Spinal cord stimulation as a novel neuromodulation strategy for enhancing language recovery in post-stroke aphasia: a hypothesis

Abstract

Post-stroke aphasia is a debilitating language disorder that significantly impairs communication and quality of life. Although speech therapy and non-invasive brain stimulation techniques such as repetitive transcranial magnetic stimulation (rTMS) and transcranial direct current stimulation (tDCS) have shown clinical benefit, treatment responses remain variable and incomplete. We hypothesize that spinal cord stimulation (SCS), encompassing invasive epidural SCS (eSCS) and two mechanistically distinct non-invasive transcutaneous modalities, transcutaneous spinal direct current stimulation (tsDCS) and transcutaneous spinal pulsed current stimulation (tsPCS), may enhance language recovery in patients with post-stroke aphasia. Unlike cortical stimulation, spinal neuromodulation may engage ascending sensory pathways and propriospinal networks that influence distributed cortical systems. A series of small-sample studies conducted by the same research team has suggested that tsDCS combined with language therapy may confer benefits in post-stroke aphasia. We propose that SCS may enhance cortical excitability and functional connectivity within residual language networks through spinal–cortical interactions, thereby augmenting neuroplasticity and improving language outcomes when paired with behavioral therapy. This hypothesis predicts measurable improvements in naming, fluency, and comprehension beyond standard rehabilitation. If confirmed, spinal neuromodulation could represent a preliminary but potentially important systems-level strategy for aphasia recovery. Future studies should evaluate mechanistic pathways, optimal stimulation parameters, and clinical efficacy in randomized trials.