Retrieval‐induced forgetting: A developmental study

Two studies examined the possibility of retrieval‐induced forgetting by 7‐year‐olds. Children heard a story while viewing pictures of events mentioned in the story, each highlighting objects drawn from two distinct semantic categories (e.g. animals and food). Over the next several days, children were asked the same yes/no questions about half the examples from one category and, finally, were tested for their memory of the complete set of examples from both categories. Both a category‐cued recall test (Study 1) and a written recognition‐memory test (Study 2) produced results suggestive of retrieval‐induced forgetting. That is, children showed poorer memory for unpractised items from the practised category than for unpractised items from the other category. The severity of the effect did not differ reliably between the children and young adults, and was unaffected by whether practised items appeared before or after the unpractised competitors (Study 2). We consider the implications of these findings for competing views about retrieval‐induced forgetting and the development of cognitive inhibition.     

Retrieval‐induced forgetting is inversely relatedto everyday cognitive failures

It has recently been suggested ( Anderson, 2003 ) that forgetting is an adaptive process arising from successful inhibition of unwanted items, rather than arising from a failure of the memory system. This inhibition process is thought to make use of retrieval‐induced forgetting (RIF). In the present study, individual susceptibility to RIF was measured in a group of 40 normal participants, whose RIF scores were then compared with their scores on the Cognitive Failures Questionnaire (CFQ). A significant inverse correlation was found between RIF and CFQ scores, indicating that individuals who show a strong RIF effect tend to suffer a lower rate of cognitive failures and forgetfulness in everyday life. These findings are consistent with the hypothesis that RIF might play a role in facilitating memory function by assisting selective retrieval.     

Forgetting Trauma: Socially Shared Retrieval‐induced Forgetting and Post‐traumatic Stress Disorder

Memory for related but unpracticed aspects of an event can be impaired by selectively retrieving parts of the same event. This occurs when selective retrieval [within‐individual retrieval‐induced forgetting (WI‐RIF)] is undertaken by individuals and has been extended to social contexts—RIF can be produced in listeners [socially shared retrieval‐induced forgetting (SS‐RIF)] by a speaker's selective recounting. The effects of post‐traumatic stress disorder (PTSD) on WI‐RIF and SS‐RIF were examined by two experiments. In Experiment 1, combat veterans (with or without PTSD) and non‐veteran dyads participated in a RIF paired‐associates paradigm adapted for combat‐related stimuli. WI‐RIF and SS‐RIF occurred for combat‐related and neutral pairs regardless of group. However, greater WI‐RIF and SS‐RIF for combat‐related words were shown by individuals with PTSD. These findings were replicated by Experiment 2, in which either a combat‐related or neutral story was learned by participants, and selective retrieval was embedded in a conversation. That the selective retrieval of trauma‐related stimuli leads to enhancement of induced forgetting for individuals with PTSD under certain conditions is suggested by these data. Copyright © 2011 John Wiley & Sons, Ltd.     

Applying Retrieval‐Induced Forgetting to Children's Testimony

When a crime has been committed, investigators must obtain as much and as accurate information as possible from witnesses. Initial incomplete interviews may pose a potential cost to unretrieved information. We explored retrieval‐induced forgetting (RIF) in children's autobiographical memory for related episodic events. Children experienced four related play sessions across 4 days, followed by word stem retrieval practice of half of the items, and a cued recall task that took place either 15 minutes or 2 hours later. Categorized details were experienced either within a single day or across multiple days. The emergence of RIF was dependent upon the length of delay between practice and test phases and the temporal distribution of the episodic events. Our observations demonstrate that RIF can be a subtle phenomenon whose occurrence depends upon whether the retrieval context supports an environment of retrieval interference. Copyright © 2012 John Wiley & Sons, Ltd.     

