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• Field trip forms must be turned in by Friday if you want to go.

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• After Ms. Lorete finishes teaching you the name and function of the 12 pairs of cranial nerves there is an oral quiz worth 1/3 of a test grade.

• If you do not complete the quiz in class today the quiz Tuesday is much harder

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Nervous System II: Cranial Nerves

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• Cranial nerves are part of the peripheral nervous system.

• Carry sensory or motor information or a combination and function in parasympathetic nervous system.

• Cranial nerves I, II, VIII are purely sensory.• Cranial nerves III, IV, VI, XI and XII are motor

(although also function balance).

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Cranial Nerves• Indicated by Roman

numerals I-XII from anterior to posterior

• May have one or more of 3 functions– Sensory (special or

general)– Motor (skeletal muscles) – Parasympathetic

(regulation of glands, smooth muscles, cardiac muscle)

• Balance– Positional information of

body parts

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Cranial Nerves

• Olfactory (I)• Optic (II)• Oculomotor (III)• Trochlear (IV)• Trigeminal (V)• Abducens (VI)• Facial (VII)

• Vestibulocochlear (VIII)– Also known as auditory

• Glossopharyngeal (IX)• Vagus (X)• Accessory (XI)

– Also known as spinal accessory

• Hypoglossal (XII)

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Mnemonic Aids for Cranial Nerves

• To remember at least part of the sequence of the first set of cranial nerves that begin with the letter O, try this –You have I nose. You have II eyes.I - Olfactory; II -- Optic

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Mnemonic Aids for Cranial Nerves

• On Old Olympus Towering Tops A Famous Vocal German Viewed Some Hops

• Olfactory, Optic, Oculomotor, Trochlear, Trigeminal, Abducens, Facial, Vestibulocochlear, Glossopharyngeal, Vagus, Spinal Accessory (Accessory), Hypoglossal

• Oh. Oh. Ooh...To Touch And Feel Very Green Vegetables...A H !!!• Oh, once one takes the anatomy final- very good vacations are heavenly!

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Cranial Nerves• Olfactory (I)

– Sensory (smell)

• Optic (II)– Sensory (sight)

• Oculomotor (III)– Motor (4 of 6 eye muscles)

– Parasympathetic (constriction of pupil, movement of lens)

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Cranial Nerves• Trochlear (IV)

– Visual tracking of eye

• Trigeminal (V)– Sensory (face, nasal cavity, cheeks, lips, skin of mandible)–Motor (muscles of mastication, anterior belly of digastric, mylohyoid)

• Abducens (VI)– Motor (1 eye muscle)

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Cranial Nerves• Facial (VII)

– Sensory (taste)– Motor (facial muscles,

posterior belly of digastric)

– Parasympathetic (salivary glands, glands of nasal cavity)

• Vestibulocochlear (VIII)– Sensory (hearing and balance)

• Glossopharyngeal (IX)– Sensory (taste, back of mouth, tonsils, middle ear)– Motor (1 muscle of pharynx)– Parasympathetic (salivary gland, glands of tongue)

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Cranial Nerves• Vagus (X)

– Sensory (taste, back of mouth, larynx, thoracic and abdominal organs)

– Motor (muscles of larynx, 1 muscle of tongue)

– Parasympathetic (thoracic and abdominal organs)

• Accessory (XI)– Motor (sternocleidomastoid, trapezius)

• Hypoglossal (XII)– Motor (tongue and throat muscles)

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I Olfactory

• Functions in the special sense of smell or olfaction.

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II Optic

• Visual information enters the eye in the form of photons of light which are converted to electrical signals in the retina. These signals are carried via the optic nerves, chiasm, and tract to the lateral geniculate nucleus of each thalamus and then to the visual centers of the brain for interpretation.

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III Occulomotor

• The somatic motor component, plays a major role in controlling the muscles responsible for the precise movement of the eyes for visual tracking or fixation on an object.

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IV Trochlear

• The superior oblique muscle is one of the six extraocular muscles responsible for the precise movement of the eye for visual tracking or fixation on an object.

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V Trigeminal Nerve

• Sensory information from the face and body is processed by parallel pathways in the central nervous system.

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VI Abducens

• The lateral rectus muscle is one of the six extraocular muscles responsible for the precise movement of the eye for visual tracking or fixation on an object.

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VII Facial Nerve

• Supplies the muscles of facial expression

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VIII Vestibulocochlear Nerve

• responsible for transmitting sound and equilibrium (balance)

• AKA Acoustic nerve

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IX Glossopharyngeal

• Innervates the muscle that allows you to swallow

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X Vagus

• The vagus nerve is the longest of the cranial nerve. Its name is derived from Latin meaning "wandering".

• The vagus nerve helps to regulate the heart beat, control muscle movement, keep a person breathing, and to transmit a variety of chemicals through the body

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XI Accessory

• Innervates the trapezius and sternocleidomastoid muscles.

• Shrug your shoulders

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XII Hypoglossal

• Movement of the tongue