Long description

On the left and on the right are drawings of a sagittal section of the brain and upper spinal cord. In the centre is a drawing of the lungs with trachea and bronchi / bronchioles.

Sensory neurons from the trachea pass to the T1 segment of the spinal cord (shown in blue on the left-hand diagram). Sensory neurons from the lungs pass, via the pulmonary plexus, to segments T2, T3 and T4 of the spinal cord (all shown in blue, as are the cell bodies of the sensory neurons outside of the spinal cord).

Motor neurons (shown as purple lines) from centres (shown as a purple dot) at the base of the medulla oblongata (shown in the right-hand diagram) pass to the lungs – these form fibres in the vagus nerve (cranial nerve X).