Pilot study for a Brain-Muscle-Computer Interface using the Extensor Pollicis Longus with preselected frequency bands

Abstract

We are developing a new class of Brain-Computer Interface that we call a Brain-Muscle-Computer Interface, in which surface electromyography (sEMG) recordings from a single muscle site are used to control the movement of a cursor. Previous work in our laboratory has established that subjects can learn to navigate a cursor to targets by manipulating the sEMG from a head muscle (the Auricularis Superior). Subjects achieved two-dimensional control of the cursor by simultaneously regulating the power in two frequency bands that were chosen to suit the individuals. The purposes of the current pilot study were to investigate (i) subjects' abilities to manipulate power in separate frequency bands in other muscles of the body and (ii) whether subjects can adapt to preselected frequency bands. We report pilot study data suggesting that subjects can learn to perform cursor-to-target tasks on a mobile phone by contracting the Extensor Pollicis Longus (a muscle located on the wrist) using frequency bands that are the same for every individual. After the completion of a short training protocol of less than 30 minutes, three subjects achieved 83%, 60% and 60% accuracies (with mean time-to-targets of 3.4 s, 1.4 s and 2.7 s respectively). All three subjects improved their performance, and two subjects decreased their time-to-targets following training. These results suggest that subjects may be able to use the Extensor Pollicis Longus to control the BMCI and adapt to preselected frequency bands. Further testing will more conclusively investigate these preliminary findings.

Pilot study on the use of audio feedback for sEMG-based brain-machine-body interface

“…The next step in our investigation is to examine how performance with audio feedback compares to that with standard visual performance in an otherwise identical paradigm. Our previous studies have used visual feedback, but with different protocols and hardware [1,2]. A unified study should be completed using the same hardware and same protocol, which must be carefully designed.…”

“…In previous experiments we have demonstrated that subjects can use the interface to perform cursor-to-target tasks with the aid of visual feedback of cursor position [1,2]. Here, we investigate if subjects can perform this task when feedback is presented as auditory, rather than visual.…”

“…We are developing a novel sEMG based Brain-Machine-Body Interface for the disabled, in which users continuously control a cursor on a screen in two-dimensions by manipulating the surface electromyography (sEMG) at one single muscle site [1,2]. In previous experiments we have demonstrated that subjects can use the interface to perform cursor-to-target tasks with the aid of visual feedback of cursor position [1,2].…”

Assistive grasping with an augmented reality user interface

“…A series of works (Joshi et al, 2011; Perez-Maldonado et al, 2010; Skavhaug et al, 2012, 2016) have shown that the input device can record two simultaneous channels from a single recording site. This is achieved by training the subject to modulate the activation of the muscles near the recording site in order to control the power voluntarily in two separate frequency bands.…”

Effects of muscle fatigue on the usability of a myoelectric human-computer interface

“…We employ a previously described novel myoelectric HCI, which requires subjects to manipulate the power spectrum in a single surface EMG (sEMG) signal through low-level dynamic muscle contractions (Perez-Maldonado et al, 2010;Vernon & Joshi, 2011, Skavhaug, Bobell, Vernon, & Joshi, 2012Lyons & Joshi, 2013;Skavhaug, Lyons, Nemchuk, Muroff, & Joshi, 2016). The ultimate purpose of the sEMGbased device is the translation to a practical user interface for people with paralysis.…”