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What is Nucleus gracilis and Nucleus cuneatus are the first synapses for and explain in detail?
(A) Dorsal columns > Primary afferent neurons are located in dorsal root ganglion cells, and fibers (group II) ascend ipsilaterally and coalesce in the fasciculus gracilis or fasciculus cuneatus.> And these two fasciculi form the dorsal columns of the spinal cord and ascend the length of the spinal cord to nucleus gracilis and nucleus cuneatus of the medulla.> The Fasciculus gracilis consists of fibres from sacral and lumbar region and Fasciculus cuneatus receives its fibres from thoracic and cervical.