extraoparamidal (week 13) Flashcards
what are the two main systems that are important for fine tuning and precision of movement
basal nuclei
cerebelllum
actually doing the motor component of a movement is done by motor or premotor cortex
motor
what are the 7 aspects important to voluntary movement
1) motor and premotor cortex
2) motor thalamus
3) basal ganglia
4) cerebellum
5) BS nuclei
6) SC paths
7) motor neurons
what is the function of the motor cortex
executes movements through patters of neuronal activity that descend to spinal cord (activated during the execution of movement)
the motor cortex is activated during BLANK
the execution of movement)
what is the function of the premotor cortex
organizes voluntary movement wrt sensory info, rep of motor activation, movement planning and execution
when is the premotor cortex activation
2) activation during movement PLANNING and EXECUTION
3) activated when observing movement
True or false:
the premotor cortex is only activated during planning of a movement
false, also during execution and observing a movement
what is the role of the BS in terms of movement
posture and balance (vestibulo system, Reticilospinalo )
what is the function of the cerebellum in movement
coordination and sequencing of motor activitvity, head and eye movements, posture and motor learning
what is the function of the BN (extrapyramidal) in movement
involved in motor control and modulation
involved in motor control and modulation
what system
basal n
coordination and sequencing of motor activitvity, head and eye movements, posture and motor learning
what motor system
cerebellum
posture and balance
what motor system
brainstem
organizes voluntary movement wrt sensory info, rep of motor activation, movement planning and execution
what motor system
premotor
executes movements through patters of neuronal activity that descend to spinal cord (activated during the execution of movement)
what motor system
motor cortex
what pathway controls voluntary muscle control
pyramidal
true or false: the pyramidal pathways controls involuntary muscle control
false, voluntary
where does the pyramidal pathway originate
corte
what are the 2 divisions of the pyramidal pathway
corticospinal
corticobulbar
the pyramidal pathaway start from cortex and project through where
pyramids of the medulla to the SC (cortcispinal) and brainstem/creanial n (cortibulbar)
what controls involuntary movement and modulation
extrapyramidal
true or false; the extrapyramidal pathway controls involuntary movement and modulation
true
where does the extrapyramidal pathways originate
in the brainstem (Basal ganglia)
does the extrapyramidal pathways travel through the pyramids of the medulla
no
true or false; the basal ganglia is involved in movement control and modulation
true
what are the 3 main nuclei of the nasal ganglia
1) striatum (putamen and caudate)
2) globus pallidus
3) substantial nigra
what is the important NT for the substantial nigra
dopamine
what are the 2 parts of the striautm
putamen and caudate
what are the neurons located inside the striatum
medium spiny neurons
true or false: medium spiny neurons originate in the globus pallidus
false
they originate in the striatum
where does medium spiny neurons synapse
in globus pallidus and substantie nigra
true or false: the medium spiny neurons synapse i the globus pallibus and subthalamic nuclei
false GP and substantia nigra
what are the 3 locations the medium spiny neurons receive info from
1) cortical pyramidal nueorns
2) local circuit neurons
3) dopaminergic neurons (from substantial nigra)
modulation of movement occurs from what
local circuit neurones and dopamine
the direct pathway is involved in stimulating or inhibiting movement
stimulating
the indirect pathway is involved in stimulating or inhibiting movement
inhibiting
in general, is the thalamus trying to send excitatory or inhibitory projections to the coretex
excitation (wants to stimulate movement)
in general, is the GPi (and sub nig pars reticulate) trying to send excitatory or inhibitory projections to the thalams
inhibitory (want to inhibit thalamic neurons and suppress movement)
what is the general reason that the GPi and sub nigra pars reticulate send inhibit projections to the thalamic neurons
to suppress movement
what are the aspects of the BN that inhibit the thalamus
GPi and SN pars reticula
what is the net effect on the crotex in the direct pathway
