[UW Anatomy |
Contents]
Function:
Motor control of IPSI. tongue muscles.
Pathway:
Axons of neurons in the hypoglossal nucleus pass ventrally to exit
brainstem between the pyramid and the inferior olive.
Deficits:
Lesion of the hypoglossal nucleus or nerve results in atrophy of the
IPSI. tongue muscles and deviation of the tongue to the IPSI. (weak)
side upon tongue protrusion. Lesion of the corticobulbar fibers to
the hypoglossal nucleus results in CONTRA. deviation of the tongue
upon protrusion (NO ATROPHY).
Other Note:
CORTICOBULBAR PROJECTIONS TO THE HYPOGOSSAL NUCLEUS ARE CROSSED (so
sorry!) LESION OF CORTICOBULBAR FIBERS IS CALLED A SUPRANUCLEAR
LESION (rostral to the nucleus).