Neuroanatomy - Cranial and Spinal Nerves, Sensory receptors Flashcards
Which nerve does NOT serve only the head & neck structures?
Vagus nerve (X)
Abbreviation for the 12 cranial nerves. States the 12 nerves in order.
“On occasion, our trusty truck acts funny – very good vehicle anyhow”
Sensory, motor, or both? List the order.
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The first cranial nerve extends from the nasal mucosa to olfactory bulb. From there, neurons extend as olfactory tract to primary frontal cortex. S, M or B?
Olfactory nerves (I)
- Sensory fibers for smell
List how the optic nerves reach the occipital cortex. S, M or B?
Optic nerve (II) begins as fibers from retina, then form optic nerves and passes through optic foramen to converge to optic chiasma. Then as optic tract to thalamus, changing to optical radiation to occipital cortex.
- Sensory fibers of vision
What are the 4/6 extrinsic muscles of the eye that the oculomotor nerves control? S, M or B?
- Superior rectus muscle
- Medial rectus muscle
- Inferior oblique muscle
- Inferior rectus muscle
Motor fibers from ventral midbrain (but also parasympathetic fibers to lens and some sensory proprioceptive afferents).
Which cranial nerve innervates the superior oblique eye muscle? S, M or B?
Trochlear nerves - pulley (IV)
- Motor fibers from dorsal midbrain
Which cranial nerves have 3 division and is the largest? What are the 3 divisions? S, M or B?
Trigeminal nerves (V)
Division are: Ophthalmic, maxillary, & mandibular division.
Has both sensory fibers for face, and motor fibers for chewing.
What is the cranial nerve that extends from the pons an is VI? S, M or B?
Abducens nerves (VI) that controls extrinsic eye muscles to abduct eye to control the lateral recuts muscle.
- Motor fibers (but some proprioceptive info)
What is the cranial nerve that extends from the pons/medulla border an is VIII? S, M or B?
Vestibulocochlear nerves (VIII)
- Sensory nerve for balance & hearing
What are the 5 major branches of the facial nerve (VII)?
(The Zebra Bit My Cantaloup)
- Temporal, zygomatic, buccal, mandibular, cervical branch
How is the facial nerves a mixed nerve even though it is primarily motor?
- It is also parasympathetic to lacrimal glands and the 2 pairs salivary glands.
- Sensory from anterior 2/3 of tongue for taste.
Glossopharyngeal nerves (IX) are mixed nerves to & from the medulla. List the motor functions.
- Swallowing & gag reflex
- Parasympathetic fibers to parotid glands that releases saliva
Glossopharyngeal nerves (IX) are mixed nerves to & from the medulla. List the sensory functions.
- Taste, touch, pressure, pain from pharynx & posterior tongue
- Carotid sinus (chemo & baroreceptors)
Which nerve is mixed: parasympathetic motor to heart, lungs, abdominal viscera, and somatic to pharynx & larynx
But also sensory from carotid sinus with proprioceptive info?
Vagus nerve (X)
Accessory nerves (XI) is only ______ rootlets
Spinal (rootlets)
Accessory nerves (XI) supports the vagus nerve and is mostly motor functions. Explain.
Mostly motor to pharynx, larynx, soft palate, and supplies motor fibers to trapezium & sternocleidomastoid muscles
What is the XII cranial nerve and what is it for?
Hypoglossal nerves (XII)
- Motor for tongue to mix food , swallow, and speech
What do we call a network of connecting nerves just outside the spinal cord for all ventral rami branch? Where is it not found?
Nerve plexuses
- Not found for T2-T12
What happens to a damage to one spinal segment or root?
Cannot completely paralyze any limb muscles because each receives nerve supply from more than one spinal nerve (because of nerve plexuses).
What are most branches of the cervical plexus called? C1-C4
Cutaneous nerves
What is the important nerve from the cervical plexus for both motor & sensory fibers to diaphragm?
Phrenic nerve
Which nerve of the brachial plexus is connected to the shoulder, especially the deltoid muscle?
Axillary nerve
Which nerve of the brachial plexus is responsible to flex the arm? What is it connected to?
