- Cranial Nerves 5, 7, 9, 10 229
DRAWING 13-8 Th e Gag Refl e x
THE GAG REFLEX
Sensory Loop
(WEAK)
(STRONG) (WEAK)
Motor Loop
Soft palate
stimulus
CrN 9 Spinal trigeminal
nucleus or
Solitary tract
nucleus
Nucleus ambiguus
Motor trigeminal
nucleus
Hypoglossal nucleus
Pharyngeal
constriction
Jaw opening
Tongue thrust
CrN 10
CrN 5
CrN 12
Nucleus ambig.
Cortico
nuclear
Palate
(STRONG)
NORMAL
CORTICONUCLEAR
INNERVATION
Upper motor
neuron injury
Lower motor neuron injury