Article

Functional electrical stimulation (FES) may be able to augment functional arm and
hand movement after stroke. Poststroke neuroprostheses that incorporate voluntary
effort and FES to produce the desired movement must consider how forces generated
by voluntary effort and FES combine, even in the same muscle, in order to provide
an appropriate level of stimulation to elicit the desired assistive force. The
goal of this study was to determine whether the force produced by voluntary
effort and FES add together independently of effort or whether the increment in
force depends on the level of voluntary effort. Isometric force matching tasks
were performed under different combinations of voluntary effort and FES.
Participants reached a steady level of force, and while attempting to maintain a
constant effort level, FES was applied to augment the force. Results indicate
that the increment in force produced by FES decreases as the level of initial
voluntary effort increases. Potential mechanisms causing the change in force
output are proposed, but the relative contribution of each mechanism is unknown.

Langue : ANGLAIS