NR 304 Chpt 24 Notes

Chapter 24 Notes: The Neurological System *Pay attention to pictures and charts for this test* Structure & Function ➔ Nervous system divided into two parts: ◆ Central nervous system (CNS) , which includes brain and spinal cord ◆ Peripheral nervous system (PNS) , which includes all nerve fibers outside brain and spinal cord ● Includes: ○ 12 pairs of cranial nerves, 31 pairs of spinal nerves, with all of their branches ● Carries sensory (afferent) messages to CNS from sensory receptors ● Motor (efferent) messages from CNS to muscles and glands, as well as autonomic messages that govern internal organs and blood vessels ● DO NOT FOCUS TOO MUCH ON PICTURE BELOW ➔ Cerebral Cortex ◆ Cerebral cortex is the cerebrum's outer layer of nerve cells. ◆ Cerebral cortex is the center of functions governing thought, memory, reasoning, sensation, and voluntary movement. ● Each half of the cerebrum is hemisphere . ● Each hemisphere divided- 4 lobes: frontal, parietal, temporal & occipital ➔ Lobes of Cerebral Cortex ◆ Lobes have areas that mediate specific functions: ● Always ask on where they were hit on their head to find out what places were affected for CT ◆ Frontal lobe concerned with personality, behavior, emotions, intellectual function ● Broca’s area in frontal lobe mediates motor speech ◆ Parietal lobe’s postcentral gyrus is primary center for sensation ◆ Occipital lobe is primary visual receptor center

Chapter 24 Notes: The Neurological System *Pay attention to pictures and charts for this test* ◆ Temporal lobe behind ear, has primary auditory reception center, taste, smell ● Wernicke’s area in temporal lobe associated with language comprehension ➔ Damage of Cerebral Cortex ◆ Damage to specific cortical areas produces a corresponding loss of function: ● Motor weakness ● Paralysis ● Loss of sensation ● Impaired ability to understand and process language ◆ Damage occurs when highly specialized neurologic cells are deprived of blood supply , such as when a cerebral artery becomes occluded. ➔ Cerebral Cortex (picture) ➔ Central Nervous System Components ◆ Basal ganglia ● Gray matter in two cerebral hemispheres that form subcortical associated motor system ( extrapyramidal system ) ◆ Thalamus ● Main relay station where sensory pathways of spinal cord, cerebellum, and brainstem form synapses ◆ Hypothalamus ● Major respiratory center with basic function control and coordination ◆ Cerebellum ● Concerned with motor coordination and muscle tone of voluntary movements

Chapter 24 Notes: The Neurological System *Pay attention to pictures and charts for this test* ➔ Motor Pathways ● What is the function of the cerebellum? ○ Unbalanced gait, should be put on fall precautions ○ Need assisted devices to walk because of deficits ○ They need to get up and walk before deficits worsen ● Corticospinal or pyramidal tract ○ Fibers mediate voluntary movement, particularly very skilled, discrete, purposeful movements. ○ Motor nerve fibers travel to the brainstem crossing to the opposite, contralateral side, (pyramidal decussation) and then pass down in the lateral column of the spinal cord. ● Extrapyramidal tracts ○ Include: ◆ motor nerve fibers originating in the motor cortex, basal ganglia, brainstem, and spinal cord outside the pyramidal tract. ◆ subcortical motor fibers that maintain muscle tone and control body movements, especially gross automatic movements, such as walking. ● Cerebellar system ○ Coordinates movement, maintains equilibrium and posture ○ Receives information on position of muscles and joints, body’s equilibrium, and kind of motor messages sent from cortex to muscles ○ Integrates information using feedback pathway to exert control

