Study Guide Exam #3
Intracranial Regulation
Exemplars- Seizure Disorder, Stroke, Traumatic Brain Injury/Organ Donation/Brain Death,
... [Show More] Post-Concussion
Syndrome, Brain Tumor, Meningitis, Hydrocephalus, Parkinson’s Disease
1. Compare the function and behavior of the neurological system. (Med-Surg, p 1909)
The nervous system consists of two major parts: the central nervous system (CNS), including the brain and
spinal cord, and the peripheral nervous system, which includes the cranial nerves, spinal nerves, and autonomic
nervous system. The function of the nervous system is to control motor, sensory, autonomic, cognitive, and
behavioral activities. The brain itself contains more than 100 billion cells that link the motor and sensory
pathways, monitor the body’s processes, respond to the internal and external environment, maintain
homeostasis, and direct all psychological, biologic, and physical activity through complex chemical and
electrical messages.
2. Describe the structures and functions of the central and peripheral nervous systems. (Med-Surg, p 1910)
CENTRAL NERVOUS SYSTEM
The brain is divided into three major areas: the cerebrum, the brain stem, and the cerebellum. The cerebrum is
composed of two hemispheres, the thalamus, the hypothalamus, and the basal ganglia. The brain stem includes
the midbrain, pons, and medulla. The cerebellum is located under the cerebrum and behind the brain stem.
The cerebral hemispheres are divided into pairs of lobes as follows:
• Frontal—the largest lobe, located in the front of the brain. The major functions of this lobe are concentration,
abstract thought, information storage or memory, and motor function. It contains Broca’s area, which is located
in the left hemisphere and is critical for motor control of speech. The frontal lobe is also responsible in large
part for a person’s affect, judgment, personality, and inhibitions.
• Parietal—a predominantly sensory lobe posterior to the frontal lobe. This lobe analyzes sensory information
and relays the interpretation of this information to other body position in space, size and shape discrimination,
and right–left orientation.
• Temporal—located inferior to the frontal and parietal lobes, this lobe contains the auditory receptive areas and
plays a role in memory of sound and understanding of language and music.
• Occipital—located posterior to the parietal lobe, this lobe is responsible for visual interpretation and memory.
The corpus callosum, a thick collection of nerve fibers that connects the two hemispheres of the brain, is
responsible for the transmission of information from one side of the brain to the other. Information transferred
includes sensation, memory, and learned discrimination. Right-handed people and some left-handed people
have cerebral dominance on the left side of the brain for verbal, linguistic, arithmetic, calculation, and analytic
functions. The nondominant hemisphere is responsible for geometric, spatial, visual, pattern, and musical
functions. Nuclei for cranial nerves I and II are also located in the cerebrum.
The thalami lie on either side of the third ventricle and act primarily as a relay station for all sensation except
smell. All memory, sensation, and pain impulses pass through this section of the brain. The hypothalamus is
located anterior and inferior to the thalamus, and beneath and lateral to the third ventricle. The infundibulum of
the hypothalamus connects it to the posterior pituitary gland. The hypothalamus plays an important role in the
endocrine system because it regulates the pituitary secretion of hormones that influence metabolism,
reproduction, stress response, and urine production. It works with the pituitary to maintain fluid balance through
hormonal release and maintains temperature regulation by promoting vasoconstriction or vasodilatation. In
addition, the hypothalamus is the site of the hunger center and is involved in appetite control. It contains centers
that regulate the sleep–wake cycle, blood pressure, aggressive and sexual behavior, and emotional responses
(i.e., blushing, rage, depression, panic, and fear). The hypothalamus also controls and regulates the autonomic
nervous system. The optic chiasm (the point at which the two optic tracts cross) and the mammillary bodies
(involved in olfactory reflexes and emotional response to odors) are also found in this area.
The brain stem consists of the midbrain, pons, and medulla oblongata. The midbrain connects the pons and the
cerebellum with the cerebral hemispheres; it contains sensory and motor pathways and serves as the center for
auditory and visual reflexes.
The cerebellum integrates sensory information to provide smooth coordinated movement. It controls fine
movement, balance, and position (postural) sense or proprioception (awareness of position of body parts
without looking at them).
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RNSG 1538
Study Guide Exam #3
The bones of the vertebral column surround and protect the spinal cord and normally consist of 7 cervical, 12
thoracic, and 5 lumbar vertebrae, as well as the sacrum (a fused mass of 5 vertebrae), and terminate in the
coccyx.
Type of Aphasia Brain Area Involved
Auditory receptive Temporal lobe
Visual receptive Parietal & Occipital area
Expressive speaking Inferior posterior frontal areas
Expressive writing Posterior frontal area
PERIPHERAL NERVOUS SYSTEM (Med-Surg, p 1914)
The peripheral nervous system includes the cranial nerves, the spinal nerves, and the autonomic nervous system.
Twelve pairs of cranial nerves emerge from the lower surface of the brain and pass through openings in the base
of the skull. Three cranial nerves are entirely sensory (I, II, VIII), five are motor (III, IV, VI, XI, and XII), and
four are mixed sensory and motor (V, VII, IX, and X). The spinal cord is composed of 31 pairs of spinal nerves:
8 cervical, 12 thoracic, 5 lumbar, 5 sacral, and 1 coccygeal. Each spinal nerve has a ventral root and a dorsal
root. The dorsal roots are sensory and transmit sensory impulses from specific areas of the body known as
dermatomes to the dorsal horn ganglia. The sensory fiber may be somatic, carrying information about pain,
temperature, touch, and position sense (proprioception) from the tendons, joints, and body surfaces; or visceral,
carrying information from the internal organs.
The ventral roots are motor and transmit impulses from the spinal cord to the body; these fibers are also either
somatic or visceral. The visceral fibers include autonomic fibers that control the cardiac muscles and glandular
secretions.
3. Describe diagnostic tests used for assessment of suspected neurologic disorders. (Med-Surg, p 1930)
Health History
An important aspect of the neurologic assessment is the history of the present illness. The initial interview
provides an excellent opportunity to systematically explore the patient’s current condition and related events
while simultaneously observing overall appearance, mental status, posture, movement, and affect. Depending on
the patient’s condition, the nurse may need to rely on yes-or-no answers to questions, a review of the medical
record, input from witnesses or the family, or a combination of these.
Neurologic disorders may be stable or progressive, characterized by symptom-free periods as well as
fluctuations in symptoms. The health history therefore includes details about the onset, character, severity,
location, duration, and frequency of symptoms and signs; associated complaints; precipitating, aggravating, and
relieving factors; progression, remission, and exacerbation; and the presence or absence of similar symptoms
among family members.
Computed tomography (CT) scanning uses a narrow x-ray beam to scan body parts in successive layers. The
images provide cross-sectional views of the brain, distinguishing differences in tissue densities of the skull,
cortex, subcortical structures, and ventricles. Abnormalities detected on brain CT include tumor or other masses,
infarction, hemorrhage, displacement of the ventricles, and cortical atrophy
Magnetic Resonance Imaging (MRI) uses a powerful magnetic field to obtain images of different areas of the
body. The magnetic field causes the hydrogen nuclei (protons) within the body to align like small magnets in a
magnetic field. In combination with radiofrequency pulses, the protons emit signals, which are converted to
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