Basal ganglia Flashcards
What is one of the largest roles of the BG?
decision to move
The BG modulates _______ motor activity.
voluntary
The balance of ______ and ______ pathways gives input to the thalamus and from there to the cortex
inhibitory; excitatory
What are the 3 parallel circuits in the BG?
- motor circuit
- associative circuit
- limbic circuit
______ circuit: controls body and eye movements
motor
_______ circuit: involved in higher level cognitive function
associative
________ circuit: involved in emotional and motivational processing
limbic
In the BG, all 3 circuits are integrated into 1 which is why we are not able to multitask (T/F).
TRUE
The activity of the BG encodes for the ________ to move, _______ and ________ of movement.
decision; direction; amplitude
The BG encodes for the motor expression of _______.
emotions
The BG makes movements and behaviours more efficient (_________).
proceduralization
The thalamus is under chronic _______ when we are not moving.
inhibition
The ______ pathway releases the tonic inhibition of the thalamus, leading tom ore excitation of the motor cortex, and more motor output.
direct
The _______ pathway inhibits output from the thalamus, leading to less excitation of the motor cortex, and less motor output.
indirect
In the basal ganglia, the input is to the ______ and _____, and the output is from the ____ ______.
caudate; putamen; globus pallidus
What are the two options in the BG in terms of output?
- increase the inhibition
2. inhibit the inhibition
Inhibiting inhibitory neuron from the GPi = releasing inhibition to the thalamus = _____ pathway
direct
Enhancing inhibition of the thalamus = _______ pathway.
indirect
In the ______ pathway, there is an excitation of the caudate and putamen leading to inhibition of the GPi.
direct
The ______ pathway released the upper motor neurone form their tonic inhibition, leading to an ______ in motor output.
direct; increase
The direct pathway facilitates _____-______ movement,
target-oriented
In the direct pathway, there is an ______ of the sub thalamic nucleus, leading to ______ of the GPi, and further ________ of the thalamus.
inhibition; excitation; inhibition
The indirect pathway puts a _____ on the normal function of the direct pathway, resulting in a _______ of motor output.
brake; reduction
The indirect pathway inhibits potentially _______ movements.
competing
Direct and indirect pathways are happening _________.
simultaneously
Target-oriented, efficient movements are facilitated (______ pathway) and superfluous competing movements are inhibited (______ pathway).
direct; indirect
Parkinson’s disease is an example of _______ of motor output.
inhibition
Ballism and Huntington’s ideas are example of _______ motor output.
excessive
_______ = sudden uncontrolled flinging movements of the exutermities
ballism
Usually ballism occurs only on one side (_________)
hemiballism
Underlying ballism is a lesion of the ________ _______ nucleus.
contralateral sub thalamic
In hemi-ballism, there is a los of the _______ pathway.
indirect
Will a stroke of the L subthalamic nucleus lead to the loss of indirect pathway and suppression of superfluous movement on the L or the R side?
R !
_________ disease leads to deficits in cognition, behaviour and a characteristic hyperkinetic movement disorder
huntingtons
Huntington’s = degernation of the ________.
striatum (caudate and putamen)
Doest Huntington’s effect the direct or indirect pathway?
Both!
_________ = degeneration of dopaminergic neurons of the substantia nigra
parkinsons
Parkinson’s leads to decrease in movement (________) or loss of movement (________.
hypokinesia; akinesia
Parkinson’s leads to loss of facial expression (_______).
hypomimia
Damage to the substantial nigra effects both the direct and indirect pathways (T/F).
TRUE
In Parkinson’s disease, there is ____ inhibition of the tonic inhibition of the thalamus, so target oriented and efficient movements are not facilitated.
less
In Parkinson’s disease, the GPe is _______, less inhibitory input to the STN, more ________ input to the GPi, more ________ of the thalamus.
inhibited; excitatory; inhibition
What are three parallel circuits in the BG?
- motor
- associative or cognitive
- limbic
In the _______ circuit, both direct and indirect pathways are involved.
motor
The _______ circuit participate in planning complex motor activity.
associative
When a novel task has been practiced and well learned, activity in the ______ circuit decreases and the ______ circuit becomes more active.
associative; motor
Limbic circuit = motor expression of ______.
emotion
The limbic system is rich in _________ neurons.
dopaminergic
The limbic circuit neurons project back to the motor cortex (T/F).
FALSE