excitatory
in the direct pathway, the crotex sends excitatory or inhibitory projections to the striatum
excitatory (corticostriatal)
in the direct pathway, the striatum sends excitatory or inhibitory projections to the GPi/SN pars reticualta
inhibitory (through medium spiny neutrons)
what neurons send inhibitory information from the striatum to the GPI and SN pars reticulate
medium spiny neurones
by inhibiting the GPi, are we removing the inhibition to the thalamus, or increasing it
removing the inhibition to the thalamus
what is the general modulator of the direct pathway
SN pars compacta (sending dopamine)
in the direct pathway, does the SN parts compacta strengthen activation or inhibition
activation (want to create more movement)
pathway for direct
1) cortex sends excitatory projects to the striatum (GO WE WANT MOVEMENT)
2) striatum (via medium spiny) send a lot of inhibition signals to the GPI (becomes inhibitid)
3) GPi is inhibited, therefore sends less inhibitory signals to the thalamus)
4) thalamus is removed from tonic inhibition and can send its excitatory projections to the cortex (STIMULATES MOVEMENT)
=SN pars compacta releases dopamine that acts on D1 receptors which up regulates pathway to create more movement
under normal conditions/movement, is the subthalamic nucleus getting inhibited or activated by the GPe
inhibited (ie movement can occur)
when the subthalamic nucleus is inhibited, does movement occur or stop
movement occurs
what is the net effect on the cortex in the indirect pathway
inhibitory
explain the indirect pathway
1) cortex sends excitatory projects to the striatum (GO WE WANT MOVEMENT)
2) striatum (via medium spiny) send a lot of inhibition signals to the GPe (becomes inhibitid)
3) GPe is inhibited, therefore sends less inhibitory signals to the subthalamic nucleus)
4) subthalamic nucleus is removed from tonic inhibition and can send its
excitatory projections to the GPi and SN parts reticulate (INHIBITS) MOVEMENT)
5) thalamus is INHIBITED and cannot send its excitatory projections to the cortex (SUPPRESSES MOVEMENT)
=SN pars compacta releases dopamine that acts on D2 receptors which up downregulates pathway to suppress movement
true or false: only the direct or indirect pathway is happening at one time, not at the same time
false, tehey work together to initiate and suppress movement
the indirect and direct pathway work tgt to do what to movemn
work together to initiate and suppress movement
how is it that we can have both the indirect and direct pathway working at the same time
=they work in two diff areas of the BN
direct pathway is confused o the internal segment of the GO
indirect pathway is more diffuse covering more areas
true or false: dopamine is only excitatory in the BN pathway and explain
false, can increase or decrease activativty because there are 2 types of receptors
what are the 2 main disorders of the BN
parkinsons
huntingon
diminished movements is parkinsons or huntingtons
parkinson
excessive movements is parkinsons or huntingtons
huntingtons
what are the 4 main characters of diseases of the basal nuceli
tremor and involuntary movements (tremors at rest)
changes in posture and muscle tone
slowenes of movements but not paralysis
cognitive and behavioural disturbances
explain the different in tremors for the basal nuclei disorders vs the cerebellum disorders
BN: tremors are at rest /involntary
cerebellum: voluntary tremors during intentional movement
why is it common to see cognitive and behaviroal disturbances
because dopamine is in these pathways and we know dopamine has a role in behaviour
parkinsons is a hypo or hyper kinetic disorders
hypo
huntingon is a hypo or hyper kinetic disorders
hyper
what is the cause of parkinson
loss of neurons containing dopamine in SN (loss of domain leads to decreased activity in the direct pathway and increased activity in the indirect pathway)
what does loss of dopamine in parkinsons do to the activity of the direct and indirect pathways
decreased activity in the direct pathway and increased activity in the indirect pathway)
in parkinsons, tjære is a decreased/increased activity in the direct pathway and decreased/increased activity in the indirect pathway)
decreased in direct
indrecased in indirect
what are the 4 common symptoms of parkinson
tremor (shaking at rest, increases with stress)
rigidity (increased tone)
