J Chapter 23: Neurologic System

J Chapter 23: Neurologic System

1. Name the two parts of the nervous system

   • Central Nervous System (CNS): composed of brain, spinal cord, meninges, and cerebrospinal fluid
   • Peripheral Nervous System (PNS): composed of the nerve fibers that branch off from the spinal cord and extend to all parts of the body, including the neck and arms, torso, legs, skeletal muscles and internal organs
     • autonomic & somatic

2. Describe the various functions of the central nervous system.

   • Interprets sensory info, initiates motor responses, center for thoughts & emotions

3. Describe the function of the peripheral nervous system.

   • carry information from the sensory organs and internal organs to the CNS, and to convey information between the CNS and all other parts of the body outside the brain and spinal cord

4. Relate the name and function of each of the 12 cranial nerves.

   • cranial nerve I: olfactory; sensory; smell cranial nerve II: optic; sensory; vision cranial nerve III: occulomotor; motor- most EOM movement, opening of the eyelids, parasympathetic- pupil constriction, lens shape cranial nerve IV: trochlear; motor; down and inward movement of the eye cranial nerve V: trigeminal; both motor- muscles of mastication sensory- sensation of face and scalp, cornea, mucous membranes of the mouth and nose cranial nerve VI: Abducens; motor; lateral movement of the eye
   • cranial nerve VII: facial; both motor- facial muscles, close eye, labial speech, close mouth sensory- taste(sweet, salty, sour bitter) on anterior two thirds of tongue parasympathetic- saliva and tear secretions cranial nerve VIII: Vestibular; sensory; hearing and equilibrium cranial nerve IX: Glossopharanygeal; both; motor- pharynx(phonation and swallowing) sensory- taste on posterior one third of tongue, pharynx (gag reflex) parasympathetic- parotid gland, carotid reflex cranial nerve X: Vagus; both- motor- pharynx and larynx (talking and swallowing) sensory- general sensation from carotid body, carotid sinus, pharynx, viscera parasympathetic- carotid reflex cranial nerve XI: Spinal or accessory; motor; movement of the trapezius and sternomastoid muscle cranial nerve XII: Hypoglossal; motor; movement of the tongue

5. Relate the term dermatome to the spinal nerves.

   • Dermatome: a circumscribed skin area that supplied mainly from one spinal cord segment through a particular spinal nerve
   • Dermatome of the Thumb, middle finger, and 5th fingers: C6, C7, C8 Dermatome of axilla: level of T1 Dermatome of the nipple: level of T4 Dermatome of the umbilicus: level of T10 Dermatome of the groin: region of L1 Dermatome of the Knee: level of L4

6. Describe the term reflex arc.

   • the nerve pathway involved in an involuntary quick rxn to potentially painful or damaging situations
   • 4 types: (1) deep tendon reflexes, (2) superficial, (3) visceral, (4) pathologic

7. Describe the autonomic nervous system.

   • Composed of spinal and cranial nerves that govern the smooth (or involuntary) muscles, cardiac muscle, and glands + mediates unconscious activity & maintain homeostasis of the body

8. List developmental considerations for infants and older adults.

   • Infants: at birth the system is not developed, motor activity is controlled by the spinal cord and medulla. Very little cortical control exists and neurons are not myelinated. Movement is directed by primitive reflexes. Cerebral cortices develops in the 1st yr which then make reflexes disappear. As myelination occur the cephalocaudal and proximodistal order (head, neck, trunk, extremities) order in which infants gain motor control. At birth sensation is also rudimentary and they need strong stimulus, becomes better at myelination also occurs.
   • Older Adults: aging process causes general atrophy w/ steady loss of neuron structure in the brain and spinal cord, which cause dec in weight and volume w/ a thinning of the cerebral cortex. Velocity of nerve conduction dec between 5-10% making reaction time slower resulting in touch and pain sensations, taste and smell. Motor system slows resulting in slow movement: muscle strength and agility dec. dec in cerebral blood flow and 02 consumption which causes dizziness and loss of balance

9. Differentiate among the three types of neurologic examinations.

   • (1) Gait/ tandem walking (2) Rombers test: standing normally with eyes closed, tests for ability to maintain balance. A positive Romberg sign is a loss of balance with eyes closed. occurs with cerebellar ataxia (MS, alcohol intoxication), loss of proprioception, and vestibular function (3) Rapid alternating movements

10. Incorporate health promotion concepts when performing an assessment of the neurologic system

    • review the s/sx & risk factors of stroke, & discuss ways to change any modifiable risk factors + encourage the patient to seek medical attention for a possible mini stroke