We report a new paradigm for studying false memories implanted by social influence, a process we ... more We report a new paradigm for studying false memories implanted by social influence, a process we call the social contagion of memory. A subject and confederate together saw six common household scenes (e.g., a kitchen) containing many objects, for either 15 or 60 sec. During a collaborative recall test, the 2 subjects each recalled six items from the scenes, but the confederate occasionally made mistakes by reporting items not from the scene. Some intrusions were highly consistent with the scene schema (e.g., a toaster) while others were less so (e.g., oven mitts). After a brief delay, the individual subject tried to recall as many items as possible from the six scenes. Recall of the erroneous items suggested by the confederate was greater than in a control condition (with no suggestion). Further, this social contagion effect was greater when the scenes were presented for less time (15 sec) and when the intruded item was more schema consistent (e.g., the toaster). As with other forms of social influence, false memories are contagious; one person's memory can be infected by another person's errors.
Experiments 1-3 were based on a master's thesis by M.L.M. conducted under supervision of H.L.R. W... more Experiments 1-3 were based on a master's thesis by M.L.M. conducted under supervision of H.L.R. We thank David A. Balota and Alan J. Lambert, the other members of the committee, for their advice and comment. We also thank Four experiments examined social influence on the development of false memories. We employed the social contagion paradigm: A subject and a confederate see scenes and then later take turns recalling items from the scenes, with the confederate erroneously reporting some items that were not present in the scenes; on a final test, the subject reports these suggested items when instructed to recall only items from the scenes.The first two experiments showed that the social contagion effect persisted when subjects were explicitly warned about the possibility that confederates' responses might induce false memories and when they were tested via source-monitoring tests that explicitly gave the choice of attributing suggested items to the other person. Levels of false recall and recognition increased with the number of times the misleading information was suggested (Experiment 3), and subjects were more likely to incorporate the erroneous responses of an actual confederate on a recognition/source test as compared with those of a simulated confederate (Experiment 4). Collectively, the data support the claim that false memories may be transmitted between people and reveal critical factors that modulate the social contagion of memories.
In two experiments, we examined age differences in collaborative inhibition (reduced recall in pa... more In two experiments, we examined age differences in collaborative inhibition (reduced recall in pairs of people, relative to pooled individuals) across repeated retrieval attempts. Younger and older adults studied categorized word lists and were then given two consecutive recall tests and a recognition test. On the first recall test, the subjects were given free-report cued recall or forced-report cued recall instructions (Experiment 1) or free recall instructions (Experiment 2) and recalled the lists either alone or in collaboration with another subject of the same age group. Free-report cued recall and free recall instructions warned the subjects not to guess, whereas forcedreport cued recall instructions required them to guess. Collaborative inhibition was obtained for both younger and older adults on initial tests of free-report cued recall, forced-report cued recall, and free recall, showing that the effect generalizes across several tests for both younger and older adults. Collaborative inhibition did not persist on subsequent individual recall or recognition tests for list items. Older adults consistently falsely recalled and recognized items more than did younger adults, as had been found in previous studies. In addition, prior collaboration may exaggerate older adults' tendency toward higher false alarms on a subsequent recognition test, but only after a free recall test. The results provide generality to the phenomenon of collaborative inhibition and can be explained by invoking concepts of strategy disruption and source monitoring.
Two experiments examined collaborative memory for information that was studied by all group membe... more Two experiments examined collaborative memory for information that was studied by all group members (shared items) and information that was studied by only a subset of group members (unshared items). In both experiments significant collaborative inhibition (reduced output of the collaborative groups relative to the pooled output of individuals) was obtained for both shared and unshared information. In Experiment 1 the magnitude of collaborative inhibition was larger for unshared items than for shared items, possibly because unshared items were less likely to be acknowledged and thus incorporated into the groups' recall. In Experiment 2 the magnitude of collaborative inhibition for shared and unshared information was equivalent once all participants were provided with the category name associated with the shared and unshared items. The results of the experiments are discussed in relation to the retrieval strategy disruption hypothesis of collaborative inhibition and the role of social process variables, such as acknowledgement, in influencing collaborative inhibition across situations involving memory of shared and unshared information.
