Mod 10: Nervous System

Question 1

Key word parts

Neuro= nerve
Myelo= spinal cord
Meningo= meninges ( covering of spinal cord)
Duro= dura mater (
Encephalo=brain
Cerebro = cerebral
Thalamo=thalamus
Hypothalamo= hypothalamus
Cerebello= cerebellum
Cephalo=head
Encephalo= brain
Cranio= cranium or skull bones
Electro=electrical
Kinesio=movement

Suffixes
- Kiinesia,kinesis=move
-plegia=paralysis
- paresis=slight weakness/paralysis
-phasia =speech, speak
-taxia =coordination
-lysis= destruction, freeing from adhesions
-trips=crushing
-malacia =abnormal softening
-gram = X-ray
Graphy

Question 2

Structures of nervous system

• brain
• nerves
• spinal cord
• sensory organs ( eyes, ears, nose, skin,tongue)

Question 3

Divisions of the nervous system

2 primary parts

1. Central nervous system (CNS)
   - brain and spinal cord
   - receive and process info
   - regulate all bodily activity
2. Peripheral nervous system ( PNS)
   - 12 paired of cranial nerves (from brain)
   - 31 pairs of peripheral spinal nerves ( outward from spinal cord)
   - main function to transmit nerve signals to and from central nervous system
   -

Question 4

Nerves
- bundles of neurons - one or more
- tract- bundle or group of nerve fibers located within brain or spinal cord

Ganglion
- nerve centre made up of a cluster of nerve cells

Innervation
- supply of nerves to specific body part

Plexus
- network of intersecting spinal nerves / blood or lymphatic vessels
- most spinal cord plexus are named after corresponding vertebrae. Image

Receptors
- sites in sensory organs that receive external stimuli

Stimulus
- anything that excites a nerve
Impulse
- wave of excitation transmitted through nerve fibers and neurons

Question 5

Reflexes
- automatic, involuntary response to stimuli
- Eg: heart rate changes , coughing, sneezing,

Question 6

Neurons

Answer 6

• basic cells of nervous system
• the cells allow different parts of body to communicate with each other
• neurons carry nerve impulses via electrochemical process
• in the brain this electrical activity causes brain waves

Types of neurons
“ACE”
A= Afferent neurons
Also means ‘toward ‘

C = connecting neurons
E= Efferent neurons
Also means “ away from”

Functions of the above neurons
“SAM”
S= Afferent neurons also called
Sensory neurons
- emerge from sensory organs
and skin
- carry impulse from sensory
Organ ‘toward’ brain and spinal cord

A= connecting neurons are known as
Associative neurons
- links Afferent and Efferent
Neurons
M= Efferent Neurons also called
‘ motor neurons’
- motor neurons carry impulses away from brain and spinal cord towards the muscle and glands

PARTS OF NEURON
1. Dendrites
- root like processes
- receive impulses
- process is a structure that extends out of cell body

2. Axon
   - process that conducts impulses away from nerve cell
   - more than 3 feet long
   - many axons are protected by myelin sheath ( white fatty tissue covering )
3. Terminal end fibers
   - branching fibers at the end of the axon
   - lead nerve impulse from axon to synapse
4. Synapse
   - space between 2 neurons
   - or neuron and receptor organ
   - a single neuron van have few or several hundred synapses

Question 7

Neurotransmitter
- chemical substances
- that make it possible for messages to cross from
Synapse of a neuron to the target receptor

Answer 7

Neurotransmitter and Roles
1. Acetylcholine
- released at some synapses in the spinal cord and neuromuscular junctions
- influences muscle action

2. Dopamine
   - released within brain
   - excess dopamine - schizophrenia, Parkinson’s disease
3. Endorphins
   - naturally occurring substance in brain to relieve pain
4. Norepinephrine
   - affects alertness and arousal
   - inc blood pressure and heart rate
   - released glucose in response to stress
   - released by adrenal gland as flight-or-fight response
5. Serotonin
   - released in brain
   - roles in sleep, hunger, pleasure recognition

Question 8

Glial cells
- provide support and protection of neurons

Main functions

1. Surround neurons and hold them in place
2. Supply nutrients and oxygen to neurons
3. To insulate one neuron from another
4. To destroy and remove dead neurons

Question 9

Myelin sheath

• is white in colour

White matter
- when nerve fibers are covered by myelin sheath
- they are myelinated
- they look white

Gray matter
- when nerve fibers are not covered by myelin sheath they look grey
- unmyelinated

Question 10

The Central nervous system
- made up of BRAIN and SPINAL CORD

BRAIN
- protected by bones of cranium

SPINAL CORD
- protected by vertebrae of the spinal column

Answer 10

Question 11

The Meninges
- system of membranes
- encloses brain and spinal cord
- consisted of 3 layers
- Dura Mater, Arachnoid Membrane , Pia Mater

