A cortical visual processing pathway that runs caudal to rostral from the occipital lobes in the primary visual cortex to dorsal temporal cortex and parietal lobes, and processes information relative to recognizing the spatial locations of whole objects as well as serving to visually guide on-line actions related to objects that are made in the ‘here and now’ (e.g., reaching). It has been portrayed as providing automatic, unconscious ‘vision for action’. Together with the superior colic’s and pulvinar, it is one of two main functional pathways of the primate primary visual cortex, the other being the ventral stream that is assumed to be phylogenetically older. The dorsal stream begins with purely visual functions in the occipital lobe before gradually transferring to spatial awareness at its termination in the parietal lobe. The latter, or more specifically the posterior parietal cortex, is deemed to be essential for the perception and interpretation of spatial relationships, but also for learning tasks involving coordination of movements in space. If the latter involves the coordination of eye movements during reading, then this may account for why some dyslexics perform poorly on tests requiring dorsal stream functions. There is also a suggestion that the development of the dorsal stream, unlike the ventral stream, is adversely affected by deafness. Sometimes referred to as the parietal pathway or the spatial vision pathway, the dorsal stream was first defined and described by Leslie G. Ungerleider and Mortimer Mishkin in 1982. Together with the ventral stream, it forms part of the influential two-visual systems hypothesis
See Cortical lobes, Cerebral cortex (functions), Common coding, Dorsal, Dyslexia, Entorhinal cortex, Inferior parietal lobe (IPL), Occipital cortex (or lobe), Parietal cortex, Primary visual cortex (V1), Pulvinar, Rostral, Superior colliculus, Two visual systems hypothesis, Ventral visual pathway (or stream)