Primary Sensory Areas

Synonyms

Auditory cortex; Somatosensory cortex; Visual cortex

Definition

Areas of the cerebral cortex that receive the first signals from sensory receptors are called primary sensory areas. These areas are separate for each sensory modality, but the major primary sensory regions are those for vision, hearing, and sensation.

Vision: Primary visual cortex lies in the lingual gyrus of the occipital lobe on both sides of the calcarine sulcus. Histologically termed Brodmann’s area 17, primary visual cortex is organized topographically, such that each part of the cortex represents a specific part of one’s visual field.

Hearing: Primary auditory cortex lies along the upper bank of the temporal lobe in the transverse temporal gyri, also termed Heschl’s gyrus. Histologically, the neurons comprising primary auditory cortex (A1) are labeled Brodmann’s areas 41 and 42. Auditory information from both ears is processed in both the right and left hemispheres, and the organization is tonotopic:...