Modality-Specific Effect of Cueing on Inter-Manual Coordination in Bimanual Force Control Tasks with Accentuated- or Attenuated-Force Production.

Little is known about how perceptual modality affects the inter-manual coordination in bimanual force control tasks with accentuated- or attenuated-force production. This study examined the effects of relative phase patterns on the inter-manual coordination in a bimanual force control task with visual/vibrotactile cues. In the proposed force control task, both index fingers were required to simultaneously produce congruent accentuated- or attenuated-force pulses in the in-phase pattern, and produce incongruent ones in the anti-phase pattern. According to visual or vibrotactile cues, participants were prompted to quickly perform the bimanual force control task by pressing with their index fingers on force sensors from the same background force level. The inter-manual coordination performance was indexed by the delayed reaction time and timing difference of the index fingers. Results demonstrated that the advantage of the inter-manual coordination with vibrotactile cues in the in-phase patterns was significant over the anti-phase patterns. The inter-manual coordination of the index fingers could differentiate the in-phase patterns from the anti-phase patterns in the vibrotactile modality while the visual modality showed shorter delayed reaction time and less timing difference of the index fingers in the proposed force control task. Consequently, these findings suggested that the modality-specific effect of cueing on the advantage of the inter-manual coordination existed in the bimanual force control task with accentuated- or attenuated-force production using both index fingers simultaneously. This study would be referential for designing interactive applications leveraging inter-manual spatial coordination for in-phase and anti-phase patterns during bimanual synchronized force production.