Task difficulty moderates the revelation effect

Tasks that precede a recognition probe induce a more liberal response criterion than do probes without tasks—the “revelation effect.” For example, participants are more likely to claim that a stimulus is familiar directly after solving an anagram, relative to a condition without an anagram. Revelation effect hypotheses disagree whether hard preceding tasks should produce a larger revelation effect than easy preceding tasks. Although some studies have shown that hard tasks increase the revelation effect as compared to easy tasks, these studies suffered from a confound of task difficulty and task presence. Conversely, other studies have shown that the revelation effect is independent of task difficulty. In the present study, we used new task difficulty manipulations to test whether hard tasks produce larger revelation effects than easy tasks. Participants (N = 464) completed hard or easy preceding tasks, including anagrams (Exps. 1 and 2) and the typing of specific arrow key sequences (Exps. 3–6). With sample sizes typical of revelation effect experiments, the effect sizes of task difficulty on the revelation effect varied considerably across experiments. Despite this variability, a consistent data pattern emerged: Hard tasks produced larger revelation effects than easy tasks. Although the present study falsifies certain revelation effect hypotheses, the general vagueness of revelation effect hypotheses remains.     

An event-related potential study of the revelation effect

Event-related potentials (ERPs) were recorded during a verbal recognition memory task in order to investigate whether changes in familiarity are part of the explanation for the revelation effect. For half of the test words, participants solved an anagram prior to making the old/new recognition judgment. A revelation effect was obtained: When test words were preceded by the anagram task, a higher probability of an old response was associated with the items than was otherwise the case. The ERPs recorded time-locked to the onset of the test words were separated according to old/new status andthe presence/absence of the anagram task. The ERP index of familiarity was of lower amplitude for both old and new items that were preceded by the anagram task. These findings are consistent with the view that part of the explanation for the revelation effect is a reduction in the familiarity of the critical test items.     

Conditions affecting the revelation effect for autobiographical memory

In four experiments involving 184 participants, people rated their confidence that particular events had happened in their childhood (e.g., "Broke a window playing ball"). If participants had to unscramble a key word in a phrase just before rating it (e.g., "Broke a nwidwo [window] playing ball"), confidence ratings increased-the revelation effect. However, the pattern of revelation effects depended on the particular way in which participants processed key words (e.g., visualizing vs. counting vowels in the word window) approximately 10 min prior to rating life events that contained those words. Prior exposure to key words never in itself directly affected confidence ratings. These results demonstrate that one can manipulate the revelation effect by altering the processing that participants perform on words prior to unscrambling them. These results also pose difficulties for many accounts of the revelation effect. The major puzzle posed by our present findings is that unscrambling key words increases confidence that an event has happened in childhood, whereas prior exposure to these words does not.     

The revelation effect in frequency judgment

In three experiments, we explored the revelation effect in a frequency judgment task. Participants estimated the frequency of words that had been presented one, two, four, or eight times. At test, half the words were revealed by completing word fragments, and half were presented intact. Estimated frequencies were reliably higher for revealed than for intact words, and in two of the three experiments, the revelation effect became larger as actual frequency increased. A revelation effect was obtained whether the revealed word was the same as (Experiment 1) or different from (Experiment 2) the word judged for frequency. Frequency estimates were higher for more distorted test items (Experiment 3).     

Recollection-based recognition eliminates the revelation effect in memory

The revelation effect refers to the tendency to call an item on a recognition test old if it is preceded by a cognitive task that involves the processing of a similar stimulus (Watkins &; Peynircioglu, 1990). It has been proposed that the revelation effect occurs because of an increase in the familiarity of the test items in the revelation condition (Luo, 1993; Westerman &; Greene, 1998). In the present experiments, the revelation effect was investigated in recognition tasks that were not based solely on the familiarity of the test items but,also, on a recall-like retrieval process. A revelation effect was not found on an associative-recognition task or on a plurality recognition task. The results of this study show that the revelation effect does not occur when the contribution of familiarity to recognition decisions is reduced by factors that encourage the recollection of the study episode.     

