CH. 15 NERVES Flashcards
Meninges
(outer to inner most layer)
- Dura mater
- Arachnoid mater
- Pia mater
Dura mater
- outer layer, fibrous layer
Arachnoid mater
-Middle, two layered, fibrous and elastic membrane that covers folds and fissures of brain.
Subarachnoid space
- between arachnoid and Pia mater where CSF circulates
Pia mater
contains small vessels that supply blood to brain. (inner layer)
Falx Cerebri
fold of dura mater that separates the 2 cerebral hemispheres
tentorium cerebri
supports temporal and occipital lobes and separates the cerebral hemispheres from cerebellum
CSF
- colorless, odorless fluid made in choroid plexus
- provides cushion, maintain norma; intracranial pressure, provide nutrition and remove metabolic waste
Cerebrum
largest part of the brain and is composed of 2 hemispheres
Frontal lobe
-Control intellectual function awareness of self, personality and autonomic responses.
- Left lobe: Broca’s Area; formulation of words
- primary motor cortex that are responsible for functions related to voluntary motor activity
EX. right side nerve controls left side body
Parietal lobe
- Primary somesthetic (sensory) cortex
- receives sensory input such as position sense, touch, shape and texture of objects.
EX. cross at medulla where left side nerves control right side body.
right nerves control left side body
Temporal lobe
- primary auditory cortex
- Weirnickes area, located on left temporal lobe, responsible for comprehension of spoken and written language.
- Auditory, visual and somatic sensory input.
Occipital lobe
primary visual cortex
Dicenphalon
Composed of thalamus, hypothalamus, epithalamus and subthalamus
Thalamus
integration station of spinal cord
Hypothalamus
- maintains homeostasis
- regualtion of body temp, hunger, thirst
- formation of ANS responses and storage and secretions of hormones from pit gland.
Epithalamus
pineal gland, sleepiness and helps regulate some endocrine function
Sub thalamus
Part of basal ganglia
Brain stem
- MIDBRAN
- PONS
- MEDULLA OBLONGATA
Midbrain
- relay stimuli concerning muscle movement to other brain structures
- NERVES : III & IV
Pons
-regulates impulses to brain centers & lower spinal nerves
NERVES: V, VI, VII, & VIII
Medulla Oblongata
- contains reflex centers for controlling involuntary functions such as breathing, sneezing, swallowing, coughing, vomiting, and vasoconstriction.
NERVES: IX, X, XI, &XII
Cerebellum
-coordinates movement, equilibrium, muscle tone, & proprioception
CN I
OLFACTORY NERVE (sensory) - smell reception and interpretation
CN II
OPTIC (SENSORY)
- visual acuity and fields
CN III
OCULOMOTOR (motor)
- raise eyelids, most extra ocular movements
- parasympathetic: pupillary constriction, change lens shape.
CN IV
TROCHLEAR (motor)
- downward, inward eye movement
CN V
TRIGERMINAL (sensory & motor)
- Motor: jaw opening & clenching, chewing & mastication
- Sensory: sensation to cornea, iris, lacrimal glands, conjunctiva, eyelids, forehead, nose, mouth and etc…
CN VI
- ABDUCENS (motor)
- Lateral eye movement
CN VII
- FACIAL (Motor & sensory)
- Motor: Facial expression movements
-Sensory: taste on the anterior two thirds of tongue, sensation to pharynx.
Parasympathetic: secretion of saliva and tears
CN VIII
ACOUSTIC (SENSORY)
- hearing and equilibrium
CN IX
GLOSSOPHAYNGEAL (Motor and Sensory)
- Motor: voluntary muscles for swallowing and phonation
- Sensory: sensation of nasopharynx, gag reflex, taste on the posterior one third of tongue
- parasympathetic: secretion of salivary glands
carotid reflex
CN X
VAGUS (motor & sensory)
- Motor: voluntary muscles of phonation (guttural speech sounds) and swallowing
- Sensory: sensation behind ear and part of external ear canal
- parasympathetic: secretion of digestive enzymes: peristalsis, carotid reflex, involuntary heart action, lungs and digestive tract
CN XI
SPINAL ACCESORY (motor) - shoulder shrug
CN XII
HYPOGLOSSAL ( MOTOR)
- tongue movement for speech and swallowing.
Multiple Sclerosis
- progressive demyelination of nerve fibers of the brain and spinal cord.
- ages 20-40, 3 times more common in women
- Symptoms: depression, fatigue, paresthesias, muscle weakness, dipolpia, nystagmus, gait, instability
Meningitis
- inflammation of the meninges
- symptoms: nuchal rigidity ( stiff neck), decrease level of con, confusion.
Encephalitis
- inflammation of the brain tissue in the meninges.
- onset may be gradual or sudden
- symptoms: N/V, irritability, decrease consciousness, motor weakness, tremors, seizures and aphasia.
Spinal cord injury
- injury to cervical spinal cord = quadriplegia or tetraplegia.
- injury to thoracic or or lumbar = paraplegia
- symptoms: paresthesia and anesthesia, spastic paralysis,
Parkinsons disease
- chronic progressive movement disorder resulting from the degeneration of the dopamine- producing neurons in substania nigra of basal ganglia.
- symptoms: tremors in body, bradykinesia, rigidity, postural instability
- shuffle gait, muscle weakness, trunk-forward, and finger pill-rolling tremor
Stroke
- Cerebral blood vessels become occluded by thrombus or embolus or when intracranial hemorrhage occurs, the brain tissue become ishemic.
- Level of consciousness assessment
- dysphagia, aphasia and partial loss of vision
Alzheimers disease
- incurable, de
