Visual perception of the relative phasing of human limb movements

Abstract

Studies of bimanual coordination have found that only two stable relative phases (0°and 180°) are produced when a participant rhythmically moves two joints in different limbs at the same frequency. Increasing the frequency of oscillation causes an increase in relative phase variability in both of these phase modes. However, relative phasing at 180°is more variable than relative phasing at 0°, and when the frequency of oscillation reaches a critical frequency, a transition to 0°occurs. These results have been replicated when 2 people have coordinated their respective limb movements using vision. This inspired us to investigate the visual perception of relative phase. In Experiment 1, recordings of human interlimb oscillations exhibiting different frequencies, mean relative phases, and different amounts of phase variability were used to generate computer displays of spheres oscillating either side to side in a frontoparallel plane or in depth. Participants judged the stability of relative phase. Judgments covaried with phase variability only when the mean phase was 0°or 180°. Otherwise, judgments covaried with mean relative phase, even after extensive instruction and demonstration. In Experiment 2, mean relative phase and phase variability were manipulated independently via simulations, and participants were trained to perceive phase variability in testing sessions in which mean phase was held constant. The results of Experiment 1 were replicated. The HKB model was fitted to mean judgment standard deviations.Phase refers to the proportion of the cycle traveled at a given time in a rhythmic motion. If the motion is represented as a trajectory on the phase plane (i.e., a plot ofvelocity vs. position), then the phase is the angular coordinate of the motion (measured in degrees or radians). The relative phase of two motions (e.g., the swinging of two legs) is the difference ofthe two phases. A number ofstudies have shown that, when a person oscillates two equivalent limbs at a common frequency and each about a single joint, then one of only two stable relative phase relations is exhibited, either 0°or 180°relative phase (Kelso. 1984(Kelso. , 1995Kelso, Schoner, Scholz, & Haken, 1987;Schoner & Kelso, 1988;Tuller & Kelso, 1989;Yaminishi, Kawato, & Suzuki, 1979, 1980. For instance, Tuller and Kelso (1989) used two metronomes Portions of this work were presented at the annual meeting ofthe Psychonomic Society. November 1996 (Bingham, Schmidt, & Zaal, 1996;Zaal, Bingham, & Schmidt, 1996). The authors wish to acknowledge the assistance of Michael Stevens in the data collection of Experiment I, Michael Stassen in programming the simulations of Experiment 2, and James Craig, Tim Lee, and an anonymous reviewer for valuable suggestions about methodology and analysis. Correspondence to should be addressed to G. P. Bingham, Department of Psychology, Indiana University, Bloomington, IN 47405 (e-mail: gbingham@indiana.edu).to help participants to try to oscillate their left and right index fingers at relative phases other than 0°an...

The integration of temporally shifted visual feedback in a synchronization task: The role of perceptual stability in a visuo-proprioceptive conflict situation

“…The performance in the in-phase synchronization mode corroborated the findings in the literature (Bingham et al, 1999;Bogaerts et al, 2003;Buekers et al, 2000;Langenberg et al, 1998;Roerdink, Peper, & Beek, 2005;Ryu & Buchanan, 2009;Swinnen, et al, 1998;Wilson, Collins, & Bingham, 2005a, 2005b. The spatial accuracy of the arm movements was significantly lower in the 50% feedback condition in which the spatial incompatibility (i.e., perception of the arm in a position that is incompatible with the proprioceptive information of the muscle afferents) between the target signal and the temporally shifted visual feedback of the actual arm movement was maximal Poulton, 1974).…”

“…These studies highlighted the role of perception in the rhythmic movement coordination since the coupling was visually mediated by the ability to detect the information used to couple and coordinate the oscillating limbs (Wilson, Collins, & Bingham, 2005a, 2005b. Moreover, the stability of the perception of two oscillating visual signals was found to vary as an asymmetric U-function of mean relative phase (i.e., dependent on the directional compatibility between the oscillating signals) (Bingham, Schmidt, & Zaal, 1999;Bingham, Zaal, Shull, & Collins, 2001;Zaal, Bingham, & Schmidt, 2000). In fact, non-0° phase relations between the two oscillating visual signal were judged to be intrinsically more variable than 0°, maximally so at 90°, with 180° phase relation judged to be intermediate between these performance extremes at 0° and ACCEPTED MANUSCRIPT Synchronization 4 90°.…”

Proprioceptive Perception of Phase Variability.

“…Bingham and Collins (2002) replicated the frequency results using frequencies ranging from 1Hz to 3Hz, and showed that the variability in judgments of both mean relative phase and of phase variability was also an inverted U-shaped function of mean relative phase. Bingham, Schmidt, and Zaal (1999) replicated these results by using oscillators driven by actual human movement. Zaal, Bingham, and Schmidt (2000) used dots oscillating in both the fronto-parallel plane and in depth, and showed that the levels of phase variability were discriminated best at 0°, then 180°, and not at all at 90°.…”

Transfer of learning between unimanual and bimanual rhythmic movement coordination: transfer is a function of the task dynamic

“…The model predicted results both from movement studies (e.g. Kay, Kelso, Saltzman and Schöner 1987;Kay, Saltzman and Kelso 1991;Kelso 1984;Schmidt, Carello and Turvey 1990) and from perceptual judgment studies that had investigated both vision (Bingham, Schmidt and Zaal 1999;Bingham, Schmidt, Shull and Collins 2001;Collins and Bingham 2001;Zaal, Bingham and Schmidt 2000) and proprioception (Wilson, Craig and Bingham 2003). It is this model that motivated the current study because it generates predictions about how learning one version of this task should generalise to another version.…”