Anterior nuclei of thalamus

The anterior nuclei of thalamus form the anterior nuclear group, situated in the rostral part of the thalamus and separated from the medial and lateral nuclear groups by the bifurcation of the Y-shaped internal medullary lamina.

The anterior nuclei of thalamus are important components of the limbic system. They receive prominent input associated with the mammillary bodies, particularly through the mammillothalamic tract, and project to the cingulate cortex. These connections place them within the Papez circuit, linking hippocampal–mammillary pathways with the cingulate region.

Functionally, the anterior thalamic nuclei contribute particularly to learning and episodic memory, with the different subdivisions also participating in aspects of spatial memory and navigation. Damage to this region or interruption of its limbic connections can therefore produce memory impairment.

The anterior nuclei of thalamus also have reciprocal connections with the hypothalamus, the anterior cingulate gyrus (the PAPEZ limbic circuit) and orbitomedial prefrontal cortex. Through their connections with the cingulate gyrus and prefrontal cortex, they controls the emotional tone and executive functions.