Altering the balance of recollection and familiarity influences the revelation effect

The revelation effect occurs when recognition test probes are more likely to be called "old" if they are preceded by a verbal processing task. Two experiments examined the role of familiarity and recollection in producing this effect. Each experiment tested the hypothesis that decreasing recollection would heighten the magnitude of the revelation effect. In Experiment 1, the revelation effect increased by delaying the recognition test. In Experiment 2, the revelation effect increased when the presentation rate of the study words was reduced. These results are discussed in terms of the variables that produce the revelation effect in episodic and nonepisodic memory judgments.     

The effect of the feeling of resolution and recognition performance on the revelation effect

The fact that engaging in a cognitive task before a recognition task increases the probability of “old” responses is known as the revelation effect. We used several cognitive tasks to examine whether the feeling of resolution, a key construct of the occurrence mechanism of the revelation effect, is related to the occurrence of the revelation effect. The results show that the revelation effect was not caused by a visual search task, which elicited the feeling of resolution, but caused by an unsolvable anagram task and an articulatory suppression task, which did not elicit the feeling of resolution. These results suggest that the revelation effect is not related to the feeling of resolution. Moreover, the revelation effect was likely to occur in participants who performed poorly on the recognition task. The result suggests that the revelation effect is inclined to occur when people depend more on familiarity than on recollection process.     

Judgments of remembering: the revelation effect in children and adults

When items on a recognition test are presented as a series of increasingly complete fragments rather than being presented initially in their fully intact form, adults' judgments of recognition exhibit an increased tendency to judge items as "old," an illusion of recognition referred to as the revelation effect. The present study used pictorial stimuli to test for a revelation effect with 4-year-olds, 8-year-olds, and adults (N = 76). A reliable revelation effect was found at all ages tested, indicating that the complex fluency-of-processing discrepancy detection and attribution mechanisms thought to be responsible for the effect function similarly across an age range from 4-years-of-age through adulthood. It was also found that the recognition decisions of the 8-year-olds and the adults were affected by how quickly they were able to identify a picture during the revelation phase of the recognition test. This effect was not found with the 4-year-olds, suggesting an age difference in the awareness and strategic use of an implicit memory effect when making explicit judgments of recognition.     

Aging, imagery, and the bizarreness effect

ABSTRACT This study examined the bizarre imagery effect in young and older adults, under incidental and intentional conditions. Intentionality was manipulated across experiments, with participants receiving an incidental free recall test in Experiment 1 and an intentional test in Experiment 2. This study also examined the relation between working memory resources and the bizarreness effect. In Experiment 1 young and older adults were presented with common and bizarre sentences; they later received an incidental recall test. There were no age differences in sensitivity to the bizarreness effect in Experiment 1 when ANOVAs were used to analyze the data. However, when the bizarreness effect was examined in terms of effect size, there was evidence that younger adults produced larger bizarreness effect sizes than younger adults. Experiment 2 further explored age differences in sensitivity to the bizarreness effect by presenting young and older adults with bizarre and common sentences under intentional learning conditions. Experiment 2 failed to yield age differences as a function of item type (bizarre vs. common). In addition, Experiment 2 failed to yield significant evidence that the bizarreness effect is modulated by working memory resources. The results of this study are most consistent with the distinctiveness account of the bizarreness effect.     

Recollective experience in the revelation effect: Separating the contributions of recollection and familiarity

The revelation effect is a phenomenon of recognition memory in which words presented for a recognition decision are more likely to be identified as previously studied if they are initially disguised and are then somehow revealed to the subject. The goal of the present experiments was to determine whether the revelation effect has similar or different influences on the conscious recollection of a previous encounter with a test item and on the feeling of familiarity evoked by a test item. The process-dissociation procedure (Experiment 1) and the remember/know procedure (Experiment 2) were used to achieve this goal. The main findings of these experiments were that revealing an item at test (1) increased the feeling of familiarity associated with that item, especially if it was not previously studied, and (2) decreased conscious recollection of previously studied items. These data narrow the range of potential explanations of the revelation effect.     

