Movement-related sensory feedback mediates the learning of a new bimanual relative phase pattern

On the basis of findings emphasizing the role of perceptual consequences in movement coordination, the authors tested the hypothesis that the learning of a new bimanual relative phase pattern would involve the matching of the movement-related sensory consequences (rather than the motor outflow commands) to the to-be-learned pattern. Two groups of participants (n = 10 in each) practiced rhythmically moving their forearms with a phase difference of 30°. In 1 group, a difference in the arms' eigenfrequencies was imposed such that synchronous generation of the left and right motor commands resulted in the required relative phase (30°), yielding incongruence between the motor commands and their sensory consequences. In the other group, the experimenter imposed no eigenfrequency difference so that the sensory consequences were congruent with the motor commands. Throughout the practice period, performance of both groups was assessed repeatedly for the congruent situation (i.e., no eigenfrequency difference). On those criterion tests, both groups performed the required pattern equally well. The authors discuss that result, which corroborated the hypothesis, from a dynamical systems perspective

Abrupt vs. gradual destabilization at copying affects the subsequent evolution of graphic patterns accuracy at reproduction

Participants should trace graphic patterns with respect to a visual model (copying) and, after an interval of varying length (0, 10 and 20 s), reproduce the patterns from memory (reproduction). The 0°, 45°, 90°, 135° and 180° relative phase patterns were analyzed. At copying, the patterns were destabilized by manipulating movement frequency. The results revealed that absolute error and variability were higher when participants traced the patterns at a rapid rather than at a spontaneous movement frequency. Later, the effect of destabilization decayed resulting in accuracy improvement. After an abrupt change from rapid to spontaneous movement frequency at copying, the improvement in accuracy was manifested with the 0 s interval. After a gradual decrease in frequency, the improvement in accuracy appeared for the 10 and 20 s interval. The results indicate that the evolution of accuracy at reproduction was sensitive to how the destabilization was administered at copying

Spontaneous Covariations of Movement Parameters in 5- to 7-Year-Old Boys

International audienc

Abrupt vs. gradual destabilization at copying affects the subsequent evolution of graphic patterns accuracy at reproduction

Participants should trace graphic patterns with respect to a visual model (copying) and, after an interval of varying length (0, 10 and 20 s), reproduce the patterns from memory (reproduction). The 0°, 45°, 90°, 135° and 180° relative phase patterns were analyzed. At copying, the patterns were destabilized by manipulating movement frequency. The results revealed that absolute error and variability were higher when participants traced the patterns at a rapid rather than at a spontaneous movement frequency. Later, the effect of destabilization decayed resulting in accuracy improvement. After an abrupt change from rapid to spontaneous movement frequency at copying, the improvement in accuracy was manifested with the 0 s interval. After a gradual decrease in frequency, the improvement in accuracy appeared for the 10 and 20 s interval. The results indicate that the evolution of accuracy at reproduction was sensitive to how the destabilization was administered at copying

Chapter 5 Concepts and Methods for A Dynamical Approach to Behavioral Coordination and Change

International audienc