  One of the main causes of long-term prosthetic abandonment is the lack of
ownership over the prosthesis, caused mainly by the absence of sensory
information regarding the lost limb. One strategy to overcome this problem is
to provide alternative feedback mechanisms to convey information respective to
the absent limb. To address this issue, we developed a Biofeedback system for
the rehabilitation of transfemoral amputees, controlled via electromyographic
activity from the leg muscles, that can provide real-time visual and/or
vibratory feedback for the user. In this study, we tested this device with
able-bodied individuals performing an adapted version of the clinical protocol.
Our idea was to test the effectiveness of combining vibratory and visual
feedbacks and how task difficulty affects overall performance. Our results show
no negative interference combining both feedback modalities, and that
performance peaked at the intermediate difficulty. These results provide
powerful insights of what can be expected with the population of amputee people
and will help in the final steps of protocol development. Our goal is to use
this biofeedback system to engage another sensory modality in the process of
spatial representation of a virtual leg, bypassing the lack of information
associated with the disruption of afferent pathways following amputation.
