Effect of Short-Term Exposure to Supplemental Vibrotactile Kinesthetic Feedback on Goal-Directed Movements after Stroke: A Proof of Concept Case Series

Abstract

Many survivors of stroke have persistent somatosensory deficits on the contralesional side of their body. Non-invasive supplemental feedback of limb movement could enhance the accuracy and efficiency of actions involving the upper extremity, potentially improving quality of life after stroke. In this proof-of-concept study, we evaluated the feasibility and the immediate effects of providing supplemental kinesthetic feedback to stroke survivors, performing goal-directed actions with the contralesional arm. Three survivors of stroke in the chronic stage of recovery participated in experimental sessions wherein they performed reaching and stabilization tasks with the contralesional arm under different combinations of visual and vibrotactile feedback, which was induced on the ipsilesional arm. Movement kinematics were encoded by a vibrotactile feedback interface in two ways: state feedback—an optimal combination of hand position and velocity; and error feedback—the difference between the actual hand position and its instantaneous target. In each session we evaluated the feedback encoding scheme’s immediate objective utility for improving motor performance as well as its perceived usefulness. All three participants improved their stabilization performance using at least one of the feedback encoding schemes within just one experimental session. Two of the participants also improved reaching performance with one or the other of the encoding schemes. Although the observed beneficial effects were modest in each participant, these preliminary findings show that supplemental vibrotactile kinesthetic feedback can be readily interpreted and exploited to improve reaching and object stabilizing actions performed with the contralesional arm after stroke. These short-term training results motivate a longer multisession training study using personalized vibrotactile feedback as a means to improve the accuracy and efficacy of contralesional arm actions after stroke.

Vibrotactile Perception for Sensorimotor Augmentation: Perceptual Discrimination of Vibrotactile Stimuli Induced by Low-Cost Eccentric Rotating Mass Motors at Different Body Locations in Young, Middle-Aged, and Older Adults

“…Although the current study did not ask participants to use VTF stimuli to enhance performance of movement tasks as in our prior studies [cf., (10,18,19,24,32)], our results have identified several locations where VTF could reasonably be applied for sensory augmentation or substitution in the future. To the extent that perceptual acuity is required to successfully integrate continuous and graded-intensity vibrotactile feedback of kinesthetic information into the ongoing control of movement (18,19), the current results support the idea that regardless of age, people may be able to discriminate stimuli provided by vibrotactile sensory augmentation technologies, and potentially use them to mitigate persistent proprioceptive deficits after neuromotor injury [cf., (10,25)].…”

“…This study seeks to address that knowledge gap. This translational study contributes to a line of research that uses low-cost devices to provide vibrotactile feedback as a practical method of sensory augmentation for people with brain injuries leading to the loss of proprioceptive kinesthesia arising from mechanoreceptors in certain parts of the body [cf., (10)].…”

Extended practice improves the accuracy and efficiency of goal-directed reaching guided by supplemental kinesthetic vibrotactile feedback

“…Potential applications include mitigation of somatosensory impairments after stroke and enhancement of movement precision in the manual control of surgical robotics. Prior studies have shown that providing supplemental kinesthetic feedback during reaching and stabilizing movements of the arm can yield measurable improvements in accuracy and efficiency of those actions after less than 1 hour of practice in healthy individuals and in survivors of stroke (Tzorakoleftherakis et al 2015; Krueger et al 2017; Shah et al 2018; Risi et al 2019; Ballardini et al 2021). Motivated by classical descriptions of skill acquisition, we tested the hypothesis that extended practice on VTF-guided reaching would yield performance improvements that accrue in a manner increasingly resistant to dual-task interference (Fitts and Posner 1967).…”

“…While others have also proposed vibrotactile sensory interfaces to train body motions by providing feedback of spatial orientation or by stimulating the moving limb in response to limb configuration, few have attempted to mitigate the effects of somatosensory impairment or loss on the control of contralesional arm and hand movements after neuromotor injury errors (Lieberman and Breazeal 2007; Kapur et al 2009; Weber et al 2011; Bark et al 2015; König et al 2016). Those that have attempted this were largely technology demonstrations or feasibility case studies (De Santis et al 2014; Afzal et al 2015; Hussain et al 2015; Elangovan et al 2019; Ballardini et al 2021). None have examined the extent to which extended practice with such technology can facilitate learning of the novel sensorimotor relationships needed to establish novel closed-loop feedback control of a moving limb [but see König et al (2016) for a training study of sensory augmentation in the context of spatial navigation].…”

“…König et al (2016)]. Preliminary studies have demonstrated that within minutes of initial exposure to a novel sensory interface, neurologically intact individuals can rapidly learn to use supplemental feedback of limb configuration and movement to improve the accuracy of reaching actions performed without visual guidance and some survivors of stroke (Tzorakoleftherakis et al 2015(Tzorakoleftherakis et al , 2016Krueger et al 2017;Risi et al 2019;Ballardini et al 2021).…”