Final Pt. 4 Flashcards
Direct and indirect pathways of cortex?
direct- corticospinal
indirect- corticobulbar
Akinesia vs dykinesia?
akinesia- absence of movement (basal ganglia)
dynkinesia- diffuculty of movement (cerebellum)
Levels of control?
Highest (precommand)- cerebellum/ basal nuclei
middle- motor cortex/ brain stem
lowest- spinal cord
primary motor cortex, premotor cortex, brocas area, frontal eye field?
PMC- precentral gyrus, relationship w/ primary somatosensory gyrus
PC- movment of several muscle groups
brocas- motor speech
FEF- voluntray eye movement
Basal ganglia requird for what?
movement initiation
Descending motor pathways?
Efferent impulses to spine from brain
direct: pyramidal
indirect: all others
Motor pathways use what neurons?
upper motor cortex neurons, lower spinal cord/crainial nerve neurons
What does pyramidal system do?
regulates fast/ skilled movement
90% lateral corticospinal
10% anterior corticospinal
How are skeletal muscles innervated?
ACh diffuses across cleft, binds
- Na/K across membrane
- Depolarization of inner muscle, AP
Parapeligia, quadrepeligia, paralysis
Parapeligia: T1 to L1
quad: cervical region
Paralysis: loss of motor function
Flaccid paralysis?
damage to ventral root, anterior horncells
- lower motor neurons damage, no impulses
- no movement at all
Spastic paralysis?
upper neurons of pri. motor cortex damaged
- spinal neurons intact
- no voluntray movement, ireegular stimulation
What tracts make up extrapyramidal system?
rubrospinal (control flexor muscles), vestibulospinal, reticulospinal (balance), tectospinal tracts (head movements)
Cerebellar processing?
The cerebellum gets data from the cortex, initiates voluntary movement, and finds the best way to perform movement
Neocerebellum?
lateral lobes of cerebellum, fine motor coordination
Midline cerebellum?
spinal inputs, posture, balance
Vestibulocerebellum?
floccondular lobe, maintains stability of head on body
What is the final common motor pathway?
lower motor neurons recive signal from direct/indirect motor neurons
sum of all inhib/exhib signals determines response of lower motor neurons/ skeletal muscles
Axons of ANS are…
2 neuron chain… pre and postganglionic
Sympathetic/ para use…
Symp use NE, para use ACh
3 pathways to paravertebral ganglia?
- synapse w/ ganglionic neuron and same ganglion
- as/decend symp. chain to synapse in other chain ganglion
- pass throuhj chain ganglion, emerge without synpasing
Hypothalamus?
Master controller of ANS, involuntray functions
2 types of cholerginic receptors?
muscarinic, nicotinic
features of nicotinic receptors?
found on motor end plates, ANS ganglions, hormone cells of adrenal medulla
ACh binding always stimulatory
features of muscarinic receptors?
efferctor cells innervated by postgang. choligeric fibers
ACh binding can be inhib/ exhib
Sympathetic vs para tone?
Symp- constricts BV, cause BP up, dilates vessels if BP too high
Para- slows heart, dictates normal level of digestive urinary systems
features of parasymp?
preganglion. long, post gang short, ganglia near viscera
features of symp?
preganglion short, post gang long, ganglia near spine
All somatic motor neurons release…
ACh (excitatory)
cholinergic vs adernegic fibers
C- parasymp. postgang. ACh releasing fibers
A- symp. postgang. axons relaseing NE
Atropine, neostigmine, tricyclic antidepress., cold, beta blockers
A- blocks parasymp. effects
N-inhibits ACh
T- prolong NE activity
C- stim. alpha-adrenergic receptors
B- attach to beta receptors, lover HR
What is the limbic system?
deal w/ emotion and memory, regualtes autonomic and endocrine based on emotion
amygdala, hippocampus, gyruses, hypothalamus
Reticular activating system?
innterconnected nuclei in brainstem, inhibited by sleep centers, keeps awake and filter info
Non-dominant hemisphere controls…
emotional components of language
3 principles of memory?
storage, processing, memory traces
short vs long term memory?
short is fleeting, limited capacity
long term is limitless
Factors that affect STM to LTM (4)
emotional state, reherasal, association, autonomic memory
Fact vs skill memory
fact: learning explicit info, stored w/ context it was learned, amyddala-hippocampus-hypothalamus
skill: motor activity, through practice, corpus striatum, motor cortex
Mechanisms of memory?
neuronal RNA content altered, dendritic spines change shape, new hippocampal neurons, extracellular proteins at synapses
stages of sleep?
awake, REM, Stage 1, stage 2 , stage 3, stage 4, cycle in and out (last 4 are NREM)
types of brain waves (4)
alpha-reg, low, indicate idiling brain
beta- rhythmic, irregular, awake/alert state
theta- more irregular, in kids
delta- high amp, deep sleep
absence vs grand mal seizures
absence- children, blank stare
grand- loose consciousness, bones may break
what happens during rem sleep?
vital signs increase, skeletal muscles inhibited, dreams
narcolepsy, insomnia, sleep apnea?
N: abrupt sleep into the wake state
I: inability to obtain necessary sleep
S: cessation of breath during sleep
What regulates the sleep cycle?
nuclei of the hypothalamus