Dura Mater
- dura- hard
Mater - mother
- lines inner surface of cranium

Epidural space
- space between walls of vertebral column and dura mater
- contains fat and supportive connective tissue

Subdural space
- located between dura Mater and arachnoid membrane in skull and vertebral column

Arachnoid membrane
- 2 Ms layer of meninges
- located between dura Mater and pia mater
- loosely attached to other layers to allow blood and fluid to flow
- subarachnoid space ( space between pia mater and arachnoid membrane ) contains ‘cerebrospinal fluid ‘

Pia Mater
- 3rd layer of meninges
- located nearest to brain and spinal cord
- delicate connective tissue
- rich supply of blood vessels
Pia- means ‘tender or delicate’
Mater- mother

Question 12

Cerebrospinal fluid

• spinal fluid
• produced by special capillaries located within four ventricles in the middle region of cerebrum
  -clear fluid
• flows around brai. And spinal cord
• cools and cushions these organs
• nourish brain and spinal cord by transporting nutrients and chemical messengers to these tissues

Question 13

Parts of the brain

1. Cerebrum
   - largest and uppermost part of brain
   - controls highest level of thought,
2. Thalamus
   - located below cerebrum
3. Hypothalamus
   - located below thalamus
4. Cerebellum
   - located in lower back of cranium , under cerebrum
5. Brain stem
   - located in base of brain
   - connects brain to spinal cord
   - consists of
   
   • midbrain
   • pons
   • medulla oblangata

Answer 13

Question 14

Cerebrum
- cerebral - pertaining to the cerebrum or to brain
- cerebral cortex - made up of gray matter is outer layer of cerebrum
- made up elevated folds (Gyri)
and deep fissures (Sulci)

Cerebral hemispheres
1 Left cerebral hemisphere
- controls majority of the right side functions
- injury to left hem affects the right side of body

2. Right hemisphere- opposite to the left hem

• the crossing of nerve fibers that makes this arrangement possible occurs in the brain stem

CEREBRAL LOBE
1. Frontal lobe - skilled motor functions, memory and behaviors
2. Parietal lobe - receives and interprets nerve impulse from sensory receptors in tongue, skin and muscles

3. Occipital lobe
   - controls eyesight
4. Temporal lobe
   - controls sense of hearing , smell and the ability to create , store and access new information

Question 15

Thalamus
- located below cerebrum
- produces senses by relaying impulses to and from the cerebrum and the sense organs of body

Question 16

Hypothalamus

• located below thalamus

7 major regulatory functions
1. The autonomic nervous system- controls heart rate blood pressure , respiratory rate, digestive tract activity

2. Emotional responses - including fear and pleasure
3. Body temperature
4. Controls hunger sensation
5. Controls thirst sensation
6. Sleep- wakefulness cycle
7. Pituitary gland and endocrine system activity

Question 17

Cerebellum

• second largest part of brain
• receives incoming message regarding movement within
• joints
• muscle tone
• positions of the body
• from here messages are relayed to different parts of the brain that control the motions of the skeletal muscle
• function is to produce smooth and coordinated movements , to maintain equilibrium and to sustain normal posture

Question 18

Brain stem

• stalk like portion at the base of the brains
• connects to spinal cord

Made up of 3 parts
- mid brain
- pons
- medulla oblangata

Midbrain and pons
- provide conduction pathways to and from the higher and lower centers of brain
- controls movement of head, eyes in response to auditory and visual stimuli

Medulla oblangata
- lowest part of brain stem
- connected to spine.
- basic survival functions - heart rate, blood pressure , muscles that make possible respiration, reflexes for coughing, sneezing, swallowing , vomiting

Question 19

Spinal cord

Question 20

Peripheral nervous system
- 12 pairs of cranial nerves
- 31 pairs of spinal nerves
Peripheral- body parts that are away from center of the body

3 specialized peripheral nerves
1. Autonomic nerve fibers - carry instructions to organs and glands from the autonomic nervous system
2. Sensory nerve fibers
- receive external stimuli and transmit info to the brain
3. Somatic nerve fibers
- motor nerve fibers
- convey information that controls the body’s voluntary muscular movements

Question 21

Cranial nerves

• 12 pairs
• ## originate from under surface of brain

Question 22

Peripheral spinal nerves

Question 23

Autonomic nervous system
- controls involuntary actions of body
- internal organs
- maintain HOMEOSTASIS ( constant internal environment if the body)

2 divisions

SYMPATHETIC NERVES
- preps body for emergency
- nerves become aroused during flight or fight response

