The Basal Ganglia
80 Questions
4 Views

Choose a study mode

Play Quiz
Study Flashcards
Spaced Repetition
Chat to lesson

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

Which of the following is NOT a role of the basal ganglia?

  • Integration of sensory information (correct)
  • Motor learning
  • Motor pattern selection
  • Storage of motor plans

    • Which pathway is responsible for promoting action/movement?

  • Indirect pathway
  • Direct pathway (correct)
  • Both direct and indirect pathways
  • Neither direct nor indirect pathway

    • What happens when the firing rate of GPi/SNr is increased?

  • Motor movement is inhibited (correct)
  • Motor learning is facilitated
  • Sensory integration is enhanced
  • Motor movement is promoted

    • Which of the following is true about the firing rates of GPe neurons?

    <p>They have high tonic firing rates</p> Signup and view all the answers

    What is the effect of phasic cortical excitation on GPe firing rate?

    <p>Transient inhibition</p> Signup and view all the answers

    Which structure receives the motor plan from the thalamus and sends it back to the cortex?

    <p>Thalamus</p> Signup and view all the answers

    What is the role of dopamine from the substantia nigra in the direct pathway?

    <p>Increases firing rate of GPi/SNr</p> Signup and view all the answers

    What is the effect of phasic cortical excitation on the indirect pathway?

    <p>Transient excitation</p> Signup and view all the answers

    Which nuclei in the basal ganglia are inhibitory?

    <p>Globus pallidus</p> Signup and view all the answers

    What is the effect of disinhibition in the thalamo-cortical circuit?

    <p>Activation of movement</p> Signup and view all the answers

    Which receptor is activated by dopamine in the indirect pathway?

    <p>D2 receptor</p> Signup and view all the answers

    What is the consequence of the loss of dopamine input from the SNc?

    <p>Action selection is suppressed</p> Signup and view all the answers

    What happens in the early stage of Huntington's disease?

    <p>Excess indirect pathway output</p> Signup and view all the answers

    What is the impact of dopamine activation on the direct pathway?

    <p>Suppresses movement in the presence of strong cortical drive</p> Signup and view all the answers

    What is the role of the subthalamic nucleus (STN) in the indirect pathway?

    <p>Controls the indirect pathway</p> Signup and view all the answers

    What is the consequence of loss of striatal neurons in the indirect pathway?

    <p>Action inhibition is facilitated</p> Signup and view all the answers

    What is the main difference between hypokinetic and hyperkinetic disorders?

    <p>Indirect pathway output</p> Signup and view all the answers

    What is the net effect of the loss of DA input from the SNc?

    <p>Action selection is suppressed</p> Signup and view all the answers

    What happens in the advanced stage of Huntington's disease?

    <p>Excess direct pathway output</p> Signup and view all the answers

    What is the consequence of sustained excitotoxicity of the direct pathway?

    <p>Apoptosis of striatal neurons</p> Signup and view all the answers

    Which of the following is a role of the basal ganglia?

    <p>Generation of goal-directed voluntary movements</p> Signup and view all the answers

    What is the function of the direct pathway in the basal ganglia?

    <p>Promotes action/movement</p> Signup and view all the answers

    What is the function of the indirect pathway in the basal ganglia?

    <p>Suppresses action/movement</p> Signup and view all the answers

    What is the effect of phasic cortical excitation on GPe firing rate?

    <p>Increases GPe firing rate</p> Signup and view all the answers

    What is the impact of dopamine activation on the direct pathway?

    <p>Increases activity in the direct pathway</p> Signup and view all the answers

    What is the impact of dopamine activation on the indirect pathway?

    <p>Decreases activity in the indirect pathway</p> Signup and view all the answers

    What is the consequence of the loss of dopamine input from the substantia nigra?

    <p>Decreased activity in the indirect pathway</p> Signup and view all the answers

    What is the main difference between hypokinetic and hyperkinetic disorders?

    <p>Hypokinetic disorders result in reduced movement, while hyperkinetic disorders result in excessive movement</p> Signup and view all the answers

    What is the effect of disinhibition in the thalamo-cortical circuit?

    <p>Increases motor activity</p> Signup and view all the answers

    What is the consequence of sustained excitotoxicity of the direct pathway?

    <p>Increased activity in the direct pathway</p> Signup and view all the answers

    Which pathway is responsible for inhibiting action/movement?

    <p>Indirect pathway</p> Signup and view all the answers

    What is the consequence of loss of striatal neurons in the direct pathway?

    <p>Uncontrolled movement</p> Signup and view all the answers

    What is the effect of sustained excitotoxicity of the direct pathway?

    <p>Akinesia and rigidity</p> Signup and view all the answers

    What happens when there is loss of control of the subthalamic nucleus (STN)?

    <p>Multiple plans of movement compete with each other</p> Signup and view all the answers

    What is the main cause of Huntington's disease?

    <p>Mutation of CAG repeat</p> Signup and view all the answers

    What is the consequence of excess direct pathway output?

