Reflex changes associated with anticipatory postural adjustments preceding voluntary arm movements in standing humans.
Dynamic changes in human stability, such as those induced by upper body movements, are preceded by anticipatory postural adjustments (APAs) in the rest of the body. We measured the excitability of the stretch reflex of the triceps-surae muscle group during APAs associated with unilateral right arm raises in standing humans. Our results demonstrate that reflex excitability and underlying muscle activity are linked during the APA period, but that they differ in their relative timing. This supports the idea that reflexes are controlled independently of muscle activation.
Vedula
Siddharth
S
Department of Biomedical Engineering, McGill University, 3775 Rue University, Montreal, QC, H3A 2B4 CANADA. siddharth.vedula@mail.mcgill.ca
Stapley
Paul J
PJ
Kearney
Robert E
RE
D001696:Biomechanical Phenomena; D004576:Electromyography / Q000295:instrumentation / Q000379:methods*; D001330:Electronic Data Processing; D004867:Equipment Design; D006801:Humans; D009068:Movement; D018482:Muscle, Skeletal / Q000473:pathology*; D009132:Muscles / Q000473:pathology; D011187:Posture; D011199:Potentiometry / Q000379:methods; D012018:Reflex; D013116:Spinal Cord / Q000473:pathology; D013997:Time Factors; D019415:Torque; D014584:User-Computer Interface