Cranial nerve, sixth: The sixth cranial nerve is the abducens nerve. It is a small motor nerve that has one task: to supply a muscle called the lateral rectus muscle that moves the eye outward.
Paralysis of the abducens nerve causes inward turning of the eye (internal strabismus) leading to double vision.
The cranial nerves, the abducens nerve included, emerge from or enter the skull (the cranium), as opposed to the spinal nerves which emerge from the vertebral column. There are twelve cranial nerves.
The word “abducens” comes from the Latin “ab-“, away from + “ducere”, to draw = to draw away. The abducens (or abducens) operates the lateral rectus muscle that draws the eye toward the side of the head. The abducens nerve is also called the abducens nerve.
- Cranial nerve, third
Cranial nerve, third: The third cranial nerve is the oculomotor nerve. The cranial nerves emerge from or enter the skull (the cranium), as opposed to the spinal nerves which emerge from the vertebral column. There are twelve cranial nerves. The oculomotor nerve is responsible for the nerve supply to muscles about the eye: The upper […]
- Cranial nerves
Cranial nerves: The nerves of the brain, which emerge from or enter the skull (the cranium), as opposed to the spinal nerves, which emerge from the vertebral column. There are 12 cranial nerves, each of which is accorded a Roman numeral and a name: Cranial nerve I: the olfactory nerve Cranial nerve II: the optic […]
Cranio-: Referring to the cranium, the top portion of the skull, the bony vault that protects the brain. As in craniocleidodysostosis, craniology, craniopharyngioma, craniotomy, etc.
Craniocleidodysostosis: A genetic (inherited) disorder of bone development characterized by: Typical cranial and facial abnormalities with square skull, late closure of the sutures of the skull, late closure of the fontanels (the soft spots), low nasal bridge, delayed eruption of the teeth, abnormal permanent teeth, etc. Absent or incompletely formed collar bones (the “cleido-” part […]
Craniology: The study of variations in size, shape, and proportion of the skull (cranium). Also known as phrenology, it was a pseudoscience of the 18th and 19th centuries based on the belief that a person’s character could be learned by looking with care at the shape of their head and noting each and every bump […]