The overall goal of this study is to provide a better understanding of the organization of human cortical systems involved in the perception of sound location, movement, and the layout of auditory space. To achieve this goal, functional magnetic resonance imaging (fMRI) will be used to differentiate, map and functionally characterize human brain regions involved in auditory spatial perception and attention. Emphasis will be placed on (1) first mapping several well-established subdivisions of the cortex that are related to hearing and/or spatial processing. These functional landmarks will then be used to (2) assist in identifying and mapping cortical pathways specialized for analyzing the spatial attributes of sound and/or controlling attention directed to stimuli in auditory space. Finally, (3) we will use recent advances in 3D sound production in conjuction with high resolution fMRI to identify cortical maps of auditory space. Subjects will perform auditory or audio-visual behavioral tasks while functional images are acquired with a 1.5T G.E. Signa clinical scanner and a 3.0T Bruker scanner (which will allow for higher resolution imaging), using echo-planar or clustered-acquisition pulse sequences for T2 weighted functional images. The fMRI experiments are designed to allow high fidelity sound to be delivered during silent periods of the scanning process, thereby minimizing or eliminating interference associated with scanner noise. Together, the experiments in this project seek to identify cortical systems responsible for perception of the spatial attributes of sound. The experiments will provide detailed maps of corresponding functional specialization in temporal and parietal cortex and will extend our understanding of auditory function in humans. In addition to its relevance for understanding the neural basis of auditory space perception, the results of this study may also be of significant use in understanding and diagnosing deficits in auditory space perception associated with brain damage.