Non-invasive, Brain-controlled Functional Electrical Stimulation for Locomotion Rehabilitation in Individuals with Paraplegia

Abstract

Spinal cord injury (SCI) impairs the flow of sensory and motor signals between the brain and the areas of the body located below the lesion level. Here, we describe a neurorehabilitation setup combining several approaches that were shown to have a positive effect in patients with SCI: gait training by means of non-invasive, surface functional electrical stimulation (sFES) of the lower-limbs, proprioceptive and tactile feedback, balance control through overground walking and cue-based decoding of cortical motor commands using a brain-machine interface (BMI). The central component of this new approach was the development of a novel muscle stimulation paradigm for step generation using 16 sFES channels taking all sub-phases of physiological gait into account. We also developed a new BMI protocol to identify left and right leg motor imagery that was used to trigger an sFES-generated step movement. Our system was tested and validated with two patients with chronic paraplegia. These patients were able to walk safely with 65–70% body weight support, accumulating a total of 4,580 steps with this setup. We observed cardiovascular improvements and less dependency on walking assistance, but also partial neurological recovery in both patients, with substantial rates of motor improvement for one of them.

Intra- and Inter-subject Variability in EEG-Based Sensorimotor Brain Computer Interface: A Review

“…In stroke patients, post-rehabilitation electromyographic recordings showed increased activity in the paretic finger following BCI-driven rehabilitation using an orthosis, which exhibits improvement in neuromuscular coherence for movement control (Ramos-Murguialday et al, 2013). Furthermore, BCIdriven proprioceptive feedback-based and functional electrical stimulation-based rehabilitation strategies could reinforce motor control (Zhao et al, 2016;Darvishi et al, 2017;Selfslagh et al, 2019).…”

A Roadmap Towards Standards for Neurally Controlled End Effectors

“…SCI patients [51]- [55]. More recently, BMI controlled spinal cord stimulation that allows brain signals to bypass and electrically stimulate below the injury site have also been developed [56].…”

3D Printable Dry EEG Electrodes with Coiled-Spring Prongs

“…Human intent has been decoded using technology such as functional magnetic resonance imaging, magnetoencephalography, functional near-infrared spectroscopy, and electroencephalography (EEG). EEG signals from the scalp using wet electrodes are widely used in communication [ 4 , 5 , 6 ], rehabilitation [ 7 , 8 ] due to these electrodes cost-effectiveness and high temporal resolution. However, conductive gels and glues are required to attach wet electrodes to the scalp [ 9 ], and the impedance of such gels and glues worsens over time [ 10 ], which makes it difficult to obtain stable measurements over a long period of time.…”