Mammillary body

Anatomy

The mammillary bodies are a pair of small round bodies, located on the undersurface of the brain that form part of the limbic system, which is involved in the processing of recognition memory. They are located at the ends of the anterior arches of the fornix, and consist of two groups of nuclei, the medial mammillary nuclei and the lateral mammillary nuclei.

Function

The mammillary bodies and their connections within the brain help in the relay of signals in the brain, particularly signals related to memory. They receive signals from the hippocampus via the fornix and project to the thalamus, which then sends signals to the cortex. This pathway is thought to be involved in the modulation and control of memory.

Clinical significance

Damage to the mammillary bodies can result in memory deficits, particularly in the recall of episodic memory. This is seen in Wernicke-Korsakoff syndrome, a neurological disorder often associated with chronic alcohol abuse, where there is damage to the mammillary bodies and other regions of the brain involved in memory.

History

The mammillary bodies were first described by the ancient Greeks, who named them after their resemblance to small breasts (mammillae). Over the centuries, their function remained a mystery until the 20th century when advances in neuroanatomy and neurophysiology revealed their role in memory processing.

See Also

• Hippocampus
• Thalamus
• Wernicke-Korsakoff syndrome