1. Nervous System and Behavioral Health
Chapter 15
Nervous System and Behavioral Health

2. Objective 1: Identify organs and structures of the nervous system.
Chapter 15
Objective 1: Identify organs and structures of the nervous system.

3. Nervous System
The nervous system consists of the brain, spinal cord, and nerves, and may be divided into two parts:
central nervous system (CNS): brain and spinal cord
peripheral nervous system (PNS): cranial nerves, which carry impulses between the brain, neck, and head, and spinal nerves, which carry messages between the spinal cord and abdomen, limbs, and chest
Discuss the CNS and the PNS.

4. Brain and Spinal Cord
This is an illustration of the brain and spinal cord, which make up the central nervous system.
Note how the spinal cord ends with a branch-like structure called the cauda equina, which resembles a “horse’s tail.”

5. Function of the Nervous System
The nervous system forms a complex communication system allowing for the coordination of body functions and activities.
As a whole, the nervous system is designed to detect changes inside and outside the body, to evaluate this sensory information, and to send directions to muscles or glands in response.
This system also provides for mental activities such as thought, memory, and emotions.
Discuss the complexity of the nervous system.

6. Central Nervous System: Brain
brain: contained within the cranium, the center for coordinating body activities
cerebrum: largest portion of the brain, divided into right and left hemispheres; controls the skeletal muscles, interprets general senses (temperature, pain, and touch), and contains centers for sight and hearing. Intellect, memory, and emotional reactions also take place in the cerebrum.
Discuss the structure of the brain as a collection of sections and not just a single organ.
How does this structure benefit the human body?

7. Central Nervous System: Brain (cont’d)
ventricles: spaces within the cerebrum that contain cerebrospinal fluid (CSF), which flows through the subarachnoid space around the brain and spinal cord
cerebral spinal fluid (CSF): clear, colorless fluid to cushion the brain and spinal column from shock; transports nutrients and clears metabolic waste
Note that the common medical term ventricles is also applied to the brain.
What might be the most important function of the cerebrospinal fluid (CSF)? Why is this an important function?

8. Central Nervous System: Brain (cont’d)
cerebellum: often called the hindbrain, located under the posterior portion of the cerebrum; assists in the coordination of skeletal muscles to maintain balance.
brainstem: stem-like portion of the brain; connects with the spinal cord.
When was the function of the cerebellum first described?
Cerebellum literally means “little brain” and is a derivative of cerebrum.
Cerebellum was named in the third century BC by Erasistratus, who also named the cerebrum. Cerebellum literally means little brain and is the diminutive of cerebrum, meaning brain. Although it was named long ago, its function was not understood until the nineteenth century.
What does cerebrum mean?

9. Central Nervous System: Brain (cont’d)
pons: literally means “bridge.” It connects the cerebrum with the cerebellum and brainstem.
medulla oblongata: located between the pons and spinal cord; contains centers that control respiration, heart rate, and the muscles in the blood vessel walls, which assist in determining blood pressure.
Discuss the concept of the pons bridging various sections of the brain.
What would happen to brain function if there were no pons?
What would result from an injury to the medulla oblongata?

10. Central Nervous System (cont’d)
spinal cord
passes through the vertebral canal, extending from the medulla oblongata to the level of the 2nd lumbar vertebra; conducts nerve impulses to and from the brain and initiates reflex action to sensory information without input from the brain
Discuss how the spinal cord is the primary neural pathway in the body.
What happens to the nervous system past the second lumbar vertebra?

11. Central Nervous System (cont’d)
meninges: three layers of membrane that cover the brain and spinal cord
dura mater: tough outer layer
arachnoid: delicate middle layer; the arachnoid membrane is loosely attached to the pia mater by weblike fibers, which allow for the subarachnoid space
pia mater: thin inner layer of the meninges
The Latin translation of the first and third layers of the meninges are dura mater, meaning “hard mother,” and pia mater, meaning “soft mother.”
What do the terms hard mother and soft mother indicate about the structure of the meninges?
What is the significance of the word “mother” in describing the meninges?
Meninges were first named by a Persian physician in the tenth century. When translated into Latin, they became dura mater, meaning hard mother (because it is a tough membrane), and pia mater, meaning soft mother (because it is a delicate membrane). Mater was used because the Arabians believed that the meninges were the mother of all other body membranes.

12. Spinal Cord Showing Layers of Meninges
This is an illustration of the spinal cord showing the layers of the meninges.
Note the relationship between the dura mater and the pia mater.
Note the spinal nerve and spinal ganglia.
What is the purpose of the spinal nerve and ganglia?

13. Peripheral Nervous System
nerve: cordlike structure made up of fibers that carries impulses from one part of the body to another
12 pair of cranial nerves
31 pair of spinal nerves
ganglion: group of nerve cells located outside the central nervous system
glia: specialized cells that support and nourish nervous tissue
What is the purpose of the peripheral nervous system?
How do the peripheral nervous system and central nervous system work together?

14. Peripheral Nervous System (cont’d)
neuron: conducts nerve impulses to carry out the function of the nervous system
Note: destroyed neurons cannot be replaced
Discuss how neurons are destroyed.

15. Chapter 15
Objective 2: Define and spell word parts related to the nervous system.

16. Combining Forms of the Nervous System
cerebell/o
cerebr/o
dur/o
encephal/o
gangli/o, ganglion/o
gli/o
mening/o, meningi/o
myel/o
neur/o
radic/o, radicul/o, rhiz/o
What is the combining form for “the brain”?
What is the combining form for “nerves”?
Why are there three different combining forms for nerve root?

