CN 7&8 Flashcards
3 nuclei of CN7?
1) motor
2) superiorer salivary nuc= para only
3) nucles of solitary tract= SVA, GSA, GVA
two CN7 roots?
nervous intermedius
motor tract
what nucleus of CN7 wraps around abducens?
motor nucleus
what does nerve to stapedius do?
dampens sound so we don’t harm the hair cells
CN 8 function
sense of hearing, balance, equilibrium, motion
CN 8 functional components
SSA
STATIC LABYRINTH vs KINETIC LABYRINTH
static= Utricle and saccule otolithic organs; Detects the position of the head with respect to gravity; Static movement
kinetic= semicircular ducts; Detects rotational movement of the head; estimation of self-motion, gaze stabilization, and posture balance when moving
-as whole, info comes into vestibular nuclei and then disperses
Utricle vs saccule otolithic organs
Utricle
- Macula utriculi parallel with base of skull
- Senses horizontal acceleration (Car)
saccule
- Macula sacculi vertically oriented
- Senses vertical motion (Elevator)
Bony labyrinth vs Membranous labyrinth in semilunar canals
boney- Contains perilymph
membranous- Contains endolymph
Name the 4 Vestibular nuclei
Superior
Lateral
Medial
Inferior
Neural pathways From vestibular nuclei through/to
Spinal cord
Brainst
Cerebellu
Cerebral cortex
Projections to motor nuclei of CN III, IV, and VI
Vestibulo-Ocular Reflex
Gaze stabilization
Projections to cerebellum
Balance
Compensatory mechanisms to prevent falling over with you walk
Projections to medial vestibulospinal tract
Neck muscle coordination with gaze
Projections to lateral vestibulospinal tract
posture
