The mammillotegmental fasciculus (or mammillotegmental tract, mammillo-tegmental bundle of Gudden, or ''Fasciculus mammillotegmentalis'') is a small bundle of efferent fibers from the hypothalamus running from the

mammillary body The mammillary bodies are a pair of small round bodies, located on the undersurface of the brain that, as part of the diencephalon, form part of the limbic system. They are located at the ends of the anterior arches of the fornix. They consist o ...

to the

tegmentum The tegmentum (from Latin for "covering") is a general area within the brainstem. The tegmentum is the ventral part of the midbrain and the tectum is the dorsal part of the midbrain. It is located between the ventricular system and distinctive ba ...

. Its functions are not well defined for humans, but based on animal studies it seems to be related to regulating visceral function and processing spatial information. The mammillotegmental fasciculus was first described by the German neuroanatomist, Bernhard von Gudden, from which it takes its alternate name, mammillo-tegmental bundle of Gudden. The mammillotegmental fasciculus emerges from the principal mammillary fasciculus of the mammillary body and travels dorsally together with the

mammillothalamic tract The mammillothalamic tract (mammillothalamic fasciculus, thalamomammillary fasciculus, bundle of Vicq d’Azyr) arises from cells in both the medial and lateral nuclei of the mammillary body and by fibers that are directly continued from the for ...

before splitting off and turning caudally to enter the spinal column. There, it terminates in the tegmentum of the

midbrain The midbrain or mesencephalon is the forward-most portion of the brainstem and is associated with vision, hearing, motor control, sleep and wakefulness, arousal (alertness), and temperature regulation. The name comes from the Greek ''mesos'', " ...

at the dorsal and ventral tegmental nuclei and the tegmental pontine reticular nucleus.

References

Hypothalamus Central nervous system pathways {{neuroanatomy-stub