Directed forgetting has been studied by instructing Ss to forget either (a) an initial list or (b) individually selected words. Differential encoding was hypothesized to be responsible for wordmethod directed forgetting, and retrieval inhibition for list-method directed forgetting. In Experiments 1 and 2, directed forgetting was observed in recognition with the word method but not with the list method. Release from directed forgetting occurred in final recall after recognition but only with the list method. These results are interpreted in terms of a theoretical framework that integrates distinctive-relational processing theory with revised generation-recognition theory. In Experiments 1-3, predictions from that framework were generally well supported on implicit and explicit retention tests that provided the same stimulus conditions. Consistent with processing theory, list-method directed forgetting was absent on data-driven or conceptually driven implicit tests, and word-method directed forgetting was absent on data-driven implicit tests.

Recognition can suffer if the retrieval cues activate more than one trace (e.g., for Flower A and Flower A'). We found evidence for two retrieval processes by examining interference effects in forced-choice tests (e.g., "Did you see Flower A or Flower A"?). Experiment 1 provided evidence of a problem in discriminating between temporally and contextually similar traces that were formed in the study phase. A competitor (Flower A') interfered more if it was shown in the study phase rather than in the test phase. Experiments 2 and 3 found evidence for a blocking process in recognizing pairs of words (child-apple). A competitor interfered more if it was recent, shown at test rather than at study. This pattern occurred regardless of whether the competitor was similar to the target (child-orange) or dissimilar to it (child-truck). The importance of a particular retrieval process may depend on an item's representation as well as on the retrieval cues.

The results of three experiments suggest that a memory trace for an event is not altered by witnessing similar events\ but that postevents can interfere with its retrieval[ On an immediate recall test\ details from an original story "e[g[ wrench# were recalled less often if a subsequent story mentioned a {screwdriver| than if it did not[ The interference e}ect occurred if people were asked to recall details from both stories "tool ** **#\ but not if people were asked to recall primarily from the _rst story[ Thus\ the interference e}ect in immediate recall was averted if the target trace could be activated selectively "Experiments 0a and 0b#[ A more general interference e}ect was found after a day[ Fewer targets from the original story were recalled if the second story was presented just before the test than if both stories occurred a day earlier[ Thus\ the second story interfered with recall only if it emphasized contextual retrieval cues that did not match the trace for the targets "Experiment 1#[

In three experiments we compared posthypnotic amnesia (PHA) with directed forgetting (DF), evaluating subjects' hypnotic susceptibility, hypnotized or not. Experiment 1 suggested that the memory processes in PHA and DF were not the same. Low and high susceptibility subjects responded differently in the two contexts. Experiment 2 demonstrated a context effect for highly susceptible subjects: They showed the usual DF response outside hypnosis but not during hypnosis. Experiment 3 showed that high and low susceptibility subjects responded similarly to DF instructions outside hypnosis, eliminating the susceptibility as an important variable in the DF response. We concluded: (a) The interaction of context and susceptibility was the important determinant of unusual DF responses for high susceptibles, and (b) information processing concepts are too limited to explain PHA and perhaps DF. Theories that include interactions appear necessary for an accurate understanding of hypnotic phenomena and perhaps some phenomena usually focused on by cognitive psychology.

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