The musculocutaneous nerve connects to biceps brachii & brachialis.
What does the median nerve of the brachial plexus do?
Flexor muscles in anterior forearm & palm.
Also pronates forearm and flex fingers.
Which nerve of the brachial plexus is associated with the ‘funny bone’? What does it do?
Ulnar nerve, wrist & fingers flexion, adduction and abduction of medial fingers
Which nerve of the brachial plexus allows for elbow extension, supination of forearm, extension of wrist & fingers, and abduction of thumb?
Radial nerve
What is the ventral rami of T1-T12? Which nerves does it have?
Anterolateral thorax (no plexuses)
- Intercostal nerves
Which nerve of the lumbar plexus L1-L4 is responsible for adducting muscles
Obturator nerve, located in medial thigh
What does the femoral nerve of the lumbar plexus do and where is it located?
Femoral nerve is a thigh flexor & knee extensor because it is located at the anterior thigh muscles.
Which nerve of the sacral plexus L4-S4 makes up the tibial and common fibular nerves?
Sciatic nerve at the posterior thigh
What are the two nerves of the sacral plexus that branches to the buttocks?
Superior and inferior gluteal nerves
Which nerve is responsible to erection, voluntary urination, and is located at the layer between sex organs - perineum?
Pudendal nerve
What is the map of the body that allows doctors and surgeons to local the nerve or injury?
Dermatome
Associate the wrappings of nerves.
- Endoneurium: encloses nerve fiber (myelin or neurilemma sheath)
- Perineurium: around group of fibers (fascicle)
- Epineurium: around fascicle to make nerve
how can the sensory receptors be classified as?
- Types of stimuli
- Location
- Structural complexity
Lists the different types of sensory receptors according to stimulus detected.
- Mechanoreceptors
- Thermoreceptors
- Photoreceptors
- Chemoreceptors
- Nociceptors (overstimulation)
Lists the different types of sensory receptors according to location.
- Exteroceptors (outside + special senses)
- Interoceptors (aka visceroceptors - within)
- Proprioceptors (skeletal muscles, tendons, ligaments - monitor, know body parts without looking)
Explain an example of a situation where interceptors are used.
Often associated with discomfort in the body, such as the contractile movement along the stomach, a full bladder, hunger or thirst.
Where are the simple receptors, nonencapsulated nerve endings found?
In epithelia and CT, especially pain, temp, ad pressure.
In nonencapsulated nerve endings, which receptor is an ion channel opens by heat, low pH, and chemicals such as capsaicin?
Vanilloid receptor
In nonencapsulated nerve endings, inflammatory chemicals like histamine is connected to which receptor?
Itch receptor
Which nonencapsulated nerve endings is a light pressure receptors located at the junction of epidermis & dermis? Give an example.
Epithelial tactile complexes
Ex. Merkel discs, responding to light touch
Explain what are hair follicle receptors
A type of nonencapsulated nerve endings that detect bending of hairs - light
List the 6 encapsulated nerve endings.
(The Lake Brings Me Tons of Joy)
- Tactile corpuscle (Meissner’s)
- Lamellar corpuscle (Pacinian)
- Bulbous corpuscle (Ruffini)
- Muscle spindles
- Tendon organs
- Joint kinesthetic receptors
Which encapsulated nerve endings is surrounded by Schwann cells and thin CT, found in der mal papillae and ears that lack hair follicles to serve as discriminative touch?
Tactile corpuscle
Which encapsulated nerve endings has a capsule of multiples layers of collagen fibers that respond to pressure when first applied like vibration?
Lamellar corpuscle
Which encapsulated nerve endings is enclosed by a flattened capsule for deep & continuous pressure?
Bulbous corpuscle
Which encapsulated nerve endings is associated with perimysium and detect muscle stretch, causing a reflex to resist it?
Muscle spindles
Which encapsulated nerve endings is a small bundle of collagen fibers that activates when a muscle shortens, causing a reflex to cause muscle to relax?
Tendon organs
Which encapsulated nerve endings is associated with articular capsules, a combo of lamellar, bulbous and free nerve endings, in which they monitor joint position?
Joint kinesthetic receptors