This study examined possible age-related differences in recall, guessing, and metacognition on fr... more This study examined possible age-related differences in recall, guessing, and metacognition on free recall tests and forced recall tests. Participants studied categorised and unrelated word lists and were asked to recall the items under one of the following test conditions: standard free recall, free recall with a penalty for guessing, free recall with no penalty for guessing, or forced recall. The results demonstrated interesting age differences regarding the impact of liberal test instructions (i.e., forced recall and no penalty) relative to more conservative test instructions (i.e., standard free recall and penalty) on memory performance. Specifically, once guessing was controlled, younger adults' recall of categorised lists varied in accordance with test instructions while older adults' recall of categorised lists did not differ between conservative and liberal test instructions, presumably because older adults approach standard free recall tests of categorised lists with a greater propensity towards guessing than young adults.
PeopleÕs knowledge about the world comes from many sources, including fictional ones such as movi... more PeopleÕs knowledge about the world comes from many sources, including fictional ones such as movies and novels.
Two experiments examined decay and additivity of semantic priming produced by DRM false memory li... more Two experiments examined decay and additivity of semantic priming produced by DRM false memory lists on a naming task. Subjects were presented with study lists containing 14 DRM items that were either all 14 related, the first 7 related, the second 7 related, or all 14 unrelated to the non-presented critical item. Priming was measured on a naming task that presented the critical item in test position 1, 3, or 9. Priming occurred for the 14 related list in the first position only. However, there was also evidence for long term semantic priming in other conditions that was not due to relatedness-checking. Across experiments, an underadditive pattern of activation was obtained. The results are interpreted within the context of Activation Monitoring Theory and suggest that the laws of rapid decay and additivity established for single prime target pairs may not apply to mixed DRM lists or delayed testing.
The nature of persisting spreading activation from list presentation in eliciting false recogniti... more The nature of persisting spreading activation from list presentation in eliciting false recognition in the Deese-Roediger-McDermott (DRM) paradigm was examined in two experiments. We compared the time course of semantic priming in the lexical decision task (LDT) and false alarms in speeded recognition under identical study and test conditions. The results revealed priming on the LDT only when a test item occurred immediately (1 s) after the last list item. In contrast, robust false recognition occurred across all delays in both experiments. We interpret the data as indicating that the automatic activation processes evidenced in lexical decision do not persist sufficiently long to produce the false recognition obtained in the DRM paradigm. False recognition occurs because episodic retrieval instructions and a related probe item create reactivation of a list's associative structure, but such reactivation does not occur in LDT under conditions in which subjects are discouraged from retrospective checking of the list.
In this study, we examined how implicit and explicit memory for perceptual information (modality ... more In this study, we examined how implicit and explicit memory for perceptual information (modality and voice) and lexical information varied across three subject groups: healthy young adults, healthy older adults, and age-matched older adults with dementia of the Alzheimer's type (DAT). These groups exhibited cross-modality (abstract) priming of the same magnitude. However, young adults produced greater modalityand voice-specific priming than the other two groups, whose performance was equivalent, suggesting that aging, but not DAT, reduced form-specific priming. Young adults demonstrated better recognition memory than healthy older adults, who in turn exhibited better recognition memory than older adults with DAT. In young adults, recognition memory was also sensitive to perceptual information. These findings indicate that aging can affect implicit memory for perceptual information, whereas DAT magnifies the effect of aging on explicit memory.
The effect of an initial forced recall test on later recall and recognition tests was examined in... more The effect of an initial forced recall test on later recall and recognition tests was examined in younger and older adults. Subjects were presented with categorized word lists and given an initial test under standard cued recall instructions (with a warning against guessing) or forced recall instructions (that required guessing); subjects were later given a cued recall test for the original list items. In 2 experiments, initial forced recall resulted in higher levels of illusory memories on subsequent tests (relative to initial cued recall), especially for older adults. Older adults were more likely to say they remembered rather than knew that forced guesses had occurred in the original study episode. The effect persisted despite a strong warning against making errors in Experiment 2. When a source monitoring test was given, older adults had more difficulty than younger adults in identifying the source of items they had originally produced as guesses. If conditions encourage subjects to guess on a first memory test, they are likely to recollect these guesses as actual memories on later tests. This effect is exaggerated in older adults, probably because of their greater source monitoring difficulties. Both dual process and source monitoring theories provide insight into these findings.
