Chapter 18 Integration of motor control

cortical motor system

• network of cortical areas comprising the UMNs which sends info to the LMNs

  • Under the influence of cerebellum & basal ganglia and sensory information 

  • Movement can be precise, target oriented, and efficient; contains emotional output; and respond to changes in sensory input and the environment.

vestibular nuclei

• postural and movement adjustment and keeps the body oriented with the head when the head changes positions

reticular formation

• emporal and spatial coordination of movement and the maintenance of postural stability

• Locomotion and postural control; modulates muscle tone

red nucleus

• relay and processing station of info from the cerebellum and thalamus; located in the midbrain

LMN system

• the final common pathway for signal transduction to the skeletal muscles

  • Circuitry within the anterior horn of the spinal cord

basal ganglia

• Receive cortical and limbic input then project back to the cortex through 3 functional loops:

  • Motor, cognitive, limbic

  • Loops are integrated into behavior: motor output, cognition, emotions

• Ensures that movements are planned & executed precisely

3 loops

Motor

cognitive

limbic

differential diagnosis

1. Spasticity with brisk deep tendon reflexes (DTRs)

2. Rigidity with hypokinesia

3. Reduced ankle DTRs bilaterally with plantar flexion weakness