Visually guided locomotion: Behavior, chemical inactivation, and electrophysiology

As a human or cat walks across cluttered terrain, they rely on vision to avoid stepping on objects. We used behavioral methods, chemical inactivation, and electrophysiology to investigate the visual processing underlying visually guided walking in cats. Our work can be summarized into five projects which asked: (1) What region of the visual field do cats use to plan their steps in a cluttered environment? (2) Is step planning done consciously or is it pre-attentive? (3) What pathways in the brain underlie this behavior? (4) How do neurons in one region of the motion-sensitive pathway of the brain respond during visually guided walking? (5) How do neurons in this area respond during other visually guided behaviors? Novel electrophysiological methods were developed to record from single neurons in awake, unrestrained cats during vigorous behavior. We present novel findings on visual processing during walking. We also present single unit recording data from area LS of the cortex during unrestrained behavior. Our data suggest that area LS plays a large role in the analysis of moving objects. We discuss these findings within the context of visually guided locomotion and hunting behavior.