The contribution of category‐based and contextual suppression towards retrieval‐induced forgetting1

Abstract: This study examines whether both context‐related and category‐related memory impairment can be found using a retrieval‐induced forgetting procedure. One group of participants was tested using a standard retrieval‐practice paradigm, whereas for the no‐practice group the retrieval practice was replaced by irrelevant filler activity. The results showed that the within‐participant baseline items were recalled more poorly by the practice group than by the no‐practice group, whereas the practice group showed the standard retrieval‐induced forgetting effect. Thus, retrieval practice impaired recall for both within‐category and baseline items, although it impaired the former to a greater extent. This finding suggests that it is necessary to consider not only categorical relationships between items, but also context information shared by items when exploring retrieval‐induced forgetting.     

Patterns of errors in short-term forgetting in AD and ageing

This study examined whether the low performance of 40 AD patients in the Brown-Peterson task could be explained by a pattern of errors that differed from 55 elderly controls. Our quantitative results showed that AD patients had a lower performance level in the three retention intervals than controls but a significant interaction between group and interval was not found, indicating that the rate of forgetfulness was similar in the two groups. In our qualitative analysis, errors were categorised as confusions, perseverations, omissions, and order alterations. Contrary to other studies (Dannenbaum, Parkinson, & Inman, 1988; Kopelman, 1985) where an AD forgetfulness tendency of omissions was observed, our data showed an excess of perseveration (even more than five repetitions), indicating problems in the central executive. This could be interpreted in terms of problems in updating the contents of working memory.     

Repeated partial eyewitness questioning causes confidence inflation but not retrieval‐induced forgetting

During a crime investigation eyewitnesses are often interviewed more than once. Repeated post‐event questioning offers an opportunity for retrieval practice. Practicing retrieval of a subset of memories may suppress access to related memories, a phenomenon known as retrieval‐induced forgetting. In this short report we investigated the generalization of retrieval‐induced forgetting to episodic eyewitness memory of a complex event. The results indicated that repeated retrieval improves future recall of practiced information, but does not induce forgetting of related information. Retrieval practice, however, did result in higher confidence ratings, both for correct and incorrect answers. The practical consequence of this study is that repeated questioning should be avoided if possible. Not because it may induce retrieval‐induced forgetting, but because it may lead to confidence inflation. Copyright © 2008 John Wiley & Sons, Ltd.     

The role of outcome inhibition in interference between outcomes: A contingency‐learning analogue of retrieval‐induced forgetting

Current associative theories of contingency learning assume that inhibitory learning plays a part in the interference between outcomes. However, it is unclear whether this inhibitory learning results in the inhibition of the outcome representation or whether it simply counteracts previous excitatory learning so that the outcome representation is neither activated nor inhibited. Additionally, these models tend to conceptualize inhibition as a relatively transient and cue‐dependent state. However, research on retrieval‐induced forgetting suggests that the inhibition of representations is a real process that can be relatively independent of the retrieval cue used to access the inhibited information. Consistent with this alternative view, we found that interference between outcomes reduces the retrievability of the target outcome even when the outcome is associated with a novel (non‐inhibitory) cue. This result has important theoretical implications for associative models of interference and shows that the empirical facts and theories developed in studies of retrieval‐induced forgetting might be relevant in contingency learning and vice versa.     

Selective retrieval and induced forgetting in eyewitness memory

This study analyses retrieval‐induced forgetting (RIF) in eyewitness memory. Selective retrieval of specific information about an event could cause eyewitnesses to forget related contents. Based on a video of a man being robbed while withdrawing money from a cash machine, we examined the effects of partial retrieval on the most relevant aspects of the event: actions (Experiment 1) and offender characteristics (Experiment 2), in both immediate and long‐term recall (24 hours). In both experiments long‐term recall was a replica of immediate recall for correct information as well as errors. The effects of partial retrieval practice were also repeated in long‐term recall. Conventional RIF was found for offender characteristics but selective retrieval of the actions of the event produced no comparable effect. It is assumed that the organisation and integration of the actions of the event protected them from RIF. Copyright © 2006 John Wiley & Sons, Ltd.     

