CN III, II, XI, and XII Flashcards
Describe the pathway of the second order neurons running in the olfactory tract.
The cells: Mitral and Tuft cells.
Bifricate into medial and lateral olfactory striae terminating in the primary olfactry cortex and amygala.
**Does not project to the thalamus.
Where does the primary olfactory cortex send information to following scent?
Primary olfactory cortex goes to: Hypothalamus - Endocrine/autonomic functions. Lmbic system - Amygdala Olfactory association complex Memory system
Describe the pathway for the optic tracts formed after the optic nerves convere at the optic chiasm.
Most of the optic tracts will travel to the Lateral geniculate nucleus of the thalamus.
Some will head to the superior colliculus for sight reflexes and some will head to the pretectal area allowing for the pupillary response.
Describe the pathway that the third order optic neurons take.
Leave the LGN in the thalamus and head to the primary visual cortex in the occipital love via the geniculocalcarine tract (optic radiation)
Which two arteries supply blood to the primary visual cortex?
Mostly supplied by the posterior cerebellar.
The middle cerebellar provides macular collateral supplies.
The acessory cranial nerve provides sensation to what structures?
Trapezius, SCM
and via the abberant vagus provides laryngeal innervation.
Where do the tracts of the accessory nerve originate and terminat?
Arise from dorsal and ventral roots of C1-C6 -> foramen magnum -> join abberant vagal -> Jugular foramen - > posterior cervical triangle to innervate SCM and trapezius.
Where can the ganglia of the hypoglossal CN be found?
Found within the hypoglossal nucleus in the medulla.
Where do the fibers for CN XII arise on the brainstem?
Between Olive and pyramids!
How will a lesion to the hypoglossal cranial nerve present?
Ipsilateral hemiparalysis with the tongue deviating to the side of the lesion!
