CRANIAL NERVE NUCLEI - LECTURE A

1
CRANIAL NERVE NUCLEI - LECTURE A
NBIO 401 Wednesday, October 3, 2012
2
Objective for the first two cranial nerve
lectures, those about cranial nerve nuclei -Be
able to summarize the function and location of
each cranial nerve nucleus.
3
Cranial Nerve Nuclei Introductory Organization
4
I
II
Optic Nerve
III
V
VI
VII
VIII
IX
X
XII
5
I
II
ONLY III - XII
Optic Nerve
III
V
VI
VII
VIII
IX
X
XII
6
I
CRANIAL NERVE NUCLEI A III - V
II
Optic Nerve
III
V
VI
VII
VIII
IX
X
XII
7
I
II
Optic Nerve
III
V
VI
VII
VIII
IX
X
XII
8
GENERAL SOMATIC CRANIAL NERVE NUCLEI
Sensory GSA and SSA
Motor GSE
Oculomotor III (eye muscles)
Mesencephalic Trigeminal V (jaw muscle spindles)
Main Sensory Trigeminal V (face touch
proprioception)
Trochlear IV (eye muscles)
Vestibular/ Cochlear VIII (vestibular
auditory signals from the inner ear)
Abducens VI (eye muscles)
Spinal Trigeminal V (face pain)
Hypoglossal XII (tongue muscles)
9
GENERAL VISCERAL CRANIAL NERVE NUCLEI
Sensory GVA
Motor GVE
Edinger-Westphal III (constricts pupil -
parasympathetic)
Superior salivatory VII (drives salivary glands -
parasympathetic)
Inferior salivatory IX (drives salivary glands -
parasympathetic)
Solitarius (caudal half) VII, IX, X (sensory
information for autonomic control)
Dorsal motor n. of X (parasympathetic drive
to smooth muscles organs in chest and abdomen)
10
Sensory SVA
Motor SVE
SPECIAL VISCERAL CRANIAL NERVE NUCLEI
Motor Trigeminal V (chewing muscles)
Facial VII (muscles of facial expression)
Solitarius (rostral half) VII, IX, X (taste)
n. Ambiguus IX, X (muscles of the pharynx
larynx)
11
sulcus limitans (divides motor nuclei medial
and sensory nuclei (lateral).
12
sulcus limitans (divides motor nuclei medial
and sensory nuclei (lateral).
13
sulcus limitans
14
Motor nuclei locations
15
General Somatic Efferents lie close to the
midline
16
General Visceral Efferents lay laterally to the
General Somatic Efferents
17
Cranial Nerve Nuclei III-V The Oculomotor
(IIIrd) Nucleus
18
(No Transcript)
19
(No Transcript)
20
Edinger Westphal nucleus (constricts the pupil)
Oculomotor nucleus (motoneurons for eye muscles)
Oculomotor nerve (to eye muscles pupil muscles)
21
General Somatic Efferents lie close to the
midline
22
GENERAL SOMATIC CRANIAL NERVE NUCLEI
Sensory GSA and SSA
Motor GSE
Oculomotor III (eye muscles)
Mesencephalic Trigeminal V (jaw muscle spindles)
Main Sensory Trigeminal V (face touch
proprioception)
Trochlear IV (eye muscles)
Vestibular/ Cochlear VIII (vestibular
auditory signals from the inner ear)
Abducens VI (eye muscles)
Spinal Trigeminal V (face pain)
Hypoglossal XII (tongue muscles)
23
Cranial Nerve Nuclei The Trochlear (IVth) Nucleus
24
Trochlear nerve (to eye muscles)
Trochlear nucleus (motoneurons for eye muscles)
25
General Somatic Efferents lie close to the
midline
26
GENERAL SOMATIC CRANIAL NERVE NUCLEI
Sensory GSA and SSA
Motor GSE
Oculomotor III (eye muscles)
Mesencephalic Trigeminal V (jaw muscle spindles)
Main Sensory Trigeminal V (face touch
proprioception)
Trochlear IV (eye muscles)
Vestibular/ Cochlear VIII (vestibular
auditory signals from the inner ear)
Abducens VI (eye muscles)
Spinal Trigeminal V (face pain)
Hypoglossal XII (tongue muscles)
27
Cranial Nerve Nuclei III-V The Trigeminal Nuclei
28
Mesencephalic trigeminal nucleus (1 sensory
neurons for muscle spindles joint receptors in
head)
To Thalamus
Mesencephalic trigeminal tract (axons bringing
