Cranial Nerves Flashcards
\_\_ pairs of spinal nerves. \_\_ Cervical \_\_ thoracic \_\_ lumbar \_\_ sacral \_\_ coccygeal
31 pairs 8 cervical 12 thoracic 5 lumbar 5 sacral 1 coccygeal
Which cranial nerves have CNS characteristics?
Which have PNS characteristics?
CNS- CN I and CN II (has meninges coverings) Strictly sensory. Soma of those neurons are in the CNS.
PNS- CN III to CN XII
Where do CN I and Cn II originate
In the prosencephalon (forebrain, contains diencephalon and telencephalon)
Where do CN 3-12 originate?
Originate in the mesencephalon (midbrain) and the rhombencephalon (hindbrain, contains metencephalon- pons and cerebellum)
Mnemonics for name and function
Name- On occasion our trusty truck acts funny. Very good vehicle any how.
Function- Some say money matters, but my brother says big brains matter more.
Mesencephalon
Midbrain
Rhombencephlon
Hindbrain. Contains metencephalon (pons and cerebellum) and the myelencephalon (medulla)
Metencephalon
Pons and cerebellum. Within the rhombencephalon (hindbrain)
Myelencephalon contains
Medulla. Within the rhombencephalon (hindbrain)
Typically, nerves that emerge from the medial brainstem are __
Typically, nerves that emerge from the lateral brainstem are __
Typically, nerves that emerge between them are ___
medial- Motor, efferent, outbound (exiting CNS)
lateral-Sensory, afferent, inbound (arriving at CNS)
middle- Mixed
2 categories of somatic afferent components
- General (GSA)
-Typical touch/pain sensations (true somatic afferent)
-Fibers convey impulses from the skin and skeletal muscle spindles.
-CN V1, V2, V3, VII, IX, X
2 .Special (SA)
-Involved with CN II and VIII (hearing and balance)
General somatic efferent (GSE)
Somatomotor function (true somatic efferent)
-Skeletal muscles whose origins are not derived from the branchial/pharyngeal arches. This includes extra ocular muscles, tongue muscle.
CNIII, IV, VI, and XII
2 Categories of visceral efferent
- General (GVE)- Innervate smooth muscles, cardiac muscles. Spinal nerves can carry GVE fibers. CN 7, 9, and 10
- Special (SVE)- Goofy one. Not autonomic. Innervate skeletal muscles deep in the neck and face. (deep muscles are usually smooth). Branch of CN V, 7, 9, 10th and part of the 11th (called the cranial root)
2 Categories of the visceral afferent
- General (GVA)- Fibers convey impulses from the sensory receptors in the viscera and blood vessel walls (true autonomic efferent)
CN 9 and 10. - Special (SVA)- Olfactory and gustatory (taste) senses. Cn 1, 7, 9, and 10.
What cranial nerves are located in the telencephalon (within the proencephalon)
CN I (olfactory)
What cranial nerves are located in the Diencephalon (within the proencephalon)
CN II (optic)
Proencephalon
Contains the diencephalon and the telencephalon
What cranial nerves are located in the mesencephalon
CN III (oculomotor) and CN IV (trochlear)
What cranial nerves are located in the metencephalon (pons)?
***Division of the rhombencephalon (hindbrain)
CN V (trigeminal) CN VI (Abducens) CN VII (facial)
What cranial nerves are located in the myelencephalon (medulla) ?
***Division of the rhombencephalon (hindbrain)
CN VIII (Vestibulocochlear) CN IX (Glossopharyngeal) CN X (Vagus) CN XI (Accessory spinal) CN XII (Hypoglossal)
CN I
olfactory
sensory
Olfactory cranial nerve
CN I
sensory
CN II
Optic nerve
Sensory
CN III
Oculomotor nerve
motor
Oculomotor nerve
CN III
motor
CN IV
Trochlear nerve
motor
Trochlear nerve is CN #
IV
motor
CN V
Trigeminal
both
CN VI
Abducens
motor