Age Dynamics of intelligence in Adolescence and Early Adulthood

Abstract

Our study aimed to analyse age-specific IQ changes in adolescence and early adulthood and to identify structural changes in intelligence at three stages of IQ of development - 14, 15 and 19-20 years. To estimate age-specific intelligence dynamics WISC, WIAS, SPM, EFT and academic achievement were used. It was shown that stabilization of intelligence as an integrated system is not simultaneous, but it begins at the stage of growth of intelligence through sequential stabilization of its partial functions. It was found age specific features of intelligence development: 1) a significant integration of verbal intelligence functions occurs from 14 to 15 years, which remains unchanged from 15 to 19-20 years; 2) against the background of stabilization of verbal functions from 15 to 19-20 years, the degree of cross-functional interactions considerably increases. The unity of verbal and nonverbal mechanisms of analytical-synthetical activity is formed. The findings revealed that the formation of intelligence structures determining the productivity of intellectual activity derives from chaos to order, from forms of relative globality and undifferentiatedness toward new forms of ever-increasing differentiation and hierarchical integration.