The active learning task.

<p>A) Time course of events in a single active learning trial. Subjects were presented a symbol pair and had to choose one of the symbols within 3500 ms via button press. Shortly after indication of the choice, positive (“correct”, grey circles appeared in green) or negative (“incorrect”, grey circles appeared in red) feedback was given. Subjects were instructed to pay attention to stimuli and associated outcomes in order to maximise the number of correct choices in all phases of the experiment. B) Time course of events in a single test or transfer phase trial. Trials in the test or transfer phase were identical to active learning trials except that no feedback was given. C) Learning and test phases alternated until subjects showed evidence of learning stimulus-outcome contingencies (maximally five learning and test phases were conducted; see Active Learning from Feedback for details). The task ended with the transfer phase (see Active Learning from Feedback for details).