Basal Ganglia Flashcards
What 3 structures help create the BG
Striatum, Globus Pallidus, Substantia Nigra, Subthalamic Nuclei
What makes up the Striatum
Caudate and Putamen
What are the 2 components of the Globus Pallidus
Internus (GPi) and Externus (GPe)
What are the 2 components of the Substania Nigra
Pars Compacts (SNpc) and Pars Reticularis (SNpr)
What are the 2 key functions for the BG
Initiation and execution of movement
What does the BG help prevent
unwanted movements through inhibitory control
What are the additional roles of the BG
Eye Movement Loop, Goal-Directed Behavior Loop, Social Behavior Loop, and Emotion Loop
What are the Major Inputs to the Striatum
Cerebral Cortex, SNpc, Thalamus, Subcortical Structures
Where is the majority of the cerebral cortex input coming from? and what are the exceptions?
Majority: frontal and parietal association areas
exception: Visual and Auditory Cortices
What are the pathways called in regards to the cerebral cortex input to the striatum?
Corticostriatal pathways
What are the major outputs from GP and SNPR
VL and VA nuclei pf thalamus, Intralaminar Nu of Thalamus, Mediodorisal Nu, Medullary & Pons Reticular Formation, Superior Colliculus
Where are the VL and Va nu of the Thalamus going to project
entire frontal lobe
-majority to PriMC, premotor area and SMA
Where is the Superior Colliculus going to project?
Eye movements BG loop
Where is DA secreted in
SNpc and VTA
What does the SNpc modulate in regards of DA
modulate striatum activity
- excitatory in the direct pathway
- inhibitory in the indirect pathway
What does the dual effect of DA allow for?
powerful decrease in suppression of thalamus by BG –> further facilitation of movement
What does ACH do in regards to DA and what causes the response
- inhibits DA when appropriate
- salient environment stimuli
What is the relevance of GABA and Glutamate with BG
Primary NT in direct and indirect pathways
What does the Oculomotor Loop control
higher control of eye movements - aids in spatial attention; initiate fast eye movements toward an object = saccadic movement
What does the Goal-Directed Behavior Loop control
decision making; goal-directed behavior; planning action selection; learning
What does the Social Behavior Loop control
recognize social cues’ regulate self-control; evaluates what information is relevant and irrelevant
What does the Limbic/Emotion Loop control
links emotions to cognitive and motor systems; reward-seeking; outcome predictions
