Tactile and visual motion direction processing in hMT+/V5.

The human motion complex hMT+/V5 is activated not only by visual motion, but also by tactile and auditory motion. Whilst direction-selectivity has been found within this complex for visual and auditory stimuli, it is unknown whether hMT+/V5 also contains direction-specific information from the tactile modality. In the current study, we sought to investigate whether hMT+/V5 contains direction-specific information about visual/tactile moving stimuli. Leftward and rightward moving stimuli were presented in the visual and tactile modalities in an event-related fMRI design. Using region-of-interest-based multivariate pattern analysis we could decode the two motion directions for both tactile and visual stimuli in hMT+/V5. The activity patterns of the two modalities differed significantly, indicating that motion direction information from different modalities may be carried by distinct sets of neuronal populations. Our findings show that hMT+/V5 contains specific information about the direction of a moving stimulus in both the tactile and visual modalities, supporting the theory of hMT+/V5 being a multimodal motion area.