Seeing Circles and Drawing Ellipses: When Sound Biases Reproduction of Visual Motion

Abstract

The perception and production of biological movements is characterized by the 1/3 power law, a relation linking the curvature and the velocity of an intended action. In particular, motions are perceived and reproduced distorted when their kinematics deviate from this biological law. Whereas most studies dealing with this perceptual-motor relation focused on visual or kinaesthetic modalities in a unimodal context, in this paper we show that auditory dynamics strikingly biases visuomotor processes. Biologically consistent or inconsistent circular visual motions were used in combination with circular or elliptical auditory motions. Auditory motions were synthesized friction sounds mimicking those produced by the friction of the pen on a paper when someone is drawing. Sounds were presented diotically and the auditory motion velocity was evoked through the friction sound timbre variations without any spatial cues. Remarkably, when subjects were asked to reproduce circular visual motion while listening to sounds that evoked elliptical kinematics without seeing their hand, they drew elliptical shapes. Moreover, distortion induced by inconsistent elliptical kinematics in both visual and auditory modalities added up linearly. These results bring to light the substantial role of auditory dynamics in the visuo-motor coupling in a multisensory context.

Modulation of ellipses drawing by sonification

“…The strong link between the modulation of the endpoint speed and the perceived shape was also demonstrated by experimental alterations of speed feedback (presented either by sounds (Thoret et al 2016) or visual point light displays (Viviani and Stucchi 1989;Viviani and Stucchi 1992) which biased visual perception of elliptical shapes. Conversely, the present study confirmed that the instruction to maintain a constant movement-sound relationship induces the stability of the drawing movement shape.…”

“…To that purpose, we chose an ecologically valid mapping based on the metaphor of friction sounds (e.g. chalk on a blackboard) inspired by the work of Kronland-Martinet's team who demonstrated that replaying friction sounds (recorded or synthesized) can evoke the shape of the ellipse drawings (Thoret et al 2014) and induce a sensorimotor perceptive bias on the reproduction of visual motion (Thoret et al 2016). In the present study, the participants had to draw repetitively ellipses while maintaining a constant sonification pattern (i.e.…”

Improving the Pedal Force Effectiveness Using Real-Time Sonification

“…Sonification has already been shown to influence user movement execution. For instance, Thoret et al [14] asked participants to draw a circle without being able to see their hands while a sound evoking an elliptical movement was played. The participants drew elliptical shapes, demonstrating that sound used in real-time could affect the movement.…”

Audio Feedback Associated With Body Movement Enhances Audio and Somatosensory Spatial Representation

“…Similarly, when auditory feedback is provided as an error signal, it reduces endpoint error in healthy subjects by 17%–31% (Hocherman et al, 1988 ; Hocherman, 1993 ), improving the sense of body position. Moreover, it has been shown that real-time auditory feedback in the form of timbre variations (Thoret et al, 2016 ) or sonification (Danna et al, 2015 ) can substantially alter motor performance.…”