Reality monitoring and resistance to forgetting under short delay intervals

In three experiments, participants were asked to perform simple action statements or to imagine performing the actions in a single study session. In a test session that occurred 1 hr, 24 hr, 48 hr (Experiments 1a and 1b), or 1 week later (Experiments 2 and 3), participants were instructed to tell whether the action statement had been carried out or imagined. The primary finding was that, overall, recognition and reality monitoring showed a comparable rate of forgetting. The results add evidence to the hypothesis that, also after long retention delays, discrimination between an internal and an external source may not be inferior to item recognition. A new theoretical proposal to account for these findings is outlined.     

Evoking false beliefs about autobiographical experience

In two experiments, we demonstrate that laboratory procedures can evoke false beliefs about autobiographical experience. After shallowly processing photographs ofreal-world locations, participants returned 1 week (Experiments 1 and 2) or 3 weeks (Experiment 2) later to evaluate whether they had actually visited each of a series of new and old pictured locations. Mundane and unique scenes from an unfamiliar college campus (Duke or SMU) were shown zero, one, or two times in the first session. Prior exposure increased participants' beliefs that they had visited locations that they had never actually visited. Furthermore, participants gave higher visit ratings to mundane than to unique scenes, and this did not vary with exposure frequency or delay. This laboratory procedure for inducing autobiographical false beliefs may have implications for better understanding various illusions of recognition.     

Book review

In two experiments, participants were asked to perform simple action statements or to imagine performing the actions one, two, or four times in a single study session. The lag between repetitions could vary from 5 to 10 intervening items in Experiment 1 or be fixed at 0 and 4 in Experiment 2. In a test session that occurred either 24 or 48 hours later, participants were instructed to recognise statements only if they had occurred during the first session and, if recognised, to tell whether the action statement had been carried out or imagined. The primary finding was that it is possible to obtain an imagination inflation effect (that is, as repeated imaginations increase, participants are more likely to remember an action as performed) using a within-list paradigm. However, this outcome occurred only for spaced repetitions. The results are consistent with the hypothesis that repeated imagination increases the level of familiarity, which may, in turn, generate this memory illusion.     

The relationship between online visual representation of a scene and long-term scene memory

In 3 experiments the author investigated the relationship between the online visual representation of natural scenes and long-term visual memory. In a change detection task, a target object either changed or remained the same from an initial image of a natural scene to a test image. Two types of changes were possible: rotation in depth, or replacement by another object from the same basic-level category. Change detection during online scene viewing was compared with change detection after delay of 1 trial (Experiments 2A and 2B) until the end of the study session (Experiment 1) or 24 hr (Experiment 3). There was little or no decline in change detection performance from online viewing to a delay of 1 trial or delay until the end of the session, and change detection remained well above chance after 24 hr. These results demonstrate that long-term memory for visual detail in a scene is robust.     

Memory for actions: Self-performed tasks and the reenactment effect

Encoding action phrases by enactment (self-performed tasks, or SPTs) leads to better memory than does observing actions (experimenter-performed tasks, or EPTs) or hearing action phrases (Engelkamp, 1998). In addition, recognition memory for SPTs is enhanced when test items are reenacted. Experiment 1 demonstrated a reenactment effect for EPTs, as well as for SPTs, indicating that the effect can be based on visual, as well as motoric, feedback. However, the reenactment effect in SPTs was found even when the participants were blindfolded at test (Experiment 2), indicating that the basis for the reenactment effect differs across SPTs and EPTs. Experiments 3 and 4 provided additional evidence that visual feedback is not critical for reenactment recognition in the case of SPTs. In addition, these experiments failed to show a hand congruency effect (enhanced recognition when the same hand enacts at study and at test), indicating that this effect is not as generalizable as the reenactment effect. These results have important implications for the motor-encoding hypothesis of the enactment effect.     

Perceiving performer identity and intended expression intensity in point-light displays of dance

This study investigated agent and expression intensity recognition in point-light displays depicting dancing performances. In a first session, participants danced with two different expression intensities to music, solo or in dyads. In a subsequent session, they watched point-light displays of 1–5-s duration, depicting their own, their partner’s or another participant’s recorded actions, and were asked to identify the agent (self vs. partner vs. stranger) and the intended expression intensity (expressive vs. inexpressive) of the performer. The results indicate that performer identity and expression intensity could be discerned reliably from displays as short as 1 s. The accuracy in judgment increased with exposure duration and, for performer identification, with higher expression intensity. Judgment accuracy in agent and expression intensity recognition tasks correlated with self-report empathy indices. Accuracy correlated also with confidence in judgment, but only in the intensity recognition task. The results are discussed in relation to perceptual and neural mechanisms underlying action and intention recognition.     

