Operant conditioning in relation to natural EMG during rapid human walking

Area of Science:

• Neuroscience
• Biomechanics
• Motor Control

Background:

• Previous studies explored operant conditioning's effect on treadmill walking.
• This research investigates conditioning at a higher walking velocity (0.90 m/sec).

Purpose of the Study:

• To examine operant conditioning of the rectus femoris (RF) muscle during faster treadmill walking.
• To assess if learning adapts to increased contractile forces and reflex behavior.

Main Methods:

• Two subjects walked on a motor-driven treadmill at 0.90 m/sec.
• A conditioning regimen involved a visual cue after every third step, reinforced by auditory feedback.
• Electromyographic (EMG) activity in the RF muscle was recorded.

Main Results:

• Operant conditioning produced a 100-500 msec EMG burst in the RF muscle.
• Burst durations were shorter at higher velocity compared to lower speeds.
• No interference was observed from stretch reflexes or other innate behaviors.

Conclusions:

• Shorter burst durations may facilitate rapid adaptation of muscle activity to changing conditions.
• Fast walking remained well-coordinated, supporting a significant role for learning in locomotion.
• Findings suggest potential for improving pathological walking through enhanced learning.