Abstract
For years, the amygdala has been implicated as a brain structure dedicated to rapidly processing emotionally salient stimuli in the environment. Recently, it has been proposed that the amygdala has a more general role in orienting attention to socially salient stimuli. For instance, Adolphs et al. (Nature, 2005) found that SM, a patient with rare bilateral lesions of the amygdala, was unable to recognize fearful facial expressions because she failed to fixate the eyes of the faces. The eyes are particularly informative social stimuli, and therefore may be ones that the amygdala is particularly biased to detect. The present study examined whether this same patient (SM) fails to fixate the eyes of people when they are presented within complex social scenes. We also investigated the role of context in which the scene occurs on SM's pattern of fixations. We presented a variety of real world social scenes (Birmingham, Bischof & Kingstone, Visual Cognition, 2008) under three task conditions: one asking viewers to report where people in the scene were directing their attention, a second asking viewers to describe the scene, and a third asking viewers to describe what kind of room the scene was taking place in. Across all three conditions, SM looked less often at the eyes relative to control participants. Comparing the different tasks, we found that both SM and controls looked more often at the eyes when asked to report on the social attention in the scene. These results suggest that amygdala damage may lead to a specific reduction of exploration of other people's eyes, but that task instructions can modulate this bias to some extent. The findings extend our prior work with isolated faces and corroborate the view that the amygdala helps orient attention to certain socially salient stimuli, notably and perhaps specifically, the eyes.
This research was funded in part by grants from NIMH and the Simons Foundation.