akinesia/bradykineasa (slow and freezing)
postural instability (high risk of falls)
true or false: in parkinsons, the tremors increase with stress
true
true or false; in parsons, the tremor does not reduce during action
false, it usually does
in parkinsons, the inhibitory projections from the striatum to the GPi is increased or decreased
decreased
in parkinsons, since the the inhibitory projections from the striatum to the GPi is decreased, does that lead to more or less tonic inhibition of thalamsu
more (decreased activity)
in parsons, does more tonic inhibition of thalamus lead to decreased or increases movement
decreases
what is the cause of huntingtons
degeneration of the striatum
=disinhibition of indirect pathway=increased activity of motor cortex
explain how in huntingtons, there is increased activity of motor cortex
lose the striatum = less inhibition to GPe
GPe can send more inhibitor signals to the Sth nucleus
subthalmaic nucleus cannot send excitatory signals to the GPi to inhibit the thalamus therefore there is more movmetn
is huntingon geentic
yes
what are the common symptoms of huntington
hypotonia
dyskinesia
athetosis
chorea
ballism
dystonia
explain hypotonia
decreased muscle done
explai dyskinesa
involuntary movemntsex
explain athetosis
slow, writhing (twisting/squirming) movements of the limbs and face
explain chorea
jerky, random movements of limbs and face
explain ballism
violent large amplitude movements
explain dystonia
sustained abrnoaml postures or slow movements
in huntington’s, there is increased activity of motor cortex through inhibition or disinhibition of the indirect pathways
disinhibtion
true or false: in end stages parkinsons or huntinton there is no more tremors or chorea
true
what is the role of the cerebllum
to detect the diff or “motor error” between intended movement and actual movement and works to reduce that error/diff
how does cerebellum influence movement
modifying activity patters of the UMN
TRUE OR FALSE; the cerebellum influences movement by modifying activity patters of the LMN
false, the UMN
disorders of the cerebellum lead to what
persistent errors in movement (disco ordination, dysmetria, cerebellar ataxia)
what are the 3 functional divisions of the cerebellum
cerebrocerebllum (in the lobes)
spinocerebellum (vermis and paranormal)
vestbulocerebbulum (floculonodular)
what is the f=role of the cerebrospinal cerbellum
motor planning
initiation of movement
motor planning
initiation of movement
which cerebellar system
cerebro
what is the role of the spine cerebellum
fine adjustments of muscle tone
motor execution nd coordination
fine adjustments of muscle tone
motor execution nd coordination
which cerebellar system
spino
what is the role of the vestibulo cerebellum
maintenance of balance, postural sway, balance during stance and gait, eye movements
maintenance of balance, postural sway, balance during stance and gait, eye movements
which cerebellar systm
vestibulo
what are the 3 main cerebellam inputs
cerebral cortex (motor ansensory) through BS nucleu
spinal cord (propricep and somatosensory)
vestibular nuclei (info on position and motion)
what type of info is send form the cerebral cortex to the cerebellum
info about motor and sensory information
what type of info is send from the SC to the cerebellum
proprioception and somatosensory info
what type of info is send from the vestibualr to the cerebellum
info on position and motion of the body
the info received from the SC to the cerebellum is from ipsialteral or contralateral side
ipsi
the info received from the vestibular nucleiu to the cerebellum is from ipsialteral or contralateral side
ipsilate
the info received from the cerebral cortex to the cerebellum is from ipsialteral or contralateral side
contralateral
the right cerebellum cording movement for right body or left body
right body (ipsilateral)
what is the main output form the cerebullum
deep cerebellar nuclei
what are the 2 projections from the deep cerebellar nuclei
to SC via vestviualr complex
to premotor an motor cortex via the UMN in brainstem and thalamic nuclei
explain the feedback loop of the cerbellum
red nuclei receives info from cerebellum and sends info back to cerebellum
leads to adaptation and motor learning
what are the 3 layers of the cerebellar cell organiastoon
granular (deep)
purkinje
molecular (less deep)
what are the 4 main important cells/fibers of the ceberullum
