Figure 1.

Perceptual search and episodic memory search tasks. a, Trial structure in the perceptual search task. A sentence instructed subjects to search for a specific target (object or character) that could appear at any time in the upcoming 12 s video clip. Subjects searched for the target while fixating a central cross and pressed a button as soon as the target was detected. Search duration was varied (early, middle, late) by manipulating the time at which the target was presented. After display offset, a variable ITI was interposed before the onset of the next sentence. b, Trial structure in the episodic memory search task. Subjects read a sentence describing a specific detail of a previously encoded episode from a TV show. They then retrieved information from episodic memory to judge the accuracy (i.e., true, false) of the sentence, which they indicated by pressing one of two buttons. Subjects were given up to 15 s to provide the judgment on each trial. An example of early, middle, and late search trials are provided. After subjects' response, a variable ITI was interposed before the onset of the next sentence.