Nerves Unit 4 Part 2 Flashcards
What are the three layers of the cranial meninges?
- Dura Mater
- Arachnoid Mater
- Pia Mater
- Dura mater is the outermost tough membrane
- Arachnoid mater is the filamentous layer
- Pia mater is the thin vascular layer attached to the brain surface
What is the subarachnoid space?
Space between Arachnoid and Pia Mater
Contains CSF
It plays a crucial role in cushioning the brain.
What are choroid plexuses?
Capillaries
Blood flows into the ventricles of brain
They are essential for producing cerebrospinal fluid.
What is the function of Arachnoid Villi?
Absorb Cerebrospinal fluid into the blood.
Define Rostral
Toward the forehead.
Define caudal
Toward the cord.
What are the 4 major parts of the brain?
- Cerebrum
- Cerebellum
- Diecephalon
- Brainstem
Cerebum - 83% brain volume
Cerebellum - houses 50% of the neurons
Brain weighs 3-3.5 pounds
What separates the two cerebral hemispheres?
Longitudinal fissure.
What are gyri and sulci?
Gyri are the ridges of the folds
sulci are the grooves.
What is the surface layer of gray matter in the brain called?
Cortex.
What are deeper masses of gray matter in the brain called?
Nuclei or ganglia.
What are bundles of myelinated axons in the brain referred to as?
Tracts.
What constitutes gray matter?
2 Items
Dendrites and cell bodies.
What constitutes white matter?
Myelinated axons (nerve tracts).
What is the primary function of the frontal lobe?
Voluntary motor functions
Planning, mood, smell, and judgement
What is the primary function of the parietal lobe?
Senses
Taste, touch, temp
What is the primary function of the occipital lobe?
Vision
What is the primary function of the temporal lobe?
Hearing and Language
Memory, emotions
What is the role of the thalamus in the diencephalon?
Receives nearly all sensory information on its way to the cerebral cortex and acts as a relay station.
What are the functions of the hypothalamus?
7 Functions
- Hormone secretion
- Autonomic NS control
- Thermoregulation
- Food and water intake
- Sleep and circadian rhythms
- Memory
- Emotional behavior.
What does the Cerebral Aqueduct of the midbrain connect?
Connects 3rd and 4th ventricles.
What is the function of the corpora quadrigemina?
Visual and auditory reflexes.
What does the pons contain?
Contains ascending sensory tracts and descending motor tracts.
Nuclei concerned w/sleep, hearing, balance, taste, eye movements, facial expression and sensation, respiration, swallowing, bladder control, and posture
What is the medulla oblongata responsible for?
- Adjusting heart rate and force
- blood vessel diameter
- controlling breathing rate and depth.
Cardiac Center
Vasomotor Center
Respiratory Center
What is the function of the cerebellum?
- Produces smooth and coordinated movements
- controls balance and equilibrium.
What are the internal chambers within the CNS called?
Ventricles.
- Lateral
- Third
- Cerebral
- Fourth
- Central
What are the functions of cerebrospinal fluid?
- Buoyancy
- Protection
- Chemical stability.
Ventricles lined w/ependymal cells
Contain choroid plexuses that produce CSF
What is the spinal cord considered in relation to the brain?
Information highway between brain and body.
Extends past L1 as medullary cone and cauda equina
What are the three primary functions of the spinal cord?
- Conduction
- Locomotion
- Reflexes.
What is the anatomy of a nerve?
2 Pieces
Bundle of axons
- Dorsal and Ventral roots
- Dorsal root ganglion
Dorsal - input
Ventral - output
What do dorsal roots carry?
Sensory neurons
What is the definition of a reflex?
Rapid, predictable, involuntary response to a stimulus.
What are the two types of reflexes?
- Autonomic reflexes
- Somatic reflexes.
Autonomic - smooth muscle, heart, glands
Somatic - knee jerk, withdrawal
What is a cerebral aneurysm?
A weak spot in an arterial wall that swells and can rupture.
Risk groups - high blood pressure, smokers, genetic, over 40
Symptoms - vision change, eye pain, facial weakness and numbness
What is a stroke?
When blood flow to the brain stops.
Risk groups - history of strokes, high blood pressure, heart disease, smoking
Symptoms - vision loss, confusion, speech problems, motor problems
What are the two types of strokes?
- Hemorrhagic stroke
- Ischemic stroke.
What causes Bell’s Palsy?
Inflammation of the facial nerve (VII).
Risk groups - pregnant women, diabetics, flu
Symptoms - facial asymmetry, sudden paralysis
Where is the Cauda Equinae located?
L2 to S5
Where is Gray and White matter located?
Spinal Cord
Gray - neuronal cell bodies
White - myelinated axons
What are the 2 types of horns of gray matter and what do they contain?
- Dorsal/Posterior - interneurons
- Ventral/Anterior - motor neurons
What are the 3 connective tissues wrappings of a nerve?
- Endoneurium - around axon
- Perineurium - around fascicles
- Epineurium - around nerve
What are the 3 types of Nerves?
- Sensory
- Motor
- Mixed
How many cranial nerves are there?
12
What is a Subdural Hematoma?
Damage to veins below the Dura Mater, where blood collects on the surface of the brain
Risk groups - head injuries, falling, alcoholism
Symptoms - confusion, nausea, loss of vision, seizures
What is Trigeminal Neuralgia?
Tic Douloureux
Pain that affects the trigeminal nerve
Stabbing pain to side of face, associated with burning. Constant pain
What is Parkinson Disease?
Degenerative disorder w/a depletion of dopamine
Loss of substantia nigra (dopamine neurons)
Resting tremors
Bradykinesia - slow movements
Shuffling gait - slow movements
