Across the back of the brain is an area of the cerebrum—the occipital lobe—that is dedicated to processing visual information into meaningful chunks of perceptional material. The region is divided into a number of subregions, known as the primary visual cortex, the ventral stream, and the dorsal stream. The primary visual cortex processes low-level descriptions of orientation, spatial frequency and colour properties, whereas the ventral stream, sometimes called the “what” pathway, provides important information for the identification of stimuli, and the dorsal stream, sometimes called the “where” or “how” pathway, helps guide movement in response to outside stimuli.

Image showing dorsal stream (green) and ventral stream (purple) in the human brain visual system. (https://commons.wikimedia.org/wiki/File:Ventral-dorsal_streams.svg)