The trochlear nerve is the fourth paired cranial nerve. It is the smallest cranial nerve (by number of axons), yet has the longest intracranial course.
Which is the smallest nerve in human body?
The trochlear nerve is unique among the cranial nerves in several respects: It is the smallest nerve in terms of the number of axons it contains. It has the greatest intracranial length. It is the only cranial nerve that exits from the dorsal (rear) aspect of the brainstem.
Which is the largest cranial nerve?
The trigeminal nerve is the largest of your cranial nerves and has both sensory and motor functions. The trigeminal nerve has three divisions, which are: Ophthalmic. The ophthalmic division sends sensory information from the upper part of your face, including your forehead, scalp, and upper eyelids.
What is the fattest cranial nerve?
The trigeminal nerve is the largest cranial nerve and is the great sensory nerve of the head and face, and the motor nerve of the muscles of mastication.
What is cranial nerve 1 called?
Cranial Nerves
| Number | Name | Function |
|---|---|---|
| I | Olfactory Nerve | Smell |
| II | Optic Nerve | Vision |
| III | Oculomotor Nerve | Eye movement; pupil constriction |
| IV | Trochlear Nerve | Eye movement |
What’s the biggest nerve in your body?
The sciatic nerve is the largest nerve in the human body.
Do you have nerves in your brain?
Nerves that directly connect the brain and the brain stem with the eyes, ears, nose, and throat and with various parts of the head, neck, and trunk are called cranial nerves. There are 12 pairs of them (see Overview of the Cranial Nerves).
Which is the thinnest cranial nerve?
The trochlear nerve is the longest and thinnest of all cranial nerves, making it susceptible to trauma. After leaving the trochlear nucleus, the axons pass dorsolaterally and caudally around the periaquaeductal gray, and decussate almost completely in the anterior medullary velum.
Which is the thickest cranial nerve?
The largest cranial nerve is trigeminal nerve. The smallest cranial nerve is abducens nerve. The thinnest cranial nerve is trochlear nerve.
What is the most important cranial nerve?
Medical Definition of Tenth cranial nerve
Tenth cranial nerve: The tenth cranial nerve, and one of the most important, is the vagus nerve. All twelve of the cranial nerves, the vagus nerve included, emerge from or enter the skull (the cranium), as opposed to the spinal nerves which emerge from the vertebral column.
How do you test for cranial nerve 10?
The motor division of CN 9 & 10 is tested by having the patient say “ah” or “kah”. The palate should rise symmetrically and there should be little nasal air escape. With unilateral weakness the uvula will deviate toward the normal side because that side of the palate is pulled up higher.
How do you test cranial nerve function?
Light touch is tested in each of the three divisions of the trigeminal nerve and on each side of the face using a cotton wisp or tissue paper. The ophthalmic division is tested by touching the forehead, the maxillary division is tested by touching the cheeks, and the mandibular division is tested by touching the chin.
Which is the sixth cranial nerve?
Cranial nerve six (CN VI), also known as the abducens nerve, is one of the nerves responsible for the extraocular motor functions of the eye, along with the oculomotor nerve (CN III) and the trochlear nerve (CN IV).
How do you test for cranial nerve 12?
The 12th (hypoglossal) cranial nerve is evaluated by asking the patient to extend the tongue and inspecting it for atrophy, fasciculations, and weakness (deviation is toward the side of a lesion).
Which cranial nerve is responsible for smell?
The olfactory nerve carries impulses for the sense of smell. The optic nerve carries impulses for the sense of sight. The occulomotor nerve is responsible for motor enervation of upper eyelid muscle, extraocular muscle and pupillary muscle.
What does nerve mean?
(Entry 1 of 2) 1 : sinew, tendon strain every nerve. 2 : any of the filamentous bands of nervous tissue that connect parts of the nervous system with the other organs, conduct nerve impulses, and are made up of axons and dendrites together with protective and supportive structures.