The revelation effect: A meta-analytic test of hypotheses

Judgments can depend on the activity directly preceding them. An example is the revelation effect whereby participants are more likely to claim that a stimulus is familiar after a preceding task, such as solving an anagram, than without a preceding task. We test conflicting predictions of four revelation-effect hypotheses in a meta-analysis of 26 years of revelation-effect research. The hypotheses’ predictions refer to three subject areas: (1) the basis of judgments that are subject to the revelation effect (recollection vs. familiarity vs. fluency), (2) the degree of similarity between the task and test item, and (3) the difficulty of the preceding task. We use a hierarchical multivariate meta-analysis to account for dependent effect sizes and variance in experimental procedures. We test the revelation-effect hypotheses with a model selection procedure, where each model corresponds to a prediction of a revelation-effect hypothesis. We further quantify the amount of evidence for one model compared to another with Bayes factors. The results of this analysis suggest that none of the extant revelation-effect hypotheses can fully account for the data. The general vagueness of revelation-effect hypotheses and the scarcity of data were the major limiting factors in our analyses, emphasizing the need for formalized theories and further research into the puzzling revelation effect.     

ROC curves show that the revelation effect is not a single phenomenon

The revelation effect describes the increased tendency to call itemsold when a recognition judgment is preceded by an incidental task. In theory, the effect could come about either from a more liberal response bias or from a change in underlying memory sensitivity. Using analyses of receiver-operating characteristic curves, we show that the revelation effect occurs for each of these reasons, but under different empirical conditions. A shift in response bias fully accounts for the revelation effect when revealed items are unrelated to the subsequent recognition probes. However, a change in memory sensitivity contributes to the effect when revealed items are identical to the recognition probes. Thus, the revelation effect encompasses at least two distinct phenomena.     

Interrupting recognition memory: Tests of familiarity-based accounts of the revelation effect

The revelation effect is a puzzling phenomenon in which items on a recognition test are more likely to be judged as "old" when they are immediately preceded by a problem-solving task, such as anagram solution. The present experiments were designed to evaluate Westerman and Greene's (1998) and Hicks and Marsh's (1998) familiarity-based accounts of this effect. We found comparable revelation effects when probes were preceded by an anagram or a numerical addition task and when subjects performed either one or two of these tasks. Taken together, the results do not support familiarity-based accounts of the revelation effect but are consistent with a proposed decision-based interpretation (i.e., criterion flux), in which it is assumed that the revelation task displaces the study list context in working memory, leading subjects to adopt a more liberal recognition decision criterion, thereby increasing the hit and false alarm rates.     

Aging and the misinformation effect: a neuropsychological analysis

Older adults' susceptibility to misinformation in an eyewitness memory paradigm was examined in two experiments. Experiment 1 showed that older adults are more susceptible to interfering misinformation than are younger adults on two different tests (old-new recognition and source monitoring). Experiment 2 examined the extent to which processes associated with frontal lobe functioning underlie older adults' source-monitoring difficulties. Older adults with lower frontal-lobe-functioning scores on neuropsychological tests were particularly susceptible to false memories in the misinformation paradigm. The authors' results agree with data from other false memory paradigms that show greater false recollections in older adults, especially in those who scored poorly on frontal tests. The results support a source-monitoring account of aging and illusory recollection.     

Aging and the strategic control of the fixation offset effect

A study was conducted to examine potential age-related differences in the strategic control of exogenous and endogenous saccades within the context of the fixation offset effect (FOE; i.e., faster saccades when a fixation point is removed than when it is left on throughout a trial). Subjects were instructed to make rapid saccades either on the basis of a suddenly appearing peripheral visual stimulus (exogenous saccade) or in response to a tone (endogenous saccade). On half of the trials the fixation point was removed simultaneously with the occurrence of the cue stimulus. Subjects' preparatory set was varied by manipulating the proportion of saccades generated to a visual and auditory stimulus within a trial block. Young and old adults both produced FOEs, and the FOEs were strategically modulated by preparatory set. The data are discussed in terms of aging and oculomotor control.     

