Directed forgetting in acute stress disorder.

The rationale underpinning the diagnosis of acute stress disorder is that cognitive mechanisms result in avoidant processing of aversive experiences. This study investigated acutely traumatized participants with either acute stress disorder (ASD; n=15) or no ASD (n=14) and nontraumatized comparison participants (n=16). Participants were administered intermixed presentations on a computer screen of positive, neutral, and trauma-related words that were followed by instructions to either remember or forget each word. On a subsequent recall test, ASD participants displayed poorer recall of to-be-forgotten trauma-related words than did non-ASD participants. Severity of psychopathology was negatively correlated with to-be-remembered positive words. These findings are consistent with the proposal that people who develop ASD display an aptitude for superior forgetting of aversive material. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Directed forgetting of emotional words.

Emotional material may induce processing limitations affecting memory performance. In the present study, the authors investigated how the emotional content of words influences the degree to which participants can be directed to forget them. In Experiment 1, the authors found that negative-valence words were recalled better when participants were told to forget them than when they were told to remember them. This effect was only obtained when a study-list of negative words was presented after the cue to remember or forget the first list. The effect was correlated with negative mood as assessed by the PANAS. Similar results were obtained in Experiment 2, in which the induction of negative arousal by a mild stressor abolished the directed forgetting of words when the following study list was comprised of negative words. These results support the idea that directed forgetting relies on cognitive control processes that may be disrupted by negative emotion. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Directed forgetting of recently recalled autobiographical memories.

In 6 experiments, the authors investigated list-method directed forgetting of recently recalled autobiographical memories. Reliable directed forgetting effects were observed across all experiments. In 4 experiments, the authors examined the impact of memory valence on directed forgetting. The forget instruction impaired recall of negative, positive, and neutral memories equally, although overall, participants recalled fewer unemotional memories than emotional memories. The preexisting organization of memories enhanced the directed forgetting effect, and a release from forgetting occurred only when the forgotten memories were directly cued. The authors discuss the roles of emotion, retrieval dynamics, and organization in these effects and suggest that the directed forgetting of recently recalled autobiographical memories may reflect the inhibition of recently formed memories of remembering, that is, episodic inhibition. The authors consider the implications of these findings for the control of autobiographical remembering in everyday life. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Directed forgetting: Comparing pictures and words.

The authors investigated directed forgetting as a function of the stimulus type (picture, word) presented at study and test. In an item-method directed forgetting task, study items were presented 1 at a time, each followed with equal probability by an instruction to remember or forget. Participants exhibited greater yes–no recognition of remember than forget items for each of the 4 study–test conditions (picture–picture, picture–word, word–word, word–picture). However, this difference was significantly smaller when pictures were studied than when words were studied. This finding demonstrates that the magnitude of the directed forgetting effect can be reduced by high item memorability, such as when the picture superiority effect is operating. This suggests caution in using pictures at study when the goal of an experiment is to examine potential group differences in the magnitude of the directed forgetting effect. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Directed forgetting of emotional stimuli in borderline personality disorder.

On the basis of clinical literature, the authors hypothesized that individuals with borderline personality disorder (BPD) would show biased information processing when they were exposed to negative affective stimuli of a particular type. Individuals with BPD and controls were tested using a directed forgetting paradigm. Study participants were exposed to 3 types of words (borderline, neutral, positive) and were cued to either remember or forget each word as it was presented. There were no group differences on a free recall task for words in the remember condition. However, participants with BPD recalled significantly more of the borderline words from the forget condition than did controls. In other words, borderline participants remembered borderline words that they were instructed to forget. These results may be consistent with enhanced encoding of salient words and perhaps related themes in BPD individuals. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Directed forgetting and intratrial interference in pigeon delayed matching.

In 3 experiments, 4 Silver King pigeons were tested in an intratrial interference preparation in which 2 stimuli (red and green fields) were presented successively as samples and then simultaneously as comparison stimuli. Choice of the comparison matching the 2nd sample was designated correct and was reinforced. On different trials, either the 1st or 2nd sample was followed by a cue to forget (horizontal line), and the alternate sample was followed by a cue to remember (vertical line). Relative to baseline trials in which both samples were followed by a cue to remember, accuracy was enhanced on trials in which the forget cue was presented immediately following the 1st sample and was reduced on trials in which the cue was presented following the 2nd sample. It is concluded that the context-retrieval interpretation of directed forgetting does not account for this pattern of findings; the rehearsal interpretation of directed forgetting provides a ready account of the data, an account tested and supported in the 3rd experiment. (French abstract) (14 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Directed forgetting meets the production effect: Distinctive processing is resistant to intentional forgetting.

