Neurocognitive mechanisms of interindividual differences in cognitive abilities

• Applicant: Professorin Dr. Anna-Lena Schubert
• Subject Area: General, Cognitive and Mathematical Psychology
• Term: since 2021
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 492991901

Individual differences in the speed of information-processing contribute substantially to individual differences in intelligence. Results from studies using mathematical models of decision making and chronometric analyses of the event-related potential suggest that more intelligent individuals show a specific advantage in the speed of stimulus-analysis and stimulus-evaluation processes. However, it is not yet clear how this speed advantage contributes to overall cognitive performance. Based on the integration of previous findings from the fields of intelligence research, cognitive psychology, and cognitive neuroscience, a neurocognitive process model is proposed that assumes that more intelligent individuals benefit from a greater white-matter tract integrity of frontoparietal networks, which in turn contributes to higher functional connectivity within and between neural networks underlying working memory and cognitive control processes. It is assumed that measures of neural processing speed reflect a greater efficiency of these neural networks and that individuals benefit from a more efficient transfer of information between memory systems and higher cognitive control. The model proposes that this benefit in working memory processes facilitates solving intelligence test items that require the simultaneous representation of several pieces of information and sub-hypotheses. It therefore suggests that the effect of structural connectivity on intelligence test performance is fully mediated by working memory processes and their neural correlates. The proposed neurocognitive process model will be tested using structural equation models that assess the constructs in the proposed process cascade (structural connectivity, functional connectivity, processing speed, working memory capacity, intelligence) with at least three indicators each and that systematically test cross-sectional relations between the constructs in a sample of 200 young adults with heterogeneous educational backgrounds. The project allows for the integration of different data sources that are highly relevant to the current theoretical discussion in intelligence research in a unique way. Moreover, by combining differential and experimental approaches, the project overcomes the separation of the two disciplines criticized by Cronbach (1957).

• DFG Programme: Research Grants