Dorsal trigeminothalamic tract

The posterior trigeminothalamic tract (or dorsal trigeminothalamic tract) is composed of second order neuronal axons. These fibers carry sensory information about discriminative touch and conscious proprioception in the oral cavity from the principal (chief sensory) nucleus to the ventral posteromedial (VPM) nucleus of the thalamus.2° (Spinomesencephalic tract → Superior colliculus of Midbrain tectum)2° (Spinomesencephalic tract → Superior colliculus of Midbrain tectum) The posterior trigeminothalamic tract (or dorsal trigeminothalamic tract) is composed of second order neuronal axons. These fibers carry sensory information about discriminative touch and conscious proprioception in the oral cavity from the principal (chief sensory) nucleus to the ventral posteromedial (VPM) nucleus of the thalamus. The posterior trigeminothalamic tract is also called the posterior trigeminal lemniscus. The first order neurons (from the trigeminal ganglion) enter the pons and synapse in the principal (chief sensory) nucleus. Axons of the second order neurons then decussates to enter the trigeminal lemniscus in the midbrain and then ascend to the ventral posteromedial nucleus of the contralateral thalamus, forming the ventral trigeminothalamic tract. A subset of these fibers do not decussate and travel to the ipsilateral ventral posteromedial nucleus of the thalamus. These non-decussating fibers give rise to the dorsal trigeminothalamic tract. The third order neurons in the thalamus ascend to the sensory cortex of the postcentral gyrus.