Relative phase dynamics in perturbed interlimb coordination: stability and stochasticity

Post, A. A.; Peper, C. E.; Daffertshofer, Andreas; Beek, Peter J.

doi:10.1007/s004220000177

Cited by 48 publications

(45 citation statements)

References 14 publications

(26 reference statements)

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“…After perturbation of a bimanual coordination pattern the original pattern is typically restored, reflecting the stability properties of bimanual coordination (cf. Post et al, 2000a;Post et al, 2000b;Scholz et al, 1987). In the present study, the bimanual pattern was perturbed by suddenly arresting and subsequently releasing one of the limbs (thereby inducing an abrupt change in relative phase).…”

Section: Experimental Manipulations and Predictionsmentioning

confidence: 77%

“…For the purpose of making comparisons across the three frequency conditions, the time series of / were resampled with respect to cycle duration (De Poel et al, in press; for related procedures, see Bardy, Oullier, Bootsma, & Stoffregen, 2002;Court et al, 2002) prior to the analysis of the return signal, using an anti-aliasing (low-pass) finite impulse response (FIR) filter with a 10-point Kaiser window (available in the Matlab Ò Signal Processing Toolbox). Subsequently, the return signal (i.e., the evolution of / after release of the perturbed arm) was analyzed using the procedure outlined by Post et al (2000b). In brief, the data were fitted from the point where / reached a value of 45°(i.e., / t=0 = 45°), using an exponential decay function that also accounted for damped oscillations in the return signal:…”

Section: Discussionmentioning

confidence: 99%

“…where p is the offset in /, q = / t=0 -p, k is the decay parameter, x osc indicates the oscillation frequency of /, and h osc denotes the phase of this oscillation (for illustrations and more details, we refer to Post et al, 2000b). Note that this procedure yields adequate estimations of k both in the presence and absence of oscillations in the return signal of /.…”

Section: Discussionmentioning

confidence: 99%

“…Court, Bennett, Williams, & Davids, 2002;De Poel et al, in press;Post, Peper, & Beek, 2000a;Post, Peper, Daffertshofer, & Beek, 2000b;Scholz, Kelso, & Schö ner, 1987). After perturbation of a bimanual coordination pattern the original pattern is typically restored, reflecting the stability properties of bimanual coordination (cf.…”

Section: Experimental Manipulations and Predictionsmentioning

confidence: 99%

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Laterally focused attention modulates asymmetric coupling in rhythmic interlimb coordination

Poel

Peper

Beek

2006

Psychological Research

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Peters (J Motor Behav 21:151-155, 1989; Interlimb coordination: neural, dynamical and cognitive constraints, Academic, Orlando, pp 595-615, 1994) suggested that expressions of handedness in bimanual coordination may be reflections of an inherent attentional bias. Indeed, previous results indicated that focusing attention on one of the limbs affected the relative phasing between the limbs in a manner comparable to the effects of hand dominance. The present study extended the comparison between the effects of attentional focus and handedness by testing their impact on the interactions between the limbs. Both lefthanded and right-handed participants performed rhythmic bimanual coordination tasks (in-phase and antiphase coordination), while directing attention to either limb. Using brief mechanical perturbations, the degree to which the limbs were influenced by each other was determined. The results revealed that the non-dominant limb was more strongly affected by the dominant limb than vice versa and that, in line with Peters' proposition, this handedness-related asymmetry in coupling strength was reduced when attention was focused on the non-dominant limb, thereby highlighting the potential relation between inherent (handednessrelated) asymmetries and voluntary attentional asymmetries. In contrast to previous findings, the (commonly observed) phase lead of the dominant limb was attenuated (rather than accrued) when attention was focused on this limb. This unexpected result was explained in terms of the observed attention-related difference in amplitude between the limbs.

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Section: Experimental Manipulations and Predictionsmentioning

confidence: 77%

Section: Discussionmentioning

confidence: 99%

Section: Discussionmentioning

confidence: 99%

Section: Experimental Manipulations and Predictionsmentioning

confidence: 99%

See 2 more Smart Citations

Laterally focused attention modulates asymmetric coupling in rhythmic interlimb coordination

Poel

Peper

Beek

2006

Psychological Research

Self Cite

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“…Another example of the usefulness of motor variability can be found in studies of interlimb coordination conducted from a dynamical systems perspective. In this context, variability has been incorporated as random fluctuations to account for phenomena like critical fluctuations and critical slowing down in the vicinity of phase transitions, that is, situations in which a system switches between stable states or attractors, e.g., switches from antiphase to in-phase coordination (Haken et al 1985;Kelso 1984;Post et al 2000;Schöner et al 1986). In relation to the attractor strength, the amount of random fluctuations competes with stability and, thus, determines the flexibility of the system.…”

Section: Introductionmentioning

confidence: 99%

Deterministic and stochastic features of rhythmic human movement

2005

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The dynamics of rhythmic movement has both deterministic and stochastic features. We advocate a recently established analysis method that allows for an unbiased identification of both types of system components. The deterministic components are revealed in terms of drift coefficients and vector fields, while the stochastic components are assessed in terms of diffusion coefficients and ellipse fields. The general principles of the procedure and its application are explained and illustrated using simulated data from known dynamical systems. Subsequently, we exemplify the method's merits in extracting deterministic and stochastic aspects of various instances of rhythmic movement, including tapping, wrist cycling and forearm oscillations. In particular, it is shown how the extracted numerical forms can be analysed to gain insight into the dependence of dynamical properties on experimental conditions.

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Bimanual coordination in Parkinson's disease: Deficits in movement frequency, amplitude, and pattern switching

et al. 2002

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Six patients with idiopathic Parkinson's disease (PD) and six age-matched controls participated in a variety of rhythmic bimanual coordination tasks. The main goal of the task was to perform inphase or antiphase patterns of pronation and supination of the forearms at a specified tempo, and to switch from one pattern to the other upon presentation of a visual cue. The availability of advance information was varied to examine whether deficits would emerge under choice versus pre-cue constraints. In pre-cue conditions, the subjects knew in advance which hand would be cued to initiate pattern change. In choice conditions, the cued hand was not known until the imperative stimulus was presented. Overall, the PD patients made movements with significantly lower frequencies and smaller amplitudes relative to controls. Patients exhibited spontaneous pattern switching from antiphase to inphase at significantly lower movement frequencies than controls. During intentional switching trials, the control group was significantly faster at initiating pattern change. PD and control groups differed in the time to initiate pattern switching to a greater extent under choice conditions, suggesting that patients used advance information to increase the speed of their response. The control group exhibited a preference for spontaneous switching and intentional switching through the subdominant hand. Patients exhibited a switching preference using the impaired limb (whether or not it was subdominant). The control group made more correct responses when the subdominant side was either pre-cued or presented in choice conditions. The patients maintained the subdominant/impaired side advantage under pre-cue conditions but not choice. In the maintenance of rhythmic movement, individuals with PD were able to use advance information in terms of both speed and accuracy.

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Relative phase dynamics in perturbed interlimb coordination: stability and stochasticity

Cited by 48 publications

References 14 publications

Laterally focused attention modulates asymmetric coupling in rhythmic interlimb coordination

Laterally focused attention modulates asymmetric coupling in rhythmic interlimb coordination

Deterministic and stochastic features of rhythmic human movement

Bimanual coordination in Parkinson's disease: Deficits in movement frequency, amplitude, and pattern switching

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