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Spinal Cord Tracts The white matter of the spinal cord is divided into the paired posterior (dorsal), lateral, and anterior (ventral) columns. These columns are sometimes called funiculi (or funiculus when singular) and are made up of axons that are traveling up (ascending) or down (descending) the spinal cord. The ascending tracts generally carry sensory information from the periphery to the brain, while the descending tracts carry motor signals to muscles and glands. The columns can be further divided into tracts (sometimes called fasciculi), which is a way of functionally grouping the neurons based on similar origin, destination and function. These tracts are often named for the structures that they connect. For example, the spinothalamic tract indicates that the fibers are carrying information from the spinal cord to the thalamus of the brainstem. You may note from its name that it is an ascending tract, so the information that it carries is sensory. Some of the tracts cross over (decussate) either in the spinal cord or brainstem, and when this occurs, the relationship between the origin and destination is termed contralateral. Much of our motor control is contralateral. For example, the motor area in your left-brain mainly controls your right arm. When the origin and destination of a tract are on the same side of the body, it is referred to as an ispsilateral relationship. Spinal Tracts Tract Column Location Dessusitation location Function Ascending Tracts - Sensory Gracile fasciculus posterior medulla below level T6: limb and trunk position sensations; deep touch; visceral pain; vibration Cuneate fasciculus posterior medulla level T6 and above: limb and trunk position sensations; deep touch; visceral pain; vibration Spinothalamic lateral and anterior spinal cord light touch, tickle, itch, temperature, pain, and pressure sensations Spinoreticular lateral and anterior some fibers of the spinal cord pain sensation from tissue injury Posterior spinocerebellar lateral none proprioception - feedback from muscles Anterior spinocerebellar lateral spinal cord proprioception - feedback from muscles Descending Tracts - Motor Lateral corticospinal lateral medulla fine limb control Anterior corticospinal anterior spinal cord fine limb control Tectospinal anterior midbrain head-turning reflex in response to visual and auditory stimuli Lateral reticulospinal lateral none posture and balance; awareness of pain regulation Medial reticulospinal anterior none posture and balance; awareness of pain regulation Spinal Tracts Lateral vestibulospinal anterior none posture and balance Medial vestibulospinal anterior some fibers of the medulla head position control