Tractus spinothalamicus anterior

The anterior spinothalamic tract, (Latin: tractus spinothalamicus anterior) or ventral spinothalamic fasciculus situated in the marginal part of the anterior funiculus and intermingled more or less with the vestibulospinal tract, is derived from cells in the posterior column or intermediate gray matter of the opposite side.

Aβ fibres carry sensory information pertaining to crude touch from the skin.

After entering the spinal cord the first order neurons synapse (in the nucleus proprius), and the second order neurons decussate via the anterior white commissure.

These second order neurons ascend synapsing in the VPL of the thalamus.

Incoming first order neurons can ascend or descend via the Lissauer tract.

This is a somewhat doubtful fasciculus and its fibers are supposed to end in the thalamus and to conduct certain of the touch impulses. More specifically, its fibers convey crude touch information to the VPL (ventral posterolateral nucleus) part of the thalamus.

The fibers of the anterior spinothalamic tract conduct information about pressure and crude touch (protopathic).

The fine touch (epicritic) is conducted by fibers of the medial lemniscus.

The medial lemniscus is formed by the axons of the neurons of the gracilis and cuneatus nuclei of the medulla oblongata which receive information about light touch, vibration and conscient proprioception from the gracilis and cuneatus fasciculus of the spinal cord.

This fasciculus receive the axons of the first order neuron which is located in the dorsal root ganglion that receives afferent fibers from receptors in the skin, muscles and joints.