Chapter 24 Notes: The Neurological System *Pay attention to pictures and charts for this test* ➔ Upper Motor Neurons ◆ Complex of descending motor fibers can influence or modify lower motor neurons ◆ Located completely within CNS; convey impulses from motor areas of cerebral cortex to lower motor neurons ● Examples of upper motor neuron diseases are cerebrovascular accidents, cerebral palsy, and multiple sclerosis. ➔ Lower Motor Neurons ◆ Final common pathway, providing final contact with muscle ◆ Located in anterior gray column of spinal cord, but nerve fibers extend to muscle ◆ Movement must be translated into action by lower motor neuron fibers. ● Examples of lower motor neurons are cranial nerves and spinal nerves of the peripheral nervous system. ● Examples of lower motor neuron diseases are spinal cord lesions, poliomyelitis, and amyotrophic lateral sclerosis, compression syndrome, bell's palsy, polio ➔ Motor Neurons ➔ Reflexes ● The most important thing: how do you test these reflexes? ○ Look at pictures in the book of visual representation of how reflexes are tested ◆ Reflexes are basic defense mechanisms of nervous system ● Involuntary ; below level of conscious control permitting quick reaction to potentially painful or damaging situations ◆ Three types of reflexes: ● Stretch on/deep tendon ( myotatic ), e.g., knee jerk

Chapter 24 Notes: The Neurological System *Pay attention to pictures and charts for this test* ➔ Spinal Nerves ◆ 31 pairs of spinal nerves arise from the length of the spinal cord and supply the rest of the body. ● Named for region of spine from which they exit: ○ 8 cervical 12 thoracic, 5 lumbar, 5 sacral, 1 coccygeal ● “Mixed” nerves ○ Contain both sensory and motor fibers ○ Each innervates a particular segment of the body ● Dermal segmentation ○ Cutaneous distribution of various spinal nerves ➔ Dermatomes ◆ Dermatome ● It is a certain area of the body that is affected by specific nerves ○ Thumb, fingers ● Circumscribed skin area supplied mainly from one spinal cord segment through particular nerve ● Dermatomes overlap ; if one nerve is severed, most sensations are transmitted by one above and one below. ◆ Useful landmark dermatomes ● Thumb, middle finger, fifth finger are C6, C7, and C8 ○ If someone has trauma to those areas, expect those areas to be affected ● Axilla at T1

Chapter 24 Notes: The Neurological System *Pay attention to pictures and charts for this test* ○ It will only involve the axilla ● Nipple at T4 ● Umbilicus at T10 ○ Where is T10? In the trunk ● Groin in region of L1 ○ L is the lumbar region, expect it to mess with the knees ● Knee at L4 ➔ Autonomic Nervous System ◆ Peripheral nervous system composed of cranial nerves and spinal nerves ◆ Carry fibers divided functionally into two parts: ● Somatic fibers innervate skeletal ( voluntary ) muscles. ● Autonomic fibers innervate smooth ( involuntary ) muscles, cardiac muscle, and glands. ○ It acts unconsciously without you making your body do it ◆ Autonomic systems mediate unconscious activity. ➔ Developmental Competence: Infants ◆ The Neurological system is not completely developed at birth. ○ If a baby is not developing those reflexes, there is a dysfunction and they will be tested. This is why they are tested at certain ages for things that they should be able to do at that age ● Movement is directed primarily by primitive reflexes. ● Persistence of primitive reflexes is an indication of CNS dysfunction. ● Sensory and motor development proceed with gradual acquisition of myelin needed to conduct most impulses. ● As myelination develops, infants are able to localize stimulus more precisely and make more accurate motor responses. ➔ Developmental Competence: Aging Adults ◆ Atrophy with steady loss of neuron structure in brain and spinal cord ● Atrophy is muscle wasting- there will be no control and problems in the brain and spinal cord ○ Mostly common in older people ◆ Velocity of nerve conduction decreases making reaction time slower in some older persons. ● This is why aging adults take longer to perform tasks. They have to process it in their head and perform those motions ◆ Increased delay at synapse results in diminished sensation of touch, pain, taste, and smell. ◆ Motor systems may show general slowing down of movement, muscle strength, and agility decrease. ● If you have been in bed for a few days, when you get up you will have to get used to the gravity and let your equilibrium balance and your blood flow level out. ● The older you are, the more likely you are to have this feeling of being unbalanced; progressive quicker and easier

