16. Ulusal Sinirbilim Kongresi, İstanbul, Türkiye, 20 - 23 Mayıs 2020, cilt.12, sa.1, ss.69
Objective: It is limbic structures that step in fast and bias decisions under uncertainty rather than high cortical structures that are responsible for evaluating the choices rationally. It is aimed to test the idea above by modifying the IGT to affect limbic structures.
Methods: Thirty-two right handed and healthy medical faculty students, of which %62.5 (n=20) was male, participated into the study. Two groups were created and their members were equalized in their mean age, gender and class distribution. In cued group there were negative emotion inflicting animal pictures on cards A and B and positive ones on cards C and D. Neutral group saw neutral pictures. After structural imaging they played modified IGT during fMRI. Preprocessed data was investigated for activation and connectivity patterns.
Results: The groups were equal in their alexithymia, state anxiety, decision-making styles, impulsivity, and reward/punishment sensitivity scores. Cued group preferred advantageous cards more often than neutral one. Within groups there were so many clusters that decrease their activation. Only one cluster increased activity towards the end of the task in neutral group. In cued group one cluster (all left, sup., inf., mid. and med. frontal cortex, dor. ACC and partially ven. ACC, SMA, pre and paracentral gyri) decreased its activity in comparison to neutral group. It was determined that this region increased its connectivity towards the end of the task in two clusters: ant. ACC right para-cingulate gyrus., right sup. motor cortex; precuneus cortex and post. cingulate. Posterior DMN, left fronto-parietal network, language network and cerebellar network increased their activation towards the end of the game in neutral group.
Conclusion: As indicated in somatic marker hypothesis, the participants benefited from emotional cues. Although they were not told about the function of the pictures, cues seem helped limbic system to improve the performance.