Basal Ganglia - Revision Flashcards
What are the main components of the basal ganglia?
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Basal Ganglia - Revision
What are the main components of the basal ganglia?
- Caudate
- Putamen
- Globus Pallidus
- Subthalamic Nucleus
- Substantia Nigra.
Where is the caudate located?
Basal Ganglia - Revision
In the cerebrum.
What is the role of the putamen in the basal ganglia?
Basal Ganglia - Revision
The putamen, located in the cerebrum, works with the caudate as a primary input nucleus.
Identify the location and basic function of the globus pallidus.
Basal Ganglia - Revision
Located in the cerebrum, the globus pallidus acts as an output nucleus, relaying information to the thalamus.
Describe the subthalamic nucleus and its importance in the basal ganglia.
Basal Ganglia - Revision
Located inferior to the thalamus, it is part of the feedback loop that regulates movement.
Where is the substantia nigra located and what are its two major divisions?
Basal Ganglia - Revision
Located within the midbrain, it is divided into
- substantia nigra pars compacta
- substantia nigra pars reticulata
What is the role of substantia nigra pars reticulata in the basal ganglia circuit?
Basal Ganglia - Revision
It functions as an output nucleus, channeling information primarily to the thalamus.
Explain the significance of input and output nuclei in the basal ganglia.
Basal Ganglia - Revision
Input nuclei, like the caudate and putamen (striatum), receive information from the cortex and send it to the output nuclei, which then relay processed information back to the cortex via the thalamus.
How does the basal ganglia’s location affect its function?
Basal Ganglia - Revision
Located deep within the white matter of the cerebral hemispheres, it is strategically placed to influence motor control, executive functions, and emotional processes.
What is the collective term for caudate and putamen in the basal ganglia?
Basal Ganglia - Revision
They are collectively referred to as the striatum, a major input site for the basal ganglia.
What are the two primary functions of the basal ganglia?
Basal Ganglia - Revision
- Motor control
- Non-motor functions (decision making, emotional processing, and learning).
Which basal ganglia loop is responsible for initiating and suppressing movements?
Basal Ganglia - Revision
The Motor Loop
What is the function of the Oculomotor Loop within the basal ganglia?
Basal Ganglia - Revision
It helps in determining spatial attention and creating fast eye movements (saccades).
Describe the role of the Goal Directed Behavior Loop in the basal ganglia.
Basal Ganglia - Revision
It evaluates information for decision making, planning, and choosing actions.
What are the implications of a lesion in the Social Behavior Loop?
Basal Ganglia - Revision
It could lead to impulsivity, frustration, acts of violence, hypersexuality, and criminal behavior.
How does the Emotion Loop affect behavior?
Basal Ganglia - Revision
It integrates emotional processing and is involved in reward-seeking behaviors, making predictions, and potentially in addictions.
What are the symptoms of a basal ganglia stroke affecting the Emotion Loop?
Basal Ganglia - Revision
Depression, emotional blunting, and mask-like facial expressions.
How does the basal ganglia interact with the thalamus and cortex in the context of motor functions?
Basal Ganglia - Revision
It receives inputs from the cortex, processes them through its loops, and sends outputs back to the cortex via the thalamus to initiate or suppress movements.
What is the ‘Go’ pathway in the basal ganglia’s motor control?
Basal Ganglia - Revision
It activates the motor and premotor cortex, assisting with the initiation of voluntary movements.
Describe the ‘No-Go’ pathway of the basal ganglia.
Basal Ganglia - Revision
This pathway inhibits or decreases thalamocortical activation to suppress unwanted movements.
What potential cognitive deficits could arise from a caudate head infarction?
Basal Ganglia - Revision
Inattention, distractibility, disorientation, poor concentration, and short-term memory issues.
How does the basal ganglia contribute to decision making and judgment?
Basal Ganglia - Revision
Prioritizing information and executive functions.
What is the impact of the basal ganglia on learning and memory?
Basal Ganglia - Revision
It plays a role in selecting desired behaviors and learning from rewarded behaviors.
What effect does the basal ganglia have on eye movements?
Basal Ganglia - Revision
It regulates eye movements through the Oculomotor Loop, affecting how fast and accurately eyes can move to track objects.
Explain the concept of ‘desired behaviors’ in the context of the basal ganglia’s functions.
Basal Ganglia - Revision
The basal ganglia help select and facilitate actions that are deemed necessary or beneficial, while preventing undesired actions, through its intricate network of loops and pathways.
What type of eye movement is involved in the Oculomotor loop and can be impaired in pathology.
Basal Ganglia - Revision
Fast (Saccadic eye movements)
You are seeing a patient post-CVA, and they are having trouble demonstrating feelings of happiness, sadness, and other emotions due to their lack of facial expressions. What non-motor loop is affected?
Basal Ganglia - Revision
The Emotion Loop.
What is the correct order of basal ganglia circuitry for all loops?
Basal Ganglia - Revision
D. Cortex → basal ganglia → thalamus → cortex.
