Direct Structural Connection between Auditory-temporal and Visual-occipital motion selective regions

Gurtubay Antolin, Ane [UCL] Battal, Ceren [UCL] Maffei, Chiara [Harvard Medical School] Rezk, Mohamed [UCL] Mattioni, Stefania [UCL] Jovicich, Jorge [University of Trento] Collignon, Olivier [UCL] et al.[show all]

crucial perceptual skill for optimal interaction with a multisensory environment. In primates, including humans, the middle-temporal region (hereafter, hMT+/V5) specializes in processing visual motion signals, while the Planum Temporale (hereafter, PT) specializes for auditory motion processing. It has been hypothesized that these regions can communicate directly to achieve fast and optimal multisensory integration of motion signals. However, the existence of direct anatomical connections between these regions remains unexplored. We therefore evaluated the presence of anatomical connections between the hMT+/V5 and the planum temporale (PT). Each participant was first involved in an auditory and visual motion localizer in order to define PT and hMT+/V5 functionally. Then, using diffusion imaging data, we reconstructed white matter tracts between these individually and functionally defined motion selective regions. Probabilistic tractography was conducted between each pair of regions (PT to hMT+/V5 and reversely) and a connection was considered as reliable at the individual level when it had a minimum of 10 streamlines. Our preliminary results show reliable connections between hMT+/V5 and PT, suggesting the existence of this direct pathway between these visual and auditory selective regions.