Effects of post‐cue interval on intentional forgetting

This study examined the effect of post‐cue interval on directed forgetting and suppression. Experiments 1 and 2 used the item method of directed forgetting. The interval between the cue to remember/forget (R/F) and the presence of the next item was manipulated. As the post‐cue interval increased, the rates of hits and ‘remember’ responses on the recognition test also increased not only for R items but also for F items, suggesting that participants did not stop processing F items after the F cue. Experiment 3 manipulated both the number of response/suppression attempts and the duration of response/suppression for each word pair during the response/suppression phase. The results showed that increasing the number of suppression attempts led to worse recall in the subsequent memory test. However, increasing the duration of suppression reduced the suppression effect. These results provide insights into a key factor for successful intentional forgetting and suppression.     

Segregation accuracy in item‐method directed forgetting across multiple tests

Two experiments examined recall across tests following item‐method directed‐forgetting instructions and the varying of presentation duration of items at study. For both immediate testing (Experiment 1) and delayed testing (Experiment 2), accurate recall of remember instruction items (R‐items) exceeded the accurate recall of forget instruction items (F‐items). However, some F‐items from study were inaccurately recalled as R‐items and R‐items from study as F‐items. Inaccurate recall persisted across tests for both immediate and delayed recall and increased across tests for immediate recall. We view the R‐item advantage in accurate recall as consistent with the account they receive more rehearsal at study than do F‐items. We view inaccurate recall as reflecting the bias to report items retrieved on an immediate test lacking instructional tags as F‐items. On delayed tests, items retrieved lacking instructional tags are first assessed against a criterion point on a memory‐strength continuum and those with strength above the criterion reported as R‐items and those below the criterion as F‐items.     

Thinking about “why” eliminates retrieval‐induced forgetting: Levels of construal affect retrieval dynamics

The present study examined how levels of construal affect retrieval‐induced forgetting. Higher‐level construal is associated with the focus on the similarities among stimuli, suggesting that high‐level construal promotes relational processing. Based on this fact, retrieval‐induced forgetting may be reduced or eliminated under high‐level construal condition because of the effect of relational processing. Two experiments were conducted using a retrieval‐practice paradigm with different stimuli while priming the level of construal. A meta‐analysis synthesizing the results showed that retrieval‐induced forgetting occurred under the low‐level construal condition, whereas forgetting did not occur under the high‐level construal condition. These results suggest that abstract thinking can eliminate retrieval‐induced forgetting because of relational processing, demonstrating the role of the levels of construal on memory inhibition.     

Source‐monitoring accuracy across repeated tests following directed forgetting

The repeated recall of items from lists that participants were earlier instructed to either remember or to forget was examined in two experiments. RR participants (those instructed to remember both lists they were presented) tended to recall more List 1 items than FR participants (those instructed to forget the first list and to remember the second list). FR participants recalled more List 2 items than did RR participants, but only when directed to report those items (Experiment 1), not when directed to report items from both lists (Experiment 2). Participants experienced difficulty correctly reporting the list source of items they recalled and incorrect source recall increased across tests, showing hypermnesia. This later result underscores the need for caution when assessing the accuracy of information retrieved from multiple sources across repeated tests. Together, the data patterns provide support for the retrieval dynamics account of hypermnesia, the context‐change account of directed forgetting, and limited support for the retrieval inhibition view of directed forgetting.     

You were always on my mind: The importance of “significant others” in the attenuation of retrieval‐induced forgetting in Japan

Research on memory has demonstrated that remembering material can cause forgetting of related information, which is known as retrieval‐induced forgetting (RIF). Macrae and Roseveare identified “self” as one of the boundary conditions of this effect in the Western cultural context, showing that RIF was eliminated when material was encoded to be related to the self (known as self‐referential effect), but not to significant others. In this study, we predicted and found that significant others could be another boundary condition in Japanese cultural contexts in which self and agency are more interdependent or conjoint; RIF was observed neither under best‐friend‐related encoding nor under family‐related encoding in Japan. The effect of significant others is found uniquely in Japanese cultural contexts, suggesting that the cultural model of self has significant power in the spontaneous system of memory.     

