Cranial Nerve overview Flashcards
What are the two types of general afferent fibers?
General Somatic Afferents
General Visceral Afferents
General afferent fibers are sensory fibers. Where do we find their cell bodies of origin?
Craniospinal Ganglia
(Dorsal root ganglia; nuclei/ganglia of the specific cranial nerves)
What are the two broad types of impulses that are conducted via general somatic afferents?
Exteroceptive impulses
Proprioceptive impulses
List three examples of exteroceptive impulses.
Where do these impulses originate?
- Pain
- Temperature
- Touch
From epithelium of ectodermal origin
Where do proprioceptive impulses originate from?
Sensory endings in the -
- Body wall
- Tendons
- Joints
What afferent fiber types innervate blood vessels?
GVA
Where are the “special” fiber types found?
Only in the cranial nerves
What are the types of special afferent fibers?
Special Somatic Afferent (SSA)
Special visceral afferent (SVA)
What are SSA’s connected to?
What roles do they function in?
Ear and Eye
Hearing, vision and equilibrium
Where are special visceral afferent fibers found?
What role do they play?
Nose and mouth
Olfactory (smell) and gustatory (taste
Why are SVA’s named as visceral?
Because of the functional association of these sensations with the digestive tract.
What are general efferent fibers?
Motor fibers that innervate the musculature of the body.
What muscles do not recieve general efferent fibers?
branchiomeric muscles
What are the types of general efferent fibers?
General somatic efferent (GSE)
General Visceral Efferent (GVE)
What do GSE’s innervate?
Somatic (skeletal) muscles
What are GVE’s divided into?
Sympathetic and Parasympathetic
What are the two types of special efferent fibers?
Special visceral efferent (SVE)
Special Somatic Efferent (SSE)
What do SVE’s innervate?
Skeletal muscles derived from the visceral (branchiomeric/pharyneal) arch mesoderm
SVE’s innervate muscle derived from branchiomeric/pharyngeal arch mesoderm. What are these muscles involved in?
Mastication, facial expression, pahrynx, palate and larynx
In what way does the autonomic nervous system influence SVE’s?
It does not. The visceral designation has naught to do with autonomics.
What do SSE’s do?
Reflexively influence sensory input to the ear
What cranial nerves carry General somatic efferent fibers?
III
IV
VI
XI
XII
What cranial nerves carry SSE’s?
VIII only
What cranial nerves carry GVE’s?
III
VII
IX
X
What cranial nerves carry SVE’s?
V
VII
IX
X