Lecture 20 Flashcards
(33 cards)
What does the frontal eye field (FEF) control?
Eye movements
What is the function of the premotor area (PMA)?
Controls planning and spatial guidance
What does the supplementary motor area (SMA) control?
Coordination
What is the primary motor cortex responsible for?
Causes movement with minimal stimulus
What sensory information is pooled in the posterior parietal cortex?
Sensory information transmitted to SMA and PMA
How does the brain control movement?
Isolates target of movement via sensory information and transmits it to SMA and PMA for planning
What are the descending tracts that carry signals from the primary motor cortex?
- Corticospinal tract
- Reticulospinal tract
- Rubrospinal tract
- Vestibulospinal tract
What role does the motor system serve?
Acts as a regulator comparing desired and actual position
What are the two modulatory systems for motor behavior?
- Cerebellum
- Basal ganglia
What does the traditional motor homunculus represent?
Distortion of body positions relative to cortical control
What does the modern view of motor cortex organization depict?
Density of dots indicating regional specificity
Where is the cerebellum located?
Inferior to the occipital lobe
What are the functions of the cerebellum?
- Learning muscle movements
- Influences range, rate, and force of movement
What are the components of the basal ganglia?
- Caudate nucleus
- Putamen
- Globus pallidus
What is the role of the caudate nucleus?
Body and eye movements
What type of input does the basal ganglia receive?
- Cerebral cortex
- Subthalamic nuclei
- Substantia nigra
What are the two pathways of the basal ganglia?
- Direct pathway
- Indirect pathway
What is the function of the direct pathway in the basal ganglia?
Enhances motor activity via disinhibition of the thalamus
What is the function of the indirect pathway in the basal ganglia?
Reduces motor activity via increased inhibition of the thalamus
What are the three functional divisions of the cerebellum?
- Vestibulocerebellum
- Spinocerebellum
- Corticocerebellum
What is the role of the vestibulocerebellum?
Controls eye movement, balance, and muscle tone
What is the role of the spinocerebellum?
Controls posture, balance, and anticipates future position
What is the role of the corticocerebellum?
Controls reaching rate and force, acts as a ‘break’
What is the outcome of a right-side lesion in the cerebellum?
Movement deficit most pronounced on the right side
