Abstract
Spatial orienting is typically understood as being driven either by external events (reflexive attention) or by the current goals of an individual (voluntary attention). Functional neuroimaging studies indicate that the two modes of orienting are controlled by two interdependent networks, (i) the ventrolateral frontoparietal network, that is involved in processing of unexpected target events, and (ii) the dorsolateral frontoparietal network that is responsible for maintenance of task goals and coordination of the two networks. In the last 10 years, numerous studies have reported that spatial attention is obligatorily shifted in the direction of perceived eye gaze direction. While the behavioral profile of this social orienting effect is consistent with reflexive orienting, the neural networks that control it remain poorly understood. Here we examined the temporal sequence of brain activity associated with shifts of social attention elicited by eye direction using electroencephalography and Multiple Source Beamformer (MSBF) analyses. MSBF analyzes changes in EEG oscillatory activity in a specific frequency band and depicts the neural generators of the spectral density in 3D space. Participants were presented with spatially uninformative central eye direction cues and were asked to detect an onset of a peripheral target while their EEG was recorded from 64 channels. Replicating previous reports, behavioral data revealed that participants were faster to detect targets appearing at gazed-at relative to not gazed-at locations. Cue-related MSBF analyses focused on the theta band (4–8Hz), which is thought to be a carrier frequency for attentional control operations. This analysis revealed increased spectral density in the theta band during the post-cue interval in regions of the ventrolateral frontoparietal network, including the temporalparietal junction, middle frontal gyrus, and ventrolateral frontal cortex. These results suggest that, in addition to processing of unexpected events, ventrolateral attentional control network may play a significant role in directing social attention.