Chapter 24 Notes: The Neurological System *Pay attention to pictures and charts for this test* ● Dizziness/vertigo : Ask about ○ onset, duration, description, and frequency. ○ associated with change in position. ○ vertigo characteristics—objective or subjective vertigo. ● Seizures : Ask about ○ course and duration. ◆ What did the person that observed you having the seizure say what it looks like? ○ motor activity in the body. ◆ Silent seizures ○ associated clinical presentations. ○ postictal phase. ○ precipitating factors. ○ medication therapy. ○ coping strategies. ● Tremors : Ask about ○ onset, type, duration, and frequency. ○ precipitating and alleviating factors. ● Weakness : Ask about ○ localized or generalized, distal or proximal. ○ impact on mobility or ADLs. ● Incoordination : Ask about ○ problems with balance while standing or ambulating. ○ lateral drifting, stumbling, or falling. ○ legs giving way and/or clumsy movements. ● Numbness or tingling : Ask about ○ onset, duration, and location. ○ whether it occurs with activity. ● Difficulty swallowing : Ask about ○ With solids or liquids ○ Drooling ● Difficulty speaking : Ask about ○ onset, pattern, and duration. ◆ What are you doing when it happens? What triggers it? ○ forming words or saying what you want to say. ● Patient-centered care : Ask about ○ information regarding past pertinent medical history. ● Environmental and occupational hazards : Ask abou t ○ exposure history. ◆ Work- chemicals, asbestos, extreme temperature, altitude ○ medication history: Rx and OTC. ○ alcohol history ◆ How often? How much? When was your last drink? ○ substance abuse/drug history.

Chapter 24 Notes: The Neurological System *Pay attention to pictures and charts for this test* ◆ How often? How much? When did you use it last? ➔ Additional History: Infants and Children ● Ask about ○ maternal and/or fetal problems during pregnancy and delivery. ◆ Assess the mom first, did they have any problems and what was their birth like? ● Infants can be traumatized coming out ○ gestational status, birth weight, and Apgar score. ○ reflexes and motor performance. ○ presence of seizure activity. ◆ High temperatures lately? High temps can cause seizures ○ meeting developmental milestones. ◆ Are they developing through the stages properly? ○ environmental exposure to lead. ○ learning problems identified. ○ significant family history. ○ participation in sports—injury history. ➔ Additional History: Aging Adult ● Give them more time to answer these questions and have their caretaker present to help answer the questions as well ◆ Dizziness : Ask about ● association with positional change or activity or medication. ● impact on ADLs. ● safety modifications. ◆ Memory : Ask about ● decrease in mental function or confusion. ● onset, duration, and frequency. ◆ Tremor : Ask about ● location. ● precipitating and alleviating factors. ● impact on ADLs. ◆ Sudden vision change : Ask about ● onset, duration, and frequency. ● loss of consciousness and safety. ● impact on ADLs. ➔ Objective Data: Preparation ● When collecting data always start with neurological status/mental status and the procedures they have had in the past, cranial nerve functions ◆ Perform screening neurologic examination on well persons with no significant findings from history. ◆ Perform complete neurologic examination on persons with neurologic concerns .