17. Combining Forms Commonly Used with the Nervous System
esthesi/o
ment/o, psych/o
mon/o
phas/o
poli/o
quadr/i
What does the combining form poli/o refer to?
Why are there two combining forms for “mind”?
What is the combining form for “sensation,” “sensitivity,” and “feeling”?
Notice the combining vowel for the word root quadr is “i” to make the combining form quadr/i

18. Suffixes -iatrist -iatry -ictal -paresis
What is the suffix for seizure or attack?

19. Helpful Information
The combining form myel/o is defined as spinal cord in Chapter 15, although it also means bone marrow, as presented in Chapter 14.
The suffix -paresis means slight paralysis, while the suffix -plegia means paralysis.
Note this helpful information for the combining form and suffix.

20. Review Question Which of the following means slight paralysis?
-paresis
-plegia
Answer is a) -paresis
What does the suffix –plegia mean?

21. Chapter 15
Objective 3: Define, pronounce, and spell disease and disorder terms related to the nervous system.

22. Disease and Disorder Terms Built from Word Parts
cerebellitis
cerebral thrombosis (animation on Student Evolve site)
duritis
encephalitis
encephalomalacia
encephalomyeloradiculitis
gangliitis
glioblastoma
glioma
meningioma
meningitis (animation on Student Evolve site)
meningocele
meningomyelocele
mononeuropathy
neuralgia
What is inflammation of the cerebellum?
What does encephalitis mean?
What does the term meningitis mean?
Glioma is used to describe all primary neoplasms of the brain and spinal cord.

23. Meningomyelocele
This illustration shows spina bifida and meningomyelocele.
What is the relationship between the meninges, spinal cord, and a harmful protrusion?

24. Disease and Disorder Terms Built from Word Parts (cont’d)
neuritis
neuroarthropathy
neuroma
neuropathy
poliomyelitis
polyneuritis
polyneuropathy
radiculitis
radiculopathy
rhizomeningomyelitis
subdural hematoma (animation on Student Evolve site)
What is a developing nerve cell called?
What is the difference between neuritis and polyneuritis?
What are symptoms of neurasthenia?
What is the term for an “inflammation of the nerve root, meninges, and spinal cord”?
Peripheral neuropathy refers to disorders of the peripheral nervous system, including radiculopathy, neuropathy, and mononeuropathy. The term is often used synonymously with polyneuropathy. Signs and symptoms vary and usually begin gradually, starting with tingling and numbness in the toes and spreading to the feet and upwards. Symptoms may be felt only at night, be constant, or be barely noticed by the patient. Other symptoms include numbness, loss of balance, and/or tingling.

25. Review Question
A blood clot or a piece of atherosclerotic plaque that lodges on a cerebral artery is called?
cerebral embolism
cerebral thrombosis
Answer: a) cerebral embolism
Cerebral thrombosis is a blood clot in a blood vessel of the brain.
Ischemic stroke may be caused by a cerebral embolism and cerebral thrombosis.

26. Chapter 15
Objective 5: Define, pronounce, and spell diagnostic terms related to the nervous system.

27. Diagnostic Terms Not Built from Word Parts
Diagnostic Imaging
computed tomography of the brain (CT scan)
magnetic resonance imaging of the brain or spine (MRI scan)
positron emission tomography of the brain (PET scan)
What are the similarities between a CT scan, an MRI, and a PET scan?
How would the choice of diagnostic imaging be determined?
What are EP studies, and what do they show?
The first CT unit was used in England in 1971.
The MRI was developed in England and first used in the United States in 1981.

28. Chapter 15
Objective 6: Define, pronounce, and spell complementary terms related to the nervous system.

29. Complementary Terms Built from Word Parts
anesthesia
aphasia
cephalalgia
cerebral
craniocerebral
dysphasia
encephalosclerosis
gliocyte
hemiparesis (animation on Student Evolve site)
hemiplegia
hyperesthesia
interictal
intracerebral
mental
monoparesis
monoplegia
myelomalacia
neuroid
What does the term cephalalgia mean?
What is the medical term for difficulty in speaking?
What is the difference between monoparesis and monoplegia?

30. Complementary Terms Built from Word Parts (cont’d)
neurologist
neurology
panplegia
paresthesia
postictal
preictal
quadriplegia (animation on Student Evolve site)
subdural
What does a neurologist do?
What is the difference between interictal, postictal, and preictal?

31. Types of Paralysis ________/________
Ask students to build the medical term that is illustrated is each picture.

32. Chapter 15
Objective 9: Interpret, read, and comprehend medical language in simulated medical statements, documents, and electronic health records.

33. Read Medical Terms in Use
A 78-year-old right-handed man presented to the
Emergency Department with a right hemiparesis,
expressive aphasia, and no apparent cognitive
decline. He has a history of hypertension and 2
years ago had a transient ischemic attack. A
computed tomography scan of the brain was
negative for an intracerebral hemorrhage. A
neurologist was consulted. She confirmed the
diagnosis of a ischemic stroke after magnetic
resonance imaging of the brain demonstrated an
ischemic area of the left cerebral cortex caused by a
cerebral embolism.
Ask students to pronounce and define the bolded terms.