What Is the Posterior Cingulate?

The cingulate is located near the middle of the brain's cortex. Its posterior, the posterior cingulate, also forms the upper limbic lobe. Scientists have proposed that the posterior cingulate plays a role in human awareness, memory retrieval and pain recognition. The exact function of the region, however, has yet to be proved.

There are four parts to the brain, with the forebrain at its front. Contained within the forebrain are the cerebrum and a section of the limbic system. The cerebrum contains four lobes and is involved in higher brain functions. Reasoning, movement and sensory perception are all related to the cerebrum.

Beneath the cerebrum, and flanking the thalamus, is the limbic system. The primary components of the limbic system are the hippocampus and hypothalamus. Regulating the emotional and physiological responses of the body is the job of the hypothalamus. The hippocampus converts short-term memory to long-term memory.

Close by the limbic system in the cerebrum is the cingulate. The cingulate provides a communication pathway between the hypothalamus and the thalamus, which passes sensations and motor signals to the cerebral cortex. Two sections comprise the cingulate, the anterior cingulate and the posterior cingulate.

The anterior cingulate is tied to obsessive thoughts and behavior. Taken to the extreme, this can lead to conditions such as obsessive compulsive disorder (OCD) and anxiety disorders. Problems in the anterior cingulate might cause Tourette's syndrome or chronic pain conditions. More is known about the anterior cingulate than the posterior cingulate.

The posterior cingulate is centrally located along the default mode network (DMN) that controls the brain when the body and mind are at rest. Brain scans have shown that the nerves of the posterior cingulate cease firing while a person performs a task but reactivate when the task is completed. This suggests that the region is decreasing its connection to the DMN while the task is performed. Its connection to the cognitive control network (CCN) moves in the opposite direction, increasing with a task but decreasing while at rest.

Little is known about the exact function of the posterior cingulated. Scientific papers have suggested numerous functions. Ideas include sleep regulation, feelings of loneliness and political beliefs. There is not enough evidence, however, to conclusively define the region.

Atrophy of the posterior cingulate might correlate to Alzheimer's disease. Research involving individuals who have the disease has shown that the cingulate region in general is notably smaller. The posterior cingulate was found to be nearly half its proper size.