Proceedings of the Annual Meeting of the Cognitive Science Society

Many collaborative tasks require people to coordinate interdependent actions under time constraints, often without explicit communication. In such ad hoc settings, observing others' emerging intentions may help groups rapidly align their actions. While information cascades are often studied as sources of bias in individual decision-making, they may play a constructive role in coordination by facilitating fast convergence on shared plans. We investigated this possibility in a multi-agent coordination task in which teams of three repeatedly solved a time-constrained block-moving problem (N = 471). We manipulated whether players could observe others' intentions in real time or only observe the outcome of each round. Teams with real-time signaling were more likely to complete the task. Within rounds, early votes were frequently followed by teammates, and these actions typically advanced task progress along efficient paths. Together, these findings suggest that access to real-time intention signals supports efficient ad hoc coordination by reducing decision uncertainty and stabilizing shared action plans.