Proceedings of the Annual Meeting of the Cognitive Science Society

We trust that the uncertainty regarding the outcome of a cointoss makes it a fair procedure for making a decision. Smalldifferences in the force used to toss a coin should not affect thisuncertainty. However, the voluntary movement involved intossing a coin is subject to motivational influences arising fromthe anticipation of the value of the outcome of the toss.Presented here are measurements of hand velocities duringcoin tossing when the outcomes entail monetary gains andlosses. Finger position measurements show that hand velocitiesare proportional to the amount of money at stake. Coin tossmovements are faster and larger for higher stakes than forsmaller monetary stakes.