The Effect of Cognitive Load on Electrotactile Communication via a Multi-pad Electrode

Enhancing the perception of the surrounding environment by conveying information through tactile stimulation can improve performance, especially when other senses are already overloaded (e.g., first responders). Delivering electrotactile messages using spatiotemporal patterns has been suggested as an efficient and reliable approach to transmitting information through the skin. However, the effectiveness of this approach depends on the user’s capability to recognize tactile messages in potentially challenging scenarios (e.g., rescue operations). Therefore, the present study evaluated the participants’ performance in identifying electrotactile messages while they performed a parallel cognitive task. Thirty-six electrotactile messages were delivered through a 3 × 2 pad-matrix at the lateral torso in the baseline and multitasking conditions. The task-switching paradigm was employed as the parallel task, introducing cognitive interference to the electrotactile message recognition. The assumption was that the simultaneous task would impair the identification performance, but that this impairment could be minimized by decreasing the speed at which the message was delivered. The results indeed showed that the identification success rates decreased from  ~83% in the baseline to ~61% during multitasking. Unexpectedly, the performance did not recover when the message duration was increased. Hence, modulating the message duration seems not to be an effective strategy to prevent lower performance while multitasking.