ABSTRACT
Humans routinely engage simultaneously in motor and cognitive tasks. A series of experiments showed that performing cognitive tasks shifted the attractors, i.e. the stable states, of the coordination. Participants performed simultaneous bimanual coordination and reaction time (RT) tasks. Employing additional methods to vary coordination stability may clarify the impact of rhythmic movement on cognitive task performance. The wrist pendulum paradigm is well suited for this purpose. In addition to manipulations of required phase relation, the paradigm allows for the introduction of other factors known to compromise coordination stability, namely, movement frequency and detuning, i.e. the difference in preferred frequency of two limbs engaged in coordinated movement. Analyses were performed on response times in the RT task, and standard deviation of relative phase and phase shift in the coordination task. Phase shift was computed as the difference between actual and required phase relations between limbs.
