Nervous System Flashcards
What are the 5 functions of the nervous system
-Communication
-storage and processing
-sensory
- involuntary movement
-voluntary movement
What are the 2 types of nervous system cells
Neurons & neuroglia
What kind of impulses did you neurons carry
Electrical impulses
What kind of impulses do Neuroglia nerves give
They do not carry electrical impulses
They support & nourish neruros
What is the structure of a neuron
- Body
- Dentrites
- Axon
- Myelin sheath
What is the purpose of dendrite
Carry impulses into the body of the cell
What is the purpose of the axon
Carry impulses away from the body of the cell
What is the purpose of the myelin sheath
Fatty substance that covers neural axons and dendrites
What does myelin mean
Fast
Speeds up electrical impulses
An efferent neuron controls
Motor
An afferent neuron is
Sensory
What is the difference between afferent and efferent neurons
Same structure but the body of an afferent is off to the side
What do neuroglia nerves do
Support and nourish cells of the central nervous system
What is the role of glial cells of an efferent neuron
Intelligence
What is the purpose of an astrocyte
Transport nutrients to neurons
What is the purpose of oligodendrites
“Build” myelin for axons
How do astrocytes protect neurons
Governing what goes in and out of neurons
What kind of barrier is Blood brain barrier
Physical and transport
What are the 2 functions of blood brain barriers
Restricts the entrances
Transports essential nutrients and some chemicals
Do dendrites and axons of different neurons touch
No, they leave a small gap
What is the gap called between a neurons axons and a different neurons dendrites
Synaptic gap / cleft
What are neurotransmitters
Chemicals released to cross the synaptic gap
Give some examples of neurotransmitters
Adrenaline
Acetylcholine
Dopamine
Endorphins
Gaba
Glutamate
Noradrenaline
Serotonin
What does it mean to be conscious
Aware of and responds to surroundings via the senses
Define Locked-in syndrome
Wakefulness: open eyes, normal sleep wake patterns
Awareness : fully
Communicate: no body or facial movements , only eye movement
Define minimally conscious state
Wakefulness: open eyes , normal sleep wake patterns
Awareness: inconsistent
Communication: make eye contact , follow object with eyes, reach for objects , responds to command
Define the vegetative state
Wakefulness: open eyes, normal sleep wake patterns
Awareness : no evidence
Communication: no body or facial movement
Define a coma
Wakefulness: eyes not open, no sleep wake patterns
Awareness: no evidence
Communication: no body or facial movements
What are the two main divisions of the central nervous system
- Central nervous system
- Peripheral nervous system
What does the CNS consist of
- brain ( encephalon)
- spinal cord
-meninges - cerebrospinal fluid ( CSF)
What does the PNS consist of
-cranial nerves
-spinal nerves
- autonomic & somatic divisions
What does the right hemisphere of the brain control
Emotions and left handedness
What does the left hemisphere control
Language and right handedness
What separates the hemispheres
Longitudinal fissure
What connects the hemispheres
Corpus callosum
What are the 3 divisions of the brain
Forebrain
Midbrain
Hindbrain
Discuss the forebrain
Majority of brain
Discuss midbrain
Small portion of Brian beneath the forebrain
Discuss the hindbrain
Most inferior portion of brain connecting to spinal cord
what is the cerebrum
aka cortex
outer wrinkled part
what are the lobes of the cerebrum
frontal (emotions, anger)
parietal (taste)
temporal (hearing, smell)
occipital (vision)
why is the cortex wrinkled ?
