Experimental design. (A) Participants were randomly assigned to either the wake or sleep group. (B) In the first session, both groups developed and recorded 12 stories linking a location (e.g., a desert) with four objects. After recording the stories, they responded to three yes/no questions about their stories for each object (the right panel shows one example question). (C) Next, participants engaged in a position learning task. Each object was assigned a random on-screen position. Each block included objects from two contextually bound sets. First, participants were offered a chance to listen to the two stories. (Middle panel) After initiating the block, participants were asked in each trial to respond to an object-specific question. If they were correct, they attempted to place the object in its correct position. The block continued until all objects were learned to criterion. Feedback was provided in all trials. (D) At the end of the first session, participants were tested on their spatial memory. In each trial, participants also indicated their confidence level. An identical test was conducted in the second session.
