1. Nervous System Anatomy and Physiology Review Neurological Assessment

2. Anatomy and Physiology

3. Neurons The basic and functional unit Central Nervous System The spinal cord and brain Peripheral Nervous System The nerves and nerve ganglia Autonomic Nervous System Sympathetic and parasympathetic

4. Neurons

5. Types Sensory (Afferent) neurons: transmit impulses to spinal cord or brain Motoneurons(efferent) : transmit impulses away from brain or spinal cord to muscles or glands Interneurons: transmit impulses from sensory neurons to motoneurons

6. Structure Cell Body: contains a nucleus and other cytoplasmic matter Axon: carries impulse away from cell body Dendrites: carry impulses toward cell body Myelin: multiple, dense layers of membrane around an axon or dendrite; myelinated nerve fibers transmit nerve impulses more rapidly than nonmyelinatedfibers Synapse Point of contact between axon of one cell and dendrite of another Neuroglia: support, defend, and nourish

7. Brain

8. Brain Stem Medulla: conducts impulses between the cord and brain Pons: conducts impulses between the cord and various parts of the brain Midbrain Integrates and analyzes sensory input from ears, eyes and various regions of the cerebral cortex Cerebellum: exerts synergic control over skeletal muscles

9. Diencephalon Thalamus: crudely translates sensory impulses into sensations but does not localize them Hypothalamus: makes ADH and oxytocin, which are secreted by the posterior pituitary Optic chiasm: the point of crossing over (decussation) of optic nerve fibers

10. Cerebral Cortex Frontal lobe: influences abstract thinking, sense of humor, and uniqueness of personality Parietal lobe: Interpret sensations; provide appreciation of size, shape, texture, and weight Temporal lobes Translate nerve impulses into sensations of sound and interpret sounds (Wernicke’s area; usually in dominant hemisphere) Occipital lobe Translates nerve impulse into sights and interprets sights

11. Brain and Cord Fluid Spaces Subarachnoid space around the brain and cord, extending into the fourth and fifth lumbar vertebrae Central canal inside the cord Ventricles and cerebral aqueduct inside the brain; four cavities known as first, second, third, fourth ventricles Cerebrospinal fluid (CFS) formed by plasma filtering from network of capillaries (chronoid plexus) in each ventricle CFS circulates throughout ventricles, brain and subarachnoid space and returns to blood via venous sinuses of brain

12. Autonomic Nervous System

13. Two Divisions Sympathetic: adrenergic fibers secrete norepinephrine; influences smooth muscle of blood vessels, hairs, and sweat glands Parasympathetic: cholinergic fibers secrete acetylcholine, influences digestive tract and smooth muscle to promote digestive gland secretion, peristalsis, and defecation; influences the heart to decrease rate and strengthen contractility

14. DIAGNOSTIC PROCEDURES

15. NEUROLOGIC ASSESSMENT Definition: systematic evaluation of the cranial nerves, motor and sensory functioning, and mental status to detect neurologic abnormalities

16. Cranial Nerves

17. Olfactory (I) ability to identify familiar odors such as mini or alcohol with eyes closed and one nostrils occluded at a time

18. Optic (II) visual acuity measured by use of Snellen chart or by gross estimation with reading material; gross comparison of visual fields with those of examiner; color perception

19. Oculomotor (III), Trochlear (IV) and Abducens(VI) ability of the pupils to react equally to light and to accommodate to varying distances

20. Trigeminal (V) sensation of the face evaluated by lightly stroking cotton across forehead, chin, and cheeks while the client’s eyes are closed; ability to clench the teeth (jaw closed)

21. Facial (VII) symmetry of the facial muscles as the client speaks or is asked to make faces

22. Acoustic or Vestibulocochlear (VIII) hearing acuity determined by watch tick or whispered numbers; Weber’s test may be performed by holding the stem of a vibrating tuning fork at midline of the skull (should be heard equally in both ears)

23. Glossopharyngeal (IX) and Vagus (X) uvula should hang in midline; swallow and gag reflexes should be intact

24. Spinal accessory (XI) symmetric ability to turn the head or shrug the shoulders against counterforce of the examiner’s hands

25. Hypoglossal (XII) ability to protrude the tongue without deviation, to left or right, and without tremors

26. Motor function Balance Observation of gait Romberg Test: positive if the client fails to maintain an upright position with feet together when the eyes are closed Coordination: ability to touch the finger to the nose when arms are extended or to perform similar tasks smoothly Muscle strength: evaluated by having the client move symmetrical muscle groups against opposition supplied by the examiner

27. Sensory function : bilateral testing of the response to light touch with cotton, sharp versus dull stimuli, vibration of a tuning fork Mental Status (cerebral functioning) Level of consciousness: determined by the response to stimuli (verbal, tactile or painful) Orientation to person, place, and time: determined by general conversation and direct questioning >Judgment, memory, and ability to perform simple calculations >Appropriateness of behaviour and mood Reflexes Deep tendon reflexes (biceps, triceps, patellar, Achilles) with a reflex hammer; classification from 0 (absent) to 4+ (hyperactive); 2+ is normal Plantar: plantar flexion of the foot when the sole is stroked firmly with a hard object such as tongue blade; abnormal adult response (dorsiflexion of the foot and fanning of the toes) is described as a positive Babinski and is indicative of corticospinal tract disease

28. GLASGOW COMA SCALE (GCS) Definition : technique of objectifying a client’s level of responses; client’s best response in each are is given a numeric value, and the three values are totalled for a score ranging from 3 (deep coma) to 15 (normal) Eye-opening ability: spontaneous (4); to speech (3); to pain (2); no response (1) Motor response: obeys commands (6); localizes pain (5); withdraws (4); abnormal flexing (3); extension (2); no response (1) Verbal response: oriented (5); confused (4); inappropriate words (3); incomprehensible soundes (2); no response (1)

29. COMPUTERIZED TOMOGRAPHY (CT) Definition >Cross-sectional visualization of the head or other body cavity determined by computer analysis of relative tissue density as an x-ray beam passes through >Provides three-dimensional information about location and extent of tumors, infracted areas, atrophy, and vascular lesions >May be done with intravenous injection of dye for contrast enhancement

30. MAGNETIC RESONANCE IMAGING (MRI) Definition >Uses magnetic fields and radio waves to produce cross-sectional images >Produces accurate images of blood vessels, bone marrow, gray and white brain matter, spinal cord, globe of the eye, heart, abdominal structures, and breast tissue, and can monitor blood velocity

31. LUMBAR PUNCTURE Definition: involves the introduction of a needle into the subarachnoid space below the spinal cord, usually between L3 and L4 or L4 and L5 Purposes >Withdrawal of cerebral spinal fluid for diagnostic purposes or to reduce spinal pressure (normal is 70 to 200 mm H2O) >Measurement of spinal pressure (Queckenstedt’s test involves compression of the jugular veins; normally pressure will rise; but it blockage exists, pressure will not change) >Injection of medication such as anesthetics

32. POSITRON EMISSION TOMOGRAPHY (PET) Definition >Client is given strong radioactive tracers that emit signals, computer analysis of the emitted gamma rays forms images >Determines blood flow, glucose metabolism, and oxygen extraction >Effective in diagnosis of brain attack, brain tumors, epilepsy; can evaluate progress of >Alzheimer’s disease, Parkinson’s disease, bipolar disorders, and head injuries

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