Improving Spinal Cord Injury Rehabilitation Interventions by Retraining the Brain With Stimulation: Applying Concepts From Stroke

The long-term objective of this study is to optimize the rehabilitative potential in spinal cord injury (SCI) by maximally harnessing the potential available for functional neural plasticity. SCI is an important cause of serious, long-term disability in young adults. This fact, further complicated by rising disability-related costs, makes SCI a significant economic and social burden. Upper limb dysfunction is one of the most prevalent and debilitating impairments. More than 75% of patients with quadriplegia (paralysis of all 4 limbs following spinal cord injury in neck and upper back) prioritize return of upper limb function over any other lost function. Alleviating deficits of the upper limb may represent a cost-effective stategy to reducing the burden of SCI.

Although various exercise programs and neuromuscular stimulation methods have been employed to mitigate functional impairments of the arm and hand, success of these modalities is still debated. Evidence for efficacy of rehabilitation is inconclusive as outcomes are variable, confounded by methodological issues, and have shown poor generalizability. It is now speculated that limited succcess of rehabilitation emerges from inability of current methods to adequately harness the potential for significant neuroplasticity available in SCI.

Even though the site of damage in SCI does not involve the brain, the neural networks in the brain that control movement of the arm and hand are markedly affected. These regions lose their territory that the investigators argue could hamper effects of upper limb therapy. The Investigators objective is to directly modulate adaptive plasticity in these regions of the brain to enhance function of the upper limb in iSCI. The Investigators central hypothesis is that noninvasive brain stimulation, called transcranial direct current stimulation (tDCS), when delivered concurrently with rehabilitation will generate synergistic functional advantage. Adaptive plasticty would be obeserved as changes in structure of pathways emerging from the brain and the individual's function.