Nervous System Flashcards
central nervous system
brain and spinal cord- receive and process info and regulate all bodily activity
peripheral nervous system
12 pairs of cranial nerves and 31 pairs of peripheral spinal nerves- transmit nerve signals to and from central nervous system
nerve
bundles of neurons that connect the brain/spinal cord with other parts of the body
tract
bundle or group of nerve fibers located within the brain or spinal cord
ganglion
cluster of nerve cell bodies outside the central nervous system
innervation
supply nerves to a specific body part
plexus
network of intersecting spinal nerves
receptors
sites in the sensory organs that receive external stimulation
stimulus
anything that activates a nerve and causes an impulse
reflex
automatic, involuntary response to some change
neurons
basic cells of nervous system that allow different parts of the body to communicate
ACE
SAM
Afferent neurons- toward the brain from sensory organs(sensory neurons)
Connecting neurons (associative neurons)
Efferent neurons- away from brain to muscles and glands (motor neurons)
dendrites
root-like processes that receive impulses and conduct them to cell body
axon
projection (process) that conducts impulses away from the nerve cell, usually protect by myelin sheath
terminal end fibers
branching fibers at the end of the axon that lead nerve impulse to synapse
synapse
space between 2 neurons or neuron and receptor organ
neurotransmitters
chemical substances that make it possible for messages to cross from the synapse to the target receptor
glial cells
provide support and protection for neurons 1-surround neurons and hold in place 2-supply nutrients and oxygen 3-insulate neurons from each other 4- destroy and remove dead neurons
myelin sheath
protective covering made up of glial cells - form white matter of brain and spinal cord and axon
meninges
system of membranes that enclose the brain and spinal cord - 3 layers
dura mater
outermost membrane of the meninges - thick and tough
arachnoid membrane
2nd layer of meninges, resembles spider web - loosely attached to other meninges to allow space for fluid to flow
pia mater
innermost meninges layer consisting of connective tissues with rich supply of blood vessels
cerebrospinal fluid
proceeded by special capillaries in brain to cool and cushion brain/spinal cord and transport nutrients and chemical messengers
cerebrum
largest and uppermost portion of brain responsible for all though, judgement, memory and emotion- controls and integrates motor and sensory functions
cerebral cortex
outermost layer of cerebrum - made up of gray matter- has elevated folds and deep fissures
frontal lobe
controls skilled motor functions, memory and behavior
parietal lobe
receives and interprets nerve impulses from sensory receptors in tongue, skin, and muscles
occipital lobe
controls eyesight
temporal lobe
controls the senses of hearing and smell and the ability to create, store and access new info
thalamus
produces sensations by relaying impulses to and from cerebrum and sense organs
hypothalmus
regulates:
- autonomic nervous system (heart rate, bp, breathing, digestion)
- emotional responses
- body temp
- food intake by huger sensations
- water balance by thirst
- sleep/wake cycles
- pituitary gland and endocrine system activity
cerebellum
produces smooth and coordinated movements, maintain equilibrium, and sustain normal postures
brainstem
connects cerebral hemispheres with spinal cord - 3 parts
midbrain and pons
provide pathways to and from higher and lowers centers in brain - control relaxes for eye movement and head in response to visual and auditory stimuli
medulla oblongata
controls basic survival functions
spinal cord
long fragile tube like structure which contains all the nerves affecting limbs and lower part of body
autonomic nervous system
controls involuntary actions of body, eg internal muscles functions
sympathetic nerves
prepare body for emergencies/stress by increasing respiratory rate, heart rate and blood flow to muscles
parasympathetic nerves
return body to normal after response to stress
cognition
mental activities assoc. with thinking, learning and memory
dementia
slowly progressive decline in mental abilities
vascular dementis
form of detention caused by stroke or other restriction of the flow of blood to brain
Reye’s syndrome
disorder in kids characterized by vomiting and confusion
tetanus
infection of the central nervous system caused by a toxin by bacteria