The production effect refers to the fact that, relative to reading a word silently, reading a word aloud during study improves explicit memory. The authors tested the distinctiveness account of this effect using the item method directed forgetting procedure. If saying words aloud makes them more distinctive, then they should be more difficult to forget on cue than should words read silently. Participants studied a list of words by reading half aloud and half silently; half of the words in each of these subsets were followed by a Remember instruction and half were followed by a Forget instruction. There was a robust production effect for both Remember and Forget words on an explicit recognition test. Critically, however, a directed forgetting effect was observed only for words read silently; words read aloud at study were unaffected by memory instruction. An implicit speeded reading test showed equal priming for all studied items. This pattern supports a distinctiveness account of the production effect: Words processed distinctively during production are not influenced by subsequent rehearsal differences. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Intentional inhibition in memory and hallucinations: Directed forgetting and updating.

Hallucinations have been recently associated with inhibitory deficits in memory. In this study, the authors investigated whether hallucinations were related to difficulties to inhibit irrelevant information from episodic memory (Experiment 1) and working memory (Experiment 2). In Experiment 1, a directed forgetting task was used. This task measures participants' ability to intentionally forget some recently learned material, when instructions indicate that it is no longer relevant. In Experiment 2, an updating task was used. This task requires participants to intentionally suppress irrelevant information from working memory. Results showed that patients with schizophrenia with hallucinations presented inhibitory deficits in the directed forgetting task and an increase in the number of intrusions in the updating task, compared to patients without hallucinations and healthy controls. No correlations were found between indices of inhibition and other general, negative or positive symptoms. These findings support the existence of an association between intentional inhibition in memory and hallucinations, and they suggest that problems to suppress memory representations can underlie hallucinations in schizophrenia. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Directed forgetting following mood induction in chronic posttraumatic stress disorder patients.

Current research of posttrauma sequelae suggests that intrusive rather than avoidant-dissociative models more accurately represent the encoding processes of trauma cues. However, posttraumatic stress disorder (PTSD) is often conceptualized as a phasic phenomenon, altering between arousal and avoidance states. The failure to support a relationship between avoidant encoding style and PTSD may reflect this alteration. To explore this hypothesis, participants with PTSD and controls (no PTSD) completed an item-cued directed-forgetting task, following either a dissociative or a serenity (control) mood induction. Results suggested that, following the serenity induction, a standard directed-forgetting effect was observed. However, following the dissociation induction, this effect was not observed. The role of dissociation in impairing encoding via lack of selective rehearsal or source discrimination is discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Directed forgetting affects both direct and indirect tests of memory.

In two experiments, subjects were instructed either to remember or to forget each word. Following study, two tests were given, one a direct test of memory requiring conscious recollection of the study list and the other an indirect test that could be performed without awareness of the study list. In Experiment 1, subjects recognized more remember than forget words (direct test) and completed more remember than forget fragments (indirect test) on both immediate and 1-week delayed tests. In Experiment 2, subjects showed superior recall (direct test) and greater repetition priming in lexical decision (indirect test) for remember than for forget words. The consistent directed forgetting effect on both types of tests is in accord with the idea that forget items are inhibited at the time of retrieval and that retrieval manipulations, unlike elaboration manipulations at encoding, affect direct and indirect tests in similar ways. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Directed forgetting and posthypnotic amnesia: Information processing and social contexts.

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. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Directed forgetting between, but not within, dissociative personality states.

To investigate amnesia between identities in dissociative identity disorder (DID), the authors assessed explicit and implicit memory performance on a directed-forgetting task in 12 DID patients who switched from one state to an "amnesic" state between presentation and memory testing. DID patients were instructed either to remember or to forget neutral and emotional words. Besides an overall decrease in explicit memory, patients demonstrated selective forgetting of to-be-forgotten, but not of to-be-remembered words in the amnesic state. Patients did not exhibit any directed forgetting within the same state. Implicit memory was fully preserved across states. Independent of state, patients recalled more emotional than neutral information. These results may extend the conceptualization of memory processes in DID, suggesting an important role for retrieval inhibition. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Directed forgetting in implicit and explicit memory tests: A comparison of methods.

Directed forgetting has been studied by instructing Ss to forget either (1) an initial list or (2) individually selected words. Differential encoding was hypothesized to be responsible for word-method directed forgetting, and retrieval inhibition for list-method directed forgetting. In Exps 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 Exps 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. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Directed forgetting of trauma cues in adults reporting repressed or recovered memories of childhood sexual abuse.

An item-cuing directed forgetting task was used to investigate whether women reporting repressed (n?=?13) or recovered (n?=?13) memories of childhood sexual abuse (CSA) exhibit an avoidant encoding style (and resultant impaired memory) for trauma cues relative to women reporting no CSA experience (n?=?15). All participants viewed intermixed trauma (e.g., molested), positive (e.g., confident), and categorized neutral (e.g., mailbox) words on a computer screen and were instructed either to remember or to forget each word. The results provided no support for the hypothesis that people reporting either repressed or recovered memories of CSA are especially adept at forgetting words related to trauma. These groups recalled words they were instructed to remember more often than words they were instructed to forget regardless of whether they were trauma related. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Learning and forgetting in schizophrenia.

