Brain Stimulation Enhance Post-stroke Walking Survivors and Healthy Adults

The specific aims and hypotheses are: Aim 1: To explore the trends of locomotor skill acquisition in stroke survivors after anodal tDCS (a-tDCS, real brain stimulation), stroke survivors after sham tDCS (s-tDCS), and stroke with no brain stimulation (control; CON). Hypothesis (Aim 1): Stroke participants who receives a-tDCS will show a faster rate of learning a locomotor task compared to stroke participants who receive s-tDCS and stroke participants with no brain stimulation. Aim 2: To explore different trends of stimulation-induced improvements in learning capacity and neural activities between three groups: stroke group, healthy young group, and healthy older group. Hypothesis (Aim 2): Healthy young adults will have a greater degree of stimulation-induced improvements in learning capacity and neural excitation compared to older adults and stroke participants. Aim 3: To explore the trends of functional improvements post a-tDCS in stroke survivors. Hypothesis (Aim 3): Stroke participants who receives a-tDCS will show a greater improvements in functional performances compared to stroke participants who receive s-tDCS and stroke participants with no brain stimulation. Aim 4: To explore the accumulated, longitudinal trends of a four-week visuomotor stepping training in conjunction with brain stimulation on treadmill walking training and gait improvements for persons with chronic stroke. Hypothesis (Aim 4): Stroke participants who receives a-tDCS will show a greater degree of gait improvements compared to stroke participants who receive s-tDCS and stroke participants with no brain stimulation.