Effects of encoding the perceptual features of pictures on memory.

Four experiments investigated whether manipulations of type of encoding affects the likelihood of remembering pictures' visual details and their names. Using an incidental learning procedures, subjects were led to make judgments about pictures' colors, spatial orientations, or appropriateness in a scene. The results indicate that the nature of the memory test influences the effectiveness of different encoding conditions. Recall and recognition of pictures' names were best after subjects judged scene encodings, second best after they judged orientation, and poorest after they judged color. However, the results for the recognition of pictures' visual details were quite different. Analyses of d' suggested that type of encoding task had no effect on memory for visual details, whereas analysis of Pr (hit rate minus false-alarm rate) suggested that memory for visual details was impaired by conceptual encoding (judging the appropriateness of a picture in a scene). The results of one experiment demonstrated that these findings were not produced by variation in distinctiveness of the encoding questions. This pattern of findings implies that conceptual encoding facilitates retention of the names of the pictures at the cost of some loss in the ability to retain specific visual details.