purkinje
granule cell
mossy fibers
climbing fibers
(basket cells = interneours)
granule cells are located in what layer
granular layer
granule cells are excitatory or inhibito
excitatory
explain projection/synapse of granule cells (general(
granule cells in deepest layer, its axons project and extend into the molecular layer and split into parallel fibers
are p[urkinje fibers inhibitory or excitatory
inhibitory
where are purkinje cells located (layer)
pukrinje layer
explain projection/synapse of granule cells (general(
dendrites of purkinje synapse with parallel fibers in the molecular layer
synapse with deep cerebellar nuclei
true or false, purkinje fibers send excitatory signals to the deep cerebellar output nuclei
false, inibitiboru
are mossy fibers excitatory or inhib
excitatory
mossy fibers get input from what general locations
motor cortex (cerebro), spinal cord (spinocerebellum, vestibular nucleu (vestibulo)
mossy fibers synapsen with what cell
granula cells
are climbing fibers excitatory or inibitor
excitatory
what is the only 2 cells of the cerbellum that are inhibitory
purkinje
basket
give am example of where climbing fibers can come from
inferior olive complex)
true or false: one climbing fibers synapses with many purkines
true
climbing fibres synapse with what cell in the cerebellum
purkinje
the granule cells split into parallel fibers in what layer
molecular
purkinje cells synapse with parallel granule cell fibers in what layer
molecular
what is the function of basket cells in the cerebllum
they are inhibitory interneours
serve to modulate inhibitory activity of purkinje
what are the 2 feedback loops of the cerebellum
deep excitatory loop (positive feedback)
cortcilar inhibitory loop (neg feedback)
explain deep excitatory loop
mossy fibers and climbing fibers (excitatory) synapse with Deep cerebellar output nuclei allowing it to send info to cerebllum outputs
=postiive feedback loop
explain cortical inhibitory llop
mossy fibers and climbing (excitatory) synapse with purkinje cells allowing it to INHIBIT cerebellar output
=negative feedback loop
what does the interplay between two cerebellar loops result in
neural sharpening of the overall motor response (allows precision of movement(
the neural sharpening is important for what
the correction of ongoing motor commands/movments
reduces movement errors
true or false: neural sharpening is important for the correction of ongoing motor commands/movments
true
are the cerebellar circuits/loops adaptable
yes, they can change
involved in motor learning
true or false: a BN lesion will lead to difficulty producing smooth, well COORDINATED movements
false, to cerebellum
true or false: in a cerebellar lesion, the movement errors will be on opposite side of the body compared to cerebellum
false, the movement errors will be on the same side of the body as the damage to the cerebellum (ipsi)
what are the 4 types of cerebellar injuries
cerebellar ataxia
vestivbulocaerebellar syndrom
cerebellar motor sundrome
cerebrocerebellum lesions
explain ncerebllar ataxia
jerky and impressive movements
jerky and impressive movements
what type of cerebellar injury
cerebellar ataxia
explain vestibulocerebeullar syndrome
difficulty standing upright and maintaining eye fixation (nystagmus)
difficulty standing upright and maintaining eye fixation (nystagmus)
what type of cerebellar injury/condition
vestibulocereballr syndrome
explain cerebellar motor syndrome
dysmetria (over.under reachin), wide based gait and shuffling, diff with rapid alternating movements (dysdiadokinesia) and tremors during voluntary movement
dysmetria (over.under reachin), wide based gait and shuffling, diff with rapid alternating movements (dysdiadokinesia) and tremors during voluntary movement
what type or cerebellar injur
cerebellar motor syndorm
true or false: in cerebellar injuries, you have tremors at rest
false, tremors during voluntary movements
explain cerebrocerebllum lesions
difficulty with speech, playing an instrument and difficulty learning new motor skills
difficulty with speech, playing an instrument and difficulty learning new motor skills
what cerebellar injury
cerebrocerebllum
what are the non motor challenges assocaited with cerebellum injuries
cognition (impaired executive functioning, visual spatial processing(
sppech
regulation of affect.mood
learning abilities (consolidator of motor learning)
