The Brain Networks Basis for Deductive and Inductive Reasoning: A Functional Magnetic Resonance Imaging Study

Frontoparietal (FPN) and cingulo-opercular network (CON) control cognitive functions needed in deductive and inductive reasoning via different functional frameworks. The FPN is a fast intuitive system while the CON is slow and analytical. The default-interventionist model presents a serial view of the interaction between intuitive and analytic cognitive systems. This study aims to examine the activity pattern of the FPN and CON from the perspective of the default-interventionist model via reasoning.

We employed functional magnetic resonance imaging (fMRI) to investigate cingulo-opercular and frontoparietal network activities in 24 healthy university students during Raven and Wason reasoning tasks. Due to the different operation times of the CON and FPN, the reaction time was assessed as a behavioral factor.

During Raven's advanced progressive matrices (RAPM) test, both the CON and FPN were activated. Also, with the increase in the difficulty level of the Raven test, a linear increase in response time was observed. In contrast, during the Wason's selection task (WST) test, only the activity of FPN was observed.

The results of the study support the hypothesis that the default-interventionist model of dual-process theory provides an accurate explanation of the cognitive mechanisms involved in reasoning. Thus, the response method (intuitive/analytical) determines which cognitive skills and brain regions are involved in responding.

The cingulo-opercular and fronto-parietal networks (FPNs) control cognitive functions and processes.The frontoparietal network is a fast intuitive system that utilizes short-time attention which is compatible with type 1 processing. In contrast, the cingulo-opercular network (CON) is an analytical time-consuming system that utilizes attention and working memory for a longer time, compatible with type 2 processing.The default-interventionist model of a dual-process theory states that our behaviors are controlled by type 1 processing unless we are confronted with novel and complex problems in which we have no prior experiences.

The present study examined the activity of two task-based brain networks through performing diffrent type of reasoning tasks. Fronto-parietal and Cingulo-opercular are the two task-based brain networks that are responsible for cognitive control. These two brain networks direct the way to use cognitive skills and executive functions which are necessary to perform cognitive tasks especially higher-order ones as reasoning tasks. Since the two types of inductive and deductive reasoning tasks requier two different bottom-up and top-down cognitive control respectively, different cognitive skills would be needed which affect the activity of fronto-parietal and cingulo-opercular brain networks. Our results showed that through inductive reasoning task which examined by RAVEN, both of the fronto-parietal and cingulo-opercular brain networks were activated but deductive reasoning task which examined by Wason Selection Card test, just the fronto-parietal brain network was activated. It seems that in the case of deductive reasoninf task, there is a higher probability of errors which lead to giving less correct responses. Based on our results, subjects paid not enough attention to details, so had failure to update informations that leaded to responding with errors. Inactivity of cingulo-opercular network through dedeuctive reasoning task clearly showed that the bottom-up cognitive control did not happen successfully. As a result of that, information processing did not proceed properly.