unconscious signals from muscle spindles joints
in head)
Sensory Axons of 1 sensory neuron for
unconscious muscle spindle joint
receptors (cell body in mesencephalic trigeminal
nucleus - the only 1 sensory cell body inside
CNS)
Sensory Axons signals for conscious touch
muscle spindle/joint receptors (cell body in
ganglion outside CNS)
Trigeminal nerve (sensory motor axons of 4
types listed to the right)
Motor Axons carrying motor signals to jaw
muscles (cell body motor trigeminal nucleus)
Sensory Axons signals for pain
temperature (cell body in ganglion outside CNS)
29
Trigeminal nerve (afferent touch, muscle
spindle/joint, pain temperature from
head efferent chewing muscles)
Motor trigeminal nucleus (motoneurons for jaw
muscles)
Main sensory trigeminal nucleus (touch,
conscious spindle joint from head)
Motor trigeminal nucleus
Main sensory trigeminal nucleus
Trigeminal nerve
Spinal trigeminal nucleus
Spinal trigeminal nucleus (pain temperature
from head)
30
Motor Trigeminal Nucleus (right)
Spinal Trigeminal Nucleus (right)
Main sensory trigeminal nucleus (right)
Mesencephalic trigeminal nucleus (left)
Mesencephalic trigeminal tract (left)
Trigeminal Nerve (right)
Spinal trigeminal nucleus (left)
Main sensory trigeminal nucleus (left)
Spinal trigeminal nerve (left) (1 axons on way
to terminate in spinal trigeminal nucleus)
Trigeminal Nerve (left)
31
(No Transcript)
32
(No Transcript)
33
(No Transcript)
34
Special Visceral (Branchial) Efferents lie most
lateral of the motor nuclei.
35
Sensory SVA
Motor SVE
SPECIAL VISCERAL CRANIAL NERVE NUCLEI
Motor Trigeminal V (chewing muscles)
Facial VII (muscles of facial expression)
Solitarius (rostral half) VII, IX, X (taste)
n. Ambiguus IX, X (muscles of the pharynx
larynx)
36
ROSTRAL PONS
Mesencephalic trigeminal tract nucleus
Medial Longitudinal Fasciculus
Superior Cerebellar peduncle
Spinothalamic tract
Medial lemniscus
Pyramidal Tract
Pontine Gray matter
37
Superior cerebellar peduncle
MID PONS
Mesencephalic trigeminal tract nucleus (muscle
spindles from chewing muscles jaw joint
receptors)
Motor trigeminal nucleus
Middle Cerebellar peduncle
MLF
Trigeminal nerve ( sensory motor for the head)
Spinothalamic tract
Medial lemniscus
Pyramidal Tract
Pontine Gray matter
38
Main sensory trigeminal Nucleus (face touch)
Superior cerebellar peduncle (fibers coming out
of cerebellum)
MID PONS
Middle Cerebellar peduncle
Spinal trigeminal tract nucleus
MLF
Motor nucleus of trigeminal (chewing
muscle motoneurons)
Pyramidal Tract
Spinothalamic tract
Medial lemniscus
Pontine Gray matter
39
Facial nerve fibers (looping around abducens
nucleus)
CAUDAL PONS
Abducens Nucleus (eye muscle motoneurons)
Spinal trigeminal nucleus tract
Inferior cerebellar peduncle
Vestibular nuclei
MLF
Facial motor nucleus
Spinothalamic Tract
Middle Cerebellar peduncle
Medial lemniscus
Pyramidal Tract
Pontine Gray matter
40
Cuneate Fasciculus (touch-arm)
Cuneate Nucleus (touch-arm)
Gracile Nucleus (touch-leg)
Gracile Fasciculus (touch-leg)
Central canal
Spinal trigeminal nucleus tract (head pain
temp)
Spinal Accessory Nucleus (motoneurons
for trapezius sternocleidomastoid muscles)
Medial Longitudinal Fasciculus (MLF) (vestibular
oculomotor information)
Spinocerebellar Tract (sensory fibers - Muscle
spindle joint information to cerebellum - leg)
Spinothalamic Tract (body pain)
Pyramidal Decussation (corticospinal
fibers crossing midline)
Pyramids (corticospinal fibers)
41
Fini