Experimental design.

<p>(A) Trial sequence for the reward task on day 1. Words were repeatedly presented to ensure familiarization and reward learning. Each word indicated whether subjects could win money for a correct response in the letter case discrimination task. In rewarded trials, subjects received win feedback (image of gold coins) for correct responses and no-win feedback (grey-scale, scrambled image) for incorrect responses. Neutral trials were always followed by no-win feedback. (B) Trial sequence for the future imagery task on day 2. A text instruction indicated the task to be performed (“imagine an event” or “find two words”). In imagery trials, participants closed their eyes after processing the instruction and cue word, constructed a future event associated with the cue word, then pressed a button and continued to imagine additional details for the event. An audio signal indicated the end of the imagery period. Subjects opened their eyes and provided self-paced ratings of the imagined event on five scales: difficulty, vividness, coherence, valence, and similarity to an existing memory.