His research focuses on sensorimotor processes that are used to acquire and produce learned behaviors. Vicario's laboratory utilizes behavioral, physiological, and anatomical techniques to study important aspects of the vocal communication system in developing and adult songbirds, including the acquisition and patterning of learned vocalizations, auditory discrimination and auditory memories for species-typical vocal sounds, and how auditory information relevant to vocal learning reaches defined vocal motor regions in the forebrain.