Recent studies of patients with schizophrenia have consistently demonstrated marked deficits on measures of initial learning. However, contradictory results have been reported concerning retention and forgetting. The present study examined the level of initial and delayed recall of stories and visual figures in a group of 76 patients with schizophrenia and 51 normal controls. Schizophrenia patients demonstrated marked impairments in initial and delayed recall as well as significantly worse percentage retention scores. However, schizophrenia patients and healthy controls individually matched on level of initial recall had nearly identical delayed recall performance. The results suggest a primary deficit in the initial acquisition of information rather than an accelerated rate of forgetting in schizophrenia. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The crucial role of postcue encoding in directed forgetting and context-dependent forgetting.

People can intentionally forget previously studied material if, after study, a forget cue is provided and new material is learned. It has recently been suggested that such list-method directed forgetting arises because the forget cue induces a change in internal context and causes context-dependent forgetting of the studied material (L. Sahakyan & C. M. Kelley, 2002). The authors compared directed forgetting and context-dependent forgetting by examining whether, like a forget cue, a change in internal context needs subsequent learning of new material to be effective. Participants studied an item list and, after study, received a remember cue or a forget cue or their internal context was changed through an imagination task. In each condition, half the participants learned a second list, and the other half fulfilled an unrelated distractor task. Both the forget cue and the change in internal context induced forgetting of the first list only when learning of the second list was interpolated. These results suggest that postcue encoding of new material is crucial for both directed forgetting and (some forms of) context-dependent forgetting. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Retrieval-induced forgetting in episodic memory.

Participants learned the locations of 12 stimuli that were uniquely colored but could be grouped by shape (4 circles, 4 triangles, 4 crosses). Following the study, a retrieval-practice phase required participants to recall the colors of a subset of the stimuli (i.e., 2 circles, 2 triangles) using shape and location as cues. In a final test, participants recalled the colors of all 12 stimuli. Compared with the control set of stimuli (i.e., 4 crosses), memory was facilitated for practiced items but impaired for related items, which were not practiced but shared the same shape group. Across experiments, retrieval-induced forgetting was observed for different perceptual groupings and for different cuing procedures. The effect, however, required retrieval of information during the interpolated phase. Providing extra presentations did not disrupt memory for related items. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Evaluating forgetting curves psychologically.

A theoretical treatment of forgetting is presented which uses scaled variables, provides a new definition of independence of rate of forgetting from initial level of learning, and provides an appropriate statistical test of that independence based on functional measurement methodology. It is shown that G. R. Loftus's (see record 1986-05498-001) horizontal interaction method leads to conclusions that are at odds with existing theory, and his conclusion that forgetting is slower for higher degrees of original learning is weakened thereby although it is consistent with his method. Arguments are given for preferring the method presented here. The N. J. Slamecka and B. McElree (see record 1984-05823-001) approach is rejected, but their conclusion that forgetting rate does not depend on original learning is supported. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Directed forgetting of trauma cues in adult survivors of childhood sexual abuse with and without posttraumatic stress disorder

The authors used a directed-forgetting task to investigate whether psychiatrically impaired adult survivors of childhood sexual abuse exhibit an avoidant encoding style and impaired memory for trauma cues. The authors tested women with abuse histories, either with or without posttraumatic stress disorder (PTSD), and women with neither abuse histories nor PTSD. The women saw intermixed trauma words (e.g., molested), positive words (e.g., confident), and categorized neutral words (e.g., mailbox) on a computer screen and were instructed either to remember or to forget each word. Relative to the other groups, the PTSD group did not exhibit recall deficits for trauma-related to-be-remembered words, nor did they recall fewer trauma-related to-be-forgotten words than other words. Instead, they exhibited recall deficits for positive and neutral words they were supposed to remember. These data are inconsistent with the hypothesis that impaired survivors exhibit avoidant encoding and impaired memory for traumatic information.     

Adult age differences in forgetting sentences.

Carried out age comparisons of performance-based measures of forgetting. In Exp 1, 18–21 yr olds and 55–64 yr olds (n?=?24) forgot at an equal rate when compared at 30 sec and 3, 6, and 24 hrs after acquisition. In Exp 2, 17–21 yr olds and 65–74 yr olds (n?=?24) were compared at the same 4 retention intervals. Initial learning was equated for the 2 groups. There was evidence for an age difference in forgetting rate in cued recall when a minimal learning level was required. In Exp 3, 440 men and women (aged 17–74 yrs) were assigned to a retention interval from 10 min to 7 hrs. Age was related to 4 performance-based measures of forgetting rate. Although the age differences were small, they imply 2 decremental processes: one before 10 min, possibly a result of incomplete consolidation, and a later one that is continuously and cumulatively operative thereafter. Evidence relating initial level to forgetting rate is presented. (PsycINFO Database Record (c) 2011 APA, all rights reserved)