Repeated checking really does cause memory distrust

Memory phenomena associated with obsessive-compulsive disorder (OCD) have received increased attention in the recent literature. Some debate remains about whether OCD is characterized by deficits in memory per se, or by poor memory confidence. Following from a recent study that demonstrated memory distrust results from repeated checking of a virtual computerized stove, we asked 50 undergraduate students to repeatedly turn on, turn off and check either a real kitchen stove (relevant checking) or a real kitchen faucet (irrelevant checking) in a standardized, ritualized manner. All participants completed a final check of the stove following these 19 checking trials. Results indicated that following repeated relevant checking, participants reported significantly reduced memory confidence, vividness and detail. Repeated irrelevant checking did not produce these decreases. Results are discussed in terms of cognitive-behavioural formulations of OCD and in terms of the effects of repetition on memory and metamemory.     

Deteriorating memory confidence, responsibility perceptions and repeated checking: comparisons in OCD and control samples

Repeated checking has been repeatedly associated with memory distrust. We sought to extend previous research using a computer-based checking task by incorporating a group of 15 individuals with OCD, and examining the effect of increased perceived responsibility. Participants were asked to repeatedly check a virtual stovetop, with half the participants also placed under a condition of high-perceived responsibility. Our observations replicated previous research showing that the act of repeatedly checking leads to reductions in memory vividness, detail and confidence, without accompanying reductions in memory accuracy. Furthermore, while a sense of increased personal responsibility had little effect on a student control sample, it led to a significant further deterioration in memory confidence in individuals with OCD. These results suggest that in people with OCD, normal reductions in memory confidence over repeated trials are exacerbated and intensified by inflated responsibility perceptions.     

Repeated checking causes memory distrust

This paper attempts to explain why in obsessive-compulsive disorder (OCD) checkers distrust in memory persists despite extensive checking. It is argued that: (1) repeated checking increases familiarity with the issues checked; (2) increased familiarity promotes conceptual processing which inhibits perceptual processing; (3) inhibited perceptual processing makes recollections less vivid and detailed and finally; (4) reduction in vividness and detail promotes distrust in memory. An interactive computer animation was developed in which participants had to perform checking rituals on a virtual gas stove. Two separate experiments were carried out with n=39 (Experiment I) and n=40 (Experiment II) healthy participants. In both studies, the control group and the experimental group were given the same pre-test and post-test on the virtual gas stove. In between, the experimental group engaged in 'relevant checking', i.e. checking the gas stove, while the control group engaged in 'irrelevant checking', i.e. checking virtual light bulbs. In both experiments there were powerful effects of repeated 'relevant checking': while actual memory accuracy remained unaffected, the vividness and detail of the recollections were greatly reduced. Most pertinently, in both experiments relevant checking undermined confidence in memory. No such effects were observed in the control group. One might argue that the pre-test/post-test design may have made the control group anticipate a memory assessment at the post-test and that this artifact made them relatively alert producing memory confidence at post test that was artificially high. A third experiment was carried out (n=2 x 20) in which no pre-test was given while, other than that, Experiment III was identical to the first two experiments. Results confirmed earlier findings: compared to the irrelevant checking control group, recollections in the relevant checking group were non-vivid, non-detailed while confidence in memory was low. The theory and data suggest an answer to the question 'why memory distrust persists despite repetitive checking'. In people who check extensively, memory distrust may persist as a result of repetitive checking. OCD checking may be motivated by the wish to reduce uncertainty, but checking appears to be a counter-productive safety strategy. Rather than reducing doubt, checking fosters doubt and ironically increases meta-memory problems.     

