the cognitive flexibility or the ability to change or shift attention between subjects. Dopamine activity has been associated with cognitive flexibility and alternating or shifting attention, and several frontal, pre-frontal, parietal and striatum of the brain are contributing in this type of attention. (11) Both selective and alternating/switching attentions require intelligence and are developmental and fundamental to almost all cognitive tasks. In other words, brains with more capacity of selective and alternating/switching attentions are advanced. At the same time, the processes underlying these two aspects of attention may overlap and connect in important ways, leading to related developmental trends.” (12)

Divided Attention:

Divided attention, the most advanced and developed type of attention, is the task of actively paying attention to more than one task at a time, which has becoming more and more necessary in every day of modern digital and fast paced life. How well people divide their attention has to do with that person’s intelligence. According to researchers, more intelligent people can timeshare between more than one task and effectively perform more tasks at the same time. (13) Positron emission tomography (PET) has identified more than one area of the brain or neural systems visually involved in selective and divided attention. But outside the visual system, selective and divided attention activate non-overlapping sets of brain regions. (14) While all types of attention are related to intelligence, more and more in our era, divided and flexibility in attention (alternating/shifting) are required and considered pre-requisites for high and dynamic intelligence. (15-6)

Bottom-up vs. Top-down attentional processing:

In addition to the different types of attention, described above, the source of stimulus or task targeting the brain or our attention, are either “bottom-up” or “stimulus-driven”, or “exogenous attention” is driven by the properties of the objects and target our senses, such as motion or a sudden loud noise or the feeling of the chair seated on, that attract our attention in a pre-conscious, or non-volitional way. The sensory areas of the brain such as parietal and temporal cortices, as well as the brainstem are involved in this attentional process. In contrast, the other attentional process, the “top-down” one, also known as goal-driven, endogenous or executive attention is under the volitional control of the person. It is mediated primarily by the frontal cortex and basal ganglia, and is important in the executive functions, working memory, conflict resolution and inhibition. (17-9)

 Neuroanatomical Correlates of Intelligence:

While it was once thought that basically the grey matter of the brain is responsible for the higher cognitive functions including intelligence, later studies have confirmed that the white matter of the brain, is as important. White matter of the brain that is mostly made of glial cells, and once thought its function is solely gluing the neurons of different areas of the brain together (so the name of “glia” means glue), acts basically as the highways of the brain, without it there will be no efficient and sufficient communication and function in the brain. Also intelligent individuals use their neurons more efficiently through more efficient of glucose consumption of the neurons and better synaptic connections between neurons, and more and better white matter myelination to enhance more efficient neural transmission. (20)

The evolution of the humans brain from the apes, has not been only in the increase in the size of the brain, but convolution or folding of the brain surface, as the head could not get bigger than what we have. Therefore over the course of evolution, the cerebral cortex has grown considerably in surface area, which seems to be not only the result of a larger brain but, perhaps more importantly, of an increased folding of the brain’s surface. It has been suggested that the high degree of cortical gyrification in humans may be a morphological substrate that supports some of our species’ most distinctive cognitive abilities. Consequently, individual intelligence within the human species might be modulated by the degree of cortical convolution. Also the volume of the corpus callosum or sub-regions have been found to be important in several studies, for more efficient inter-hemispheric information transfer. (20)

Intelligence and information processing in the brain is not limited to the frontal and pre-frontal lobes, but temporal, parietal, occipital lobes, hippocampus, and the cerebellum. Ludres et al. (21-22) have shown that intelligence scores are positively associated with the degree of folding in the temporo-occipital lobe, particularly in the outermost section of the posterior cingulate gyrus (retrosplenial areas), and also posterior callosal thickness as an efficient inter-hemispheric information transfer. Subcategorizing intelligence to different components of skills, talents or task performance, would involve different specific neuroanatomical regions, (e.g., verbal task demands the left inferior prefrontal and posterior temporal lobe; visuo-spatial demands the parietal lobe; information encoding and retrieval, the hippocampus; and executive functions including problem solving, planning, reasoning, etc., the frontal cortices). (23)