Instrumental performance following reinforcer devaluation depends upon incentive learning

Conditioning an aversion to the reinforcer following instrumental training reduces performance in a subsequent extinction test. Three experiments examined whether this reinforcer-devaluation effect depends upon experience with the devalued reinforcer prior to the extinction test. In Experiments 1 and 2 thirsty rats were trained to press a lever for sucrose solution in a single session. All animals then received an injection of lithium chloride (LiCl) either immediately following the session or after a delay of 6 hr. On the next day either the sucrose solution or water was presented non-contingently either in the operant chamber without the lever present or in a separate drinking cage. In a subsequent extinction test only the animals that had received immediate LiCl and re-exposure to non-contingent sucrose pressed less than those in the delayed-LiCl control groups. Experiment 3 demonstrated that this difference depended, at least in part, on post-conditioning exposure to a contingent reinforcer. Lever pressing and chain pulling were reinforced concurrently with either a sucrose or a sodium chloride solution in a single session immediately before the administration of LiCl. All animals then received non-contingent presentations of one of the reinforcers in the absence of both manipulanda. Finally, performance of both actions was assessed in an extinction test. Re-exposure to a reinforcer produced a relative reduction in the performance of its associated action on test. These results are interpreted as evidence that the instrumental reinforcer devaluation effect depends upon a process of incentive learning.     

Viewpoint-dependent Priming Effects in the Perception of Human Actions and Body Postures

The identification of human actions and body postures viewed from different viewpoints was examined in four long-term priming experiments with static pictures of a human model. In Experiments 1 and 2 participants had to name or describe the pictures, and in Experiments 3 and 4 participants had to decide whether the pictures showed a possible or impossible body pose. Reliable priming effects were obtained only when priming and primed action or pose shared the same in-depth orientation (Experiments 1 and 4) and left-right reflection (Experiments 2 and 3). Having seen the same action or pose in a different orientation did not reliably facilitate identification performance later on. Also, there was no priming for poses that are impossible to perform with a human body, not even when an identical same-view prime was used. These findings suggest that the stored representations that mediate the identification of human actions and postures are viewpoint specific.     

Experimental dissociations between memory measures: Influence of retrieval strategies

The objective of this study was to explore the participants’ processing strategies on the mere exposure effect, object decision priming and explicit recognition. In Experiments 1, we observed that recognition and the mere exposure effect for unfamiliar three-dimensional objects were not dissociated by plane rotations in the same way as recognition and object decision priming. However, we showed that, under identical conditions, prompting analytic (part-based) processing at testing produced a large plane rotation effect on recognition and the mere exposure effect similar to that observed for object decision priming (Experiment 2). Furthermore, inducing a non-analytic (whole-based) processing strategy at testing produced a reduced plane rotation effect on recognition and object decision (Experiments 3 and 4), similar to that observed for the mere exposure effect. These findings suggest that participants’ processing strategies influence performance on the three tasks.     

Recollection, fluency, and the explicit/implicit distinction in artificial grammar learning

In this article, the authors propose that both implicit memory and implicit learning phenomena can be explained by a common set of principles, in particular via participants' strategic use of recollective and fluency heuristics. In a series of experiments, it was demonstrated that manipulating processing fluency had an impact on classification decisions in an artificial grammar learning task (Experiments 1, 2, 4, and 7), showing that participants were using a fluency heuristic. Under identical conditions, however, this manipulation had no effect on recognition decisions (Experiments 3 and 5), consistent with a greater default reliance on recollection. Most significant, the authors also showed that a fluency effect can be induced in recognition (Experiments 4-6) and can be eliminated in classification (Experiment 7).     

Perspective taking combats the denial of intergroup discrimination

Despite the continuing, adverse impact of discrimination on the lives of racial and ethnic minorities, the denial of discrimination is commonplace. Four experiments investigated the efficacy of perspective taking as a strategy for combating discrimination denial. Participants who adopted a Black or Latino target's perspective in an initial context were subsequently more likely to explicitly acknowledge the persistence of intergroup discrimination than were non-perspective takers (Experiments 1–3) or participants who adopted a White target's perspective (Experiment 1). Perspective taking also engendered more positive attitudes toward a social policy designed to redress intergroup inequalities (i.e., affirmative action), and this relationship was mediated by increased recognition of discrimination (Experiments 2a and 2b). Increased identification with the targeted outgroup, as reflected in automatic associations between the self and African Americans, was found to underlie the effect of perspective taking on sensitivity to discrimination (Experiment 3). The collective findings indicate that perspective taking can effectively combat discrimination denial.     