    <p>Uncontrolled movement</p> Signup and view all the answers

    What is the consequence of insufficient indirect pathway output?

    <p>Akinesia and rigidity</p> Signup and view all the answers

    What is the net effect of the loss of dopamine input from the SNc?

    <p>Action selection is suppressed</p> Signup and view all the answers

    What is the consequence of loss of striatal neurons in the indirect pathway?

    <p>Action inhibition is facilitated</p> Signup and view all the answers

    What is the effect of disinhibition in the thalamo-cortical circuit?

    <p>Uncontrolled movement</p> Signup and view all the answers

    Which of the following is NOT a role of the basal ganglia?

    <p>Autonomic function</p> Signup and view all the answers

    What is the consequence of insufficient indirect pathway output?

    <p>Increased movement</p> Signup and view all the answers

    What is the impact of dopamine activation on the direct pathway?

    <p>Promotes action/movement</p> Signup and view all the answers

    What is the effect of phasic cortical excitation on GPe firing rate?

    <p>Transient inhibition</p> Signup and view all the answers

    What is the consequence of the loss of dopamine input from the substantia nigra?

    <p>Decreased movement</p> Signup and view all the answers

    What is the function of the indirect pathway in the basal ganglia?

    <p>Suppresses action/movement</p> Signup and view all the answers

    What is the net effect of the loss of dopamine input from the substantia nigra?

    <p>Decreased movement</p> Signup and view all the answers

    What is the effect of disinhibition in the thalamo-cortical circuit?

    <p>Increases movement</p> Signup and view all the answers

    What is the effect of sustained excitotoxicity of the direct pathway?

    <p>Increased movement</p> Signup and view all the answers

    What happens when there is loss of control of the subthalamic nucleus (STN)?

    <p>Increased movement</p> Signup and view all the answers

    What is the consequence of loss of striatal neurons in the indirect pathway in Huntington's disease?

    <p>↑ firing of GPi neurons</p> Signup and view all the answers

    What is the consequence of loss of dopamine input from the substantia nigra in Parkinson's disease?

    <p>Direct pathway becomes less active</p> Signup and view all the answers

    What is the impact of dopamine activation on the direct pathway?

    <p>Facilitates movement in the presence of a strong cortical drive</p> Signup and view all the answers

    What is the consequence of sustained excitotoxicity of the direct pathway?

    <p>Death of neurons in the direct pathway</p> Signup and view all the answers

    What is the net effect of the loss of dopamine input from the substantia nigra in Parkinson's disease?

    <p>Action selection is suppressed</p> Signup and view all the answers

    What is the main cause of Huntington's disease?

    <p>Mutation of CAG repeat</p> Signup and view all the answers

    What is the consequence of the loss of striatal neurons in the direct pathway in Huntington's disease?

    <p>↓ inhibition of GPi</p> Signup and view all the answers

    What is the net effect of the loss of DA input from the SNc?

    <p>Action selection is suppressed</p> Signup and view all the answers

    What is the consequence of insufficient indirect pathway output in hyperkinetic disorders?

    <p>Excess direct pathway output</p> Signup and view all the answers

    What is the main difference between hypokinetic and hyperkinetic disorders?

    <p>Insufficient direct pathway output vs. excess direct pathway output</p> Signup and view all the answers

    Which of the following is NOT a role of the basal ganglia?

    <p>Autonomic function regulation</p> Signup and view all the answers

    What is the impact of dopamine activation on the direct pathway?

    <p>Promotes action/movement</p> Signup and view all the answers

    What is the consequence of sustained excitotoxicity of the direct pathway?

    <p>Promotes action/movement</p> Signup and view all the answers

    What is the effect of phasic cortical excitation on GPe firing rate?

    <p>Transient inhibition</p> Signup and view all the answers

    What is the consequence of the loss of dopamine input from the substantia nigra?

    <p>Suppresses action/movement</p> Signup and view all the answers

    What is the main difference between hypokinetic and hyperkinetic disorders?

    <p>Hypokinetic disorders involve reduced movement, while hyperkinetic disorders involve excessive movement.</p> Signup and view all the answers

    What is the consequence of the loss of striatal neurons in the indirect pathway in Huntington's disease?

    <p>Suppresses action/movement</p> Signup and view all the answers

    What is the effect of disinhibition in the thalamo-cortical circuit?

    <p>Increases movement</p> Signup and view all the answers

    What is the net effect of the loss of dopamine input from the substantia nigra?

    <p>Suppresses action/movement</p> Signup and view all the answers

    What is the consequence of the loss of dopamine input from the substantia nigra in Parkinson's disease?

    <p>Suppresses action/movement</p> Signup and view all the answers

    What is the consequence of loss of striatal neurons in the indirect pathway in Huntington's disease?

    <p>Choreiform symptoms</p> Signup and view all the answers

    What is the consequence of insufficient indirect pathway output in hyperkinetic disorders?

    <p>Uncontrolled movement</p> Signup and view all the answers

    What is the consequence of the loss of dopamine input from the substantia nigra in Parkinson's disease?

