Neurofunctional Differences Between the Processing of Short and Long Auditory Time Intervals

Abstract

Abstract Previous psychophysical studies have suggested that time intervals above and below 1.2 second are processed differently in the human brain. However, the neural underpinnings of this dissociation are still unclear. In the present study, we investigate whether distinct or common brain networks and dynamics support the passive perception of short (below 1.2s) and long (above 1.2s) empty time intervals. Twenty participants underwent an EEG recording during an auditory oddball paradigm with .8- and 1.6-s standard time intervals and deviants. We computed the auditory event-related potentials for each condition at the sensor and source levels. Then we performed cluster-based permutation statistics around N1 and P2 time periods, testing deviants against standards. At the sensor level, fronto-central components were elicited by deviance detection during N1 for long intervals, and during P2 for short intervals. Source reconstructions revealed that for short intervals, deviance detection was associated with activity in the left auditory cortex, bilateral supplementary motor areas and bilateral cingulate cortices. For long intervals, deviance detection was associated with activity in the left inferior parietal sulcus (IPS), bilateral cingulate cortices, and the right motor cortex. These results suggest that distinct brain dynamics and networks support the perception of short and long time intervals. Main Text