Improving electrotactile communication with a multi-pad electrode under cognitive load

Fabricio A Jure; Erika G Spaich; Laura Petrini; Jovana Malešević; Miloš Kostić; Matija Štrbac; Strahinja Došen

doi:10.1111/aor.14700

Improving electrotactile communication with a multi-pad electrode under cognitive load

Artif Organs. 2023 Dec 27. doi: 10.1111/aor.14700. Online ahead of print.

Authors

Fabricio A Jure¹, Erika G Spaich¹, Laura Petrini², Jovana Malešević³, Miloš Kostić³, Matija Štrbac³, Strahinja Došen¹

Affiliations

¹ Neurorehabilitation Systems, Department of Health Science and Technology, Aalborg University, Aalborg, Denmark.
² Center for Neuroplasticity and Pain, Department of Health Science and Technology, Aalborg University, Aalborg, Denmark.
³ Tecnalia Serbia, Belgrade, Serbia.

PMID: 38149317
DOI: 10.1111/aor.14700

Abstract

Background: Electrotactile systems are compact interfaces that can be used to convey information through the skin by producing a range of haptic sensations. In many applications, however, the user needs to perceive and interpret haptic stimulation while being engaged in parallel activities. Developing methods that ensure reliable recognition of electrotactile messages despite additional cognitive load is, therefore, an important step for the practical application of electrotactile displays.

Methods: This study investigated if a simple strategy of repeating electrotactile messages can improve message identification during multitasking. Ten participants identified 36 spatiotemporal electrotactile messages delivered through a 3 × 2 pad-matrix electrode placed on the torso while performing a concomitant cognitive task in three conditions: the messages were presented once (No-REP), and each message was repeated three (REP3) and five (REP5) times. The main outcome measure was the success rate (SR) of message identification.

Results: During multitasking, in the No-REP condition, the SR (median (IQR)) dropped to 56.25% (22.62%), demonstrating that the cognitive task decreased performance. However, the SR significantly improved with message repetitions, reaching 72.92% (21.87%) and 81.25% (18.66%) in REP3 and REP5 conditions respectively, without a statistically significant difference between REP3 and REP5.

Conclusions: Multitasking affected the efficacy of haptic communication, but message repetition was shown to be an effective strategy for improving performance. Additionally, only three repetitions were enough, as an additional increase in the duration of message transmission (5 repetitions) did not lead to further improvement. This study is an important step toward delivering electrotactile communication that can cope with the demands of real-world applications.

Keywords: encoding schemes; haptics; matrix electrodes; sensory biofeedback; task-switching.

Grants and funding

Horizon 2020 Framework Programme