Comparing the attractor strength of intra- and interpersonal interlimb coordination using cross-recurrence analysis

Area of Science:

• Human movement science
• Neuroscience
• Complex systems

Background:

• Rhythmic interlimb coordination, both within and between individuals, is governed by coupled oscillator entrainment.
• Interpersonal coordination typically shows greater variability than intrapersonal coordination.
• This variability difference is hypothesized to stem from weaker interpersonal visual-motor coupling compared to intrapersonal neuromuscular coupling.

Purpose of the Study:

• To investigate the attractor dynamics underlying intra- and interpersonal rhythmic coordination.
• To test the assumption that interpersonal coupling results in weaker attractor dynamics.

Main Methods:

• Two experiments were conducted involving participants coordinating wrist-swung pendulums.
• Coordination was performed both intrapersonally (within-person) and interpersonally (between-person).
• Cross-recurrence quantification analysis (CRQA) metrics, specifically percent recurrence and maxline, were used to assess noise and attractor strength.

Main Results:

• Attractor strength was significantly weaker during interpersonal coordination compared to intrapersonal coordination.
• The level of noise was found to be similar for both intra- and interpersonal coordination.
• These results support the hypothesis regarding differences in attractor dynamics.

Conclusions:

• The weaker attractor strength in interpersonal coordination explains the increased movement variability observed in such tasks.
• Neuromuscular coupling provides a stronger dynamic attractor than visual-motor coupling between individuals.
• Future research could explore interventions to enhance interpersonal coordination dynamics.