to maximize surface area
when does most of the folding occur
during the 7th month of pregnancy
where is the thalamus located
19
inferior to cerebrum & corpus callosum
what is the function of the thalamus
switchboard of the brain
sorts & directs electrical impulses
sensory interpretation
where is the hypothalamus located
21
just below the thalamus
what does the hypothalamus control
certain vital signs & endocrine functions via pituitary gland
Where is the hippocampus located
18
anterior & lateral to midbrain
inferiorto thlamus
what is the function of the hippocampus
formation of long-term memories
neurons can repair & replicate here
where is the amygdala located
anterior to hippocampus
tip of hippocampus
what is the function of the amygdala
controls sympathetic and parasympathetic function
aka flight or fight
what is an “Amygdala Hijack”
cerebral cortex shuts down which controls logical thinking and planning
what is the midbrain
small portion of brainstem connecting forebrain to hindbrain
what is the function of the midbrain
communicates impulses between brainstem and spinal corn with forebrain
Where is the pons located
36
expanded area below the hypothalamus
what is the function of the pons
transmits impulses
control respiratory
where is the medulla located
directly beneath the pons
what is the function of the medulla
assist in controlling vital signs
where nerves cross R to L
where is the cerebellum located
35
expanded portion beneath occipital lobe
what is the function of the cerebellum
coordinates and smooths voluntary muscle movement
what are the layers of the meninges
Dura mater
Arachnoid mater
Pia mater
what are the spaces of the meninges
epidural space ( beneath bone & above dura mater)
subdural space ( between dura mater & arachnoid mater)
subarachnoid space ( between arachnoid & Pia mater)
what are ventricles in the brain
cavities within the brain filled with CSF
what is the role of the ventricles
communicate with subarachnoid space
what anatomy consist in the right & left lateral ventricles
16
anterior, posterior, and inferior horn, & the body
discuss the 3rd ventricle
19
beneath lateral ventricles
space between the thalamus
discuss the 4th ventricle
35e
communicates with 3rd ventricle superiorly & subarachnoid space inferiorly
where does CSF go
circulates though all ventricles & subarachnoid space of brain and spinal cord
what is the purpose of CSF
cushion CNS tissue
maintain intracranial pressure
flush toxins from CNS
where does CSF form
in the lateral ventricles about 125-150ml
what does CSF consist of
mostly plasma
few WBC NO RBC
proteins and salts
where is gray matter located
outer layer in cerebrum
why does gray matter appear gray
due to cell bodies and dendrites
what happens in gray matter
processing area of brain
no axons and myelin sheath
why does white matter appear white
presence of myelin sheath on axons
what is the function of white matter
communicating regions
no neuron cell bodies, only axons and glial cells
where is the pineal gland located
23
above midbrain cerebellum
what is the function of the pineal gland
regulates sleep cycle
where is the pituitary gland located
inferior from hypothalamus and within sella turcica
what are cranial nerves
nerves that originate from the under surface of brain
part of peripheral system
where does the optic nerve attach
attaches to posterior surface of each eye
where does the optic nerve exit
optic foramen of sphenoid
where does the optic nerve enter
medial to anterior clinoid processes
what is the optic chiasm
where the optic nerve crosses
where is the vagus nerve located
down the neck into chest and abdomen
what is the function of the vagus nerve
regulation of reparation, heart, and abdominal organs
what is vagal tone
activity of vagal nerve in regulating parasympathetic functions
-increased stress, anxiety, likley to get heart disease
what does a low vagal tone mean
increased stress, anxiety and heart disease
what is a result of paralysis of facial nerve
bells palsy
where do spinal nerve originate from
spinal cord
how many pairs of spinal nerves do we have
31
all motor and sensory
superior nerve control what part of the body
higher body parts
dorsal (posterior ) nerve roots are for what
sensory
ventral (anterior) nerve roots are for what
motor
what happens during a sudden adverse sensory event
somatic response is generated by spinal cord
what is the reflex arc
spinal cord triggers motor response
motor nerves carry immediate response stimuli muscles of effected area
peripheral nerves carry what muscle functions
involuntary
define parasympathetic nerves
“cruise control”
activates involuntary functions during normal activity
mostly cranial nerve
define sympathetic nerves
fight or flight
activate involuntary functions during emergencies
mostly spinal nerve