We report a new paradigm for studying false memories implanted by social influence, a process we ... more We report a new paradigm for studying false memories implanted by social influence, a process we call the social contagion of memory. A subject and confederate together saw six common household scenes (e.g., a kitchen) containing many objects, for either 15 or 60 sec. During a collaborative recall test, the 2 subjects each recalled six items from the scenes, but the confederate occasionally made mistakes by reporting items not from the scene. Some intrusions were highly consistent with the scene schema (e.g., a toaster) while others were less so (e.g., oven mitts). After a brief delay, the individual subject tried to recall as many items as possible from the six scenes. Recall of the erroneous items suggested by the confederate was greater than in a control condition (with no suggestion). Further, this social contagion effect was greater when the scenes were presented for less time (15 sec) and when the intruded item was more schema consistent (e.g., the toaster). As with other forms of social influence, false memories are contagious; one person's memory can be infected by another person's errors.
Experiments 1-3 were based on a master's thesis by M.L.M. conducted under supervision of H.L.R. W... more Experiments 1-3 were based on a master's thesis by M.L.M. conducted under supervision of H.L.R. We thank David A. Balota and Alan J. Lambert, the other members of the committee, for their advice and comment. We also thank Four experiments examined social influence on the development of false memories. We employed the social contagion paradigm: A subject and a confederate see scenes and then later take turns recalling items from the scenes, with the confederate erroneously reporting some items that were not present in the scenes; on a final test, the subject reports these suggested items when instructed to recall only items from the scenes.The first two experiments showed that the social contagion effect persisted when subjects were explicitly warned about the possibility that confederates' responses might induce false memories and when they were tested via source-monitoring tests that explicitly gave the choice of attributing suggested items to the other person. Levels of false recall and recognition increased with the number of times the misleading information was suggested (Experiment 3), and subjects were more likely to incorporate the erroneous responses of an actual confederate on a recognition/source test as compared with those of a simulated confederate (Experiment 4). Collectively, the data support the claim that false memories may be transmitted between people and reveal critical factors that modulate the social contagion of memories.
In two experiments, we examined age differences in collaborative inhibition (reduced recall in pa... more In two experiments, we examined age differences in collaborative inhibition (reduced recall in pairs of people, relative to pooled individuals) across repeated retrieval attempts. Younger and older adults studied categorized word lists and were then given two consecutive recall tests and a recognition test. On the first recall test, the subjects were given free-report cued recall or forced-report cued recall instructions (Experiment 1) or free recall instructions (Experiment 2) and recalled the lists either alone or in collaboration with another subject of the same age group. Free-report cued recall and free recall instructions warned the subjects not to guess, whereas forcedreport cued recall instructions required them to guess. Collaborative inhibition was obtained for both younger and older adults on initial tests of free-report cued recall, forced-report cued recall, and free recall, showing that the effect generalizes across several tests for both younger and older adults. Collaborative inhibition did not persist on subsequent individual recall or recognition tests for list items. Older adults consistently falsely recalled and recognized items more than did younger adults, as had been found in previous studies. In addition, prior collaboration may exaggerate older adults' tendency toward higher false alarms on a subsequent recognition test, but only after a free recall test. The results provide generality to the phenomenon of collaborative inhibition and can be explained by invoking concepts of strategy disruption and source monitoring.
Two experiments examined collaborative memory for information that was studied by all group membe... more Two experiments examined collaborative memory for information that was studied by all group members (shared items) and information that was studied by only a subset of group members (unshared items). In both experiments significant collaborative inhibition (reduced output of the collaborative groups relative to the pooled output of individuals) was obtained for both shared and unshared information. In Experiment 1 the magnitude of collaborative inhibition was larger for unshared items than for shared items, possibly because unshared items were less likely to be acknowledged and thus incorporated into the groups' recall. In Experiment 2 the magnitude of collaborative inhibition for shared and unshared information was equivalent once all participants were provided with the category name associated with the shared and unshared items. The results of the experiments are discussed in relation to the retrieval strategy disruption hypothesis of collaborative inhibition and the role of social process variables, such as acknowledgement, in influencing collaborative inhibition across situations involving memory of shared and unshared information.