Chapter 24 Notes: The Neurological System *Pay attention to pictures and charts for this test* ● Motor function: ○ Note mobility and facial symmetry as a person responds to selected movements. ○ Have the person puff cheeks, then press puffed cheeks in, to see that air escapes equally from both sides ● Sensory function: (not tested routinely) ○ Test only when you suspect facial nerve injury. ○ When indicated, test sense of taste by applying a cotton applicator covered with solution of sugar, salt, or lemon juice to tongue and ask the person to identify taste. ◆ Cranial nerve VIII: acoustic nerve (vestibulocochlear) ● Test hearing acuity by ability to hear normal conversation and by whispered voice test. ◆ Cranial nerves IX and X: glossopharyngeal and vagus nerves ● Motor function ○ Depress tongue with tongue blade, and note pharyngeal movement as the person says “ahhh” or yawns; uvula and soft palate should rise in midline, and tonsillar pillars should move medially. ○ Touch posterior pharyngeal wall with tongue blade, and note gag reflex; voice should sound smooth, not strained. ● Sensory function ○ Cranial nerve IX does mediate taste on the posterior one third of tongue, but technically too difficult to test. ◆ Cranial nerve XI: spinal accessory nerve ● Examine sternomastoid and trapezius muscles for equal size. ● Check equal strength by asking the person to rotate head against resistance applied to side of chin. ● Ask the person to shrug shoulders against resistance. ◆ Cranial nerve XII: hypoglossal nerve ● Inspect tongue; no wasting or tremors should be present. ● Note forward thrust in midline as the person protrudes tongue. ● Ask the person to say “light, tight, dynamite,” and note that lingual speech (sounds of letters l, t, d, n) is clear and distinct ➔ Inspect and Palpate Motor System: Muscles ◆ Size ● Inspect all muscle groups for size noting bilateral comparison. ◆ Strength ● Test muscle groups of extremities, neck, and trunk. ◆ Tone : normal tension in relaxed muscles ● Persuade the person to relax completely, and move each extremity smoothly through a full range of motion; normally note mild, even resistance to movement. ◆ Involuntary movements

Chapter 24 Notes: The Neurological System *Pay attention to pictures and charts for this test* ● Normally none occur; if present, note location, frequency, rate, and amplitude; note if movements can be controlled at will. ➔ Coordination and Skilled Movements ◆ Rapid alternating movements (RAM) ◆ Ask the person to pat knees with both hands, lift up, turn hands over, and pat knees with backs of hands; then ask the person to do this faster. ◆ Normally done with equal turning and quick rhythmic pace ◆ Alternatively, ask the person to touch thumb to each finger on same hand, starting with the index finger, then reverse direction. ● Finger-to-finger test ● Finger-to-nose test ● Heel-to-shin test ➔ Cerebellar Function Tests ◆ Balance tests ● Gait : observe as the person walks 10 to 20 feet, turns, and returns to starting point ○ Normally the person moves with a sense of freedom; gait is smooth, rhythmic, and effortless; opposing arm swing is coordinated; the person turns smooth; step length about 15 inches from heel to heel. ○ Tandem walking: Ask the person to walk straight line in heel-to- toe fashion ◆ Romberg sign ◆ Ask the person to stand up with feet together and arms at sides; when in stable position, ask the person to close eyes and to hold position for about 20 seconds. ● Normally the person can maintain posture and balance even with visual orienting information blocked. ◆ Ask the person to perform shallow knee bend or hop in place, first on one leg, then other. ◆ Demonstrates normal position sense, muscle strength, and cerebellar function ● Some individuals cannot hop because of aging or obesity. ➔ Assess Sensory System ◆ Ask the person to identify various sensory stimuli in order to test intactness of peripheral nerve fibers, sensory tracts, and higher cortical discrimination. ◆ Routine screening procedures include testing superficial pain, light touch, and vibration in few distal locations, and testing stereognosis. ◆ Complete testing of sensory system warranted in those with neurologic symptoms (e.g., localized pain, numbness, and tingling) or if you discover abnormalities. ◆ Compare sensations on symmetric parts of body. ● When you find definite decrease in sensation, map it by systematic testing in that area.

