Abstract
It is well established that faces induce both faster orienting responses and more involuntary saccades than other stimuli. Here we used functional magnetic resonance imaging (fMRI) to investigate the interaction between eye-movements programming and the privileged processing of social stimuli at the neural level. We asked 17 healthy adults (7 females) to look towards (pro-saccades) or away (antisaccades) visual stimuli. They performed the task while either faces or cars stimuli appeared to the left or right of the center of the screen. FMRI time-series were acquired using a 3-T fMRI scanner. We processed and analyzed the data using both the general linear model and multi-voxel pattern approaches. We focused on regions of interest belonging to the extended face- perception and to the oculomotor-control brain networks. We also selected brain areas not directly involved in eye-movement control but frequently activated to a greater extent for anti- compared to pro-saccades (Jamadar et al., 2013). Both methods revealed the expected activation pattern when comparing anti- and pro-saccades, including, bilaterally, the frontal and supplementary eye-fields (FEFs and SEF), the superior parietal cortex, the precuneus, the insula and the anterior cingulate cortex. Likewise, faces induced greater activation than cars in expected brain regions including the fusiform and occipital face areas and the amygdala. We observed a significant interaction between task and stimulus class only in a region within the left insula, which showed large difference between anti- and pro-saccades for faces but not for cars. These results provide no evidence of different recruitment of the oculomotor network as a function of the social nature of the stimuli. Instead they suggest that the insula, a region known to be involved in emotion processing and cognitive control, might be a substrate of higher conflict processing linked to performing an anti-saccade away from a face.
Meeting abstract presented at VSS 2016