Neuro-rehabilitation helps hemaparetic stroke patients confronted with loss of motor skills on one side of their body, to recover some of their motor functions after a cerebrovascular accident.
One of the most promising tracks in neuro-rehabilitation consists in amplifying the motor learning ability after a stroke, in other words how to learn (again) how to make movements with the parts of the human body impacted after a stroke. Pilot studies have shown at this matter that tDCS (transcranial direct current stimulation) - a non-invasive and painless cerebral stimulation method - allowed to modulate the cerebral activity and to increase the motor performances of patients who have been victim of stroke. This method consists of applying low voltage electric currents on the patient's head by means of electrodes during short periods of time. In 2012, a first study conducted by the teams of Professors Yves Vandermeeren and Patrice Laloux allowed to demonstrate that tDCS amplified the motor learning and the long-term motor memory of the patient after a stroke. This study was awarded with the Fernand Depelchin Prize of the Université catholique de Louvain (UCL) and allowed the CHU Neurology Team to continue its research, in particular via the use of functional Magnetic Resonance Imaging (fMRI) of the brain.
Thanks to functional MRI, this second study demonstrates that the combination of motor learning and non-invasive cerebral stimulation improves the efficiency of the cerebral activity. Indeed, one week after the placebo stimulation, the cerebral activations measured via the functional MRI was very diffuse. Large cerebral zones were somehow « recruited » although motor performance was low (poor retention). On the other hand, one week after real stimulation, the cerebral activation was focussed on the essential motor zones, almost identical to a person without stroke-impact although the motor performance was significantly better (enhanced task retention). In other words, the combination of motor learning and tDCS reinforced the essential motor zones and this specific network was reactivated one week after the real intervention.