Chapter 24 Notes: The Neurological System *Pay attention to pictures and charts for this test* ○ Measurement of stretch reflexes reveals intactness of reflex arc at specific spinal levels and normal override on reflex of higher cortical levels. ○ Limb should be relaxed and muscle partially stretched. ○ Stimulate reflex by directing short, snappy blow of reflex hammer onto muscle’s insertion tendon. ● Bilateral comparison : ○ responses should be equal ● DTRs 4-Point Scale ○ Reflex response graded on 4-point scale ○ 4 = very brisk, hyperactive with clonus, indicative of disease ○ 3 = brisker than average, may indicate disease ○ 2 = Average, normal ○ 1 = diminished, low normal, or occurs with reinforcement ○ 0 = no response ○ Subjective scale requires clinical practice; scale not completely reliable; a wide range of normal exists in reflex responses. ● Reinforcement ○ Alternate technique to help elicit reflexes by performing an isometric exercise in a different muscle group. ○ Must document that this technique was used. ➔ Testing Reflexes ◆ Biceps reflex, C5 to C6 ● Support the person’s forearm on yours; place your thumb on biceps tendon and strike a blow on your thumb. ● Normal response is contraction of biceps muscle and flexion of forearm. ◆ Triceps reflex, C7 to C8 ● Tell the person to let arm “just go dead” as you strike triceps tendon directly just above the elbow. ● Normal response is extension of forearm. ◆ Brachioradialis reflex, C5 to C6 ● Hold the person’s thumbs to suspend forearms in relaxation and strike forearm directly, about 2 to 3 cm above radial styloid process. ● Normal response is flexion and supination of forearm. ◆ Quadriceps reflex, L2 to L4 (knee jerk) ● Let lower legs dangle freely to flex knee and stretch tendons; strike tendon directly just below patella. ● Normal response is extension of lower leg. ◆ Achilles reflex, L5 to S2 (ankle jerk) ● Position the person with knee flexed; hold foot in dorsiflexion and strike Achilles tendon directly. ● Normal response is foot plantar flexes against your hand.

Chapter 24 Notes: The Neurological System *Pay attention to pictures and charts for this test* ➔ Clonus ◆ Clonus: test when reflexes hyperactive ◆ Support lower leg in one hand and with other hand, move foot up and down to relax muscle; then stretch muscle by briskly dorsiflexing foot; hold the stretch. ◆ Normal response: you feel no further movement ● When clonus present , you will note rapid rhythmic contractions of calf muscle and movement of foot. ◆ Sustained clonus is associated with UMN disease. ➔ Superficial Reflexes ◆ Superficial (cutaneous) reflexes ● Sensory receptors in skin rather than in muscles; motor response is localized muscle contraction. ● Abdominal reflexes: upper: T8 to T10; lower: T10 to T12 ● Person in supine position, knees slightly bent; use handle end of reflex hammer to stroke skin ● Move from each corner toward the midline at both upper and lower abdominal levels. ● Normal response is ipsilateral contraction of abdominal muscle with observed deviation of umbilicus toward stroke. ◆ Cremasteric reflex, L1 to L2 (not routinely done) ● On male, lightly stroke inner aspect of thigh with reflex hammer or tongue blade. ● Note elevation of ipsilateral testicle. ◆ Plantar reflex, L4 to S2 ● Position thigh with slight external rotation. ● With reflex hammer, draw a light stroke up lateral side of sole of foot and inward across ball of foot, like an upside-down “J.” ● Normal response is plantar flexion of toes and inversion and flexion of forefoot. ➔ Neurological Recheck ● Abbreviation of neurological exam for head trauma or neurological deficit caused by systemic disease ◆ Level of consciousness — ● change in LOC—perform relative assessments ◆ Motor function — ● check voluntary movement of each extremity by giving specific commands ◆ Pupillary response — ● check for PERLA noting size in millimeters ◆ Vital signs — ● measure and monitor ◆ Glasgow coma scale — ● eye opening, motor and verbal response—quantitative measurement tool to assess LOC