Exploring the boundaries of memory distrust from repeated checking: increasing external validity and examining thresholds

Checking behavior is among the most common forms of compulsions in OCD. Recent research suggests that repeated checking decreases memory confidence, and supports theoretical models of how repeated checking is maintained. The current paper presents findings from two studies exploring the boundaries of memory distrust from repeated checking. Results of study 1 show that repeated checking of a real stove decreases memory confidence, vividness, and detail (i.e., metamemory), and leads to a greater reliance on knowing as a source of memory, without meaningfully altering memory accuracy. Results of study 2 suggest that these changes in metamemory are observed after performing a relatively low number of checks on one occasion. The findings are considered within the context of theoretical models of checking and future directions are delineated.     

A mood-as-input account of perseverative checking: the relationship between stop rules, mood and confidence in having checked successfully

The present paper reports the results of two experiments designed to test predictions from the mood-as-input account of perseverative checking. Using an analogue checking task, both experiments showed that perseveration, as indicted by a range of measures relevant to compulsive checking, was affected by the configuration of the stop rule for the task and mood at the outset of checking. Perseveration was most significant in the condition that most closely resembled the characteristics of obsessive-compulsive checkers (negative mood combined with a stop rule that specifies that the task should be done as thoroughly as possible--namely, an 'as many as can' stop rule). The studies also indicated that confidence at having completed the checking task successfully was (1) significantly related to the use of 'as many as can' stop rules at the outset of checking, (2) mood ratings at the end of checking, and (3) checking perseveration generally. These findings provide support for a mood-as-input explanation of perseverative psychopathologies such as compulsive checking, and begin to cast some light on how anxiety-reduction and 'confidence' models of compulsive checking, might be explained within broader mechanisms of perseveration.     

Repeated checking causes distrust in memory but not in attention and perception

Repeated checking to reduce memory distrust seems to be counterproductive: it increases memory distrust. Obsessive-compulsive (OC) patients tend to be uncertain about other cognitive domains as well, like attention and perception. In an experiment with 70 healthy participants, we tested whether perseverative checking induces distrust not only in memory, but also in attention and perception. Participants were administered a computer task in which they had to activate, deactivate, and check threat-irrelevant stimuli, and rate their confidence in memory, attention, and perception in a pre-test and post-test. In between these tests, the relevant checking group performed 20 checks of the same stimuli used in the pre- and post-test. The irrelevant checking group performed 20 checks of different stimuli. Although memory accuracy improved in both groups, repeated checking reduced confidence in memory, vividness, and detail in the relevant checking group, but not in the irrelevant checking group. A trend was found towards a decline in attentional confidence in the relevant checking group only. Perception was not affected by repetitive checking. A replication study revealed similar results of relevant checking on meta-memory, however, the trend for attentional distrust was not confirmed. The results suggest that perseveration may be domain specific, i.e., only the cognitive processes that are subject to perseveration are affected.     

Believe in yourself: Manipulating beliefs about memory causes checking

One of the most common compulsions in obsessive–compulsive disorder (OCD) is repeated checking. Although individuals often report that they check to become more certain, checking has been shown to have the opposite effect – increased checking causes increased uncertainty. However, checking may also be thought of as beginning because of memory uncertainty. Beliefs about responsibility, over-estimation of threat, intolerance of uncertainty, perfectionism, and importance of and control of thoughts are already known to affect different aspects of OCD symptomatology. Beliefs about memory, however, are not currently considered to influence compulsive behaviour. In the current study, beliefs about memory were manipulated to test whether or not they affected urges to check. Ninety-one undergraduate participants received (positive or negative) false feedback about their performance on aspects of a standardized memory test, and then completed two additional memory tasks. Their urges to check following these tasks were assessed. Consistent with our hypotheses, individuals in the low memory confidence condition had greater urges to check following the memory tasks than those in the high memory confidence condition, demonstrating that manipulations of beliefs about memory can influence checking. Results and implications are discussed in terms of cognitive-behavioural models of and treatments for OCD.     