This study examined possible age-related differences in recall, guessing, and metacognition on fr... more This study examined possible age-related differences in recall, guessing, and metacognition on free recall tests and forced recall tests. Participants studied categorised and unrelated word lists and were asked to recall the items under one of the following test conditions: standard free recall, free recall with a penalty for guessing, free recall with no penalty for guessing, or forced recall. The results demonstrated interesting age differences regarding the impact of liberal test instructions (i.e., forced recall and no penalty) relative to more conservative test instructions (i.e., standard free recall and penalty) on memory performance. Specifically, once guessing was controlled, younger adults' recall of categorised lists varied in accordance with test instructions while older adults' recall of categorised lists did not differ between conservative and liberal test instructions, presumably because older adults approach standard free recall tests of categorised lists with a greater propensity towards guessing than young adults.
PeopleÕs knowledge about the world comes from many sources, including fictional ones such as movi... more PeopleÕs knowledge about the world comes from many sources, including fictional ones such as movies and novels.
Two experiments examined decay and additivity of semantic priming produced by DRM false memory li... more Two experiments examined decay and additivity of semantic priming produced by DRM false memory lists on a naming task. Subjects were presented with study lists containing 14 DRM items that were either all 14 related, the first 7 related, the second 7 related, or all 14 unrelated to the non-presented critical item. Priming was measured on a naming task that presented the critical item in test position 1, 3, or 9. Priming occurred for the 14 related list in the first position only. However, there was also evidence for long term semantic priming in other conditions that was not due to relatedness-checking. Across experiments, an underadditive pattern of activation was obtained. The results are interpreted within the context of Activation Monitoring Theory and suggest that the laws of rapid decay and additivity established for single prime target pairs may not apply to mixed DRM lists or delayed testing.
The nature of persisting spreading activation from list presentation in eliciting false recogniti... more The nature of persisting spreading activation from list presentation in eliciting false recognition in the Deese-Roediger-McDermott (DRM) paradigm was examined in two experiments. We compared the time course of semantic priming in the lexical decision task (LDT) and false alarms in speeded recognition under identical study and test conditions. The results revealed priming on the LDT only when a test item occurred immediately (1 s) after the last list item. In contrast, robust false recognition occurred across all delays in both experiments. We interpret the data as indicating that the automatic activation processes evidenced in lexical decision do not persist sufficiently long to produce the false recognition obtained in the DRM paradigm. False recognition occurs because episodic retrieval instructions and a related probe item create reactivation of a list's associative structure, but such reactivation does not occur in LDT under conditions in which subjects are discouraged from retrospective checking of the list.
In this study, we examined how implicit and explicit memory for perceptual information (modality ... more In this study, we examined how implicit and explicit memory for perceptual information (modality and voice) and lexical information varied across three subject groups: healthy young adults, healthy older adults, and age-matched older adults with dementia of the Alzheimer's type (DAT). These groups exhibited cross-modality (abstract) priming of the same magnitude. However, young adults produced greater modalityand voice-specific priming than the other two groups, whose performance was equivalent, suggesting that aging, but not DAT, reduced form-specific priming. Young adults demonstrated better recognition memory than healthy older adults, who in turn exhibited better recognition memory than older adults with DAT. In young adults, recognition memory was also sensitive to perceptual information. These findings indicate that aging can affect implicit memory for perceptual information, whereas DAT magnifies the effect of aging on explicit memory.
The effect of an initial forced recall test on later recall and recognition tests was examined in... more The effect of an initial forced recall test on later recall and recognition tests was examined in younger and older adults. Subjects were presented with categorized word lists and given an initial test under standard cued recall instructions (with a warning against guessing) or forced recall instructions (that required guessing); subjects were later given a cued recall test for the original list items. In 2 experiments, initial forced recall resulted in higher levels of illusory memories on subsequent tests (relative to initial cued recall), especially for older adults. Older adults were more likely to say they remembered rather than knew that forced guesses had occurred in the original study episode. The effect persisted despite a strong warning against making errors in Experiment 2. When a source monitoring test was given, older adults had more difficulty than younger adults in identifying the source of items they had originally produced as guesses. If conditions encourage subjects to guess on a first memory test, they are likely to recollect these guesses as actual memories on later tests. This effect is exaggerated in older adults, probably because of their greater source monitoring difficulties. Both dual process and source monitoring theories provide insight into these findings.
Uploads
Papers by Michelle Meade