By using sophisticated MRI (magnetic resonance imaging) techniques, the researchers were able to "map" the positions of the stroke lesions in relation to the brain's motor system. "This helped us to very closely match the two patient groups," notes Schlaug. "Not only did the two groups of patients outwardly exhibit similar motor impairments, but we could tell from the MRIs that their lesions were positioned in similar areas of the brain. This novel approach strengthens the results, since no other between-group factor could explain the therapy's effects."

The results showed that the patients treated with tDCS exhibited a three-fold improvement in motor outcomes, such as an improved ability to grasp or perform wrist and finger movements, compared with patients who underwent physical and occupational therapy coupled with placebo stimulation. In addition, functional brain imaging showed that the therapy's effect was correlated with increased activity of the brain's non-damaged motor parts on the side of the stroke hemisphere.

"This is the first time that stimulation therapy has been administered simultaneously to both brain hemispheres and coupled with physical/occupational therapy," explains Schlaug. "Both sides of the brain play a role in recovery of function [following a stroke] and the combination of peripheral sensorimotor activities and central brain stimulation increases the brain's ability to strengthen existing connections and form new connections. It is a testament of just how plastic the brain can be if novel and innovative therapies are applied using our current knowledge of brain function."

Source: Beth Israel Deaconess Medical Center