Dissociation and convergence of the dorsal and ventral visual streams in the human prefrontal cortex.

Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Athinoula A. Martinos Center for Biomedical Imaging, Charlestown, MA 02129, USA
NeuroImage (Impact Factor: 6.36). 10/2012; 65. DOI: 10.1016/j.neuroimage.2012.10.002
Source: PubMed


Visual information is largely processed through two pathways in the primate brain: an object pathway from the primary visual cortex to the temporal cortex (ventral stream) and a spatial pathway to the parietal cortex (dorsal stream). Whether and to what extent dissociation exists in the human prefrontal cortex (PFC) has long been debated. We examined anatomical connections from functionally defined areas in the temporal and parietal cortices to the PFC, using noninvasive functional and diffusion-weighted magnetic resonance imaging. The right inferior frontal gyrus (IFG) received converging input from both streams, while the right superior frontal gyrus received input only from the dorsal stream. Interstream functional connectivity to the IFG was dynamically recruited only when both object and spatial information were processed. These results suggest that the human PFC receives dissociated and converging visual pathways, and that the right IFG region serves as an integrator of the two types of information.

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    • "Of interest, the functions of the dorsal and ventral visual region may not be independent of each other. The right ventral region and the dorsal region have been found to be structurally or functionally connected to each other and to converge in the prefrontal cortex in a study of the neural mechanism for face recognition (e.g., Takahashi et al., 2013). When reading, the left ventral visual region, such as the left occipitotemporal cortex (OTC; McCandliss et al., 2003; Shaywitz and Shaywitz, 2005; Richlan et al., 2009; for reviews), has been consistently found to engage in word processing. "
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