Olfactory tract root (CN I)

Radix tractus olfactorii (striae olfactoriae)

NervousOrgansHead

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What it is
Where the olfactory tract, running back from the olfactory bulb under the frontal lobe, joins the brain at the olfactory trigone and splits into lateral and medial olfactory striae at the anterior perforated substance. Shown as a short stub on both sides; the nerve continues in the peripheral nervous system.
Function
Carries smell to the olfactory cortex (uncus, amygdala) without a thalamic relay.
Size
Stub about 1 cm; root 2.2 mm thick
Clinical note
Frontal meningiomas of the olfactory groove often present with a lost sense of smell on one side.

Nearby nervous structures Amygdala, Arachnoid mater, Dura mater (cranial), Hypothalamus, Oculomotor nerve (CN III), Oculomotor nerve root (CN III), Optic chiasm, Optic nerve (CN II), intracranial part, Optic tract root (CN II), Trochlear nerve (CN IV)