Spinal lemniscus

The spinal lemniscus consists of a collection of white matter tracts situated in the lateral region of the brainstem. This bundle includes three key spinal pathways: the lateral spinothalamic tract, the anterior spinothalamic tract, and the spinotectal pathway.

The lateral spinothalamic tract is involved in transmitting pain and temperature sensations from different areas of the body. In contrast, the anterior spinothalamic tract carries sensations of light touch and pressure. Both pathways travel up through the lateral part of the brainstem as components of the spinal lemniscus, eventually relaying this sensory information to the thalamus.

The spinotectal tract originates from the cervical segment of the spinal cord and ends by synapsing with the superior colliculus in the midbrain. It ascends through the brainstem alongside the spinothalamic tracts, forming part of the spinal lemniscus. This pathway provides sensory input necessary for spinovisual reflexes, enabling the eyes and head to move toward stimuli sources.