2011 April ; 12(4): 217–230 | Dwight J. Kravitz, Kadharbatcha S. Saleem, Chris I. Baker, and Mortimer Mishkin
The paper proposes a new neural framework for visuospatial processing, redefining the dorsal stream as a multifaceted system rather than a single-purpose pathway. The dorsal stream, originally characterized as mediating spatial perception ('Where'), is now understood to support both conscious and non-conscious visuospatial functions. The authors identify three distinct pathways emerging from the dorsal stream: a parieto-prefrontal pathway, a parieto-premotor pathway, and a parieto-medial temporal pathway. These pathways support spatial working memory, visually guided action, and navigation, respectively. The parieto-medial temporal pathway, which is the focus of this paper, involves projections to the medial temporal lobe through the posterior cingulate and retrosplenial cortices. The authors review anatomical and functional evidence to support their framework, highlighting the complex interplay between these pathways and their contributions to visuospatial processing. They conclude that the dorsal stream is a widespread visuospatial processing system that integrates information from multiple cortical areas, contributing to both spatial perception and non-conscious spatial processing.The paper proposes a new neural framework for visuospatial processing, redefining the dorsal stream as a multifaceted system rather than a single-purpose pathway. The dorsal stream, originally characterized as mediating spatial perception ('Where'), is now understood to support both conscious and non-conscious visuospatial functions. The authors identify three distinct pathways emerging from the dorsal stream: a parieto-prefrontal pathway, a parieto-premotor pathway, and a parieto-medial temporal pathway. These pathways support spatial working memory, visually guided action, and navigation, respectively. The parieto-medial temporal pathway, which is the focus of this paper, involves projections to the medial temporal lobe through the posterior cingulate and retrosplenial cortices. The authors review anatomical and functional evidence to support their framework, highlighting the complex interplay between these pathways and their contributions to visuospatial processing. They conclude that the dorsal stream is a widespread visuospatial processing system that integrates information from multiple cortical areas, contributing to both spatial perception and non-conscious spatial processing.