Relationships between anger, symptoms, and cognitive factors in OCD checkers

The purpose of this study was to examine whether individuals diagnosed with obsessive-compulsive disorder (OCD) with primary checking compulsions report higher levels of trait anger and anger expression compared with a student control group, and whether trait anger and anger expression are correlated with specific beliefs and interpretations that are common among individuals who compulsively check. A group of individuals with OCD reporting significant checking compulsions (n=33) and a group of undergraduate students (n=143) completed a questionnaire package that included measures of trait anger and anger expression, as well as measures of obsessive-compulsive symptoms and beliefs. The compulsive checking group reported greater trait anger, though not greater anger expression, than the student control group. Furthermore, beliefs concerning perfectionism and intolerance of uncertainty were positively correlated with anger expression and trait anger among compulsive checkers but not among the student control group. The implications of these findings are discussed in terms of cognitive-behavioural treatments for and models of compulsive checking in OCD.     

Children's false memory and true disclosure in the face of repeated questions

The current study was designed to investigate children's memory and suggestibility for events differing in valence (positive or negative) and veracity (true or false). A total of 82 3- and 5-year-olds were asked repeated questions about true and false events, either in a grouped order (i.e., all questions about a certain event asked consecutively) or in a nongrouped order (i.e., questions about a certain event were interspersed with questions about other events). Interviewer gender was also varied. Individual differences, including attachment style, inhibition, and behavioral adjustment, were examined as potential predictors of memory and suggestibility. Results revealed significant age, valence, and veracity effects on children's memory reports. Path analysis demonstrated that individual differences in behavioral problems and inhibitory ability predicted children's provision of inaccurate information. Implications for psychological theory and legal application are discussed.     

Cognitive behavioral therapy for compulsive buying disorder

To our knowledge, no psychotherapy treatment studies for compulsive buying have been published. The authors conducted a pilot trial comparing the efficacy of a group cognitive behavioral intervention designed for the treatment of compulsive buying to a waiting list control. Twenty-eight subjects were assigned to receive active treatment and 11 to the waiting list control group. The results at the end of treatment showed significant advantages for cognitive behavioral therapy (CBT) over the waiting list in reductions in the number of compulsive buying episodes and time spent buying, as well as scores on the Yale–Brown Obsessive Compulsive Scale—Shopping Version and the Compulsive Buying Scale. Improvement was well-maintained at 6-month follow-up. The pilot data suggests that a cognitive behavioral intervention can be quite effective in the treatment of compulsive buying disorder. This model requires further testing.     

How checking breeds doubt: Reduced performance in a simple workingmemory task

A paradox of memory research is that repeated checking results in a decrease in memory certainty, memory vividness and confidence [van den Hout, M. A., & Kindt, M. (2003a). Phenomenological validity of an OCD-memory model and the remember/know distinction. Behaviour Research and Therapy, 41, 369-378; van den Hout, M. A., & Kindt, M. (2003b). Repeated checking causes memory distrust. Behaviour Research and Therapy, 41, 301-316]. Although these findings have been mainly attributed to changes in episodic long-term memory, it has been suggested [Shimamura, A. P. (2000). Toward a cognitive neuroscience of metacognition. Consciousness and Cognition, 9, 313-323] that representations in working memory could already suffer from detrimental checking. In two experiments we set out to test this hypothesis by employing a delayed-match-to-sample working memory task. Letters had to be remembered in their correct locations, a task that was designed to engage the episodic short-term buffer of working memory [Baddeley, A. D. (2000). The episodic buffer: a new component in working memory? Trends in Cognitive Sciences, 4, 417-423]. Of most importance, we introduced an intermediate distractor question that was prone to induce frustrating and unnecessary checking on trials where no correct answer was possible. Reaction times and confidence ratings on the actual memory test of these trials confirmed the success of this manipulation. Most importantly, high checkers [cf. VOCI; Thordarson, D. S., Radomsky, A. S., Rachman, S., Shafran, R, Sawchuk, C. N., & Hakstian, A. R. (2004). The Vancouver obsessional compulsive inventory (VOCI). Behaviour Research and Therapy, 42(11), 1289-1314] were less accurate than low checkers when frustrating checking was induced, especially if the experimental context actually emphasized the irrelevance of the misleading question. The clinical relevance of this result was substantiated by means of an extreme groups comparison across the two studies. The findings are discussed in the context of detrimental checking and lack of distractor inhibition as a way of weakening fragile bindings within the episodic short-term buffer of Baddeley's (2000) model. Clinical implications, limitations and future research are considered.     

