What is Primary Somatosensory Cortex?

The primary somatosensory cortex also known as S1 is located on the postcentral gyrus of the parietal lobe in the brain. It plays a crucial role in receiving and processing sensory information from somatic, proprioceptive, and visceral senses. This area composed of the Brodmann areas 1, 2, 3a, and 3breceives inputs related to the touch, pain, body position, and other somatic sensations.

Among the subdivisions within the primary somatosensory cortex area 3 receives the majority of the somatosensory inputs. Area 3b is primarily responsible for the processing of touch sensations. At the same time, area 3a processes information from the proprioceptors which provide feedback on the position and movement of the body parts. Area 3b relays touch information to areas 1 and 2 for further processing. Area 1 is particularly involved in perceiving the texture of objects while Area 2 is responsible for perceiving size shape and proprioception.

Difference Between Primary and Secondary Somatosensory Cortex: The primary somatosensory cortex and the secondary somatosensory cortex have distinct roles. The primary somatosensory cortex primarily handles the reception and processing of sensory information from the somatic senses proprioceptive senses and certain visceral senses. In contrast, the secondary somatosensory cortex is responsible for storing and processing spatial and tactile memory associated with sensory experiences.

The Somatic sensations arise when sensory receptors detect stimuli primarily located in the skin muscles joints and tendons. The somatosensory cortex, comprising different regions plays a crucial role in receiving and processing sensory information from the somatic sensory system. Among these regions, the primary somatosensory cortex receives peripheral sensory information directly while the secondary somatosensory cortex functions to store and further process these inputs.