Conflicts between expected and actually performed behavior lead to verbal report of incidentally acquired sequential knowledge.

According to the Unexpected-Event Hypothesis (UEH) (Frensch, Haider, Rünger, Neugebauer, Voigt & Werg, 2002), conflicts between expected and actually performed behaviors trigger attribution processes and ultimately lead to the ability to verbally report an incidentally experienced sequential regularity. In two experiments, we manipulated the likelihood that a specific conflict, a premature response, occurred in a sequential version of the Number Reduction Task (NRT). Experiment 1 demonstrated that a longer RSI leads to a larger number of premature responses and to more verbal report than a shorter RSI. However, this effect of the RSI on verbal report was removed when participants were discouraged from emitting premature responses. Experiment 2 revealed that artificially inducing premature responses leads to an increase in verbal report, but only when premature responses are introduced late in training. Overall, the findings strongly support the assumptions of the UEH.