Nucleus gracilis and Nucleus cuneatus are the first synapses for
(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.
Dorsal columns
Ventral spinothalamic tract
Dorsa lateral tract
Lateral spinothalamic tract
Nervous System