List strength effect without list length effect in recognition memory

The study of list length effects (adding items to a list affects memory for the other items) and list strength effects (strengthening some items in a list affects memory for the nonstrengthened items) is important to constrain models of memory. In recognition memory, a list length effect is generally found, whereas a list strength effect is not. Using the switched-plurality procedure in an old–new recognition task (e.g., study banana; test bananas), we found the opposite pattern. Length manipulations caused no change in memory performance, whereas strength manipulations did. The list strength effect was found when recollection was likely to operate at test (with switched-plurality lures). When recollection was unlikely to operate (with unrelated lures), the strength effect disappeared. The result was observed using both a size judgement task (which has previously produced positive list strength effects) and a pleasantness judgement task (which has not yielded list strength effects before).     

Examining the basis for illusory recollection: The role of remember/know instructions

Curiously, studies using the remember/know paradigm to measure recollective experience show that people often vividly remember events that never occurred, a phenomenon referred to asillusory recollection. Two experiments tested the hypothesis that false remember responses in the converging associates, or Deese/Roediger-McDermott (DRM) paradigm, reflect accurate memory for the study episode, rather than false recollection of critical lures. To test this hypothesis, we used standard remember instructions that emphasized recollection of the study context by allowing participants to use memory of surrounding list items as evidence for recollection, or we used modified instructions that did not include memory for surrounding list items as a basis for recollection. Results showed that, as compared with the standard instruction condition, the modified instructions selectively reduced reports of false remember responses to critical lures, but did not affect remember responses to studied items. By contrast, remember responses to critical lures were unaffected by an instruction condition that excluded the use of voice information as evidence for remembering. These results suggest that remember responses to falsely recognized items are driven partly by retrieval of studied items, rather than illusory recollection of the critical lures themselves. They further point to the importance of instructions in influencing subjective reports.     

How do associative and phonemic overlap interact to boost illusory recollection?

This project investigated the underlying mechanisms that boost false remember responses when participants receive study words that are both semantically and phonologically similar to a critical lure. Participants completed a memory task in which they were presented with a list of words all associated with a critical lure. Included within the list of semantic associates was a target that was either semantically associated (e.g., yawn) to the critical lure (e.g., sleep) or shared the initial (e.g., slam) or final (e.g., beep) phoneme(s) with the critical lure. After hearing the list, participants recalled each list item and indicated whether they just knew it was on the list or if they instead recollected specific contextual details of that item’s presentation. We found that inserting an initial phonemic overlap target boosted experiences of recollection, but only when semantically related associates were presented beforehand. The results are consistent with models of spoken word recognition and show that established semantic context plus initial phonemic overlap play important roles in boosting false recollection.     

Subjective experience guides betting decisions beyond accuracy: evidence from a metamemory illusion

The goal of this research was to test whether subjective memory experiences drive accuracy regulation decisions above and beyond objective memory indices. In four experiments (n?=?115) subjective recollection (i.e., reporting “Remember” in the Remember-Know task) was dissociated from memory accuracy by manipulating retrieval during a two-alternative forced-choice recognition task: in the Match condition the distracter was a novel exemplar of the target (e.g., a studied and an unstudied toaster) and in the Non-match condition the distracter was a novel exemplar of another studied but untested item (e.g., a studied toaster and an unstudied birdhouse). Participants were more accurate on Match trials, but reported subjective recollection more frequently on Non-match trials. Critically, participants also bet more often on Non-match trials to the detriment of their score (Experiment 1). This pattern persisted when participants were additionally required to retrieve details about items (Experiment 2) and when confidence assessments were collected (Experiment 3). Finally, participants bet more on Non-match trials even when subjective judgments were not elicited, suggesting that the decision process does not require reporting on subjective experience (Experiment 4). These results indicate that subjective memory experiences guide decision-making independent of objective accuracy and thus are critical to accuracy regulation.     

List strength effect without list length effect in recognition memory

The study of list length effects (adding items to a list affects memory for the other items) and list strength effects (strengthening some items in a list affects memory for the nonstrengthened items) is important to constrain models of memory. In recognition memory, a list length effect is generally found, whereas a list strength effect is not. Using the switched-plurality procedure in an old-new recognition task (e.g., study banana; test bananas), we found the opposite pattern. Length manipulations caused no change in memory performance, whereas strength manipulations did. The list strength effect was found when recollection was likely to operate at test (with switched-plurality lures). When recollection was unlikely to operate (with unrelated lures), the strength effect disappeared. The result was observed using both a size judgement task (which has previously produced positive list strength effects) and a pleasantness judgement task (which has not yielded list strength effects before).     

