Organ
Postcentral gyrus
The cortical representation of somatic sensation
High-yield
VPL carries body somatosensory information and VPM carries facial somatosensory information to this region. VPM-associated taste pathways instead principally reach gustatory cortex in the insular and opercular region.
Overview
Behind the central sulcus, the postcentral region contains somatosensory areas 3a, 3b, 1 and 2. Thalamic input comes principally from VPL for the body and VPM for the face. Separate, overlapping body maps emphasize the hands and face; lower-limb representation extends medially into the paracentral lobule.
Reference facts
- Location
- Between central and postcentral sulci in the anterior parietal lobe, continuing medially into posterior paracentral cortex.
- Parts
- Somatosensory areas 3a, 3b, 1 and 2. Areas 5 and 7 lie farther posteriorly and contribute to sensory association functions.
- Blood supply
- MCA supply to the lateral surface and ACA supply to the medial lower-limb region.
- Relations
- Thalamocortical fibers reach it through the posterior internal capsule and corona radiata; adjacent precentral cortex is across the central sulcus.
- Function
- Helps localize and discriminate bodily sensations, including touch and position, and contributes to wider cortical processing of pain and temperature.
Clinical correlation
A lesion can reduce opposite-sided sensory discrimination, such as recognizing an object by touch or distinguishing nearby touch points. The pattern depends on the cortical area and extent of damage; basic touch or pain can also be affected, so preserved crude sensation is not required.
Frequently asked questions
Where is the postcentral gyrus located?
Between central and postcentral sulci in the anterior parietal lobe, continuing medially into posterior paracentral cortex.
What does the postcentral gyrus do?
Helps localize and discriminate bodily sensations, including touch and position, and contributes to wider cortical processing of pain and temperature.
What are the parts of the postcentral gyrus?
Somatosensory areas 3a, 3b, 1 and 2. Areas 5 and 7 lie farther posteriorly and contribute to sensory association functions.
What is the blood supply of the postcentral gyrus?
The postcentral gyrus is supplied by the MCA supply to the lateral surface and ACA supply to the medial lower-limb region.