Scenario Screen: A Dynamic and Context Dependent P300 Stimulator Screen Aimed at Wheelchair Navigation Control

Abstract

P300 spellers have been widely modified to implement nonspelling tasks. In this work, we propose a “scenario” stimulation screen that is a P300 speller variation to command a wheelchair. Our approach utilized a stimulation screen with an image background (scenario snapshot for a wheelchair) and stimulation markers arranged asymmetrically over relevant landmarks, such as suitable paths, doors, windows, and wall signs. Other scenario stimulation screen features were green/blue stimulation marker color scheme, variable Interstimulus Interval, single marker stimulus mode, and optimized stimulus sequence generator. Eighteen able-bodied subjects participated in the experiment; 78% had no experience in BCI usage. A waveform feature analysis and a Mann–Whitney U test performed over the pairs of target and nontarget coherent averages confirmed that 94% of the subjects elicit P300 (p < .005) on this modified stimulator. Least Absolute Shrinkage and Selection Operator optimization and Linear Discriminant Analysis were utilized for the automatic detection of P300. For evaluation with unseen data, target detection was computed (median sensitivity = 1.00 (0.78–1.00)), together with nontarget discrimination (median specificity = 1.00 (0.98–1.00)). The scenario screen adequately elicits P300 and seems suitable for commanding a wheelchair even when users have no previous experience on the BCI spelling task.

Brain-Controlled Wheelchair Review: From Wet Electrode to Dry Electrode, From Single Modal to Hybrid Modal, From Synchronous to Asynchronous

“…The P300 BCI-based motion path guidance strategy enabled the wheelchair to safely and effectively navigate in an indoor environment without complex sensors or sensor processing, circumventing the problem caused by the low information rate of the EEG signal [11,40,126]. A "scenario" stimulation screen optimised the motion guidance strategy [168]. However, in the path guidance strategy, the user's control right will be deprived after selecting the target.…”

30+ years of P300 brain–computer interfaces

“…The “Aware Chair” was designed to use P300s and other signals for wheelchair control and other goals (Moore, 2003). Several reports have described improvements to P300 BCI wheelchair control, including tactile P300 BCIs, hybrid BCIs, methods to reduce potentially hazardous wheelchair functions (such as “move forward” as opposed to “sound horn”), and more flexible options for BCI users (Iturrate, Antelis, Kübler, & Minguez, 2009; Jin, Allison, et al, 2014; Kaufmann et al, 2014; Piña‐Ramirez, Valdes‐Cristerna, & Yanez‐Suarez, 2018; Rebsamen et al, 2006; Yu et al, 2017). However, as with other robotic devices, P300 BCIs for wheelchair control need further work before they can be practical, safe systems without expert support and supervision.…”

Importance of Graphical User Interface in the design of P300 based Brain–Computer Interface systems

“…respectively. It is anticipated that in the future, possible integration of the design into a wheelchair could enable disabled/elderly users to control and utilise the system both for short (indoor), as well as long (outdoor), navigation -a protocol that has been well documented in the literature [31,32,33,34].…”