Transcript Lecture 3 - Cranial Nerves - Duke Department of Pathology

Practical Neuroanatomy
Lecture 3
Christine Hulette MD
Cranial Nerves
Auditory System
Visual System
Olfactory and Limbic System
Hypothalamus
Reticular System
SENSORY NERVES
Cranial nerve I Olfactory
Cranial nerve II Optic
Cranial nerve VIII Acoustovestibular
Gertz 1991
MOTOR NERVES
Cranial nerve IV Trochlear
Cranial nerve VI Abducens
Cranial nerve XI Accessory
Cranial nerve XII Hypoglossal
Gertz 1991
Cranial Nerve III Oculomotor
Motor to four eyeball muscles
Parasympathetic to ciliary ganglion
Injury to nerve causes dilated pupil and
ptosis
“fixed and dilated”
Cranial Nerve V Trigeminal
Sensory from face, cornea, mouth, nose,
temporomandibular joint
Motor to muscles of mastication
Cranial Nerve VII Facial
Sensory from anterior 2/3 of tongue
Motor to muscles of facial expression
Parasympathetic to salivary and lacrimal glands
Injury causes facial droop, dry eyes, dry mouth
Cranial Nerve IX Glossopharyngeal
Sensory posterior 1/3 of tongue,
auditory tube, pharynx
Parasympathetic to parotid gland
Cranial Nerve X Vagus
Sensory larynx and pharynx
Motor to larynx and pharynx
Parasympathetic to chest and abdomen
Gertz 1991
AUDITORY SYSTEM
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Outer and Middle ear amplify sound
Inner ear
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Cochlea
Hair cells
Acoustovestibular nerve
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Dorsal and Ventral Cochlear nuclei
Lateral lemniscus
 Inferior colliculus
 Medial geniculate nucleus
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Superior Temporal Cortex
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Brodmann areas 41 and 42
England and Wakely 1991
England and Wakely 1991
England and Wakely 1991
Gertz 1991
VISUAL SYSTEM
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The eyeball focuses light which stimulates the retina.
These signals are transmitted via the optic nerve,
chiasm and tract to the lateral geniculate nucleus in the
thalamus.
Nervous impulses then travel via the optic radiations to
terminate in the primary visual (calcarine) cortex.
www.visionsofjoy.org
England and Wakely 1991
Gertz 1991
Gertz 1991
OLFACTORY SYSTEM
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Sensory receptors in the nasal mucosa are stimulated by
odors.
These stimuli are detected by the olfactory bulb.
Nervous impulses then travel through the olfactory
tract to terminate in the anterior perforated substance.
There are intimate connections with the entorhinal
cortex, amygdala, hippocampus and other parts of the
limbic system.
www.colorado.edu
Gertz 1991
Gertz 1991
Gertz 1991
HYPOTHALAMUS
Bounded by the mamillary bodies, optic chiasm and
hypothalamic sulcus.
Regulates sleep, temperature, water metabolism,
blood pressure, hunger, pituitary hormone secretion.
Sympathetic and parasympathetic balance.
RETICULAR SYSTEM
Descending reticular system projects to autonomic
nervous system, extrapyramidal system output to
voluntary muscles via the pontine tegmentum
Ascending (reticular activating system) provides input
from all sensory organs to thalamus and cortex