11. Relationships between skin sympathetic nerve activities and evoked potentials induced by voluntary or involuntary muscle contractions: Comparison between sudomotor and vasoconstrictor components

Little is known about the mechanisms responsible for activation of sympathoadrenal function during exercise. We hypothesized that sympathoadrenal discharge is activated at the onset of exercise by a reflex arising in the contracting muscle. Adrenal sympathetic nerve activity (SNA) was recorded during 1 min stimulation of the tibial nerve at two times motor threshold, before and during neuromuscular blockade, in 12 alpha-chloralose-anesthetized rats. Static muscle contractions, induced by stimulation before neuromuscular blockade, were repeated during ganglionic blockade (n = 6) to specifically test reflex activation of preganglionic activity to the adrenal gland. During static contraction, adrenal SNA rapidly increased (P less than 0.05) to a maximum of 89 +/- 12% above basal and then declined, reaching basal levels after 30 s of muscle contraction. Tibial nerve stimulation during neuromuscular blockade had no effect on adrenal SNA. In most rats, adrenal SNA decreased with ganglionic blockade, indicating postganglionic as well as preganglionic innervation of the adrenal gland. During ganglionic blockade, static muscle contractions elicited a 140 +/- 21% increase in adrenal preganglionic SNA. In conclusion, static muscle contraction reflexly increases SNA to the adrenal gland, providing a mechanism for sympathoadrenal activation at the onset of exercise.

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Task-dependent facilitation of motor evoked potentials during dynamic and steady muscle contractions

Muscle & Nerve ◽

10.1002/(sici)1097-4598(199810)21:10<1309::aid-mus10>3.0.co;2-x ◽

1998 ◽

Vol 21 (10) ◽

pp. 1309-1316 ◽

Cited By ~ 34

Author(s):

Zsuzsanna Ar�nyi ◽

Johannes Mathis ◽

Christian W. Hess ◽

Kai M. R�sler

Keyword(s):

Evoked Potentials ◽

Motor Evoked Potentials ◽

Muscle Contractions

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Pianism Retraining via Video Conferencing as a Means of Assisting Recovery from Focal Dystonia: A Case Study

Medical Problems of Performing Artists ◽

10.21091/mppa.2010.3026 ◽

2010 ◽

Vol 25 (3) ◽

pp. 126-129 ◽

Cited By ~ 1

Author(s):

Rae de Lisle ◽

Dale B Speedy ◽

John MD Thompson

Keyword(s):

Video Conferencing ◽

Muscle Contractions ◽

Focal Dystonia ◽

Full Recovery ◽

Neurological Condition ◽

Involuntary Muscle ◽

History Of

Focal dystonia (FD) is a devastating neurological condition which causes involuntary muscle contractions and often results in the loss of a musician’s playing ability. Our study investigated whether retraining via video conferencing could be helpful in the treatment of a professional pianist with a 5-year history of FD. Although full recovery was not seen, improvement was observed at slow tempi, and his hand was visibly less cramped as training sessions progressed. We conclude that video conferencing could be an acceptable medium to assist pianism retraining in pianists with FD when location prevents on-site retraining. However, in this study it did not seem as effective as previously reported, similar, one-on-one retraining in the same location.

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