Anterior spinothalamic tract
The anterior spinothalamic tract, also known as the ventral spinothalamic fasciculus, is an ascending pathway located anteriorly within the spinal cord, primarily responsible for transmitting coarse touch and pressure.
The lateral spinothalamic tract (discussed separately), in contrast, primarily transmits pain and temperature.
Gross anatomy
Peripheral connections
First-order neurons, whose cell bodies are in the dorsal root ganglion and whose axons extend from peripheral receptors, enter the cord via dorsal nerve roots.
Central course
The aforementioned first-order neurons synapse with second-order neurons whose bodies are located in the ipsilateral dorsal horn of the cord. In contrast to the lateral spinothalamic tract, whose fibers decussate almost immediately, these second-order neurons' axons ascend a few levels before crossing via the anterior spinal commissure and form the anterior spinothalamic tract .
The anterior spinothalamic tract lies in the anterior funiculus, medial to where the ventral spinal roots exit. It overlaps the vestibulospinal tract. Fibers of this tract are somatotopically organized for their entire course.
Upon reaching the brainstem, the anterior and lateral spinothalamic tracts combine to form the spinal lemniscus, which runs lateral to the medial lemniscus. The spinal lemniscus terminates in the ventral posterior nucleus of the thalamus. Here, it synapses with third-order neurons, which project to the primary somatosensory area on the ipsilateral side of the cerebral cortex.