Social Psychology in the Task Organization of Dyadic 90° Rhythmic Coordination: The Coupling Is Not What You Might Expect

Herth, Zhu and Bingham (2021) investigated frequency scaling of a learned 90° bimanual rhythmic coordination in the context of both noninterference and correcting instructions. They found that performance of 90° coordination remained stable at high frequencies with correcting, but that performance deteriorated as frequency increased without correcting. The participants trained during learning both at performing bimanual and unimanual coordination and in both cases, they trained to the same criterion level of performance. Herth, Zhu and Bingham (submitted) then tested these same participants with frequency scaling of unimanual 90° coordination. They found in this case that the stability of performance was lost in the same way both with and without correcting. The question raised by this difference in results was whether the inability to maintain stable performance of unimanual coordination with correcting was due to the lack of kinesthetic/neural coupling or to the lack of bidirectional coupling present in bimanual coordination. To separate the two differences in coupling, frequency scaling of learned 90° coordination between two people (dyads) was tested in the current study because this was expected to isolate bidirectional coupling without the kinesthetic/neural coupling. Dyadic coordination is strictly visual. However, the results were identical to those found with unimanual coordination. The ability to correct did not yield stable performance at high frequency. An analysis was performed that showed that the coupling in the dyadic coordination was unidirectional contrary to the common expectation. Dyads were not allowed to communicate directly during learning and testing sessions, but they established the role of the coordinator and corrector vs who would just be steady state in organizing the task performance, nevertheless. Some dyads never achieved criterion performance even after over a dozen training sessions. Perchance they failed to achieve the requisite task organization. The results yielded an interesting problem in social psychology.