The representation of bodies in high level visual, prefrontal and inferior parietal cortex varies with explicit vs. implicit expression perception

Abstract

Recent studies provide an increasingly understanding of how visual objects categories like faces or bodies are represented in the brain but also raised the question whether a category based or more network inspired models are more powerful. Two important and so far sidestepped issues in this debate concern, first, how major category attributes like the emotional expression directly influence category representation and second, whether category and attribute representation are sensitive to task demands. This study investigated the impact of a crucial category attribute like emotional expression on category activity and whether this varies with the participants task. Using (fMRI) we measured BOLD responses while participants viewed whole body expressions and performed either an explicit (emotion) or an implicit (shape) recognition task. Our results based on multivariate methods show that the type of task is the strongest determinant of brain activity and can be decoded in EBA, VLPFC and IPL. Brain activity was higher for the explicit task condition in VLPFC and was not emotion specific. This pattern suggests that during explicit recognition of the body expression, body category representation may be strengthened, and emotion and action related activity suppressed. Taken together these results stress the importance of the task and of the role of category attributes for understanding the functional organization of high level visual cortex.