The Spinothalamic Tracts
These tracts carry conscious pain, temperature, crude touch, and pressure. There is a lateral and an anterior tract. They carry this information first to the thalamus of the brain which receives all conscious sensations, and then terminate in the areas of the cerebral cortex which perceive these sensations.
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The Spinocerebellar Tract
This tract carries unconscious proprioception (muscle sense) to the cerebellum which is responsible for muscle coordination. The fibers either do not cross, or cross and recross so that they innervate the cerebellum on the same side.
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The Fasciculus Gracilis and Fasciculus Cuneatus
These tracts carry discriminative touch (the gracilis) and conscious proprioception (the cuneatus). Discriminative touch allows you to specifically localize the location whereas crude touch does not. The fibers of these tracts go first to the medulla where they synapse and cross. Then through a pathway called the medial lemniscus they pass to the thalamus. Then on to the cerebral cortex for perception.
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The Corticospinal Tract
The corticospinal tract originates in the cerebral cortex where voluntary motor control is localized. There are two branches, the lateral and the anterior. The lateral crosses in the medulla in an area known due to its appearance as the pyramids. The anterior does not cross. These fibers are called "upper motor neurons" and they synapse with "lower" motor neurons in the cord which lead to the skeletal muscles.
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