Familiarity from orthographic information: Extensions of the recognition without identification effect

Two experiments were conducted to investigate the effect of letter location information in recognition memory judgments. The experiments used the recognition without identification paradigm (Peynircioglu, 1990), in which participants first attempt to identify the test item and then make a recognition decision as to whether or not the item was studied. In these studies, items that are not identified but that correspond to items that were presented are typically still rated as more likely to have been studied than those that were not presented. The present experiments demonstrated this finding with a variant of the conjunction lure paradigm. In Experiments 1 and 2, participants were tested with word fragments that were made from the letters of two words. When the letters were from studied items, fragments were rated higher than when the test items were derived from two unstudied items, or one studied item and one unstudied item, suggesting that recognition without identification is prone to the same types of errors as recognition with identification. Results are discussed in terms of familiarity effects in recognition memory.     

Imagination inflation for action events: Repeated imaginings lead to illusory recollections

In two experiments, subjects heard simple action statements (e.g., “Break the toothpick”), and, in some conditions, they also performed the action or imagined performing the action. In a second session that occurred at a later point (10 min, 24 h, 1 week, or 2 weeks later), subjects imagined performing actions one, three, or five times. Some imagined actions represented statements heard, imagined, or performed in the first session, whereas other statements were new in the second session. During a third (test) phase, subjects were instructed to recognize statements only if they had occurred during the first session and, if recognized, to tell whether the action statement had been carried out, imagined, or merely heard. The primary finding was that increasing the number of imaginings during the second session caused subjects to remember later that they had performed an action during the first session when in fact they had not (imagination inflation). This outcome occurred both for statements that subjects had heard but not performed during the first session and for statements that had never been heard during the first session. The results are generally consistent with Johnson, Hashtroudi, and Lindsay’s (1993) source monitoring framework and reveal a powerful memory illusion: Imagining performance of an action can cause its recollection as actually having been carried out.     

Positive mood + action = negative mood + inaction: effects of general action and inaction concepts on decisions and performance as a function of affect

General action and inaction concepts have been shown to produce broad, goal-mediated effects on cognitive and motor activity irrespective of the type of activity. The current research tested a model in which action and inaction goals interact with the valence of incidental moods to guide behavior. Over four experiments, participants' moods were manipulated to be positive (happy), neutral, or negative (angry or sad), and then general action, inaction, and neutral concepts were primed. In Experiment 1, action primes increased intellectual performance when participants experienced a positive (happy) or neutral mood, whereas inaction primes increased performance when participants experienced a negative (angry) mood. Including a control-prime condition, Experiments 2 and 3 replicated these results measuring the number of general interest articles participants were willing to read and participants' memory for pictures of celebrities. Experiment 4 replicated the results comparing happiness with sadness and suggested that the effect of the prime's adoption was automatic. Overall, the findings supported an interactive model by which action concepts and positive affect produce the same increases in active behavior as inaction concepts and negative affect.     

What happens to information to be suppressed in working-memory tasks? Short and long term effects

The study explored, from an individual differences point of view, what happens to information to be suppressed in a working-memory task at short and long term. In particular, it was examined whether control mechanisms of irrelevant information in working memory imply their complete elimination from working memory or just the modulation of their activation. To this end, we compared the fate of irrelevant information in groups of subjects with high and low reading comprehension (Experiments 1 and 2) and subjects with high and low working memory (Experiments 1, 2, 3, and 4). All the experiments presented a working-memory task devised by De Beni, Palladino, Pazzaglia, and Cornoldi (1998), which required participants to process lists of words, to tap when a word from a particular category was presented, and then to recall only the last items in each list. Results confirmed that participants with high reading comprehension also have higher working memory and make less intrusion errors due to irrelevant items that have to be processed but then discarded. Furthermore, it was found that participants with low working memory have slightly better implicit (Experiment 1) and explicit memory (Experiments 3 and 4) of highly activated irrelevant information. Nevertheless, in a long-term recognition test, participants with high and low reading comprehension/working memory presented a similar pattern of memory for different types of irrelevant information (Experiment 2), whereas in a short-term memory recognition test, low-span participants presented a facilitation effect in the time required for the recognition of highly activated irrelevant information (Experiment 4). It was concluded that efficient working-memory performance is related to the temporary reduction of activation of irrelevant information but does not imply its elimination from memory.     

