Effect of nerve block on sural amplitude during remote muscle contraction.

We previously reported that the median sensory nerve action potentials (SNAPs) increased in amplitude during both near (3) and remote (4) muscle contraction. The objective of the present project was to begin to study the pathway by which this occurred. The sural amplitude was measured after one min.

Late facilitation of the human soleus H reflex induced by sustained isometric maneuver.

Studying the effect of spinal cord reinforcement maneuvers (SCRMs) on H reflex assists in understanding aspects of motor control. Our objective was as follows: (1) to elucidate the effects of four neck positions (neck resting at neutral position (control); passive hyperflexion of the neck; hyperextension of the neck with simultaneous abdominal contraction; and sustained active neck hyperflexion); (2) to evaluate the temporal changes of soleus H reflexes repeatedly evoked after a period of sustained neck flexion. We used a prospective, intrinsically controlled trial of the effects of these SCRMs on the H reflexes and M-responses in ten healthy volunteers.

Augmented sensory nerve action potentials during distant muscle contraction.

We previously reported that the median sensory nerve action potentials (SNAP) increased in amplitude during ipsilateral abductor pollicis brevis contraction. The objectives of the present project were to study the timing and origin of this phenomenon and to eliminate the possibility of local artifact. Ten normal subjects were recruited.