postcentralisella

The postcentralisella, more commonly referred to as the postcentral gyrus or gyrus postcentralis, is a prominent fold of the cerebral cortex located in the parietal lobe. It lies immediately posterior to the central sulcus on the lateral surface of each hemisphere and corresponds to the primary somatosensory cortex. In humans, it encompasses areas that map to Brodmann areas 3, 1, and 2.

Functionally, the postcentral gyrus receives and processes somatosensory information from the contralateral side of the body. Afferent input reaches S1 primarily from thalamic nuclei, especially the ventral posterolateral (VPL) and ventral posteromedial (VPM) nuclei. The cortex contributes to the perception of touch, proprioception, temperature, and nociception, and supports higher-level sensory functions such as texture discrimination and stereognosis. The region is organized somatotopically, producing a sensory homunculus in which body parts with higher tactile acuity—such as the lips, face, and hands—occupy larger cortical areas.

Anatomically, the postcentral gyrus communicates with the secondary somatosensory cortex and parietal association areas, forming part of sensorimotor integration networks. It receives input from and sends outputs to multiple cortical and thalamic regions, facilitating perception and coordinated responses to sensory stimuli.

Clinical significance centers on sensory deficits from focal lesions. Damage to the postcentral gyrus typically causes contralateral sensory loss, including impaired tactile discrimination and proprioception, possible astereognosis, and sometimes sensory neglect when the dominant or non-dominant parietal regions are affected. Vascular events, such as strokes in the middle cerebral artery territory, frequently involve this region.