Cognition & Neuroscience

Cognition & Neuroscience

The purpose of the present essay is to briefly describe some of the fundamental concepts discussed in neuroscience and cognition. The human brain contains four lobes (frontal, parietal, temporal and occipital). On the one hand, the frontal lobe represents the seat of executive function. Executive function is defined as planning, decision-making, organizing, impulse inhibition and other personality traits. The frontal lobe’s neural connections mature up through adolescence, which is why teenagers may seem impulsive.

Conversely, executive dysfunction are deficits in this area. Executive dysfunction is diagnosed by the WCST (Wisconsin Card Sorting Test) and relates to perseverative errors (perseveration is not to be confused with perseverance, the further carrying a negative connotation and the latter a positive one). In the test, perseverative errors lead subjects with executive dysfunction to persist in the chosen card sorting criterion, despite the administrator’s repeated clues to alter card sorting criteria.

Further, frontal lobe damage, as shown by lesion studies, results in executive dysfunction. One of the most famous cases in the executive dysfunction literature is the tragedy of Phineas Gage, a rail-road worker who got injured by a metal rod going through his skull during a horrible explosion accident. He survived, but underwent dramatic personality changes due to extensive frontal lobe damage.

Cognition. Photo by Elena

Alternatively, another very famous case in psychological research is that of patient H.M. (mistakenly interpreted as the ‘Hippocampus Man’). Patient’s H.M.’s story shed light on the dissociation between implicit and explicit types of memory. Memories can further be episodic and semantic, as well short term (such as working memory, which can hold up to 7 to 10 items at a time), and long term. Also, memories transfer from short term to long term memory storage through a process known as consolidation, during which they are malleable (McGill University).

Eyewitness testimony is likewise malleable through suggestion. For instance, in one study subjects reported cars going at different speeds after watching the same video, depending on which words the examiners used. Along these lines, the hyppocampus is the strcutre most closely linked with memory, while the amygdala plays a role in the formation of emotional memories. In relation to the hypppocampus, a study of taxicab drivers in London, UK, showed that they had larger hyppocampi than general controls. However, science remains unclear on the causality of such a correlation.

On the other hand, cognition is mainly associated with the parietal lobe and grey matter. However, myelin (the fatty substance covering axons) speeds up transmission, and thus communication, between neurons. Moreover, cognitive psychologists refer to several types of intelligences, namely spatial, verbal, kinaesthetic, interpersonal (social), intrapersonal (insight), mathematical, physical and musical. IQ or intelligence quotient were initially developed by Alfred Binet as school placement tests. The most widely used IQ tests today remain the Wechsler scales (Wechsler Intelligence Scale for Children – WISC and Wechsler Adult Intelligence Scale – WAIS). Mensa is an international association with people with much higher than average IQ scores. In contrast, mental retardation refers to IQ scores below 70 points. IQ variation in the general population follows a normal distribution or the bell curve, with most of the population clustering between 85 and 115 points.

IQ tends to remain stable throughout an individual’s lifespan, although tests may be inaccurate for different reasons, including but not limited to, repeated administration and experience, native vs. second language wording of questions, cultural biases and so on. As a general rule, such quantitative instruments test spatial, mathematical and verbal ability. Further, the left hemisphere is most closely associated with verbal and mathematical skills, while artistic ability is concentrated in the right hemisphere. The corpus callosum, is the central commissure facilitating communication between the two hemispheres, as evidenced by lesion studies treating epilepsy.

Conversely, another measure of ability and intelligence refers to EQ or emotional quotient. Nonetheless, numbers and scores may not necessarily be good and accurate predictors of later success in life, but studies do vary on the subject. Interestingly, the ability to delay gratification (by distracting oneself from coveted stimuli, for instance) appears a better predictor of educational/academic and occupational/vocational success. Thus, the purpose of the present essay was to outline the basic concepts in cognition and neuroscience, especially as they relate to psychology.