[5] They are connected to other parts of the brain (as shown in the schematic, below left), and act as a relay for impulses coming from the amygdalae and hippocampi, via the mamillothalamic tract to the thalamus.

[6] Mammillary bodies, and their projections to the anterior thalamus via the mammillothalamic tract, are important for recollective memory.

[7] Damage to the mammillary bodies due to thiamine deficiency is implied in pathogenesis of Wernicke–Korsakoff syndrome.

[8] Mammillary body atrophy is present in several other conditions, such as colloid cysts in the third ventricle, Alzheimer's disease, schizophrenia, heart failure, and sleep apnea.

In spite of this the exact function of the mammillary bodies is still not clear.