 Another anatomical correlate of intelligence is the degree of the brain development, neuronal and glial and synaptic pruning. From early on in life, brain itself like a gardener, prunes and removes the un-needed neurons and glia cells, through “programmed cell death” or “apoptosis”. The last stage of anatomical development of the brain is synaptic pruning that continues up until mid 20’s so to make the garden of the brain more adaptive and functional. This synaptic reorganization is dependent upon the individual’s age, gender, and environmental stimulation along with many other variables. Therefore high intelligence is associated with better overall brain cells and synaptic pruning, having more efficient neuronal, glial cells and synapses. (24-25) So while the brain cortical thickness (only 1.5-4.5 mm thick) in early life is negatively, later on in adult life it is positively correlated with intelligence. (26) Therefore the cortical thickness is more closely related to intellectual abilities than the volume of gray or white matters of the brain. (27) But this correlation is not that simple as the cerebral cortex consists of layers of cells organized into columns that vary in depth, depending on the number and thickness of layers, the types of neurons and glial cells, their size and density. These underlying cytoarchitectural characteristics defining cortical thickness vary within different cortical regions of the brain that are in charge of different skills, talents and types of intelligence. (28-30)

Neurochemical Correlates of Intelligence:

Previc in 1999 (31) proposed a general theory attributing the origins of human intelligence to an expansion of dopaminergic systems in human cognition. Dopamine is postulated to be the key neurotransmitter regulating six predominantly left-hemispheric cognitive skills critical to human language and thought: planning, working memory, cognitive flexibility, abstract reasoning, temporal analysis & sequencing, and generativity. Previc contended that a dopaminergic expansion has advanced humans’ evolution from apes, increasing cortical dopamine levels by augmenting tyrosine and its conversion to dopamine in the central nervous system, increasing the brain size, and the cortical convolution.

The COMT (catechol-O-methyltransferase) enzyme metabolizing dopamine has a polymorphism with two alleles of Methionine (Met) and Valine (Val). The Val allele is an evolutionarily recent G (guanine) to A (adenine) missense mutation resulting in a substitution of methionine (Met) for valine (Val) in the COMT enzyme. (32) In the human brain, Met/Met homozygotes having about 40% less COMT activity than Val/Val homozygotes that has 60% in the prefrontal cortex. In other words, the Met/Met homozygotes brain use less, while Val/Val homozygotes use more dopamine for higher cognitive and intelligent functions. Therefore intelligent people have more val/val homozygotes gene, while most people carry on Val/Met heterozygotes with an intermediate or average level of intelligence. (33-34)

 Functional brain imaging studies, for the most part have suggested that the same brain regions that are engaged by working memory tasks, in particular its reliance on selective attention e.g., prefrontal cortex (PFC), are also recruited during performance on intelligence tests. (35-36) It has also been shown there is a relationship between general intelligence and dopamine signaling in the prefrontal cortex, specifically an up-regulation in three dopamine-related genes (Darpp-32, Rgs9, and Drd1a). (37)

These genes seem to interact to enhance synaptic plasticity and the efficacy of dopamine receptor (D1) to improve learning and intelligence, and dampens the downstream effects of D2 activation that inhibits such higher cognitive functions. (38-39) Hereby via this genetic and neurochemical mechanism, dopamine signaling efficacy in the prefrontal cortex acts to enhance learning and general intelligence, by increasing the activity of dopaminergic midbrain neurons and the dopamine levels in the prefrontal cortex increase. (1238-9) It has also been shown the connectivity between the striatum and the prefrontal cortex is enhanced for the better performance on both working memory tasks and general intelligence batteries. (40-41)

 Interestingly the fMRI (Functional Magnetic Resonance Imaging) studies have demonstrated that activity levels in the PFC and the basal ganglia are increased prior to filtering of irrelevant information in selective attention tasks (42) PFC neurons persistently fire through dopamine excitation during a working memory task to stabilize persistent activity and protect it from interference. Through this mechanism, the PFC maintains attention towards goal relevant information and to ignore salient distracters. Therefore there is a significant and proximal relationship between working memory capacity/selective attention and general learning abilities. (43-44)

Independent of the above mentioned three dopamine-related genes (Darpp-32, Rgs9, and Drd1a), only one other gene, Nudt6 (also known as basic fibroblast growth factor; bFGF), expressed by astrocytes (or glia cells in the brain white matter) acts as a potent trophic factor to promote the survival of prefrontal cortical neurons to enhance learning and intelligence. (45)

 The IQ tests: Are they measuring the true intelligence?

