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In two experiments simultaneous color constancy was measured using simulations of illuminated surfaces presented on a CRT monitor. Subjects saw two identical Mondrians side-by-side: one Mondrian rendered under a standard illuminant, the other rendered under one of several test illuminants. The matching field was adjusted under the test illuminant so that it (a) had the same hue, saturation, and brightness (appearance match) or (b) looked as if it were cut from the same piece of paper (surface match) as a test surface under the standard illuminant. Matches were set for three different surface collections. The surface matches showed a much higher level of constancy than the appearance matches. The adjustment in the surface matches was nearly complete in the L and M cone data, and deviations from perfect constancy were mainly due to failures in the adjustment of the S cone signals. Besides this difference in amount of adjustment, the appearance and surface matches showed two major similarities. First, both types of matches were well described by simple parametric models. In particular, a model based on the notion of von Kries adjustment provided a good, although not perfect, description of the data. Second, for both types of matches the illuminant adjustment was largely independent of the surface collection in the image. The two types of matches thus differed only quantitatively, there was no qualitative difference between them.

Using DRM lists (Roediger & McDermott, 1995) in two experiments, we compared the effects of retrieval practice on a subset of the items and of the presentation of those items as retrieval cues at test on recall of the lists' critical items. In Experiment 1, the critical items were part of the studied lists, thus addressing these items' veridical recall; in Experiment 2, they were not studied, thus addressing these items' false recall. Three major results emerged. First, retrieval practice and part-list cuing reduced both veridical and false recall. Second, the two manipulations induced an integration effect in veridical recall, with substantial forgetting in lists with low false recall levels and no forgetting in lists with high false recall levels. Third, retrieval practice and part-list cuing created the same effects on recall, qualitativelyand quantitatively.These results suggest that the detrimental effects of retrieval practice and part-list cuing were mediated by similar mechanisms. They are consistent with the view that not only retrieval-induced forgetting, but also part-list cuing is caused by inhibitory processes.