PSYC 311 Lecture Notes - Lecture 15: Inferior Temporal Gyrus, Posterior Parietal Cortex, Two-Streams Hypothesis

• School: McGill University
• Department: Psychology
• Course: PSYC 311
• Professor: Michalakis Petrides

Document Summary

Object vision and spatial vision: two cortical pathways. The striate cortex is the source of 2 multisynaptic corticocortical pathways: the ventral stream (interconnecting striate, prestriate, and inferior temporal areas) and the dorsal stream (interconnecting striate, prestriate, and inferior parietal areas). The ventral stream allows for the visual identification of objects (object vision), whereas the dorsal stream allows for the visual location of objects (spatial vision). This facilitates the cognitive association of visual objects with other events such as emotions or motor acts. The dorsal stream is an occipitoparietal projection system that follows the course of the superior longitudinal fasciculus. This stream interconnects the striate, prestriate, and inferior parietal areas and is critical for the visual location (visuospatial analysis) of objects. The dorsal stream subsequently links to dorsal limbic and dorsal frontal cortical structures. This enables the construction of spatial maps, as well as the visual guidance of motor acts that were initially triggered by activity in the ventral pathway.