Effect of task-related continuous auditory feedback during learning of tracking motion exercises

Abstract

BackgroundThis paper presents the results of a set of experiments in which we used continuous auditory feedback to augment motor training exercises. This feedback modality is mostly underexploited in current robotic rehabilitation systems, which usually implement only very basic auditory interfaces. Our hypothesis is that properly designed continuous auditory feedback could be used to represent temporal and spatial information that could in turn, improve performance and motor learning.MethodsWe implemented three different experiments on healthy subjects, who were asked to track a target on a screen by moving an input device (controller) with their hand. Different visual and auditory feedback modalities were envisaged. The first experiment investigated whether continuous task-related auditory feedback can help improve performance to a greater extent than error-related audio feedback, or visual feedback alone. In the second experiment we used sensory substitution to compare different types of auditory feedback with equivalent visual feedback, in order to find out whether mapping the same information on a different sensory channel (the visual channel) yielded comparable effects with those gained in the first experiment. The final experiment applied a continuously changing visuomotor transformation between the controller and the screen and mapped kinematic information, computed in either coordinate system (controller or video), to the audio channel, in order to investigate which information was more relevant to the user.ResultsTask-related audio feedback significantly improved performance with respect to visual feedback alone, whilst error-related feedback did not. Secondly, performance in audio tasks was significantly better with respect to the equivalent sensory-substituted visual tasks. Finally, with respect to visual feedback alone, video-task-related sound feedback decreased the tracking error during the learning of a novel visuomotor perturbation, whereas controller-task-related sound feedback did not. This result was particularly interesting, as the subjects relied more on auditory augmentation of the visualized target motion (which was altered with respect to arm motion by the visuomotor perturbation), rather than on sound feedback provided in the controller space, i.e., information directly related to the effective target motion of their arm.ConclusionsOur results indicate that auditory augmentation of visual feedback can be beneficial during the execution of upper limb movement exercises. In particular, we found that continuous task-related information provided through sound, in addition to visual feedback can improve not only performance but also the learning of a novel visuomotor perturbation. However, error-related information provided through sound did not improve performance and negatively affected learning in the presence of the visuomotor perturbation.

Investigating three types of continuous auditory feedback in visuo-manual tracking

“…This supports the idea that the benefits of the different sound feedback tested are not due other uncontrolled effects (like focus of attention for instance), but to the mapping between motion and sound in the auditory feedback. The fact that Target as well as Error auditory feedback significantly improved performance differs from the observations by Rosati et al (Rosati et al, 2012), where an error sonification did not prove to help for the tracking task. Our results also pointed out that the pointer-related (user-related) group improved its performance with repetition, contrary to the two other groups.…”

“…Rosati et al reported studies on unidimensional tracking with a joystick, comparing the sonification of the target velocity and the tracking error (Rosati et al, 2012). They found that auditory feedback based on task parameters (features of the target or the setup) improved performance during an unpredictable task.…”

“…Rosenkranz and Rothwell (Rosenkranz and Rothwell, 2012) showed that integration and modulation of proprioceptive input induced a positive effect on motor learning. Wong et al (Wong et al, 2012) showed that a proprioceptive training could reduce position error and increase speed, leading to a larger learning in arm movement.…”

Effects of Complementary Auditory Feedback in Robot-Assisted Lower Extremity Motor Adaptation

“…Similarly, related experiments performed on healthy subjects revealed how auditory feedback can also be effective in reducing tracking error. In particular, continuous task-related information provided through sound in addition to visual feedback can improve not only performance but also learning of a novel visuomotor perturbation [42], [43]. Similar forms of auditory feedback can more or less be applied to gait rehabilitation, and this is indeed what this papers deals with.…”

Design and Construction of a Bilateral Haptic System for the Remote Assessment of the Stiffness and Range of Motion of the Hand

“…satisfies Equation (10). However, in the P-F-type two-channel architecture, E 3 = C 2 = 0, so the optimal law for transparency reduces to:…”