Current studies in the Cognitive Neuroscience Section focus on planning, thinking, and reasoning; memory and amnesia; visual attention, spatial perception, and object recognition; and emotion-social cognition. Both single-case and group design studies are used. Normal controls, inpatients, and out-patients with central nervous system impairment are recruited for studies. Planning, thinking and reasoning are studied in experiments focusing on schema development, generation of cognitive plans, analogical thinking, script event generation and verification, number processing and calculation, knowledge representation, and divided resources Memory and amnesia are studied in experiments focusing on implicit and explicit encoding and retrieval, priming, autobiographic recall, discourse processing, naming and word retrieval, and categorization tasks. Visual attention, spatial perception, and object recognition are studied in experiments focusing on spatial frequency, contrast sensitivity, object knowledge and feature verification, visual- spatial localization, spatial, selective, and sustained attention, and local-global properties of stimuli. Emotion and social cognition are studied in conjunction with cognitive experiments examining attention and memory, rule retrieval, and inhibition. The development of theoretically valid and testable models of cognitive processing is a primary aim of the Section. We study patients with focal and degenerative lesions in order to topographically map components of cognitive processing to brain regions and systems. Pharmacologic challenge and infusion studies are done to evaluate the dissociability of hypothesized components of cognitive processing. Transcranial magnetic stimulation, functional magnetic resonance imaging, positron emission tomography, and event- related brain potentials are all employed to examine the topographic location and computational properties of cognitive components.