Article

Combining tDCS with robotic therapy is a new and promising form of
neurorehabilitation after stroke, however the effectiveness of this approach is
likely to be influenced by the relative timing of the brain stimulation and the
therapy. OBJECTIVE: To measure the kinematic and neurophysiological effects of
delivering tDCS before, during and after a single session of robotic motor
practice (wrist extension). METHODS: We used a within-subjects
repeated-measurement design in 12 chronic (>6 months) stroke survivors. Twenty
minutes of anodal tDCS was delivered to the affected hemisphere before, during,
or after a 20-minute session of robotic practice. Sham tDCS was also applied
during motor practice. Robotic motor performance and corticomotor excitability,
assessed through transcranial magnetic stimulation (TMS),
were evaluated pre- and
post-intervention. RESULTS: Movement speed was increased after motor training
(sham tDCS) by approximately 20%. Movement smoothness was improved when tDCS was
delivered before motor practice ( approximately 15%).
TDCS delivered during
practice did not offer any benefit, whereas it reduced speed when delivered after
practice ( approximately 10%). MEPs were present in approximately 50% of patients
at baseline; in these subjects motor practice increased corticomotor excitability
to the trained muscle. CONCLUSIONS: In a cohort of stroke survivors, motor
performance kinematics improved when tDCS was delivered prior to robotic
training, but not when delivered during or after training.
The temporal
relationship between non-invasive brain stimulation and neurorehabilitation is
important in determining the efficacy and outcome of this combined therapy.

Langue : ANGLAIS