In recent clinical studies, the planum temporale has been implicated in a number of disorders ranging from autism to schizophrenia. This brain region appears to be involved in several critical functions from language processing to integration of auditory, visual, and motor functions. In spite of its central role in sensory/cognitive functions, very little is known about how this brain area is organized. This study seeks to fill this gap through a series of functional magnetic resonance imaging (fMRI) studies that investigate the activation patterns for speech perception, the functional basis for sensory-motor activation, the neural networks that support the interaction of spatial hearing and speech processing, and the relation between spatial-speech integration and visual-speech integration. A more thorough understanding of the functional organization of this region may lead to more effective treatment strategies for cognitive dysfunctions.