Modulation of postural reflexes by voluntary movement1: 2. Modulation at an inactive joint

AUTOR(ES)

Gottlieb, Gerald L.

RESUMO

We have observed that there is a brief, 400 msec period of widespread facilitation of both the Hoffmann and the tendon-jerk reflexes associated with the initiation of a variety of local, voluntary, isometric efforts. It is suggested that the site of this facilitation lies within the spinal cord. We have also observed that this period is followed, for the Hoffmann reflex, by a period of spinal inhibition. By contrast, the tendon-jerk is facilitated, at a reduced level, for at least another 500 msec by mechanisms probably working at the muscle spindle. These results are discussed in comparison with experiments involving activation of the reflex agonist and antagonist muscles. It is proposed that voluntary control of the locomotor system is organized through separate mechanisms for muscle recruitment and for regulation of the sensitivity of the myotatic reflex loop.

Documentos Relacionados

• Modulation of postural reflexes by voluntary movement: 1. Modulation of the active limb
• Stretch reflex responses in the human elbow joint during a voluntary movement.
• Control of Human Voluntary Movement
• Postural adjustments associated with rapid voluntary arm movements 1. Electromyographic data.
• An inactive open complex mediated by an UP element at Escherichia coli promoters