Central Nervous System Flashcards
orgnaization of CNS
1) from afferent division of peripheral nervous system => brain and spinal cord => processing => efferent division of peripheral nervous system
2) effector organs: skeletal, smooth, cardiac, endocrine, exocrine glands
neurons
1) afferent neurons
2) interneurons
3) efferent neurons
- millions of them
glial cells
1) astrocytes
2) oligodendrocytes
3) microglia
4) ependymal
- much more glial cells than neurons 90%
astrocytes
1) support neurons
2) blood brain barrier
3) transfer nutrients
4) scar tissue
5) release NT
6) brain ECF ion exchange
6) enhance synapse formatio nand synaptic transmission
7) communication
oligodendrocytes
1) myelin sheath
microglia
1) phagocytic
2) growth factor
ependymal cells
1) line internal cavities
2) cerebrospinal fluid
3) neural stem cells
brain overview
1) cerebral cortex
2) basal nuclei
3) thalamus
4) hypothalamus
5) cerebellum
6) brain stem
- midbrain
- pons
- medulla
cerebrum
1) sensory perception
2) movement
3) language
4) personality
basal nuclei
1) gray matter
2) muscle tone inhibition
2) coordination of slow movements
3) suppression of useless patterns of movement
thalamus
1) relay station for synaptic input
2) crude awareness of sensation
3) some consciousness
4) role in motor control
hypothalamus
1) homeostatic function
- thirst, urine, hunger, temperature
2) line between endocrine and nervous system
3) emotion and basic behavioral pattern
4) sleep wake cycle
cerebellum
1) balance
2) enhance muscle tone
3) skilled voluntary muscle activity
brain stem
1) peripheral cranial nerve originate here
2) CV, respiratory, digestive control
3) muscle reflexes with equilibrium and posture
4) reception and integration of synaptic input from spinal cord
5) role in sleep-wake cycle
cerebral cortex lobes
1) occipital
- primary visual cortex
2) parietal
- somatosensory cortex
3) temporal
- primary auditory cortex
4) frontal
- premotor cortex and primary motor cortex
broca’s area
1) left frontal lobe near motor area
2) speaking ability
3) broca’s aphasia
- cannot speak it out, stutter
wernicke’s area
1) left cortex at the junction of the parietal and temporal lobes
2) language comprehension of spoken and written messages
3) wernicke’s aphasia
- meaningless sound
motor cortex
1) near frontal lobe in both hemispheres
2) larger the area
- more neurons located
3) subject to changes
- use dependent competition
plasticity
1) can be changes or functionally remodeled in response to the demands placed on it
primary motor cortex
1) upper motor neurons => lower motor neurons in SC
- inhibitory signals
- lesions often lead to spastic paralysis
2) lower motor neurons in spinal cord
- lesions lead to flaccid paralysis
3) cerebellum
4) other region
- premotor cortex, thalamus, basal nuclei also regulate motor control
contralateral sensation
1) somatosensory cortex mostly receive input from opposite side
2) motor cortex primarily controls muscles on opposite side of body
amyotrophic lateral sclerosis
1) motor neuron degeneration
- both upper and lower
2) cannot control voluntary movement
- difficulty speaking, swallowing and breathing
polimyelitis
1) destroy ventral horn of lower motor neurons
- poliovirus infection
2) fever, headache, muscle pain and weakness, paralysis, muscle atrophy
3) polio vaccine
- IPV (inactivated)
- OPV (oral attenuated)
left hemisphere
1) verbal
2) logic
3) analysis
4) math
5) sequence
right hemisphere
1) rhythm
2) spatial
3) emotion
4) artistic
5) musical
6) imagination
cerebral white matter
1) communication between cerebral areas and cortex with lower CNS centers
2) association fibers
- connect parts of same hemisphere
3) commissural fibers
- two hemispheres
4) projection fibers
- connect cerebral cortex with lower CNS
limbic system
1) limbic association cortex, basal nuclei, thalamus, hypothalamus, hippocampus, and amygdala
2) emotion
3) reward and punishment
4) learning and memory
5) motivation
* work together with other regions of the brain
learning and memory
1) synapse
- AP at presynaptic neuron => calcium enters axon terminal => NT released to synaptic cleft => NT binds to receptors in post synaptic neuron => opens a specific channel
acetylcholine
1) excitatory NT
adenosine
inhibitory effect NT
cholecystokinin
1) neuropeptides
2) satiety
dopamine
1) leads to parkinson’s disease
GABA
1) brain’s main inhibitory NT
leptin
1) satiety hormone
2) inhibit appetite 3)
glutamine
1) brains main excitatory NT
ghrelin
1) hunger hormone
comparison of short term and long term memory
1) short term
- immediate storage
- seconds to hours
- limited storage
- rapid retrieval
- permanently forgotten, unless consolidated
- involves preexisting synapses
2) long term
- transferred from short term to long term
- retained days to years
- very large storage
- retrieval is slower
- usually only transiently unable to access
- formation of new synapses; synthesis of new proteins
neuroplasticity
1) changes of neural pathway and synapses due to environmental behavior and emotional processes
2) huge capacity of memory
alzheimer’s disease
1) slowly progressive impairment of memory
- dementia
2) neurodegenerative disease
- cholinergic neuron death (ones that make Ach, excitatory NT)
3) plaques
- beta-amyloid accumulate in spaces between nerve cells
4) tangles
- protein tau accumulate inside nerve cells
brain stem
1) origin of cranial nerves except CNI and CII
2) respiratory system, CV, digestive system
3) reflexes in equilibrium and posture
4) reticular formation
- integration center for signal from SC and carry to cerebral cortex
5) sleep wake cycle
parkinsons disease
1) death of neurons in substantia nigra
2) tremor, rigidity, akinesia, bradykinesia
2) neurodegenerative disease
- loss of synaptic communication
4) dopamine generating neuron death in substantia nigra in midbrain or basal nuclei
spinal cord
1) link for transmission between brain and other parts of body
2) cord can integrate reflex activity between afferent activity and efferent output
- without the brain
3) reflex (response that occurs automatically without conscious effort)
- basic
- acquired/ conditioned