As humans, we have been always after easy tests and quick solutions! But as discussed earlier, in the case of “intelligence” and in general any sophisticated function of the brain as such, there is no accurate test or easy solution. As we will see in the following, no IQ tests could measure truly the multifaceted humans’ brain functions and in this case, our intelligence. As we will read most IQ tests (that all could not be analyzed here) are designed and relying on our cognitive function, reasoning and somewhat logic, but they ignore all the talents and skills that a human could have out of the higher cognitive realm. How even Einstein’s intelligence, that is in the sphere of logic, reasoning and higher cognitive function could be measured by the current IQ tests?! How Beethoven’s intelligence, which is out of logic and reasoning context, but emotional, invention and musical talent could be measured?! On this token, how an actor, artist, or athlete’s intelligence or talent could be measured by IQ tests?! Is there any measuring scale for “invention”, “creation”, “innovation”, different types of “problem solving”, “critical thinking”, “proposal thinking”, or even as simple as “common sense” in the current IQ tests?!(46-47) Lets see:

The current popular IQ tests: Stanford-Binet and Wechsler’s

For the sake of space and time, here I will focus on the two common IQ tests of Stanford-Binet and Wechsler’s. The current Stanford-Binet IQ test or scale that is in its 5th edition, is an update of the original IQ test of Binet-Simon scale that was created by the French psychologist, Alfred Binet and his student Theodore Simon in 1905. The test was originally designed to detect children with significantly below-average intelligence and mental retardation. Failing to find a single identifier of intelligence, Binet and Simon instead compared children in each category by age, so the test merely was a comparison between the subject and the average normal children. In 1916, the American psychologist, Lewis Terman at Stanford University, released a revised version of Binet-Simon scale as the “Stanford–Binet IQ test”. This new version that is currently in popular use, attempts to identify not only children with learning disabilities and below average intelligence, but also to measure the above average levels of intelligence. The original test in the 1905 form included, measurement of tactile and visual perceptions, recognition of food, execution of simple commands and imitation of simple gestures, verbal knowledge and naming of objects and pictures, immediate comparison of lines of unequal lengths and weights, repetition of figures, verbal definition of known objects, repetition of sentences, comparison of known objects from memory, memory recall of pictures, drawing a design from memory, immediate repetition of figures, resemblances of objects, weights to be placed in order, exercise upon rhymes, verbal gaps to be filled, synthesis of words in sentence, reply to abstract questions, reversal of the hands of a clock, paper cutting, and definitions of abstract terms. (48)

The current Stanford–Binet IQ test, now in its fifth edition, released in 2003, measures five weighted factors and consists of both verbal and nonverbal subtests. The five factors being tested are knowledge, quantitative reasoning, visual-spatial processing, working memory and fluid reasoning. The knowledge subset is on vocabulary, procedural knowledge and recognizing picture absurdities. The quantitative reasoning set of the test covers non-verbal and verbal reasoning. The visual-spatial processing subset measures the recognition of form board and form patterns, position and direction. The working memory part of the test measures delayed response, block span and memory for sentences. The quantitative reasoning set of the test covers early reasoning, recognizing verbal absurdities, analogies and object series matrices. (49)

 The Wechsler Adult Intelligence Scale (WAIS) and The Wechsler Intelligence Scale for children (WISC) are founded by David Wechsler ‘s in 1955 as a better measurement of intelligence than Binet-Simon’s or Stanford-Binet’s based on his definition of intelligence as “… the global capacity of a person to act purposefully, to think rationally, and to deal effectively with his environment.” He believed that intelligence was made up of specific elements that could be isolated, defined, and subsequently measured. He also wanted to incorporate non-intellective factors as variables contributing to the overall score of intelligence, such as lack of confidence, fear of failure, attitudes, etc. The test or the full scale IQ (FSIQ) is divided into verbal IQ (VIQ) and performance IQ (PIQ). The verbal IQ measures verbal communication and working memory, through vocabulary, recognition of similarities, general information, comprehension, arithmetic, digit span, and letter-number sequencing. The performance IQ measures perceptual organization and processing speed through picture completion, block design and matrix reasoning, digit symbol coding and symbol search. (50)

 As discussed and predicted, the current IQ tests and scales measure general information and knowledge and general cognitive and logical or reasoning abilities that are basically based on “sustained attention” at the cost of ignoring other types of attentions. Selective, alternating or switching, and divided attentions, that elsewhere I have coined them as “Dynamic attentions” (3-4) could not be measured by the current IQ tests. That is why subjects with ADHD of hyperactive/impulsive subtypes who possess such dynamic attentions, while struggle with sustained attention, may score low on the current IQ scales. The present IQ tests also fail to measure many other skills and talents, as discussed above, such as artistic and athletic ones as they are solely based on the cognitive/memory, logical & reasoning, information and knowledge, which are mostly functions of frontal, specially pre-frontal lobes of the brain, and no where else.

