1. Introduction to Health science
The Nervous System
Introduction to Health science

2. Vocabulary- Combining Forms
Cerebr/o cerebrum
Encephal/o brain
Gli/o glue/ neurologic tissue
Mening/o, meningi/o meninges
Myel/o spinal cord/ bone marrow
Neur/o nerve
Psych/o mind
Spin/o spine
Tox/o, toxic/o toxic

3. Vocabulary- Prefixes and Suffixes
para near, beside, beyond
-al pertaining to
-algia pain
-cele herniation, swelling
-itis inflammation
-logist specialist
-logy study of
-lysis separation, destruction, loosening
-megaly enlargement
-oma tumor
-osis abnormal condition
-pathy disease
-tome instrument to cut
-tomy incision, to cut

4. Vocabulary- abbreviations
ANS Autonomic Nervous System
CNS Central Nervous System
CSF Cerebral Spinal Fluid
CVA Cerebral Vascular Accident (stroke)
PNS Peripheral Nervous System

5. Vocabulary
Afferent going toward the brain/ the sensory pathways
Arbor vitea tree like structure inside the cerebellum
Efferent going away from the brain/ the motor pathways
Cauda equina “horses tail” the lower end of the spinal cord bundled together
Corpus callosum bundle of nerves that connect the right and left hemispheres of the brain
Hemisphere 2 halves of brain- right and left hemisphere

6. Functions of the Nervous System
Sensation (Sensory)
Integration
Movement (Motor)

7. Functions of the Nervous System
Sensation
The ability of the nerves to detect stimuli, such as pressure, temperature changes, taste, smell or light, and send a message in the form of impulses to the brain and spinal cord.
Uses Sensory pathways, also known as Afferent pathways

8. Functions of the Nervous System
Integration
The nervous system receives and responds to internal and external sensory stimuli.
This is when it analyses and processes information. It decides if the information is important enough to act on.
Can happen in the brain or spinal cord.

9. Functions of the Nervous System
Movement
The ability of the brain to send impulses through motor nerves to muscles and glands to cause movement or secretion of hormones
Uses Motor pathways, also known as Efferent pathways.

10. Nerves are capable of sending electrical messages called impulses.
Nerves (neurons) are the basic units of structure and function for the nervous system.
Nerves are capable of sending electrical messages called impulses.
There are two main types of nerves:
Sensory (afferent)
Motor (efferent)

11. Types of Nerves
Sensory nerves which detect changes and carry impulses to the brain and spinal cord from the sense organs.
Motor nerves which detect changes and carry impulses away from the brain and spinal cord to muscles and organs.

12. There are three basic parts of a neuron:
Nerve Structure
There are three basic parts of a neuron:
Dendrites
Short, branchlike extensions which conduct electrical signals toward the cell body.
Cell Body
Contains large nucleus and other cellular organelles.
Axon
Extends from the cell body. Responsible for carrying nerve impulses to other neurons, muscles or glands.

13. Neuron
The axon may be covered with myelin sheaths that act as insulation to protect the nervous impulse and speed the transmission
Dendrites
Cell body
Myelin sheath
Axon

14. Grey and White Matter
When a neuron is covered by a myelin sheath it looks different than when it is not covered.
Grey Matter has NO Myelin Sheath
White Matter has a Myelin Sheath
Notice that in the brain the grey matter is superficial but in the spinal cord the grey matter is deep to the white matter

15. Nervous System Divisions
The largest division is between the CNS (Central Nervous System) and the PNS (Peripheral Nervous System)
The CNS contains the Brain and Spinal Cord
The PNS contains all the nerves as they exit the spine and run throughout the body

16. Nervous System Divisions
The Peripheral Nervous System can be broken down further into:
The Autonomic Nervous System (ANS) which has
the Sympathetic
the Parasympathetic
This system does most of the involuntary functions in the body
The Somatic Nervous System
This system controls the voluntary functions in the body

17. Nervous System Divisions

18. The Brain
The brain contains approximately 100 billion neurons. The brain weighs about 3 pounds. About 20% of blood leaving the heart circulates through the brain.
The brain is responsible for analyzing information, processing information and relaying messages to the rest of the body.
It is the main control center of the body.

19. Parts of the Brain Cerebrum Frontal Parietal Temporal Occipital
Cerebellum
Diencephalon
Thalamus
Hypothalamus
Brain Stem
Medulla Oblongata
Pons
Midbrain

20. The Cerebrum
The cerebrum is the largest part of the brain. It has two distinct halves called hemispheres. They are connected by a band of tissue called the corpus callosum. The cerebrum has many folds and grooves (called sulci and gyri) to increase the surface area and the number of nerves found in the brain.
The cerebrum is divided into four lobes.

