Experimental timeline.

<p>(A) Sample match and no-match trials from the WM phase. A memory cue and probe were presented for 1000 ms each, separated by a 2000 ms delay. (B) Sample trials from the repetition phase. Four repetition blocks were performed, corresponding to the four experimental conditions (WM set with paired repetition; WM set with unpaired repetition; Primed set with paired repetition; Primed set with unpaired repetition). The WM set was composed of memory cue items from the no-match trials in the study phase, while the memory probe items from no-match trials formed the Primed set. During the paired repetition blocks, items from either the WM or Primed set were briefly presented as repeated pairs, separated by a 500 ms interstimulus interval. During the unpaired blocks, the two stimuli presented within each trial were different items but were drawn from within the same (WM or primed) set. Each item was presented twice over the course of the block. To ensure attention to the display, participants responded with a button press when the fixation cross changed colour. (C) Sample trial from the memory recognition test performed outside the scanner. Participants indicated whether the item was old (previously seen) or new. They then rated their confidence in that judgement on a scale from 1 (not at all confident) to 3 (very confident).