A demonstration and comparison of two types of inference-based memory errors

Participants viewed slides depicting ordinary routines (e.g., going grocery shopping) and later received a recognition test. In Experiment 1, there was higher recognition confidence to high-schema-relevant than to low-schema-relevant items. In Experiment 2, participants viewed slide sequences that sometimes contained a cause (e.g., woman taking orange from bottom of pile) but not an effect scene (oranges on floor), or an effect but not a cause scene. Participants mistook new cause scenes as old when they viewed the effect; false alarms to cause scenes and high-schema-relevant items increased with retention interval. Experiment 3 showed that the backward inference effect was accompanied by false explicit recollection, whereas false alarms to schema-high foils were based on familiarity. This suggests that the 2 types of inferential errors are produced by different underlying mechanisms.     

The role of extralist associations in false

The finding that new items are judged as remembered in the remember-know paradigm presents a challenge to traditional process and systems accounts of memory. In three experiments, we demonstrated that false remember responses can be caused by misattributing recollection to a context other than the study list. In Experiments 1 and 2, false remember responses to distractors that were unrelated to studied words increased if they were encountered in a “preexposure” phase a few minutes or even a few days prior to the studied list. A third experiment demonstrated that remember responses to preexposed distractors increased when they were encoded in a manner similar to studied items, despite the more similar items being of weaker overall memory strength. We propose a source misattribution account of false remembering to explain these data, suggesting that all remember judgments reflect conscious recollection of contextual details, but false remember judgments are partly the result of recollection of details from an extralist context (i.e., from a source other than the study list).     

Not all sources of familiarity are created equal: the case of word frequency and repetition in episodic recognition

Low-frequency (LF) words produce higher hit rates and lower false alarm rates than high-frequency (HF) words. This word frequency mirror pattern has been interpreted within dual-process models of recognition, which assume the contributions of a slower recollective process and a relatively fast-acting familiarity process. In the present experiments, recollection and familiarity were placed in opposition using Jacoby, L. L., Journal of Memory and Language, 30, 513–541 (1991), two-list exclusion paradigm with HF and LF words. Exclusion errors to LF words exceeded those to HF words at fast deadlines, whereas the reverse occurred at slow deadlines. In Experiments 2 and 3, false alarms to HF nonpresented lures were higher than to LF nonpresented lures, indicating the use of baseline familiarity for totally new items. Combined, these results indicate that in addition to baseline familiarity and recollection, a third process involving the assessment of a relative change in familiarity is involved in recognition performance. Both relative changes in familiarity and recollection processes have distinct time courses and are engaged when there is diagnostic list information available, whereas baseline familiarity is used when there is no diagnostic information available (e.g., for nonpresented lure items).     

Remembering words not presented in sentences: How study context changes patterns of false memories

People falsely endorse semantic associates and morpheme rearrangements of studied words at high rates in recognition testing. The coexistence of these results is paradoxical: Models of reading that presume automatic extraction of meaning cannot account for elevated false memory for foils that are related to studied stimuli only by their visual form; models without such a process cannot account for false memory for semantic foils. Here we show how sentence and list study contexts encourage different encoding modes and consequently lead to different patterns of memory errors. Participants studied compound words, such as tailspin and floodgate, as single words or embedded in sentences. We show that sentence contexts led subjects to be better able to discriminate conjunction lures (e.g., tailgate) from old words than did list contexts. Conversely, list contexts led to superior discrimination of semantic lures (e.g., nosedive) from old words than did sentence contexts.     

Strategic influences on recollection in the exclusion task: Electrophysiological evidence

One assumption underlying the use of the exclusion task as part of the process dissociation procedure is that studied items are successfully excluded only when they are recollected. The present study employed event-related potentials (ERPs) to demonstrate that successful exclusion does not necessarily require recollection. In two experiments, the study tasks for to-be-excluded items were identical, but the tasks employed withtarget items differed, giving better memory for these items in Experiment 1 than in Experiment 2. Successfully excluded items elicited the ERP signature for recollection—theleft parietal old/new effect—in Experiment 2 only. These findings indicate that the subjects adopted different retrieval strategies in the two experiments. It is suggested that they made more use of source information about to-be-excluded items in the second experiment than in the first.     

