8. Somatic Motor Functions Flashcards
Responsible for maintaining the body’s posture and balance
Somatic motor system
Occur without conscious thought
Involuntary movements
Consciously activated to achieve a specific goal such as walking or typing
Voluntary movements
Have cell bodies in the cerebral cortex
Form descending tracts that connect to lower motor neurons
Upper motor neurons
Have cell bodies in the anterior horn of the spinal cord
Lower motor neurons
Located in the posterior portion of the frontal lobe
Primary motor cortex
Where motor functions are organized before they are actually initiated in the primary motor complex
Premotor area
The motivation and foresight to plan and initiate movements
This region is well developed only in primates esp. humans
Involved in motivation and regulation of emotional behavior and mood
Frontal area
Important in controlling the speed and precision of skilled movements in hands
Lateral corticospinal tracts
Important in planning, organizing, and coordinating motor movements and posture
Group of functionally related nuclei
Basal nuclei
Located deep within the cerebrum
Corpus striatum
Group of darkly pigmented cells in the midbrain
Stantia nigra
Slight shaking of the hands when a person is not performing a task
Resting tremor (parkinson)
Attached by cerebellar peduncles to the brainstem
Involved in maintaining balance and muscle tone
If damaged, muscle tone decreases amd fine motor movements become clumsy
Cerebellum
Major function of cerebellum
Sensing device that compares the data from two sources— motor cortex and peripheral structures
Comparator
