Relationship between Intelligence and Executive Functions in Preschoolers

Abstract

The paper raises the problem of the relationship between executive functions and intelligence in preschool period of the development. Based on the discussion about the components of executive functions proposed by different authors, two components (inhibitory control and working memory) were selected for analysis. Raven Coloured Progressive Matrices were chosen for the assessment of the intelligence. We chose this method due to the fact that there are a lot of preschoolers who have speech problems that prevent an adequate assessment of verbal intelligence. The go/go and go/no-go paradigms to evaluate inhibitory control (Vergunov & Nikolaeva, 2009) and a test aimed at evaluating working memory (Razumnikova & Savinykh, 2016) were used. The specificity of the test aimed at the level of inhibitory control assessment was a fractal structure of the sensory flow. Both go/go and go/no-go series included two identical parts, but children did not know about this. Some children, however, showed better results in the second part of the series rather than the first one. This could indicate that children intuitively discovered the structure of the sensory flow and learned to respond more effectively. In go/go series, children were asked to respond to each presented stimulus (circles of different colours). In the go/no-go series, they were forbidden to respond to a target stimulus (red circles). Calculating the mistakes (reactions to the red circles), we could assess the inhibitory control level. To assess a working memory, the subjects were offered three series including the same set of visual stimuli, and the order of the stimuli was changed in each series. The number of recalling stimuli in each series and interference inhibition resulting from the presentation of the same set of stimuli were calculated. The study involved 90 preschoolers (average age 6.5±0.4 years) of normative development, parents of all children signed informed consents, and all children were told about the goals of the study. It was shown that nonverbal intelligence has no correlation with any parameters of the inhibitory control or parameters of working memory in preschool age. Immaturity of the prefrontal cortex at this age was suggested to be the main reason for the lack of such a link. The low levels of both inhibitory control and interference inhibition could not provide a high level of correlation with intelligence. It was proved that nonverbal intelligence is associated with greater performance in the second part of the go/go series. This suggests that the higher the child's intelligence is, the better they are able to navigate the sensory flow.