Chang, E. 1 , Lin, C. 2 , Huang, H. 1, 2 , Huang, T. 2 , Tzeng, O. J. 3 & Hung, D. 1
1 Institute of Cognitive Neuroscience. National Central University. Jhongli, Taiwan
2 Brain Research Center. National Chiao-Tung University. Hsinchu, Taiwan
3 Academia Sinica. Taipei, Taiwan
This functional magnetic resonance imaging (fMRI) study examined the acute effect of social-evaluative stress on task switching. Participants performed a switching task under both stressful (negative feedback about performance) and control (no feedback) conditions. Behavioral results indicated a trend of shorter RTs and smaller local switching effect in the stressful than in the control condition. Voxelwise GLM analysis of BOLD signals revealed that while stress modulated activations for global switching effect in visual regions (right middle occipital gyrus and cuneus), it had a wider spread influence on activations for local switching effect across anterior (bilateral putamen; right caudate and medial frontal gyrus) and posterior areas (right middle occipital gyrus, precuneus and cuneus, lingual gyrus ). Interestingly, in the local-effect related region-of-interests (ROIs), activations for single task blocks were smaller in the stressful than in the control condition, whereas activations for repeated trials in the mixed task blocks showed the opposite pattern. On the other hand, in the global-effect related ROIs, activations for switched trials remained constant regardless of stress, while those for repeated trials were larger in the stressful condition. To conclude, task switching requires executive processes that are differentially prone to the influence of social evaluative stress.