Alzheimers
leading form of dementia with progressive deterioration of memory and reasoning ability
amyotrophic lateral sclerosis
Lou Gehrig’s - rapidly progressing neurological disease that attacks nerve cells that control voluntary muscle movement
traumatic brain injury
head injury that damages the brain
levels of consciousness
describe the measurement of response to arousal and stimulus
stupor
unresponsive state from which a person can only be aroused from briefly
syncope
fainting cause by decreased blood flow to brain
cerebrovascular accident
stroke - damage to brain when blood flow to brain is disrupted due to blocked or ruptured blood vessel
ischemic stroke
blood flow to brain is blocked by the narrowing or blockage of a carotid artery
transient ischemic stroke
mini stroke - temporary interruption in blood supply to brain
hemorrhagic stroke
brain bleed - blood vessel in brain leaks or aneurysm ruptures
arteriovenous malformation
abnormal connection between arteries and veins in brain - usually congenital and can rupture suddenly at any age
myelosis
tumor on spinal cord
poliomyelitis
Polio - highly contagious viral infection of brainstem and spinal cord
radiculitis
pinched nerve - inflammation of the root of spinal nerve that causes pain and numbness radiating down the affected limb
multiple sclerosis
progressive autoimmune disease characterized by inflammation the causes demyelination of myelin sheath.
Bell’s palsy
temp paralysis of the 7th cranial nerve - causes paralysis on one side of face
Guillain-Barre syndrome
inflammation of the myelin sheath of peripheral nerves - rapidly worsening muscle weakness that can lead to temp paralysis
trigeminal neuralgia
severe, lightning-like pain in cheeks, lip and/or gums due to inflammation of 5th cranial nerve
cerebral palsy
poor muscle control, spasticity, speech defects and other neurological deficiencies due to cerebrum damage.
seizure
sudden surge of electrical activity in brain
tonic-clonic seizure
grand mal - tonic phase body is rigid, clonic phase body shakes
absence seizure
petit mal- disturbance in brain function with loss of awareness
causalgia
persistent, severe burning sensation/pain following an injury to a sensory nerve
paresthesia
burning or prickling sensation in extremities, can be 1st symptom of peripheral neuropathy
functional MRI
detects changes in blood flow in brain when patient is asked to perform specific tasks
echoencephalography
use of ultrasound imaging to create detailed visual image of brain
electroencephalography
process of recording electrical activity of brain thru use of electrodes attached to scalp
electromyography
uses electrodes taped to skin to measure the transfer of electrical signals in peripheral nerves to muscles
hypnotic medication
depresses central nervous system and usually produces sleep
barbiturates
drug class that is used as a calming or depressed effect on central nervous system
sedative
depresses central nervous system to produce calm and diminished responsiveness without sleep
spinal anesthesia
regional anesthesia produced by injecting meds into subarachnoid space
gamma knife surgery
no knife used- uses gamma radiation to destroy brain tumor
thalamotomy
incision into thalamus to kill brain cells to quiet Parkinson’s tremors
panic disorder
characterized by fear of panic attacks
dissociative disorders
when normal thought is separated from consciousness
dissociative identity disorder
formerly multiple personality disorder
personality disorder
chronic pattern of inner experience and behavior that causes serious problems with relationships and work
psychotic disorder
loss of contact with reality and deterioration of normal social functioning
catatonic behavior
marked by lack of responsiveness, stupor and a tendency to remain in a fixed position
somatic symptom disorder
physical complaints or concerns about ones body that are out of proportion to any physical findings or disease
factitious disorder
individual acts like they have a physical or mental illness when they are not really sick - motivated by desire for attention and sympathy
conversion disorder
serious temp or ongoing changes in function, like blindness or paralysis, that are triggered by psychological factors
malingering
intentional creation of false or grossly exaggerated physical or psychological symptoms motivated by incentives like avoiding work
psychotropic drug
produces temp changes affecting mind, emotions, and behavior
