Cortical dynamics of spatial and non-spatial auditory selective attention

Abstract

Auditory selective attention suppresses processing of task-irrelevant stimuli, and it is crucial for effective communication in social settings. Previous studies showed that space- and pitch-based auditory attention engages different neural networks. However, the cortical dynamics underlying spatial and non-spatial auditory attention are unclear. Since accumulating evidence suggests that selective suppression is related to alpha band oscillation (8–14 Hz), we examine the spatial and non-spatial attentional modulation of alpha oscillation power as well as event-related potential (ERP) and behavioral performance. Using Electroencephalography (EEG) in humans, we compare behavior and physiological measures during focused attention (where listeners maintain focus on one “target” stream) and broad attention (where listeners are prepared to switch attention to a “super-target” stream which may or may not appear after the “target” stream) in spatial and non-spatial settings. We find that spatial attention shows overall stronger alpha power and different distribution in the central-parietal cortex. We also find that the monitoring cost of broad attention is higher in spatial attention, which is supported by a stronger ERP modulation. Our findings help elucidate the cortical dynamics involved in spatial and non-spatial auditory attention.