Top-down and bottom-up stimulation techniques combined with action observation treatment in stroke rehabilitation: a perspective

Abstract

Stroke is a central nervous system disease that causes structural lesions and functional impairments of the brain, resulting in varying types, and degrees of dysfunction. The bimodal balance-recovery model (interhemispheric competition model and vicariation model) has been proposed as the mechanism of functional recovery after a stroke. We analyzed how combinations of motor observation treatment approaches, transcranial electrical (TES) or magnetic (TMS) stimulation and peripheral electrical (PES) or magnetic (PMS) stimulation techniques can be taken as accessorial physical therapy methods on symptom reduction of stroke patients. We suggest that top-down and bottom-up stimulation techniques combined with action observation treatment synergistically might develop into valuable physical therapy strategies in neurorehabilitation after stroke. We explored how TES or TMS intervention over the contralesional hemisphere or the lesioned hemisphere combined with PES or PMS of the paretic limbs during motor observation followed by action execution have super-additive effects to potentiate the effect of conventional treatment in stroke patients. The proposed paradigm could be an innovative and adjunctive approach to potentiate the effect of conventional rehabilitation treatment, especially for those patients with severe motor deficits.

Keywords: action observation; peripheral electrical stimulation; peripheral magnetic stimulation; transcranial alternating current stimulation; transcranial direct current stimulation; transcranial magnetic stimulation; transcranial random noise stimulation.

Figure 1

A schematic drawing of the two-stage stimulation model. Transcranial electrical or magnetic stimulation during action observation in a top-down manner combined with peripheral electrical or magnetic stimulation in a bottom-up manner develop into valuable physical therapy strategies in neurorehabilitation after stroke.