Walking & Neuromuscular System Flashcards
How do I initiate walking?
Reciprocal innervation through extensor & flexor neurons
Tonic excitations where a flexor neuron is excited and the extensor neuron is inhibited
This alternates
How do I initiate walking?
Central Pattern Generators
The brain sends signals via motoneurons through the spinal cord to the legs involving Central Pattern Generators
Central Pattern Generators - Assembly of neural oscillators/circuitry responsible for generating rhythmic patterns of behavior like walking
How do I initiate walking?
Multiple neural oscillators
Multiple neural oscillators flex and extend in various CPGs in the legs that generate walking
How is the fluid stepping rhythm produced?
Coordinating timing signals from Central Pattern Generator clusters command several muscles, each contracting and relaxing at phases of walking, producing fluid stepping rhythm
How do I make adjustments for varying conditions and the unexpected?
Adjustments are made through reflexes (stereotyped, unlearned responses), which adjusts the output (tension/stress) of the muscles.
How do I make adjustments for varying conditions and the unexpected?
Negative feedback loop
Adjustments occur through a negative feedback loop via the stretch receptors and the golgi tendons to either shift weight from one side to the other, or reduce force/tension
Central Pattern Generators
At the core is a set of cyclic, coordinated timing signals that are generated by a cluster of interconnected neurons.
These basic signals are used to command as many as several hundred muscles, each precisely contracting or relaxing during a particular phase of the cycle.
