Poster E33, Monday, March 26, 2:30-4:30 pm, Exhibit Hall C
Effective connectivity in the cognitive control network
Fan Zhang1,2, Sunao Iwaki2,1; 1University of Tsukuba, 2National Institute of Advanced Industrial Science and Technology
Inhibitory control plays the extremely important function in people’s daily life. From the research on lesion and imaging studies, the pre-supplementary (pre-SMA)/supplementary motor area(SMA), inferior frontal gyrus(IFG) and basal ganglia (BG) are responsible for the rapid inhibition and switching between multiple options in motor reaction. These regions compose the cognitive control network for actions. However, two important questions remain to be addressed. First, it is not clear the roles of these regions in the cognitive control for inhibition. Secondly, the interactions between regions during the inhibition are still in the debate. We use stop-signal paradigm and functional magnetic resonance imaging (fMRI) to analyze the whole-brain contrasts, and use Bayesian Model Selection to compare the dynamical causal models (12 models) that represent the effective connectivity between IFG, SMA, Subthalamic nucleus (STN), Putamen,Thalamus and Primary Motor Cortex (M1) in cognitive control network. The results from whole brain contrasts and dynamic causal model with Bayesian model selection show that: IFG modulates the connection from SMA to STN. Both IFG and SMA are recruited to detect the important cues, and SMA acts as the key role in the suppression of unwanted motor response via hyperdirect pathway. Furthermore, we find the activation of Putamen, however, Bayesian parameter between Putamen and other regions are zeros, which means the 'stop' behavior is the result of race between hyper-direct pathway and direct pathway.
Topic Area: EXECUTIVE PROCESSES: Monitoring & inhibitory control