Cerebellum and basal ganglia in movement
In this lesson, we’ll cover the basal ganglia and cerebellum, two structures that also play important roles in movement, along with other functions.
1) Start with this video about the cerebellum:
2) Then, read this article: Know Your Brain - Cerebellum
3) Next, watch this video about the basal ganglia:
4) Now, read this article about the basal ganglia: Know Your Brain - Basal Ganglia 5) Finally, answer these questions to test your understanding:
1. Which part of the cerebellum is MOST responsible for comparing actual limb position with the intended position during a movement?
- A. vestibulocerebellum
- B. spinocerebellum
- C. cerebrocerebellum
- D. dentate nucleus
Show Answer
Correct answer: B
The spinocerebellum receives information about limb position from the spinal cord and uses this information, for example, to compare where a limb is in space with where it should be if the movement were going as planned. If there is a discrepancy, the spinocerebellum can modify motor signals to correct any errors in the movement.
2. Which of the following regions of the cerebellum is most involved in controlling posture?
- A. lateral hemisphere
- B. primary fissure
- C. superior cerebellar peduncle
- D. vermis
Show Answer
Correct answer: D
The vermis runs along the midline of the cerebellum, and is especially involved in controlling upright posture. It receives input from the vestibular system and spinal cord and helps to regulate the muscles of the trunk that maintain posture.
3. Which of the following structures is NOT considered part of the basal ganglia?
- A. caudate
- B. putamen
- C. globus pallidus
- D. red nucleus
Show Answer
Correct answer: D
The red nucleus is found in the brainstem, and is thought to be involved in motor coordination (among other things). It is not, however, considered part of the basal ganglia. Major structures of the basal ganglia include the caudate, putamen, globus pallidus, substantia nigra, and subthalamic nucleus.
4. Which of the following is a main input area of the basal ganglia?
- A. substantia nigra pars reticulata
- B. internal globus pallidus
- C. nucleus basalis of Meynert
- D. striatum
Show Answer
Correct answer: D
Much of the information the basal ganglia receive comes from the cerebral cortex and travels first to the striatum, which is a main input area of the basal ganglia. The main output nuclei of the basal ganglia are the internal globus pallidus and the substantia nigra pars reticulata, which send projections out of the basal ganglia to the thalamus as well as to nuclei in the brainstem.
5. Which mechanism best explains how activation of the direct pathway of the basal ganglia is thought to facilitate movement?
- A. excitation of nuclei that inhibit thalamocortical activity
- B. direct excitation of motor cortex neurons by the striatum
- C. increased inhibitory signaling from the thalamus to the cortex
- D. inhibition of nuclei that inhibit thalamocortical neurons
Show Answer
Correct answer: D
The direct pathway promotes movement by inhibiting the globus pallidus internal and substantia nigra pars reticula, which normally inhibit the thalamus. This reduces inhibition of thalamocortical neurons, allowing increased cortical activity and facilitating movement.