So it seems to be time first to understand then change the definition of intelligence, so to design the new IQ tests and scales. Intelligence is not simply “The ability to acquire and apply knowledge and skills.” as Oxford dictionary defines it, nor as Webster dictionary defines “the ability to learn or understand things or to deal with new or difficult situations.” Intelligence is not either according to the medical dictionary online, “The ability to learn and to deal with new situations and to deal effectively with tasks involving abstractions.”, nor even fits the broader definition of Wikipedia as “capacity for logic, understanding, self-awareness, learning, emotional knowledge, memory, planning, creativity, adaptive behavior, problem solving and self-control.” Most of these old-fashioned definitions are foremost in the realm of learning or understanding, and dealing or coping with difficult or new situations, which is basically problem solving or adaptive behavior. Other than Wikipedia’s broad definition, the others do not cover “logical capacity”, “planning”, or “creativity”. But Wikipedia’s definition that has probably borrowed from many places, is too broad and thin and includes “self-awareness, emotional knowledge, and self-control” that are not much related to the subject of intelligence.

Many subjects with high intelligence and dynamic attentions, as we see in the case of ADHD, do not seem to have much of self-awareness and self-control, but are impulsive and behaviorally disinhibitedoreover other than creativity as a major component of intelligence that should encompass innovation and invention, there is no room for different skills and talents, “critical thinking”, “common sense”, and any type of the dynamic attentions. We all know that some people genetically are better in certain skills and talents and are fast learners in certain areas, while others could not be easily taught those skills. Discussing about skills, in different disciplines require so many natural or genetic talents, for example in music, perfect ears or hearing, appreciation of harmony and dynamic, etc., and in the sports, the coordination and balance of different body parts and senses, that translate in the topographic of the brain, to the perfect association and communication between different correspondent areas, such as different motoric cortex, with different sensory cortex, related subcortical areas and all in a perfect concert with the higher cortical parts of different frontal and pre-frontal and striatal areas of the brain. For example the simple “eye-hand” or “eye-foot” coordination covers a broad and overlapped areas of the brain as discussed earlier, and these skills in some are innate and natural, though with practice could improve. Another example is “aiming” that some people are almost born with it, while others with many years of practice could not reach their levels. The same is other aptitudes of rhyming and lyrical writing, painting, etc., that the list in so many skills and talents are beyond this paper.

Before reaching the conclusion of this article, I would like to discuss briefly about “emotional intelligence” and “artificial intelligence” to clarify some confusions and controversies.

Emotional Intelligence:

Emotional intelligence (EI) term first appeared in a 1964 paper by Michael Beldoch, and it gained popularity in the 1995 book by that title, written by Daniel Goleman, despite controversy and criticism within the scientific community. (51-52)EI has been defined as the capacity of individuals to recognize their own, and other people’s emotions, to discriminate between different feelings and label them appropriately, and to use emotional information to guide thinking and behavior. Over time, the term that is more popular and used in psychology and sociology than medicine and psychiatry, has been also used as a personality trait, linking it leadership performance. Some researchers have argued against such effect of EI on performance that is more related to personality traits. and general intelligence. Therefore emotional intelligence has not been accepted yet by most scientists to be different than general intelligence or personality traits, and studies on the subjects by proponents have been criticized for poor research methodology that has exaggerated the significance of EI. (53-54)

 Artificial Intelligence:

Artificial intelligence (AI) is a new form of intelligence, made by humans with computers to simulate own intelligence and in some aspects beyond and faster. Although the AI could like any computer acts and responds and solve some mathematical problems faster, it is still limited by the operating mechanism of a computer. Since any computer’s language or means of operation, is based on a hierarchical response or reaction of 0 or 1, “yes” or “no”, there is no flexibility, rational, emotional, creative, unpredictability, and else of the human’s brain and intelligence. This is despite the strenuous efforts of artificial intelligence science to copy the human’s intelligence by getting help not just from mathematics, but , psychology, linguistics, philosophy, and neuroscience. In fact artificial intelligence is a good example that human’s intelligence is not only in the realm of learning, memory, acquiring knowledge and even mathematical logic, but far beyond to other mental capabilities, skills and talents with flexibility that could not be mimicked by machines.  