The systematic discrepancy betweenA′ for overall recognition and remembering: A dual-process account

Signal detection accounts of recognition assume that all item endorsements arise from the assessment of a single continuous indication of memory strength, even when subjects claim to categorically separate items accompanied by contextual recollection from those that are not (viz., remembering vs. knowing). Dissociations of these response types are held to occur because the former require a higher response criterion for item strength than does the latter. Meta-analytic and individual subject data suggest that when theA′ metric is used, accuracy for remembering can systematically deviate from that of overall responding for individual subjects. This occurs because, unlike the symmetric and rigid receiveroperating characteristic (ROC) implied underA′, empirical ROCs are asymmetric and plastic. A dualprocess model predicted that the magnitude of the deviation would vary as a systematic function of the proportion of overall recognition accompanied by subjective remember reports for individual subjects. The predictions were confirmed using multiple regression on Monte Carlo and experimental data sets and were also shown to generalize to the double equal-threshold, single high-threshold [i.e., H — FA; (H — FA)/(1 — FA)], and the equal variance signal detection d9 corrections. The unequal variance signal detection model was also shown to mirror the data, but only under the post hoc assumption that every subject adopts a very similar remember criterion placement rule. The results demonstrate that the systematic failure of tightly constrained models of recognition constitutes valuable regression data for more complex models and simultaneously highlights why single-point measures of accuracy are unsuitable as summaries across conditions or groups. Furthermore, the results show that remember rates carry unique information regarding the underlying processes governing individual subject performance that cannot be gleaned from the overall hit and false alarm rates in isolation.     

The effects of mediated word lists on false recall and recognition

False memory effects were explored using unrelated list items (e.g., slope, reindeer, corn) that were related to mediators (e.g., ski, sleigh, flake) that all converged upon a single nonpresented critical item (CI; e.g., snow). In Experiment 1, participants completed either an initial recall test or arithmetic problems after study, followed by a final recognition test. Participants did not falsely recall CIs on the initial test; however, false alarms to CIs did occur in recognition, but only following an initial recall test. In Experiment 2, participants were instructed to guess the CI, followed by a recognition test. The results replicated Experiment 1, with an increase in CI false alarms. Experiment 3 controlled for item effects by replacing unrelated recognition items from Experiment 1 with both CIs and list items from nonpresented lists. Once again, CI false alarms were found when controlling for lexical characteristics, demonstrating that mediated false memory is not due simply to item differences.     

False recognition and word length: A reanalysis of Roediger,Watson, McDermott,and Gallo (2001) and some new data

Roediger, Watson, McDermott, and Gallo (2001) reported a multiple regression analysis of the variables that predicted rates of false recall and recognition across lists in the Deese/Roediger— McDermott paradigm. They concluded that false recollection was predictable from the backward associative strength of critical words and list words and the veridical recall level of list words, with no independent contribution of frequency, concreteness, or length of critical words. A reanalysis of their data shows that critical word length does contribute to false recognition when it is measured relative to the length of other words in the list. Relative word length in the form of an unsignedz-score has a larger correlation with false recognition than any of the variables used by Roediger et al. and is also independently predictive of false recognition. This relationship was confirmed by the results of two recognition experiments in which false positives were significantly less frequent for words of lengths that never occurred in a studied list than for words of lengths that did occur in the study list.     

The influence of linguistic labels on source‐monitoring decisions

Three studies explored the extent to which people use various object features, including linguistic label, shape, and category membership, to make decisions about the source of their memories. To isolate the influence of each feature, we used items that were related in the following four ways: as synonyms, as similar in shape and category membership, as homographs, or as unrelated. Participants read sentences and either saw or imagined a picture of the critical word's referent. Experiment 1 showed that participants committed more source errors for synonyms (e.g., rabbit and bunny) than for objects that were conceptually and perceptually similar (e.g., doughnut and bagel), which produced more errors than unrelated items. However, there was no effect of label, as people did not have more errors for homographs (e.g., baseball bat and flying bat) than unrelated items. In Experiment 2, presenting the critical word at study was not sufficient to lead people to use an item's label to make source decisions. However, Experiment 3 showed more source errors for homographs than unrelated pairs when semantic context was minimised at study, suggesting that people can use linguistic labels to make source decisions when other information is unavailable.     