PARASYMPATHETIC NERVES
- returns body to normal after response to stress
- maintain normal body functions during ordinary circumstance

Question 24

Medical specialities

Anesthesiologist
- physician administering anesthetic agents

Anesthetist
- any medical professional who administers anesthetic agent

Neurologist
- physician - diagnosing and treating disease of the nervous system

Neurosurgeon
- nervous system surgeon

Psychiatrist

Psychologist

Question 25

Pathology of nervous system
Conditions of the head and meninges

1. CEPHAL ALGIA- headache
2. Migraine headache
3. Cluster headaches- painful headaches
   4.Encephalo cele
   -known as ‘craniocele’
   - hernia took of brain tissue through gap in skull
4. Meningocele
   - congenital herniation of meninges through skull or spinal column
   6.Hydrocephalus
   - excess spinal fluid in brain ventricles
   7.meningioma
   -slow growing benign tumor
   8.meningitis
   - inflammation of meninges

Question 26

Disorders of the brain

1. Cognition
   - mild cognitive impairment
2. Dementia
   - decline in memory
3. Vascular dementia
   - dementia caused by stroke
4. Encephalitis
   - inflammation of brain
   - viral or by rabies
   5.Reyes syndrome
   - deadly disorder
   - children
   - vomiting and confusion
5. Tetanus
   - caused by tetanus bacteria
   - also called lockjaw
   -
   7.Tourette syndrome
   - involuntary tics

Question 27

Neurodegenerative diseases

• progressive loss of structure or functions of neurons

1. Alzheimer’s
   - affects thoughts, memories and language
   - leading form of dementia

2.Huntington

3.Parkinson’s
- chronic
- muscle tremor,

4.levy body dementia
- second common type of dementia
- abnormal protein interfere with cell function

5.amyotrophic lateral sclerosis (ALS)
- Lou Gehrig disease

Question 28

Brain injuries

1 Amnesia

2. Concussion
   -Violent shaking or jarring of brain
   - tempering loss of awareness and function

3.cerebral contusion
- bruising of brain tissue
- brain bounced against rigid bone of skull

4.cranial hematoma
- collection of blood in brain tissue
- epidural hematoma( hematoma above dura Mater )
Subdural hematoma( under the dura mater )

Traumatic brain injury

1. Coup
   - injury within skull
   - hitting a windshield
   - contrecoup or counterblow is injury opposite to area of impact
2. Shaken baby syndrome

Answer 28

Question 29

Levels of consciousness

Altered level of consciousness
- decrease in consciousness due to injury, medication, drugs , alcohol

1. Conscious
2. Unconscious
   3.lethargy
   4.stupor
   -unresponsive state from which person can be aroused only briefly

5.Syncope
- also known as fainting
-

6.coma

7.vegetative state

8.Delirium
- acute condition of confusion

Question 30

Brain tumors
1. Malignant
- destroys brain tissue
-

2. Benign
   - does not invade brain tissue
3. Intracranial pressure
   - pressure inside skull
   - due to tumor, injury, improper drainage of cerebrospinal fluid
   - deprives brain of oxygen

Question 31

Strokes

• known as CVA( cerebrovascular accident )
• when blood flow to brain is obstructed
• blood vessel is blocked or ruptured

Cincinnati Prehospital Stroke Scale

Facial droop
Arm drift
Speech abnormality

Ischemic stroke
- most common type of stroke in older people
- carotid artery block
- ischemic means ‘disruption of blood supply’
- thrombotic stroke - blood clots in carotid artery
- emboli stroke -

Transient ischemic stroke
- mini stroke
- temporary interruption of blood supply to brain
- transient- passing quickly
- passes in less than an hour

Aphasia
- brain damage associated with stroke
-loss of speaking, write,comprehend

Hemorrhagic stroke
- known as bleed
- blood vessel in brain leaks
- when aneurysm (balloon like enlargement of artery wall) ruptures
- less common
- often fatal

Arteriovenous malformation
- AVM
- causes of hemorrhagic strokes
- due to abnormal connections between arteries and veins rupturing suddenly
- congenital

Question 32

Sleep disorders

Insomnia

Narcolepsy
- sudden uncontrollable brief episodes of falling asleep during the day

Sleep deprivation

Somnambulism
- sleepwalking or noctambulism

Question 33

The spinal cord
1. Myelitis
- inflammation of spinal cord
- also means inflammation of bone marrow

2. Myelosis
   - tumor of spinal cord
   - also means abnormal proliferation (increase in amount) of bone marrow tissue
3. Poliomyelitis
   - known as polio
   - highly contagious viral infection of brain stem and spinal cord
   - leads to paralysis
   - poli = gray matter
   - prevented by vaccination

