From Sensory Processing to Conscious Perception

Perception is more than meet’s the eye; how we see the world is critically shaped by top-down factors, specifically attention (what is relevant) and as a growing body of work indicates, by expectations about what the world probably looks like (what is likely). In my talk, I will discuss how attention and expectation may affect sensory processing in the brain and thereby perception – drawing from empirical data in human subjects using behavioral methods, (intracranial) EEG, and neuroimaging. These data reveal a role for not only cortical, but also subcortical (i.e., striatal), regions in determining our perception of the external world. Collectively, they underscore the importance of studying the separate effects of attention and expectation on sensory processing in the brain. They also indicate a more critical role for basal-ganglia dependent gating mechanisms in perception than has long been assumed.