Chapter 24 Notes: The Neurological System *Pay attention to pictures and charts for this test* ◆ Stepping reflex: ● hold infant on flat surface—note regular alternating steps ● Reflex disappears before voluntary walking. ➔ Developmental Competence: Preschool and School-Age Children ◆ Assess the child’s general behavior during play activities, reaction to parent, and cooperation with parent and with you. ◆ Much of motor assessment can be derived from watching child undress and dress and manipulate buttons; indicates muscle strength, symmetry, joint range of motion, and fine motor skills. ◆ Use Denver II to screen gross and fine motor skills appropriate for child’s age. ● Note child’s gait both walking and running; allow for normal wide-based gate of toddler and normal knock-kneed walk of preschooler. ◆ Observe child as rising from supine position to sitting position, then to a stand; note muscles of neck, arms, legs, and abdomen. ● Normally child curls up midline to sit up, then pushes off with both hands against floor to stand. ◆ Assess fine coordination using finger-to-nose test. ● Demonstrate procedure first , then ask child to do test with the eyes open, then with eyes closed. ◆ Fine coordination not fully developed until child is 4 to 6 years; consider it normal if younger child can bring finger to within 2 to 5 cm of nose. ● Testing sensation very unreliable in toddlers and preschoolers ◆ May test light touch by asking child to close eyes and point to spot where you touch ◆ When you need to test DTRs in young child, use your finger to percuss tendon. ◆ Use reflex hammer only with an older child; ● coax child to relax, or distract and percuss discreetly when child not paying attention. ◆ Knee jerk present at birth; then ankle jerk and brachial reflex appear; and triceps reflex present by 6 months ➔ Developmental Competence: Aging Adult ◆ Use same examination as with younger adults. ● Cranial nerves mediating taste and smell not usually tested, may show some decline in function ◆ Decrease in muscle bulk most apparent in hand ● Dorsal hand muscles often look wasted, even with no apparent arthropathy. ● Grip strength remains relatively good. ◆ Senile tremors occasionally occur. ◆ Benign tremors include an intention tremor of hands, head nodding, and tongue protrusion. ◆ Dyskinesias : ● repetitive stereotyped movements in jaw, lips, or tongue may accompany senile tremors; no associated rigidity present

Chapter 24 Notes: The Neurological System *Pay attention to pictures and charts for this test* ● Gait may be slower and more deliberate than in a younger person; may deviate from midline path. ◆ RAMs Rapid alternating movements may be difficult to perform ● Loss of sensation and increased stimulus needed to elicit a response. ◆ After 65 years of age, loss of sensation of vibration at ankle malleolus common ; loss of ankle jerk; tactile sensation may be impaired; may need stronger stimuli for light touch; and especially for pain. ◆ DTRs less brisk ; ● those in upper extremities usually present ● ankle jerk commonly lost; ● knee jerks may be lost; because aging people find it difficult to relax limbs ● always use reinforcement when eliciting DTRs ◆ Plantar reflex may be absent or difficult to interpret; ● often, you will not see a definite normal flexor response; still should consider definite extensor response abnormal. ◆ Superficial abdominal reflexes may be absent, probably because of stretching of musculature through pregnancy or obesity. ➔ Health Promotion and Teaching ◆ F.A.S.T. plan—American Heart Association ● F = Face drooping ● A = Arm weakness ● S = Speech difficulty ● T = Time to call 9-1-1 ◆ Review of risk factors: ● HTN ● Cigarette smoking ● Heart disorders ● Vaccination to reduce risk for Herpes Zoster (shingles) in older adult ● Warning Signs of Alzheimer Disease ● Memory loss ● Losing track ● Forgetting words ● Getting lost ● Poor judgment ● Abstract failing ● Losing things ● Mood swings ● Personality change ● Growing passive ➔ Abnormalities in Cranial Nerves ◆ CN I, olfactory nerve ● Anosmia ◆ CN II, optic nerve ● Defect or absent central vision