Different neural network for exogenous temporal expectations under sub-second and supra-second in fMRI

Timing is required for both estimating the duration of a presently unfolding event, and forecasting when a future event will occur. When participants used a dynamic visual spatio-temporal trajectory stimulus to predict the final position, exogenous temporal expectations are engaged. However, it is still not clear whether different neural networks are used to measure sub-second and supra-second temporal durations. Here, we used fMRI to find out the differences between brain activity which measure 600ms and 1800ms in an exogenous temporal expectation task. We observe bilateral anterior cingulate cortex (ACC) show significantly activated during sub-second, bilateral MT+ [suggested to contain both middle temporal (MT) and medial superior temporal (MST)], right superior parietal lobule (SPL), and left inferior parietal cortex (IPC) are more active in the 1800ms condition. Overall, this research shows that maybe different components are used for sub-second and supra-second in exogenous temporal expectation.