For conclusion, lets discuss two great historical figures who could easily and popularly be associated with high intelligence with no controversy. These two legends are one from antiquity, “Socrates” and one from the modern time, “Albert Einstein”, both in different forms unusual, not ordinary and not matching any of the definitions of “intelligence” as briefed in this article and could perhaps fail in the current available IQ tests.


 Socrates (469-399 BC), an enigmatic figure with his “Socratic questioning” method has been so influential on the western philosophy for thousands of years after him that the foundation of pedagogy (educational methods) and epistemology (studies the nature of knowledge, the rationality of belief, and justification) all have been indebted to him. The method and concept of dialectics that was popularized in the west by Hegel, and later on influenced many principal branches of western philosophy of Marx, Nietzche, existentialism and even psychology, psychoanalysis, cognitive therapy and DBT (Dialectical Behavior Therapy), are all owed to this icon. Socrates who worked as a stonemason, did not even record his own thoughts and methods, but his works have been recorded through his great philosopher students, Plato and Xenophon and the plays of Aristophanes, all his contemporaries. This ordinary man by his work, but a legend by his thoughts, had been unconventional so at the end was executed by the Roman authorities, for poisoning their youngsters’ minds! His trial in some detail written by Plato is a classic work and includes some of Socrates wisdom that to this day is still with us, long after the fall of Roman empire. (55-59)


Albert Einstein(1879-1955) that by many equals the definition of high intelligence and smartness, clashed with authorities and resented the conventional school’s regimen and teaching method in his hometown, Ulm in Germany and moved to Switzerland. He later wrote that the spirit of learning and creative thought was lost in strict “rote learning” that is based on memorizing and not critical questioning and learning. This symbol of intelligence, failed his first exam at the Swiss Federal Polytechnic in Zürich, in the general part, though obtained exceptional grades in physics and mathematics. Later on he was graduated from a four-year mathematics and physics program at the Zürich Polytechnic, but it took him two frustrating years to find a teaching position, that upon failure, he settled with a job in the patent office with the help of his father. It was in this office that he as an evaluator of applications, learned about different proposal and theories and later on, he came up with break through theories that made the foundation of modern physics. Of Einstein’s great achievements as many know, are the general theory of relativity, one of the two foundations of modern physics alongside quantum mechanics, the world’s most famous equation of E = mc2, discovery of the law of the photoelectric effect, a pivotal step in the evolution of quantum theory, and the foundation of the philosophy of science. (60-61)

With the above two exemplary models of high intelligence and with what have been presented in this brief article, we learn that “intelligence” as it has been conventionally defined and measured by the current IQ tests, is not only about “learning” and “memory” or other component of “cognition”, even “executive function”! Perhaps to correct the traditions perspective of “intelligence”, we could re-define it as “creativity” and “problem solving”. But this new definition, while better than the archaic ones, is still in the domain of “thoughts” and “logic”, or “mathematics” and “physics” or “science” in general, and anatomically in the domain of frontal and prefrontal lobes.

But what about the other forms of intelligence, skills and talents. How we could fit genius in arts, music and sports among other subjects, within the subject of “intelligence”? Perhaps the best comprehensive definition of “intelligence” to cover all domains, would be “giftedness” that lay people have been using it for ages. This definition of “giftedness” while covers and includes almost all forms of intelligence, talents and skills, it is not a general term, but very specific. One cannot be gifted in many subjects, but in majority of cases in one or perhaps a few at the most. This will correspond better with the anatomical mapping of intelligence, skills or talents, as each part of the brain is specialized in certain specific function or task. Many of these giftedness, seem to be “innate”, and genetic, though epigenetic and environment of learning and practice will perfect them, while it would be hard to reach a level of giftedness without the innate ingredient and only by learning.

 The current IQ tests at the best differentiate between normal average, above and below in the matter of learning and higher cognitive functions, and are useful for diagnosis of learning disability and neuro-developmental delay disorders, but obviously cannot identify high intelligence and giftedness. Even on the subject of cognitive assessment, since majority of these tests are based on “sustained attention”, they easily miss on the “dynamic attentions” that are more by-products of the most recent aspects of the brain evolution. As we move up on the ladder of our evolution, basically because of our brains, the new “dynamic attentions” of selective, switching and divided attentions with their capacity of “multi-tasking” and “fast-paced” tasks performance will be able to survive the law of the fittest!

Dr.Mostafa Showraki, MD, FRCPC                                                                  Lecturer, School of Medicine, University of Toronto,Author: “ADHD:Revisited” Book/ “”/””         


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