Practical NeuroanatomyPractical NeuroanatomyLecture 3Lecture 3

Christine Hulette MDChristine Hulette MD

Practical NeuroanatomyPractical NeuroanatomyLecture 3Lecture 3

Christine Hulette MDChristine Hulette MD

Cranial NervesCranial NervesAuditory SystemAuditory System

Visual SystemVisual SystemOlfactory and Limbic SystemOlfactory and Limbic System

Hypothalamus Hypothalamus Reticular SystemReticular System

SENSORY NERVESSENSORY NERVESSENSORY NERVESSENSORY NERVES

Cranial nerve I OlfactoryCranial nerve I Olfactory

Cranial nerve II OpticCranial nerve II Optic

Cranial nerve VIII AcoustovestibularCranial nerve VIII Acoustovestibular

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MOTOR NERVESMOTOR NERVESMOTOR NERVESMOTOR NERVES

Cranial nerve IV TrochlearCranial nerve IV Trochlear

Cranial nerve VI AbducensCranial nerve VI Abducens

Cranial nerve XI AccessoryCranial nerve XI Accessory

Cranial nerve XII HypoglossalCranial nerve XII Hypoglossal

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Cranial Nerve III OculomotorCranial Nerve III OculomotorCranial Nerve III OculomotorCranial Nerve III Oculomotor

Motor to four eyeball musclesMotor to four eyeball muscles

Parasympathetic to ciliary ganglionParasympathetic to ciliary ganglion

Injury to nerve causes dilated pupil and Injury to nerve causes dilated pupil and ptosisptosis

““fixed and dilated”fixed and dilated”

Cranial Nerve V TrigeminalCranial Nerve V TrigeminalCranial Nerve V TrigeminalCranial Nerve V Trigeminal

Sensory from face, cornea, mouth, nose, Sensory from face, cornea, mouth, nose, temporomandibular jointtemporomandibular joint

Motor to muscles of masticationMotor to muscles of mastication

Cranial Nerve VII FacialCranial Nerve VII FacialCranial Nerve VII FacialCranial Nerve VII Facial

Sensory from anterior 2/3 of tongueSensory from anterior 2/3 of tongue

Motor to muscles of facial expressionMotor to muscles of facial expression

Parasympathetic to salivary and lacrimal glandsParasympathetic to salivary and lacrimal glands

Injury causes facial droop, dry eyes, dry mouthInjury causes facial droop, dry eyes, dry mouth

Cranial Nerve IX GlossopharyngealCranial Nerve IX GlossopharyngealCranial Nerve IX GlossopharyngealCranial Nerve IX Glossopharyngeal

Sensory posterior 1/3 of tongue, Sensory posterior 1/3 of tongue, auditory tube, pharynxauditory tube, pharynx

Parasympathetic to parotid glandParasympathetic to parotid gland

Cranial Nerve X VagusCranial Nerve X VagusCranial Nerve X VagusCranial Nerve X Vagus

Sensory larynx and pharynxSensory larynx and pharynx

Motor to larynx and pharynxMotor to larynx and pharynx

Parasympathetic to chest and abdomenParasympathetic to chest and abdomen

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AUDITORY SYSTEMAUDITORY SYSTEMAUDITORY SYSTEMAUDITORY SYSTEM Outer and Middle ear amplify soundOuter and Middle ear amplify sound Inner earInner ear

CochleaCochlea Hair cellsHair cells

Acoustovestibular nerveAcoustovestibular nerve Dorsal and Ventral Cochlear nucleiDorsal and Ventral Cochlear nuclei

Lateral lemniscusLateral lemniscus Inferior colliculusInferior colliculus Medial geniculate nucleusMedial geniculate nucleus

Superior Temporal CortexSuperior Temporal Cortex Brodmann areas 41 and 42Brodmann areas 41 and 42

England and Wakely 1991England and Wakely 1991England and Wakely 1991England and Wakely 1991

England and Wakely 1991England and Wakely 1991England and Wakely 1991England and Wakely 1991

England and Wakely 1991England and Wakely 1991England and Wakely 1991England and Wakely 1991

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VISUAL SYSTEMVISUAL SYSTEMVISUAL SYSTEMVISUAL SYSTEM

The eyeball focuses light which stimulates the retina.The eyeball focuses light which stimulates the retina. These signals are transmitted via the optic nerve, These signals are transmitted via the optic nerve,

chiasm and tract to the lateral geniculate nucleus in the chiasm and tract to the lateral geniculate nucleus in the thalamus.thalamus.

Nervous impulses then travel via the optic radiations to Nervous impulses then travel via the optic radiations to terminate in the primary visual (calcarine) cortex.terminate in the primary visual (calcarine) cortex.

www.visionsofjoy.orgwww.visionsofjoy.orgwww.visionsofjoy.orgwww.visionsofjoy.org

England and Wakely 1991England and Wakely 1991England and Wakely 1991England and Wakely 1991

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OLFACTORY SYSTEMOLFACTORY SYSTEMOLFACTORY SYSTEMOLFACTORY SYSTEM

Sensory receptors in the nasal mucosa are stimulated by Sensory receptors in the nasal mucosa are stimulated by odors.odors.

These stimuli are detected by the olfactory bulb.These stimuli are detected by the olfactory bulb. Nervous impulses then travel through the olfactory Nervous impulses then travel through the olfactory

tract to terminate in the anterior perforated substance.tract to terminate in the anterior perforated substance. There are intimate connections with the entorhinal There are intimate connections with the entorhinal

cortex, amygdala, hippocampus and other parts of the cortex, amygdala, hippocampus and other parts of the limbic system.limbic system.

www.colorado.eduwww.colorado.eduwww.colorado.eduwww.colorado.edu

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HYPOTHALAMUSHYPOTHALAMUSHYPOTHALAMUSHYPOTHALAMUS

Bounded by the mamillary bodies, optic chiasm and Bounded by the mamillary bodies, optic chiasm and hypothalamic sulcus.hypothalamic sulcus.

Regulates sleep, temperature, water metabolism, Regulates sleep, temperature, water metabolism, blood pressure, hunger, pituitary hormone secretion.blood pressure, hunger, pituitary hormone secretion.

Sympathetic and parasympathetic balance.Sympathetic and parasympathetic balance.

RETICULAR SYSTEMRETICULAR SYSTEMRETICULAR SYSTEMRETICULAR SYSTEM

Descending reticular system projects to autonomic Descending reticular system projects to autonomic nervous system, extrapyramidal system output to nervous system, extrapyramidal system output to

voluntary muscles via the pontine tegmentumvoluntary muscles via the pontine tegmentum

Ascending (reticular activating system) provides input Ascending (reticular activating system) provides input from all sensory organs to thalamus and cortexfrom all sensory organs to thalamus and cortex