Cranial Nerves
•Considered Peripheral Nervous System (PNS)
•These peripheral nerves originate from brain.
•Two pairs arise from cerebrum; ten pairs arise from brainstem
•Indicated by
–Roman numerals I-XII from anterior to posterior
–Names
•May have one or more of three functions
–Sensory (special or general)
–Somatic motor (control of skeletal muscles)
–Parasympathetic (regulation of glands, smooth muscles, cardiac muscle)
Cranial Nerve Reflexes
•X (Vagus): reflexes having to do with heart rate, blood pressure, and respiration
•Reflexes involving both cranial nerves and brainstem:
–Turning the eyes toward sudden noise, touch on skin, flash of light
–Eyes tracking a moving object.
–Reflex using VIII, V, and VII to contract muscles associated with middle ear that protect ear ossicles
–Chewing reactions to textures of food, movement of tongue pushing food under tooth-row and out of harm's way
Trigeminal Nerve