A sham drug improves a demanding prospective memory task

Every day, people rely on prospective memory—our ability to remember to perform a future action—to carry out myriad tasks. We examined how a sham cognitive enhancing drug might improve people's performance on a prospective memory task. We gave some people (but not others) the sham drug, and asked everyone to perform a high-effort prospective memory task. People who received the sham drug performed better on the prospective memory task. They also took longer to perform their ongoing task, suggesting that they increased their effortful monitoring. These results fit with research showing that suggestions can lead people to increase cognitive effort and increase memory performance.     

Overcoming fixation with repeated memory suppression

Fixation (blocks to memories or ideas) can be alleviated not only by encouraging productive work towards a solution, but, as the present experiments show, by reducing counterproductive work. Two experiments examined relief from fixation in a word-fragment completion task. Blockers, orthographically similar negative primes (e.g., ANALOGY), blocked solutions to word fragments (e.g., A_L_ _GY) in both experiments. After priming, but before the fragment completion test, participants repeatedly suppressed half of the blockers using the Think/No-Think paradigm, which results in memory inhibition. Inhibiting blockers did not alleviate fixation in Experiment 1 when conscious recollection of negative primes was not encouraged on the fragment completion test. In Experiment 2, however, when participants were encouraged to remember negative primes at fragment completion, relief from fixation was observed. Repeated suppression may nullify fixation effects, and promote creative thinking, particularly when fixation is caused by conscious recollection of counterproductive information.     

Manipulating memory associations changes decision-making preferences in a preconditioning task

Memories of past experiences can guide our decisions. Thus, if memories are undermined or distorted, decision making should be affected. Nevertheless, little empirical research has been done to examine the role of memory in reinforcement decision-making. We hypothesized that if memories guide choices in a conditioning decision-making task, then manipulating these memories would result in a change of decision preferences to gain reward. We manipulated participants’ memories by providing false feedback that their memory associations were wrong before they made decisions that could lead them to win money. Participants’ memory ratings decreased significantly after receiving false feedback. More importantly, we found that false feedback led participants’ decision bias to disappear after their memory associations were undermined. Our results suggest that reinforcement decision-making can be altered by false feedback on memories. The results are discussed using memory mechanisms such as spreading activation theories.     

Intrahippocampal insulin improves memory in a passive-avoidance task in male wistar rats

The main impacts of insulin favor the peripheral organs. Although it functions as a neuropeptide, insulin possesses also some central effects. The aim of this study was to determine the effect of intrahippocampal infusion of insulin on passive avoidance learning in healthy male rats. Thirty male wistar rats were divided into three groups (n=10 each). The experimental group had posttraining insulin infusion into the CA1 region of dorsal hippocampus, after which they were compared with sham (saline) and control (intact) groups. Insulin treated animals had greater latency to enter the dark compartment in compare with saline treated (p=0.023) or control groups (p=0.017). Upon our results, we concluded that intrahippocampal injections of insulin may enhance memory for a simple learning task which supports the concept that insulin possibly plays an endogenous role in memory formation.     

Response-time evidence for mixed memory states in a sequential-presentation change-detection task

Response-time (RT) and choice-probability data were obtained in a rapid visual sequential-presentation change-detection task in which memory set size, study-test lag, and objective change probabilities were manipulated. False “change” judgments increased dramatically with increasing lag, consistent with the idea that study items with long lags were ejected from a discrete-slots buffer. Error RTs were nearly invariant with set size and lag, consistent with the idea that the errors were produced by a stimulus-independent guessing process. The patterns of error and RT data could not be explained in terms of encoding limitations, but were consistent with the hypothesis that long retention lags produced a zero-stimulus-information state that required guessing. Formal modeling of the change-detection RT and error data pointed toward a hybrid model of visual working memory. The hybrid model assumed mixed states involving a combination of memory and guessing, but with higher memory resolution for items with shorter retention lags. The work raises new questions concerning the nature of the memory representations that are produced across the closely related tasks of change detection and visual memory search.     

