Neuro control of gait Flashcards
Describe Central Pattern Generators
CPGs control the rhythmic activation and deactivation of extensors and flexors in gait at the level of the spinal cord. Each CPG is divided into two half centres, one of which is devoted to flexion and one to extension. Inhibitory interneurons inhibit both from firing at the same time.
What is phase switching in CPGs?
A fatigue process gradually diminishes excitation until the inhibitory interneuron falls below a critical level and releases the opposite half centre from inhibition.
If the rest of the CNS is disconnected from the spinal cord, what happens with gait?
Rhythmic gait activation patterns continue but require external stimulation to initiate.
What are the 3 main functions of the brainstem for gait?
Postural control (weight support), muscle tone, and initiation of locomotion.
What happens to gait when MLR is stimulated more intensely?
Increased speed and force of propulsion. Mode progression.
What is the role of the reticular formation/pons in gait?
Postural control via the integration of vestibular and proprioceptive sensory information.
What is the role of the cerebellum in gait and what happens if it is damaged?
Comparison of intended and actual movement pattern using sensory info and fine tuning of motor neurons to edit the movement closer to intended pattern. Damage causes ataxia (uncoordinated movement) including tremor, imbalance, and dysmetria.
What is the role of the basal ganglia in gait?
Initiation of gait via stimulation of the MLR.
What is the role of the cerebral cortex in gait?
Adapt to environmental stimuli to produce optimal gait.
3 key senses in gait control?
Vision, proprioception, and vestibular.
2 key inputs for transition from stance to swing phase.
Hip flexor stretch and unloading.
