In performing any assessment, it is best to do it in a systematic manner. It is also best to know the functions of the organs/systems you will be testing.
For example, the functions of the cranial nerves, in this case.
CN I - Olfactory. Not routinely tested.
CN II - Optic. May use a Snellen chart or mini chart to have the patient read. Pupillary response is also tested here.
CN III - Oculomotor. This is usually tested in conjunction with CN IV and CN VI by moving the eyes through the cardinal directions - start in the midline, and have the patient follow your finger with their eyes while you move it up, then down, then side to side. Any abnormality should be noted. Have the patient open his/her eyes as far as they can. They should be open wide and you should be able to see white above and below the iris.
CN IV - Trochlear. Tested with CN III and VI above.
CN V - Trigeminal. This is a mixed motor and sensory nerve, so you have to test both. Sensory is the corneal reflex, or the skin of the face. Motor is the muscles of mastication. Have the patient clench his/her teeth while feeling over the masseter and temporal muscles for tone and power.
CN VI - Abducens. Tested with CN III and IV above.
CN VII - Facial. Again, a mixed motor and sensory. Motor is the mimetic muscles, or the emotional muscles of the face. Have the patient smile, look for symmetry. Have the patient close his/her eyes tightly. Try to open them. You should not be able to easily. When you had the patient open their eyes very wide for CN III, you should have noticed if their eyebrows went up and their forehead furrowed. It should for normal CN VII function. You can test the taste on the anterior 2/3 of the tongue if you are really interested in testing the sensory function of this nerve.
CN VIII - Vestibulocochlear. A pure sensory nerve. You test this by testing hearing. If you were paying attention during your CN III, IV, and VI tests, you may have noticed some nystagmus. This is normal at the very extremes of lateral gaze and for only a few beats. Any other nystagmus may point to a CN VIII abnormality. Typically, no other tests are performed for the vestibular portion of CN VIII unless there is vertigo present.
CN IX - Glossopharyngeal. Testing this nerve is easy. Gag the patient. If you really want to get fancy, you can test the taste sense on the pharyngeal walls and posterior 1/3 of the tongue. Not usually done, though.
CN X - Vagus. This is the motor function of the gag reflex. Also, listen to the way the patient speaks - are they hoarse or are they phonating normally? If normal, CN X is ok. Have them say, "AHHHHH" while watching their soft palate. Does it rise symmetrically?
CN XI - Spinal accessory. Have the patient turn his/her head against resistance and shrug the shoulders up towards the ears.
CN XII - Hypoglossal. Have the patient stick out their tongue. Is it midline? Move it side to side.
This is a complete (aside from CN I) cranial nerve exam, as well as a brief explanation of what the nerves do.
The cranial nerves exit from the brain inside the cranial cavity.
Cranial nerves #7 (VII) #9 (IX) and #10 (X)
Peripheral nervous system consist of all of the Cranial nerves and Spinal nerves. This division is Anatomical and not Physiological.
Cranial nerves 2 and 3
Somatic sensory nerve impulses get to the brainstem from the head itself via the cranial nerves. Cranial nerves are also known as cerebral nerves.
Cranial Nerves 1-2 Cranial Nerves 3-4 belong to the midbrain. Cranial Nerves 5-8 belong to the pons. Cranial Nerves 9-12 belong to the hindbrain.
How many cranial nerves are there
Because somebody would ask why it wasn't cranial nerves instead of brainial nerves.
yes! there are 12 pairs of cranial nerves
The cranial nerves exit from the brain inside the cranial cavity.
There are 12 pairs of cranial nerves that are part of the PNS. These nerves are sensory, mixed and mostly motor.
Rats have twelve pairs of cranial nerves.
The number of cranial nerves that a cat have is 12. The cranial nerves are mostly located at the cats brain.
The Parasympathetic Division arises from cranial and sacral nerves.
nerves emerging from brain are called cranial nerves.they are 12 pairs
A. Brodal has written: 'The cranial nerves' -- subject(s): Cranial Nerves
There are 12 pairs of cranial nerves, which make a total of 24 cranial nerves. These nerves emerge directly from the brain and are responsible for various sensory, motor, and autonomic functions in the head and neck.