Lecture 5: Brainstem + Cranial Nerves V, VII, IX, X, XI, XII

There are 2 types of efferents (alpha motorneurons or similar) what are they?

1. General Somatic (brachial) efferent=SE (to skeletal muscle)

2. General Visceral efferent (VE) to organ/gland

*Afferents are the same (+ 2 special)

Are spinal nerves all mixed (motor, sensory, visceral)?

Yes

Which cranial nerves are mixed?

CN V

CN VII

CN IX

CN X

Which cranial nerves are pure efferent?

CN III (somatic + visceral)

CN IV (somatic)

CN VI (somatic)

CN XI (somatic)

CN XII (somatic)

Which cranial nerves are pure afferent (all special)?

CN I (olfactory)

CN II (optic)

VIII (vestibulocochlear)

CN I?

Olfactory

CN II?

Optic

CN III?

Oculomotor

CN IV?

Trochlear

CN V?

Trigeminal

CN VI?

Abducens

CN VII?

Facial

CN VIII?

Vestibulocochlear

CN IX?

Glossopharyngeal

CN X?

Vagus

CN XI?

Accessory

CN XII?

Hypoglossal

Cranial Nerve V (Trigeminal) - Which cranial nerves are mostly facial/head sensation (cutaneous, nociception, proprioception). Includes oral cavity sensation?

Ex. Smiling too long, ice cube on face

Sensory Afferent (SA)

Cranial Nerve V (Trigeminal) - Which cranial nerves include jaw muscles (muscles of mastication, mandibular branch)?

Sensory Efferent (SE)

The trigeminal nerve pierces through what region?

What are the 3 roots/divisions?

Pierces through lateral pons

3 roots/divisions: ophthalmic, maxillary, mandibular (O.M.M)

All afferents have first order cell bodies in which ganglion?

Trigeminal ganglion (aka semilunar ganglion)

SA for all afferents (excluding jaw proprioception):

1. First order cell bodies synapse onto which sensory nucleus (except pain/temperature)

2. Second order decussate in pons and travel via what to relay sensory info to the brain?

3. Second order terminates onto what in the thalamus

1. First order synapse onto main trigeminal sensory nucleus (pons)

2. Second order travel via medial lemniscus

3. Second order terminates onto VPM (ventral posterior medial)

SA for nociceptive, thermoceptive, pruriceptive

1. First order neurons have cell bodies where?

2. Axons of the first order cell synapse onto which nucleus?

3. Second order neurons cross and descend down which tract?

4. Second order neurons terminate where in the thalamus + two other thalamic areas

1. First order neurons have cell bodies in trigeminal ganglion

2. First order cells synapse at spinal trigeminal nucleus

3. Second order neurons descend down trigemothalamic tract

4. Second order neurons terminate in VPM (ventral posterior medial) in thalamus