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