丁鼐（Ph.D，New York University）
时间： 2014-08-29 14:00 - 16:00
地点： 哲学楼103
Natural sensory stimuli, e.g. speech, music, and visual scenes, often come in sequences. Perception of sensory sequences critically relies on the neural representation of temporal order. I argue that the perceived temporal structure is represented by the temporal sequencing of cortical activity, and test the hypothesis using the example of speech perception. Using magnetoencephalography (MEG), we demonstrate that as the listeners integrate smaller speech units into larger linguistic structures (e.g., words into phrases and sentences), distinct time scales emerge in cortical activity, mapping hierarchically embedded linguistic structures into temporally coupled cortical dynamics. Furthermore, in complex listening environments, cortical activity is selectively synchronized to the temporal structure of speech and largely invariant to the listening background, which provides a plausible mechanism to direct attention to sensory events in time. Taken together, these results strongly suggest that the sequencing of cortical activity mediates the structural parsing and attentional selection of sensory sequences.2014-08-29
2014-08-29