The Perception and Evaluation of Visual Beauty
Neuroscience and Neurobiology
What are the perceptual and cognitive processes that underlie our experiences of beauty? In this dissertation, I describe a series of experiments where we used functional magnetic resonance imaging (fMRI) and behavioral methods to explore the mechanisms of perception, reward representation, and decision-making during evaluations of face and place beauty. In our first study, we used fMRI to ask whether evaluative signals in frontal cortex contain category-specific information or whether these signals are encoded as a "common currency" across reward types. By comparing neural activity correlated with subjective ratings of face and place beauty, we showed overlapping activity in dorsal ventromedial prefrontal cortex (vmPFC), consistence with the common currency hypothesis. At the same time, our results revealed category-specific patterns of activity in ventral vmPFC and in lateral orbitofrontal cortex (latOFC), suggesting at least a partial distinction in the frontal networks recruited during the processing of different types of rewards. In a follow-up study, we used fMRI to further examine face-responsive "patches" of activity in latOFC by measuring response in these patches while subjects evaluated but did explicitly rate face beauty. Our results demonstrated a similar pattern of response to that observed during explicit ratings, suggesting that reward-related activity in this region is not dependent on a decision-making task. Lastly, in a series of behavioral studies, we developed a novel experimental design to measure the influence of recent trial history on current judgments of face attractiveness. We found that attractiveness judgments are simultaneously contrasted away from the attractiveness of the previous face but assimilated towards the previous numerical rating given. Our results also suggested that these influences are not specific to attractiveness judgments but may be linked to more general properties of perception and decision-making. Collectively, this work furthers our understanding of the neural mechanisms underlying evaluations of face and place beauty, and illuminates some of the specific contextual influences on these evaluations.