Figure 3.

Upper panel: Schematic diagram of design examining maintenance of item information across trials. Trial A immediately precedes Trial B. In the hiSim condition, the probe for Trial B (with value p^B) is very similar in perceptual space to the stimuli from Trial A (study stimuli and, with probe, $s_1^A$ and $s_2^A$, with probe, p^A). The horizontal axis represents the stimulus space, items closer to each other are more similar. In the loSim condition, p^B is different from $s_1^A,s_2^A$, and p^A. If item information were maintained from trial to trial, more false alarms (on Trial B) would be expected for the hiSim condition, as interference between the probe and stimuli from a previous trial should be greater in that condition than the loSim condition. Note that Trial B is the same in each case. p indicates the probe frequency, s₁ and s₂ indicate the frequencies of the first and second study stimuli. Within the hiSim condition, on some trials p^B matched a stimulus from Trial A (p^B ∈ A), while on other trials, p^B did not match any stimulus from Trial A (p^B ∉ A). The percentage of false alarm trials observed for each condition are shown in filled boxes. Lower panel: Box plot shows median (thick bar); middle 50% of data are encompassed by boxes. The whiskers include all data points that are not outliers. Circles represent outliers, defined as points >1.5× the inter- quartile range from the median. Note that more false alarms were made in the hiSim condition.