Assessing the effectiveness of warnings and the phenomenological characteristics of false memories

The phenomenology of false memories was investigated in three experiments in which participants heard two experimenters read lists of items that were related to critical nonpresented items. In Experiments 1, following a recognition memory test, participants rated the phenomenological characteristics of their memories immediately and after a 48-hour delay. False recognition was prevalent and on several dimensions participants rated their true memories as more vivid than their false memories. In Experiments 2 and 3, following the study phase, participants were warned about the phenomenological differences between true and false memories and were instructed to use this information to avoid reporting nonpresented items. This type of warning was ineffective at reducing false recall (Experiment 2) and false recognition (Experiment 3) relative to unwarned participants. Importantly, the inability of explicit warnings to impact illusory recollections demonstrates that the false memories cannot be attributed simply to a criterion shift.     

Creating nonbelieved memories for bizarre actions using an imagination inflation procedure

The current experiments examined the creation of nonbelieved true and false memories after imagining bizarre and familiar actions using the imagination inflation procedure (Goff & Roediger, 1998). In both experiments, participants took part in three sessions. In Session 1, participants had to perform or imagine simple familiar actions (e.g., “stir the water with the spoon”) and bizarre actions (e.g., “balance the spoon on your nose”). A day later, participants needed to imagine simple actions of which some were new actions, and some were old actions that appeared in the first session. After a week, the participants completed a recognition task. For those actions that were correctly or incorrectly remembered as having been performed, the participant was challenged that the action was not performed in order to evoke nonbelieved true and false memories. In general, we found that the imagination inflation procedure can successfully induce participants to produce nonbelieved memories. In Study 1, we successfully induced nonbelieved memories for bizarre actions, although in general nonbelieved memory rates were low. In Study 2, more participants formed nonbelieved memories for bizarre actions than for familiar actions. Also, we found that especially belief was more susceptible to revision when memories were challenged than recollection. In two experiments, we showed that nonbelieved memories can successfully be induced for both familiar and bizarre actions.     

Assessing the effectiveness of warnings and the phenomenological characteristics of false memories

The phenomenology of false memories was investigated in three experiments in which participants heard two experimenters read lists of items that were related to critical nonpresented items. In Experiments 1, following a recognition memory test, participants rated the phenomenological characteristics of their memories immediately and after a 48-hour delay. False recognition was prevalent and on several dimensions participants rated their true memories as more vivid than their false memories. In Experiments 2 and 3, following the study phase, participants were warned about the phenomenological differences between true and false memories and were instructed to use this information to avoid reporting nonpresented items. This type of warning was ineffective at reducing false recall (Experiment 2) and false recognition (Experiment 3) relative to unwarned participants. Importantly, the inability of explicit warnings to impact illusory recollections demonstrates that the false memories cannot be attributed simply to a criterion shift.     

Bias or equality? Unconscious thought equally integrates temporally scattered information

In previous experiments on unconscious thought, information was presented to participants in one continuous session; however, in daily life, information is delivered in a temporally partitioned way. We examined whether unconscious thought could equally integrate temporally scattered information when making overall evaluations. When presenting participants with information in two temporally partitioned sessions, participants’ overall evaluation was based on neither the information in the first session (Experiment 1) nor that in the second session (Experiment 2); instead, information in both sessions were equally integrated to reach a final judgment. Conscious thought, however, overemphasized information in the second session. Experiments 3 and 4 further ruled out possible influencing factors including differences in the distributions of positive/negative attributes in the first and second sessions and on-line judgment. These findings suggested that unconscious thought can integrate information from a wider range of periods during an evaluation, while conscious thought cannot.     

Production and recognition bias of stylistic sentences using a story reading task

Four experiments examined participants' ability to produce surface characteristics of sentences using an on-line story reading task. Participants read a series of stories in which either all, or the majority of, sentences were written in the same style, or surface form. Twice per story, participants were asked to fill in a blank consistent with the story. For sentences that contained three stylistic regularities, participants imitated either all three characteristics (Experiment 2) or two of the three characteristics (Experiment 1), depending on the proportion of in-style sentences. Participants demonstrated a recognition bias for the read style in an unannounced recognition task. When participants read stories in which the two styles were the dative/double object alternation, participants demonstrated a syntactic priming effect in the cloze task, but no consistent recognition bias in a later recognition test (Experiments 3 and 4).