Cranial nerve I

Cranial Nerve I

The olfactory nerve, also known as cranial nerve I, is responsible for the sense of smell.

The Cranial Nerve I, also known as the Olfactory Nerve, is the first of twelve paired cranial nerves. It is instrumental in the sense of smell. Unlike most of the cranial nerves, which are mixed nerves, the olfactory nerve is purely sensory.

Anatomy

The olfactory nerve is the shortest of the twelve cranial nerves and only one of two cranial nerves (the other being the optic nerve) that do not join with the brainstem. It passes from its receptors in the nasal mucosa to the olfactory bulb which is part of the forebrain.

Diagram of the olfactory nerve.

Function

The olfactory nerve is responsible for transmitting sensory information related to smell from the nasal cavity to the brain. This is achieved through specialized sensory neurons known as olfactory receptor neurons.

Clinical significance

Damage to the olfactory nerve can result in an impaired sense of smell, a condition known as anosmia. This can be caused by head trauma, infections, and certain neurological disorders such as Parkinson's disease and Alzheimer's disease.

See also

• Cranial nerves
• Olfactory system
• Anosmia