Human brain areas involved in the analysis of auditory movement

This work tests the hypothesis that a network of areas involving bilateral premotor cortex and right parietal cortex subserves the analysis of sound m ovement. The components of this network have been examined at the level of individual subjects in a study where 720 fMRI scans were acquired per subje ct. Additionally, the effect of movement direction was investigated by vary ing this property systematically. Linear sound ramps that are perceived as movement toward one side of the head or the other were used in an experimen t in which the principal contrast was between movement, and a stationary co ntrol stimulus made up of identical component interaural phase and amplitud e cues. In a group analysis, the network of bifrontal and right parietal ar eas suggested by previous work was confirmed. The frontal activation includ ed both dorsal premotor activity in the region of the frontal eye fields an d discrete ventral premotor activation in an area corresponding to primate areas for multimodal spatial analysis and motor planning. The right parieta l activation included both superior and inferior parietal cortex. Analysis of the individual data showed a similar pattern of activation in each subje ct, with the greatest variability within the right parietal area. The patte rn of activation did not vary when the direction of movement was varied, su ggesting that both directions of movement are represented in the network we have demonstrated. Hum. Brain Mapping 9:72-80, 2000. (C) 2000 Wiley-Liss, Inc.