Effect of finger tracking combined with electrical stimulation on brain reorganization and hand function in subjects with stroke

Abstract

Synergism of rehabilitative interventions could maximize recovery following stroke. We examined whether the combination of peripherally initiated electrical stimulation of finger extensors and centrally operating finger tracking training could accentuate brain reorganization and its relationship to recovery, beyond the effects of either treatment alone. Twenty subjects with stroke were randomly assigned to an electrical stimulation (ES), tracking training (TR) or combination (CM) group. Each group was trained for ten 1-h sessions over 2-3 weeks. Pretest and posttest measurements consisted of the Box and Block and Jebsen Taylor tests of manual dexterity and a finger tracking test that was performed during functional magnetic resonance imaging (fMRI). fMRI variables included laterality index and BOLD signal intensity of primary motor (M1), primary sensory (S1), sensorimotor (SMC) and premotor (PMC) cortices as well as, supplementary motor area (SMA). ES and CM groups improved on dexterity, whereas the TR group did not. Improvement in the CM group was not greater than the other two groups. Subjects who had an intact M1 showed greater functional improvement than those who had direct involvement of M1. fMRI analysis did not yield significant changes from pretest to posttest. In the CM group only, functional improvement was positively correlated with laterality index change in M1, S1, SMC and PMC, indicating greater ipsilesional control and was negatively correlated with BOLD Signal Intensity change in ipsilesional S1 and SMA, indicating neurophysiological trimming of irrelevant neurons. The correlational results suggest that the combined intervention may be more influential on brain reorganization than either treatment alone but a larger sample size, longer duration of training, or a restricted inclusion of stroke location and volume may be needed to demonstrate a difference in efficacy for producing behavioral changes.

Effects of Integrated Volitional Control Electrical Stimulation (IVES) on Upper Extremity Function in Chronic Stroke

“…Previous studies 3,5,7,8 have demonstrated that electrical stimulation combined with volitional efforts or additional therapy is more effective than electrical stimulation alone in the recovery process. Bhatt et al 21 showed that combined intervention may have a more beneficial influence on brain reorganization than either treatment alone. Increased motor cortical excitability facilitates greater voluntary activation of its neuronal networks, 22 which could lead to improved functions.…”

Rethinking Stimulation of the Brain in Stroke Rehabilitation

“…Vicarious recruitment of alternate ipsilesional (Dancause and others 2006; Frost and others 2003; Plow [nee (Bhatt)] and others 2007; Seitz and others 1998; Ward and others 2007; Weiller and others 1992) and contralesional (Bestmann and others 2010; Johansen-Berg and others 2002; Lotze and others 2012) motor regions and changes in their connectivity with ipsilesional PMA or with M1 can be studied with resting state fMRI. Based on correlated cortical activity in resting state, resting state fMRI defines functional connectivity between regions.…”

Exploring the effects of synchronous pharyngeal electrical stimulation with swallowing carbonated water on cortical excitability in the human pharyngeal motor system

“…By contrast, the combination of a motor task (swallowing) with functional electrical stimulation (PES) was ineffective. Earlier research regarding hand and leg rehabilitation using motor training with sensory stimulation suggested that that this type of combined stimuli can induce larger changes in excitability and/or neuroplasticity in motor cortex [39][40][41] , whereas tongue protrusion motor training, which alone produces measured neuroplasticity and successful performance, was less effective on motor cortex with nociceptive sensory stimulation. 42 These may be due to the differences in the neural systems between spinal and cranial nerves or in the type of experimental noxious stimulus.…”