Relationship between Brain Structure and Intelligence: A Gray and White Matter Analysis

Abstract

Brain development is not uniform in all individuals, as it presents differences influenced by the predominant type of intelligence in each person. Among these, logical-mathematical intelligence plays a fundamental role, as it favors the development of other forms of intelligence. From a psychological perspective, two types of intelligence are distinguished that, together, make up the g factor proposed by Spearman: crystallized intelligence and fluid intelligence. The former is linked to knowledge accumulated over time and with experience, demonstrating a strong association with verbal processing. Fluid intelligence, for its part, is oriented toward flexible reasoning and the resolution of novel situations. Genetic bases of intelligence. The genetic influence on the development of intelligence is considerable. It has been identified that a significant number of genes related to specific functions also intervene in essential neurological processes, such as synaptic plasticity, cellular interaction, and energy metabolism. These functions are especially linked to the activity of neurons located in the cerebral cortex and midbrain. Recent research suggests a possible correlation between human intellectual performance, expressed in intelligence quotient (IQ), and certain characteristics of pyramidal cells, such as the size of their dendrites and the speed with which they conduct action potentials.