Paracentral lobule

Paracentral lobule
Paracentral lobule
	Medial surface of left cerebral hemisphere. (Paracentral lobule is shown in red.)
	Medial view of a halved human brain (Paracentral lobule labeled at top center, in blue.)
Details
Identifiers
Latin	lobulus paracentralis
NeuroNames	1341
TA98	A14.1.09.209
TA2	5466
FMA	77534
	Anatomical terms of neuroanatomy [edit on Wikidata]

In neuroanatomy, the paracentral lobule is on the medial surface of the cerebral hemisphere and is the continuation of the precentral and postcentral gyri. The paracentral lobule controls motor and sensory innervations of the contralateral lower extremity. It is also responsible for control of defecation and urination.

It includes portions of the frontal and parietal lobes:^[1]

The anterior portion of the paracentral lobule is part of the frontal lobe and contains a little portion of Brodmann's area 6 (SMA): this is because the paracentral sulcus (branch of the cingulate sulcus) does not correspond to the precentral sulcus on the medial plane.
The posterior portion is considered part of the parietal lobe and deals with somatosensory of the distal limbs.

While the boundary between the lobes, the central sulcus, is easy to locate on the lateral surface of the cerebral hemispheres, this boundary is often discerned in a cytoarchetectonic manner in cases where the central sulcus is not visible on the medial surface.

Function

Neurons in paracentral lobule are concerned with:

Motor and sensory innervations of the contralateral lower extremity
Regulation of physiological function such as defecation and micturition

Blood supply

It is supplied by branches of the anterior cerebral artery.

Applied anatomy

Damage of paracentral lobule occurs from occlusion of anterior cerebral artery. Characteristic manifestations include:

Contralateral lower limb muscle weakness
Urinary incontinence

Gallery

Animation. Paracentral lobule is shown in red.
Medial view of a human right cerebral hemisphere. Paracentral lobule is labeled at top center, in green.
Medial view of a human right cerebral hemisphere. Paracentral lobule is labeled at top center, in blue.
Cingulate sulcus defines the boundaries of the paracentral lobule.
Marginal sulcus. It defines the posterior boundary of the paracentral lobule.
Paracentral sulcus. It defines the anterior boundary of the paracentral lobule.
Central sulcus on the medial surface. It divides the paracentral lobule into the anterior part and the posterior part.
Paracentral lobule, shown in the right cerebral hemisphere.