Trigeminal lemniscus

The trigeminal lemniscus, also called the trigeminothalamic tract, is a part of the brain that conveys tactile, pain, and temperature impulses from the skin of the face, the mucous membranes of the nasal and oral cavities, and the eye, as well as proprioceptive information from the facial and masticatory muscles.

The trigeminal lemniscus is composed of second order neuronal axons in the brainsteam. It carries sensory information from the trigeminal system to the ventral posteromedial (VPM) nucleus of the thalamus.

This tract was historically considered a cephalic division of the medial lemniscus due to the close proximity of the two ascending tracts. Like the dorsal column medial lemniscus (DCLM) system, the trigeminal lemniscus carries tactile and proprioceptive sensations. However, the trigeminal lemniscus also carries pain and temperature sensations from the contralateral orofacial region, just as the spinothalamic pathway carries these sensations from the contralateral body. Thus, the trigeminal lemniscus of the head is functionally analogous to both the DCLM and spinothalamic systems of the body.