Cranial nerves

TESTING CRANIAL NERVES ACTIVITY SHEET
Purpose:
This activity is designed to help the student become familiar with the functions of the Cranial Nerves. Perform each test on your lab partner. Carefully observe and record the results of each test. (Do not perform a test if a medical condition is present that may be exacerbated by the test.)
Background:
Materials:
Two different items to smell.A newspaper or other printed material.
Penlight
Cotton ball
Cotton applicator
Sugar solution
Ticking watch
Lemon
Tongue depressor
Gloves
Goggles
Biohazard containers
Surface disinfectant
Paper towels
Procedure:
1. Preparation
Wash hands and put on gloves and goggles.
Assemble equipment and materials.
Prepare work area.

2. Olfactory I
Equipment: At least two differentitems to smell.
Procedure: Have your lab partner close both eyes and plug one nostril.
Hold a familiar smell under the open nostril and ask him/her to identify it. Test the other nostril with a different smell.


3. Optic II
Equipment: Newspaper or other printed material.
Procedure: Ask your lab partner to cover one eye. Hold the
printed material approximately 18 inches away and have themread two sentences. Repeat the procedure using the other eye.

Peripheral vision is tested as you stand or sit two feet in front
of your lab partner. Your eyes should be at the same level as theirs. Ask your partner to cover their right eye. You should cover your left eye. (Your field of vision should be similar.) Extend your right arm to the side, raise your forefinger and position it aboutthe same distance from your face and your partner’s. Your partner should let you know when he/she sees your finger. Now, wiggle your finger and slowly move it inward. Your lab partner should see your finger about the same way you do.

4. Oculomotor III, Trochlear IV, and Abducens VI
(These Nerves are usually tested together.)
Equipment: Penlight
Procedure: To check for extraocular musclemovement, hold your
forefinger about 18 inches away form your partner’s eyes. Ask your partner to follow your finger with his/her eyes as you draw the letter “H”. Your partner’s eyes should move together as they follow your finger with their eyes. Their head should not move.

Shine the penlight into your partner’s eye from
approximately 8 inches away. Pupil should constrict immediately. Repeatwith other eye.

5. Trigeminal V
Equipment: Cotton ball, ice, two different smells
Procedure: To evaluate the strength and symmetry of the temporal
muscles, put your fingertips on your lab partner’s temples and ask him/her to clench his/her teeth. To assess the masseter muscles, place your fingertips on his/her jaw and ask them to clench their teeth. The muscles should feel strong and evenon both sides of their head and face.

To test for the sensory function (ophthalmic, maxillary, and
mandibular sensations). First have your partner close both eyes. Lightly touch his/her forehead, cheek, and jaw, on both sides of the face, using a cotton ball. Have them tell you when they feel the cotton touching them.

To test for the sensory function (ophthalmic, maxillary, and
mandibularsensations). First have your partner close both eyes. Lightly touch his/her forehead, cheek, and jaw, on both sides of the face, using a cotton ball. Have them tell you when they feel the cotton touching them. Second, take a small piece of ice and apply it briefly to a maxillary and a mandibular incisor.


Have your partner close their eyes and take three strong sniffs from two different items.Your partner should explain how they are different or how they are the same. (Some chemicals produce a cooling or irritating sensation in the nasal cavity by stimulating the Trigeminal nerve.)


6. Facial VII
Equipment: Cotton applicator and sugar solution
Procedure: Assess the taste buds by touching a cotton applicator dipped in
a sugar solution on to the tongue of your lab partner....