Based on the available evidence , motor evoked potentials at rest were the only biomarker that predicted motor outcome in individuals with severe arm impairment following stroke .
To build an underst and ing of the neurobiology underpinning arm recovery in people with severe arm impairment due to stroke , we conducted a pooled individual data systematic review to : 1 ) characterize brain biomarkers ; 2 ) determine relationship(s ) between biomarkers and motor outcome ; and 3 ) establish relationship(s ) between biomarkers and motor recovery .
Bihemispheric brain stimulation facilitates motor recovery in chronic stroke patients
Objective : Motor recovery after stroke depends on the integrity of ipsilesional motor circuits and interactions between the ipsilesional and contralesional hemispheres . In this sham-controlled r and omized trial , we investigated whether noninvasive modulation of regional excitability of bilateral motor cortices in combination with physical and occupational therapy improves motor outcome after stroke . Methods : Twenty chronic stroke patients were r and omly assigned to receive 5 consecutive sessions of either 1 ) bihemispheric transcranial direct current stimulation ( tDCS ) ( anodal tDCS to upregulate excitability of ipsilesional motor cortex and cathodal tDCS to downregulate excitability of contralesional motor cortex ) with simultaneous physical/occupational therapy or 2 ) sham stimulation with simultaneous physical/occupational therapy .  Changes in motor impairment ( Upper Extremity Fugl-Meyer ) and motor activity ( Wolf Motor Function Test ) assessment s were outcome measures while functional imaging parameters were used to identify neural correlates of motor improvement . Results : The improvement of motor function was significantly greater in the real stimulation group ( 20.7 % in Fugl-Meyer and 19.1 % in Wolf Motor Function Test scores ) when compared to the sham group ( 3.2 % in Fugl-Meyer and 6.0 % in Wolf Motor Function Test scores ) . The effects outlasted the stimulation by at least 1 week . In the real-stimulation group , stronger activation of intact ipsilesional motor regions during paced movements of the affected limb were found postintervention whereas no significant activation changes were seen in the control group . Conclusions : The combination of bihemispheric tDCS and peripheral sensorimotor activities improved motor functions in chronic stroke patients that outlasted the intervention period . This novel approach may potentiate cerebral adaptive processes that facilitate motor recovery after stroke . Classification of evidence : This study provides Class I evidence that for adult patients with ischemic stroke treated at least 5 months after their first and only stroke , bihemispheric tDCS and simultaneous physical/occupational therapy given over 5 consecutive sessions significantly improves motor function as measured by the Upper Extremity Fugl-Meyer assessment ( raw change treated 6.1 ± 3.4 , sham 1.2 ± 1.0 )
Based on the available evidence , motor evoked potentials at rest were the only biomarker that predicted motor outcome in individuals with severe arm impairment following stroke .
To build an underst and ing of the neurobiology underpinning arm recovery in people with severe arm impairment due to stroke , we conducted a pooled individual data systematic review to : 1 ) characterize brain biomarkers ; 2 ) determine relationship(s ) between biomarkers and motor outcome ; and 3 ) establish relationship(s ) between biomarkers and motor recovery .