Poster C6, Sunday, March 25, 1:00-3:00 pm, Exhibit Hall C
Neural mechanisms of reflexive social attention: a combined eye-tracking and fMRI study
Lara Rösler1, Matthias Gamer1; 1Julius Maximilians University of Würzburg, Würzburg, Germany
When being presented with pictures of naturalistic scenes, humans rapidly allocate attention to social features (i.e. human heads or bodies) within these scenes. Various eye-tracking studies have confirmed that this social attention takes place reflexively and independently from the physical saliency of competing image areas. What remains unknown, however, is which neural mechanisms facilitate this rapid allocation of social attention. A viable candidate region is the amygdala which might modulate local activity in early visual cortex and thereby facilitate saccade preparation or execution towards social features. In the current study, we presented naturalistic scenes with social features in one quadrant of the visual field for 200 ms to 37 participants while simultaneously recording eye movements and brain activity using functional magnetic resonance imaging. On the behavioral level, participants made significantly more saccades towards social cues than a distribution of saccades at chance level would imply. Activity changes in early visual cortex reflected the localization of social features in the visual field and were modulated by the occurrence of saccades. However, on the level of univariate analyses, amygdala activity did not differ between trials with saccades towards social features as compared to trials in which saccades were executed towards non-social image regions. It seems possible that localization of social features in the visual field or the elicitation of saccades are rather represented in multivariate patterns of amygdala activity. Collectively, our findings support the notion of a reflexive component of social attention that is reflected in early visual cortex activity.
Topic Area: ATTENTION: Other