Stroke is a leading cause of adult motor disability. Despite
recent progress, recovery of motor function after stroke is
usually incomplete. This double blind, Sham-controlled,
crossover study was designed to test the hypothesis that
non-invasive stimulation of the motor cortex could
improve motor function in the paretic hand of patients
with chronic stroke. Hand function was measured using
the Jebsen–Taylor Hand Function Test (JTT), a widely
used, well validated test for functional motor assessment
that reflects activities of daily living. JTT measured in the
paretic hand improved significantly with non-invasive
transcranial direct current stimulation (tDCS), but not
with Sham, an effect that outlasted the stimulation
period, was present in every single patient tested and
that correlated with an increment in motor cortical
excitability within the affected hemisphere, expressed as
increased recruitment curves (RC) and reduced shortinterval
intracortical inhibition. These results document
a beneficial effect of non-invasive cortical stimulation on a
set of hand functions that mimic activities of daily living in
the paretic hand of patients with chronic stroke, and
suggest that this interventional strategy in combination
with customary rehabilitative treatments may play an
adjuvant role in neurorehabilitation.