21. Notice the division between the hemispheres
The sulci and gyri are obvious, and increase the surface area of the cerebrum

22. Cerebral Lobes
Frontal Lobe- controls skeletal muscle movement, interprets the sense of smell, is responsible for our personalities, and our ability to learn, think, problem solve and concentrate.
Parietal Lobe- interprets many of our senses including taste, touch, temperature, and pain.
Occipital Lobe- interprets the sense of sight.
Temporal Lobe- interprets the senses of balance and hearing. It also contains structures (such as the hippocampus) which store memory.

23. Cerebral Lobes

24. Cerebellum
The cerebellum is the second largest part of the brain. In fact, cerebellum means the “little cerebrum.” It is located inferior to the occipital lobe.
It functions to coordinate muscular movements and helps the muscles move gracefully and efficiently. It also helps with the body’s ability to balance.
The arbor vitae is the tree like structure seen when the cerebellum is dissected.

26. The Diencephalon Main structures include the
Hypothalamus
Maintains homeostasis and controls the regulation of hunger, thirst, body temperature, breathing, internal organ activity, and sleep.
Thalamus
Vision, touch (including pain, temperature, pressure), taste, hearing, and is critical for awareness.
Relays sensory information between brain regions and controls many autonomic functions of the PNS.
It also connects structures of the endocrine system with the nervous system.

27. The Diencephalon

28. The brain stem is composed of three structures Medulla Oblongata Pons
The brain stem is located inferior to the cerebellum and connects the spinal cord to the brain.
The brain stem is composed of three structures
Medulla Oblongata
Pons
Midbrain

29. The Medulla Oblongata
Is continuous with the spinal cord.
Controls autonomic functions such as heart beat, blood pressure, breathing, swallowing, hiccupping, vomiting, and gagging.
It also relays nerve impulses between the brain and the spinal cord.

30. The Pons
In Latin, the word pons literally means bridge.
It is the small bulge superior to the Medulla
It regulates the rate and depth of breathing.
Helps in the transferring of messages between various parts of the brain and the spinal cord.

31. The Midbrain
Is the nerve pathway to the hemispheres.
Deals with vision, hearing, eye movement, and body movement.

33. Midsagittal Cut of the Brain
Corpus callosum
cerebrum
Sulci
Cerebellum
Gyri
Spinal cord
Medulla oblongata
Pons
Mid brain
Diencephalon

34. The Spinal Cord
Along with the brain, it is part of the Central Nervous System.
It is the major communication link between the brain and the rest of the body.
It can process many reflexes – unconscious, automatic responses to stimuli.
There are 31 pairs of spinal nerves which branch from the spinal cord to control such processes as breathing, arm movement, and leg movement.

35. The true spinal cord ends in the upper lumbar region (L1), after that it turns into what is called the cauda equina or horses tail.
Many small individual nerves bundled together

36. Cerebrospinal Fluid
CSF is a clear, watery fluid which bathes the brain and the spinal cord to protect it by acting as a shock absorber.
CSF allows for the exchange of nutrients and waste products between the blood and the nervous tissue.
CSF circulates between the two layers of the meninges, through the center of the spinal cord, and through large openings in the brain (ventricles).

38. Meninges
A set of three layers of connective tissue that enclose the brain and spinal cord. They are located under the skull and attach directly to the brain.
Meninges help to provide a small amount of protection to the brain and spinal cord.
Cerebrospinal fluid circulates between two layer of the meninges.
The three layers
Dura mater “tough mother” outer layer
Arachnoid web like central layer
Pia mater “delicate mother” inner layer

40. Diseases and Disorders of the Nervous System
Meningitis
Meningitis is an infection that causes the inflammation of the brain and spinal cord coverings.
Symptoms include fever, chills, headache, nausea, vomiting, and stiff neck
Treatment: antibiotics for bacterial meningitis and supportive treatments for viral meningitis
There are two types
Bacterial Meningitis
Viral Meningitis

41. Epilepsy
Epilepsy is a brain disorder involving repeated seizures of any kind. Seizures are episodes of disturbed brain function that cause changes in attention or behavior.
Symptoms:
Loss of consciousness
Staring spells
Violent convulsions.
Treatment:
Varies depending on the cause.
May be controlled by medications.

42. Concussion
Post traumatic impairment of neural function caused by a direct blow to the head resulting in bruising of the brain.
Symptoms may include headache, loss of consciousness, ringing of the ears, nausea, irritability, confusion, disorientation, dizziness, amnesia or difficulty concentrating.
Treatment may include removal from play, rest avoiding re-injury, medications for pain, physical therapy and relaxation.

43. Stroke
Stroke, also known as a CVA or cerebrovascular accident, occurs when there is an interruption of the blood supply to any part of the brain.
Symptoms appear suddenly and can include weakness or paralysis of an extremity, numbness, vision changes, slurred speech, difficulty swallowing and loss of memory
It is important to get immediate care to reduce permanent complications. Physical therapy and/or occupational therapy may be needed.