Explicit and implicit memory in dementia and normal ageing

Summary In two experiments, young subjects, healthy elderly subjects (spouses), and highly intelligent elderly subjects (elite elderly), were compared with dementia patients in a variety of explicit and implicit memory tasks, to investigate two issues: whether priming in Alzheimer-type dementia is contingent upon the presence of pre-existing representations, and whether intelligence modulates performance in explicit memory tasks in healthy ageing. Dementia patients performed as well as spouses in a homophone-spelling task. Moreover, they established new contextual associations when memory was tested by word-stem completion. The hypothesis that priming in dementia is contingent upon pre-existing memory representations was not supported. Spouses, elite elderly, and young subjects did not differ in their ability to recognize correctly recently heard stimuli or to complete word stems. However, recall of lists of words and paired associates was better in both young and elite elderly subjects than in spouses. It is concluded that intellectual capacity rather than chronological age in healthy subjects modulates performance in explicit-memory tasks.Now at The Social Psychiatry Unit, Australian National University, Canberra, ACT, Australia     

Retrieval‐induced forgetting of emotional and unemotional autobiographical memories

This experiment extended the retrieval‐induced forgetting (RIF) procedure from simple, episodic information to emotional and unemotional autobiographical memories. In the elicitation phase, participants generated specific memories from their past in response to negative, neutral, or positive category cues. In the retrieval‐practice phase, they practised retrieving (and elaborated further on) some of the memories for some of the categories. In the final test phase, they tried to recall all memories. Memories that received retrieval practice were recalled more often on final test than baseline memories, whereas memories that were not practised, yet competed with practised memories via a shared category cue, were recalled less often than baseline memories. We discuss the roles of inhibition, competition, emotion, and self‐relevance, and consider what laboratory manipulations of memory might reveal about everyday and pathological personal memory.     

The sufficient conditions for directed forgetting in normal and educable mentally retarded adolescents

A series of studies investigated the conditions under which normal and educable mentally retarded adolescents (13 to 15 years old) would or would not disregard irrelevant information in memory. A directed forgetting task was used in which the person was required to recall short sequences of picture names. In some sequences there was a cue to forget the first few pictures (irrelevant information) and to remember only the subsequent pictures (relevant information). When normal adolescents were given no explanation of the forget cue, there was interference from the irrelevant information. A minimum explanation of the cue, however, was sufficient to eliminate interference for the normal adolescents. The same minimal explanation was not sufficient for mentally retarded adolescents. It was clear that irrelevant information in memory interfered with the performance of retarded adolescents given only a minimal explanation of the forget cue. These results are important since most naturalistic situations do not involve an elaborate explanation of the importance of disregarding irrelevant information previously stored in memory.     

Searching for genetic influences on normal cognitive ageing

Differences in non-pathological cognitive ageing provide a useful case study for the opportunities and challenges facing cognitive science as it embraces advances in genetics. One replicated contributor to these differences is variability in the gene for apolipoprotein E. Genetic variations that influence neurodegenerative diseases, learning and memory, cardiovascular disease, and oxidative stress are among the candidates for influence on cognitive ageing differences. The area suffers the same problems as other domains in which quantitative trait loci are sought: uncertainty regarding the genetic architecture, unreliable strategies for candidate gene selection, lack of power leading to unreplicated findings, and poor characterisation of the phenotype. However, current progress in genetic knowledge, technology and informatics will contribute to progress in this important area.     

Destination memory and cognitive theory of mind in normal ageing

Destination memory is the ability to remember the destination to which a piece of information has been addressed (e.g., “Did I tell you about the promotion?”). This ability is found to be impaired in normal ageing. Our work aimed to link this deterioration to the decline in theory of mind. Forty younger adults (M age = 23.13 years, SD = 4.00) and 36 older adults (M age = 69.53 years, SD = 8.93) performed a destination memory task. They also performed the False-belief test addressing cognitive theory of mind and the Reading the mind in the eyes test addressing affective theory of mind. Results showed significant deterioration in destination memory, cognitive theory of mind and affective theory of mind in the older adults. The older adults’ performance on destination memory was significantly correlated with and predicted by their performance on cognitive theory of mind. Difficulties in the ability to interpret and predict others’ mental states are related to destination memory decline in older adults.