Gavin studies categorization and the perceived similarity of sounds and objects. Mostly, similarity and categories depend on comparisons of features like color, shape, tone, or density. Occasionally, recent experiences, goals, familiarity, mood, and other contexts also influence decisions. Gavin uses computer neural models to simulate how these factors may influence categories and similarity in the brain. This research can potentially be applied to medical and satellite imaging, x-ray screening, voice recognition, and other fields.