The revelation effect for autobiographical memory: A mixture-model analysis

Participants provided information about their childhood by rating their confidence about whether they had experienced various events (e.g., “broke a window playing ball”). On some trials, participants unscrambled a key word from the event phrase (e.g., wdinwo—window) or an unrelated word (e.g., gnutge—nugget) before seeing the event and giving their confidence ratings. The act of unscrambling led participants to increase their confidence that the event occurred in their childhood, but only when the confidence rating immediately followed the act of unscrambling. This increase in confidence mirrors the “revelation effect” observed in word recognition experiments. In the present article, we analyzed our data using a new signal detection mixture distribution model that does not require the researcher to know the veracity of memory judgments a priori. Our analysis reveals that unscrambling a key word or an unrelated word affects response bias and discriminability in autobiographical memory tests in ways that are very similar to those that have been previously found for word recognition tasks.     

The revelation effect: when disguising test items induces recognition

Documented here is a bias whereby items are more likely to be judged as having been presented beforehand if they are disguised in some way and so have to be discovered or "revealed." The bias was found for test words that were unfolded letter by letter (Experiments 1 and 3), presented with their letters either transposed (Experiments 2 and 3), or individually rotated (Experiments 4 and 5), or rotated as a whole (Experiment 5), and for test numbers that were presented in the form of roman numerals (Experiment 6) or equations (Experiment 7). The bias occurred both for items that were presented beforehand and for those that were not. No bias was found when words were judged, not for prior occurrence, but for typicality as category instances (Experiment 8), lexicality (Experiment 9), frequency of general usage (Experiment 10), or number of times encountered during the preceding week (Experiment 11).     

The revelation effect for item and associative recognition: Familiarity versus recollection

The revelation effect occurs when items on a recognition test are more likely to be judged as being old if they are preceded by a cognitive task that involves the processing of similar types of stimuli. This effect was examined for item (single-word) and associative (word-pair) recognition. We found, in Experiments 1 and 2, a revelation effect for item, but not for associative recognition under normal study conditions. A revelation effect for both item and associative recognition was observed in Experiments 3 and 4 when study time was extremely brief, thus limiting the encoding of information that would support recall or recollection. In Experiment 5, we demonstrated that the revelation effect for item recognition is eliminated when item recognition decisions are made in the context of a study item. The results show that the revelation task influenced recognition decisions based on familiarity, but not decisions that involved recall or recollection.     

Interrupting recognition memory: Tests of a criterion-change account of the revelation effect

The revelation effect is evidenced by an increase in positive recognition responses when the test probe is immediately preceded by an unrelated problem-solving task. As an alternative to familiarity-based explanations of this effect (Hicks & Marsh, 1998; Westerman & Greene, 1998), Niewiadomski and Hockley (2001) proposed a decision-based account in which it is assumed that the problem-solving task displaces the study list context in working memory, leading subjects to adopt a more liberal recognition criterion. In the present study, we show that the revelation effect is seen when the stimulus materials are pure lists of very rare words or nonwords. In contrast, for mixed lists of common words and very rare words or nonwords, the revelation effect is found for common words but disappears for very rare words and nonwords. We argue that, in mixed lists, the liberal decision bias following the revelation task and the criterion changes between common words and very rare words and nonwords serve to offset each other.     

Increasing confidence in remote autobiographical memory and general knowledge: extensions of the revelation effect

In recognition tests, items presented in unusual ways (e.g., degraded, revealed in stages, or presented as anagrams) are often judged to be old more than are intact items. This revelation effect has been observed only in episodic judgments about the occurrence or frequency of relatively recent events. The present work extends the boundary conditions of this effect. In three experiments, subjects unscrambled anagrams in the context of answering questions about their childhood (e.g., broke a dwniwo playing ball) or while answering questions pertaining to world knowledge (e.g.,fastest animal-elpraod). In each case, a revelation effect was observed: Solving an anagram increased confidence in remote autobiographical memories and in memory for world facts. These results contradict claims that the effect is an episodic memory phenomenon and challenge existing explanations of the revelation effect.