What does the fasciculus gracilis contain?

• A. Axons from the legs and lower body
• B. Axons from upper body
• C. Axons from brainstem
• D. Motor commands to limbs

Answer: (A)

The main idea here is that the dorsal column–medial lemniscus system is split into two tracts that carry similar sensory information from different body regions. The fasciculus gracilis contains axons carrying fine touch, vibration, and conscious proprioception from the legs and lower body. It runs medially in the dorsal columns and ascends to the nucleus gracilis in the lower part of the medulla, where it synapses before continuing to the thalamus. In contrast, fibers from the upper body travel in the neighboring fasciculus cuneatus. Motor commands to limbs, meanwhile, travel via the corticospinal tract, not the dorsal columns. So the correct choice is that it contains axons from the legs and lower body.