Dissociative effects of phonological vs. semantic associates on recognition memory in the Deese/Roediger-McDermott paradigm

Using a variation of the Deese/Roediger–McDermott paradigm in four experiments, we examined hit rate, false alarm rate, and memory discriminability (d′) for critical items (e.g., sleep) after their semantic associates (e.g., dream, rest, and awake), phonological associates (e.g., bleep, sheep, and cheap) or unrelated items were studied. Replicating previous research (e.g., Neely & Tse, 2007), d′ was lower for critical items than for yoked associates in semantic lists. However, d′ was higher for critical items than for yoked associates in phonological lists, even when the same critical items were used for these two list types. The memory discriminability of critical items was enhanced by phonological lists via a larger increase in their hit rates than in their false alarm rates, relative to the same critical items in lists of unrelated words. These findings (a) could not be fully accounted for by the activation-based theories proposed in the false memory literature, and (b) may suggest that the memory discriminabilities of semantic and phonological lists are modulated by two distinct activation mechanisms.     

Concepts are not represented by conscious imagery

According to theories of grounded cognition, conceptual representation and perception share processing mechanisms. We investigated whether this overlap is due to conscious perceptual imagery. Participants filled out questionnaires to assess the vividness of their imagery (Questionnaire on Mental Imagery) and the extent to which their imagery was object oriented and spatially oriented (Object-Spatial Imagery Questionnaire), and they performed a mental rotation task. One week later, they performed a verbal property verification task. In this task, involvement of modality-specific systems is evidenced by the modality-switch effect, the finding that performance on a target trial (e.g., apple—green) is better after a same-modality trial (e.g., diamond—sparkle) than after a different-modality trial (e.g., airplane—noisy). Results showed a modality-switch effect, but there was no systematic relation between imagery scores and modality switch. We conclude that conscious mental imagery is not fundamental to conceptual representation.     

You'll change more than I will: Adults’ predictions about their own and others’ future preferences

It has been argued that adults underestimate the extent to which their preferences will change over time. We sought to determine whether such mispredictions are the result of a difficulty imagining that one's own current and future preferences may differ or whether it also characterizes our predictions about the future preferences of others. We used a perspective-taking task in which we asked young people how much they liked stereotypically young-person items (e.g., Top 40 music, adventure vacations) and stereotypically old-person items (e.g., jazz, playing bridge) now, and how much they would like them in the distant future (i.e., when they are 70 years old). Participants also made these same predictions for a generic same-age, same-sex peer. In a third condition, participants predicted how much a generic older (i.e., age 70) same-sex adult would like items from both categories today. Participants predicted less change between their own current and future preferences than between the current and future preferences of a peer. However, participants estimated that, compared to a current older adult today, their peer would like stereotypically young items more in the future and stereotypically old items less. The fact that peers’ distant-future estimated preferences were different from the ones they made for “current” older adults suggests that even though underestimation of change of preferences over time is attenuated when thinking about others, a bias still exists.     

Social contagion of memory

We report a new paradigm for studying false memories implanted by social influence, a process we call the social contagion of memory. A subject and confederate together saw six common household scenes (e.g., a kitchen) containing many objects, for either 15 or 60 sec. During a collaborative recall test, the 2 subjects each recalled six items from the scenes, but the confederate occasionally made mistakes by reporting items not from the scene. Some intrusions were highly consistent with the scene schema (e.g., a toaster) while others were less so (e.g., oven mitts). After a brief delay, the individual subject tried to recall as many items as possible from the six scenes. Recall of the erroneous items suggested by the confederate was greater than in a control condition (with no suggestion). Further, this social contagion effect was greater when the scenes were presented for less time (15 sec) and when the intruded item was more schema consistent (e.g., the toaster). As with other forms of social influence, false memories are contagious; one person’s memory can be infected by another person’s errors.     

When does giving voice or not matter? Procedural fairness effects as a function of closeness of reference points

The present study examined whether manipulating the closeness of reference points can provide further insights into explaining why people care so much about receiving voice (i.e., the opportunity to express one’s opinion with respect to allocation decisions). Participants read a scenario portraying a situation where they had always been a member of the relevant team (i.e., distant referent point condition) or where they had just become a member of the relevant team (i.e., close referent point condition). Thereafter, they were either told that they would receive voice or no voice with respect to the issue of distributing a financial bonus. The results showed that people cared more about voice when they were placed in the distant referent condition rather than in the close referent condition. This effect was strongest on participants’ positive emotions (i.e., being positive when receiving voice vs. receiving no voice) than on their negative emotions. The findings are discussed in light of procedural fairness, counterfactual thinking, and emotion literature.