Discusses techniques for studying large-scale brain activity, insights from computational modeling, and cognitive processes that could lead to a better understanding of cognition. Describes interactions between psychology and physiology in perception, structural levels of organization in the nervous system, techniques and research strategies. (RT)

Explains the hierarchic structure of the mammalian visual system. Proposes a model in which feedback pathways serve to modify sensory stimuli in ways that enhance and complete sensory input patterns. Investigates the functioning of the system through computer simulations. (ML)