4.post- polio syndrome
- polio symptoms recurrence later in life if you had childhood polio

Pinched nerves
- inflammation of root of spinal nerve

1. Radiculitis
   - also known as pinch nerve

2.cervical radiculopathy
- nerve pain caused by pressure in the spinal nerve roots in neck region

3.lumbar radiculopathy
- nerve pain in lower back caused by muscle spasms caused by compression of lumbar discs

Multiple Sclerosis
-progressive
- autoimmune disorder
- inflammation that cause demyelination of myelin sheath
- scars brain , spinal cord , optic nerve and transmission of nerve impulses

Remission- symptoms ease but disease not cured

Question 34

Nerves

Bell’s palsy
- temporary paralysis of 7th cranial nerve
- paralysis of face (only on affected side)

• inability to close eyes, pain, tearing, drooling

Guillain-Barré syndrome
- also known as ‘infectious polyneuritis’
- inflammation of myelin sheath of peripheral nerves
- rapid muscle weakness
- temporary
- rare condition
- caused by certain viral infection or immunization

Neuritis
- inflammation of nerves

Sciatica
-inflammation of sciatic nerve

Trigeminal neuralgia
- severe lightning like pain
- inflammation of 5th cranial nerve

Question 35

Cerebral palsy
- poor muscle control
- spasticity, speech defect
- damage that affects CEREBRUM
- premature low birth weight infants
- injury during pregnancy, birth or after birth

Question 36

Epilepsy and seizures

Epilepsy
- cheonic
- recurrent episodes of seizure of varying intensity
- cusually controlled with medication

Seizure
- sudden surge of electrical activity in brain
- not chronic
- short time
-due to high fever , injury to brain

Tonic-clinics seizure
- called grand mal seizure
- involves entire body
- tonic phase- rigid
- clonic phase- uncontrolled jerking

Absence seizure
- petit mal seizure
- brief disturbance in brain function
- loss of awareness often described as a staring episode

Question 37

Abnormal sensations

Causalgia
- caus= burning
- persistent, severe burning pain after an injury

Hyperesthesia
- abnormal and excessive sensitivity to touch, pain, or other sensory stimuli
- esthesia= sensation or feeling

Paresthesia
- burning , prickling sensation
- usually in arms ,legs , feet

Peripheral neuropathy
- disorder of peripheral nerves
-

Question 38

Diagnostic procedures of Nervous sys

MRI
- magnetic resonance imaging

CT
- computes tomography

Functional MRI
- detects changes in blood flow in brain while patient does an activity

Carotid ultrasonography
- ultrasound study of carotid artery
- to detect plaque in artery to predict or diagnose ischemic stroke

Echoencephalography
- ultrasound imaging to create detailed image of brain for diagnostic purpose

Electroencephalography
- recording electrical activity of brain - - through electrodes
-

Myelography
- radiographic study of spinal cord
- injection of contrast medium through lumbar puncture
- the record is called ‘myelogram’

Electromyography
- uses electrodes taped to skin
- measures transfer of electrical signals
- in peripheral nerves to muscles

Lumbar puncture
- called ‘ spinal tap’
- needle into subarachnoid space
- remove cerebrospinal fluid to diagnose injury, infection or disease

Question 39

Treatment procedures

Sedative and hypnotic medication

Hypnotic
- depresses central nervous system

Anticonvulsant
- to prevent seizures

Barbiturates
- drugs to calm or depressed effect on central nervous system
Amobarbital- sedative, hypnotic
Phenobarbital- sedative, anticonvulsant

Sedative
- depresses central nervous system
- calm, diminished responsiveness
- without sleeping

Question 40

Anesthesis
- absence of normal sensation

Anesthetic

Epidural anesthesia
- anesthetic in epidural space of the lumbar or sacral region
- numbs nerves from uterus to birth passage
- labor does not stop

General anesthesia

Local anesthesia
- inject anesthetic

Regional anesthesia
- temporary interruption of nerve conduction
- inject anesthetic near nerves

Spinal anesthesia
- anesthetic in ‘subarachnoid’ space

Local anesthesia
- spray, ointment or liquid

Question 41

The brain

Question 42

Nerves

Question 43

Mental health
Anxiety disorders

Question 44

OCD and related disorders

Question 45

Neurodevelopmental disorder

Question 46

Dissociative disorder

Question 47

Disruptive and impulse control

Question 48

Bipolar and depressive disorder

Question 49

Eating disorder

Question 50

Personality disorder

Question 51

Psychotic disorder

Question 52

Somatic symptoms disorder

Question 53

Substance related disorder

Question 54

Gender identity

Question 55

Medications

Question 56

Therapies