Internal arcuate fibers come from?
High-Yield Explanation
Ans. D. Nucleus cuneatusDORSAL COLUMN (Fasciculus Gracilis and Fasciculus Cuneatus)a. They carry sensations of conscious proprioception, fine touch, two-point tactile discrimination, and vibration.b. The cell bodies of the first-order sensory neurons lie in the dorsal root ganglia of the spinal nerves. The central processes of these cells enter in the posterior white column as fasciculus gracilis and fasciculus cuneatusc. The fibres of fasciculus gracilis and fasciculus cuneatus terminate in nucleus gracilis and nucleus cuneatus, respectively. The axons of second-order sensory neurons from nucleus gracilis and nucleus cuneatus curve ventromedially around the central grey matter of the medulla as internal arcuate fibres to undergo decussation.d. The fibres after crossing the midline turn upwards as a flat tract called medial lemniscus, which courses upwards to terminate in the ventral posterolateral nucleus (VPL) of the thalamus.e. The third-order sensory neurons from thalamus project into the sensory cortex of the cerebral hemisphere.