Factors influencing infants’ ability to update object representations in memory

Remembering persisting objects over occlusion is critical to representing a stable environment. Infants remember hidden objects at multiple locations and can update their representation of a hidden array when an object is added or subtracted. However, the factors influencing these updating abilities have received little systematic exploration. Here we examined the flexibility of infants’ ability to update object representations. We tested 11-month-olds in a looking-time task in which objects were added to or subtracted from two hidden arrays. Across five experiments, infants successfully updated their representations of hidden arrays when the updating occurred successively at one array before beginning at the other. But when updating required alternating between two arrays, infants failed. However, simply connecting the two arrays with a thin strip of foam-core led infants to succeed. Our results suggest that infants’ construal of an event strongly affects their ability to update memory representations of hidden objects. When construing an event as containing multiple updates to the same array, infants succeed, but when construing the event as requiring the revisiting and updating of previously attended arrays, infants fail.     

Storing information in-the-world: Metacognition and cognitive offloading in a short-term memory task

We often store to-be-remembered information externally (e.g., written down on a piece of paper) rather than internally. In the present investigation, we examine factors that influence the decision to store information in-the-world versus in-the-head using a variant of a traditional short term memory task. In Experiments 1a and 1b participants were presented with to-be-remembered items and either had to rely solely on internal memory or had the option to write down the presented information. In Experiments 2a and 2b participants were presented with the same stimuli but made metacognitive judgments about their predicted performance and effort expenditure. The spontaneous use of external storage was related both to the number of items to be remembered and an individual’s actual and perceived short-term-memory capacity. Interestingly, individuals often used external storage despite its use affording no observable benefit. Implications for understanding how individuals integrate external resources in pursuing cognitive goals are discussed.     

Executive functioning and processing speed in age-related differences in memory: Contribution of a coding task

The aim of the present study was to examine executive dysfunctioning and decreased processing speed as potential mediators of age-related differences in episodic memory. We compared the performances of young and elderly adults in a free-recall task. Participants were also given tests to measure executive functions and perceptual processing speed and a coding task (the Digit Symbol Substitution Test, DSST). More precisely, we tested the hypothesis that executive functions would mediate the age-related differences observed in the free-recall task better than perceptual speed. We also tested the assumption that a coding task, assumed to involve both executive processes and perceptual speed, would be the best mediator of age-related differences in memory. Findings first confirmed that the DSST combines executive processes and perceptual speed. Secondly, they showed that executive functions are a significant mediator of age-related differences in memory, and that DSST performance is the best predictor.     

The effect of arousal on memory for emotionally-relevant information: a study of skydivers

The aim of the present study was to test memory for information under conditions of extreme arousal in an analogue design to mimic hyperarousal during trauma exposure. Prior to their skydive, 70 novice skydivers were administered measures of fear, heart rate, and anxiety sensitivity. Half the participants learnt a list of words that varied in both relevance to their skydive and valence (irrelevant/relevant, negative/neutral) on the plane (skydivers), and remaining participants learnt an identical list of words on the ground (delayed controls). Following the skydive, participants completed free recall and recognition tasks; heart rate, dissociation, and subjective arousal were also measured. Consistent with an attentional narrowing hypothesis, skydivers recalled comparable a comparable number of relevant words as delayed controls, but significantly less irrelevant words. In terms of recognition performance, skydivers displayed better recognition of relevant words but poorer recognition of irrelevant words than delayed controls. Valence of words did not alter the pattern of results. The implications of the findings are discussed in the context of understanding memory processes under conditions of high threat.