Unit 3 Flashcards
Where do cranial nerves attach?
brainstem (midbrain, pons, medulla)
exceptions: CN I and II attach directly to brain, CN XI originates in SC but then enters the spinal cavity
How do cranial nerves enter/exit the cranial cavity?
openings in skull (foramina, meatus, fissures, or canals)
Cranial nerve nuclei
are sensory or motor but NEVER both
Groups of neurons in which sensory fibers terminate OR
Groups of neurons from which motor fibers originate
collection of cell bodies within CNS = nucleus
cranial nerves can have both nuclei and ganglia
3 letter classification scheme of nerve impulses
- G or S; general or special
- S or V; somatic or visceral
- A or E; afferent or efferent
- G or S
general - impulses can be transmitted by cranial OR spinal nerves
special - impulses can ONLY be transmitted by CN
- S or V
somatic - impulses that transmit to skeletal muscle and skin; voluntary transmission
visceral - impulses that transmit to digestive sys, smooth muscle, cardiac muscle, vascular system, and glands; involuntary
- A or E
afferent - impulses transmitted from body to CNS: sensory
efferent - impulses transmitted from CNS to body: motor neurons to skeletal and smooth muscle; secretomotor to glands
GSA
general somatic afferent
sensation from muscles, tendons, joints
GVA
general visceral afferent
sensation from visceral tissues
GSE
general somatic efferent
motor to skeletal muscle
GVE
general visceral efferent
motor to visceral tissues
SSA
special somatic afferent
“special sensations” including vision, audition, and balance
SVA
special visceral afferent
“special sensations” including taste, and olfaction (these ones involve chemical reactions)
SVE
special visceral efferent
motor to “special viscerally-related” skeletal muscles…
Why is SSE not a category?
not special;
considered GSE