Abstract
Visual processing of scenes provides important cues for affective perception. While many previous studies investigated affective perception of facial expressions, the neural basis of affective visual processing for scenes remains largely unknown. By using fMRI, we measured brain activation when participants were shown gray-scale scene pictures with a wide range of contents and of various levels of rated fearfulness. In each scan run, 30 images with 5 levels of rated fearfulness were shown in a random sequence to participants for 2s each and followed by a 12s fixation period. Participants were asked to do a 2AFC task judging whether the image presented was fearful or not. Each participant went through 9 of such scan runs. In addition, regions of interest (ROI) in temporal and occipital lobes were functionally localized with separate scan runs by contrasting brain activation corresponding to an independent set of fearful images versus scrambled images. Our results suggest that brain activity in ROIs of the fusiform gyrus and lateral occipital cortex (LOC) closely correlated with the level of fearfulness of the scenes. By contrast, other visual areas in the occipital lobe were found to be insensitive to the varying degrees of fearfulness in our stimuli, suggesting that our results in the fusiform and LOC were unlikely caused by general arousal of attention status. Brain activity in other ROIs is analyzed for comparisons. Moreover, multivariate pattern analysis is performed to further evaluate the functional role of these ROIs. Our results provide brain imaging evidence for the neural basis of affective visual processing for fearful scenes.
Meeting abstract presented at VSS 2012