    <p>Akinesia and rigidity</p> Signup and view all the answers

    What is the effect of disinhibition in the thalamo-cortical circuit?

    <p>Increased firing of thalamo-cortical neurons</p> Signup and view all the answers

    What is the main difference between hypokinetic and hyperkinetic disorders?

    <p>Excess indirect pathway output in hypokinetic disorders</p> Signup and view all the answers

    What is the consequence of sustained excitotoxicity of the direct pathway?

    <p>Excessive uncontrolled movement</p> Signup and view all the answers

    What is the impact of dopamine activation on the indirect pathway?

    <p>Inhibition of the indirect pathway</p> Signup and view all the answers

    What is the net effect of the loss of DA input from the SNc?

    <p>Suppression of action selection</p> Signup and view all the answers

    What is the consequence of loss of striatal neurons in the direct pathway?

    <p>Akinesia and rigidity</p> Signup and view all the answers

    What is the effect of phasic cortical excitation on GPe firing rate?

    <p>Hyperactive GPe</p> Signup and view all the answers

    Study Notes

    Basal Ganglia Overview

    • Basal ganglia contribute to the control of voluntary motor movements, procedural learning, routine behaviors, and emotions.
    • Functions include action selection, motor planning, and modulation of movement.

    Pathways Involved

    • Direct pathway promotes action and movement; facilitates desired motor plans.
    • Indirect pathway inhibits action and movement; suppresses unwanted motor plans.

    Neuronal Firing Rates

    • Increased firing rate of GPi/SNr leads to enhanced inhibition of thalamic outputs, reducing movement initiation.
    • GPe neurons typically exhibit significant variability in firing rates; they communicate inhibitory signals.
    • Phasic cortical excitation decreases GPe firing rate, reducing its inhibitory output.

    Dopamine's Role

    • Dopamine from the substantia nigra plays a key role in modulating the direct pathway, facilitating movement.
    • In the indirect pathway, dopamine activates D2 receptors, reducing the activity of the pathway.
    • Loss of dopaminergic input from SNc results in increased inhibition of thalamic activity, leading to bradykinesia in disorders like Parkinson's disease.

    Huntington's Disease

    • Early stages are characterized by loss of striatal neurons, specifically in the indirect pathway, leading to hyperkinetic movements.
    • Advanced stages result in severe motor control impairment and further neuronal loss.
    • The main cause of Huntington's disease is genetic mutation leading to neurodegeneration.

    Thalamo-Cortical Circuits

    • Disinhibition in thalamo-cortical circuits enhances cortical activation and leads to increased motor activity.
    • Loss of striatal neurons in the indirect pathway contributes to hyperkinetic disorders, characterized by excessive movement.

    Hypokinetic vs Hyperkinetic Disorders

    • Hypokinetic disorders (e.g., Parkinson's) involve reduced movement due to loss of dopamine input and increased basal ganglia inhibition.
    • Hyperkinetic disorders (e.g., Huntington's) exhibit excessive movement due to impaired function of the indirect pathway and reduced inhibitory control.

    Consequences of Neuronal Loss

    • Loss of striatal neurons in the direct pathway leads to diminished ability to initiate voluntary movements, contributing to hypokinesia.
    • Sustained excitotoxicity in the direct pathway may result in significant neuronal damage and loss of motor control.

    Summary of Dopamine Effects

    • Activation of the direct pathway by dopamine facilitates movement.
    • Insufficient dopaminergic activity negatively impacts both direct and indirect pathways, contributing to motor disorders.
    • Control over the subthalamic nucleus (STN) is crucial for balanced movement initiation and suppression.

    Overall Effects of Dysfunction

    • The net effect of dopamine loss from the substantia nigra leads to a predominance of the indirect pathway activity, resulting in reduced movement capability and rigidity.

    Studying That Suits You

    Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

    Quiz Team

    Related Documents

    Lecture 10: Function & Dysfunction of Basal Ganglia PDF

    Description

    Test your knowledge on the function and dysfunction of the basal ganglia. Explore its role in generating goal-directed voluntary movements, motor learning, motor pattern selection, and more.

    More Like This

    Basal Ganglia and Neuroanatomy Quiz
    18 questions

    Basal Ganglia Anatomy Quiz: Test Your Knowledge

    RichTourmaline9881 avatar
    RichTourmaline9881
    Basal Ganglia Functions and Nuclei
    29 questions

    Basal Ganglia Functions and Nuclei

    ThrivingGallium3808 avatar
    ThrivingGallium3808
    Basal Ganglia and Motor Control System
    24 questions

    Basal Ganglia and Motor Control System

    CherishedMoscovium1923 avatar
    CherishedMoscovium1923
    Control de los Movimientos y Ganglios Basales
    25 questions

    Control de los Movimientos y Ganglios Basales

    PropitiousOrientalism avatar
    PropitiousOrientalism
    Use Quizgecko on...
    Browser
    Open
    Browser
    Browser