Recognition instructions and recognition practice can alter the confidence--response time relationship

Three face-recognition experiments examined how instructions for a recognition test (e.g., emphasize speed or emphasize accuracy) can impact the confidence-response time relationship for episodic memory reports. In all 3 experiments, the confidence-response time correlation was smaller when participants were told to speed up their responding rate, which suggests that participants in these conditions relied less on the artificially compressed response times in forming their confidence judgments than they would under "normal" circumstances. Also, recognition practice before the final memory test eliminated the effect of the recognition instruction manipulation. These results support J. S. Shaw's (1996) suggestion that witnesses rely in part on the fluency of their memory reports when generating confidence judgments, and these findings have important implications for understanding the relationships among witness confidence, accuracy, and response time.     

Preserved metamemorial ability in patients with mild Alzheimer's disease: shifting response bias

Patients with mild Alzheimer's disease (AD) display a greater tendency to endorse unstudied items as "old" on memory tests than healthy older adults. This liberal response bias may result in mistaken beliefs about the completion of common tasks. This research attempted to determine whether it was possible to shift the response bias of mild AD patients to be more conservative on a recognition memory test through behavioral intervention. Patients with mild AD and matched controls were evaluated with two almost identical paradigms, separated by about one week. For each session, 30 words were studied and 60 words (half studied, half novel) were shown at test. During one session participants were told that 30% of words were old, and at the other session that 70% were old. We found that both groups were able to shift their response bias between the two conditions. That patients with mild AD were able to successfully shift their response bias demonstrates that--despite their overall liberal response bias and poor memory relative to controls--one component of metamemorial ability is preserved in patients with mild AD.     

来源检测对表象引发的错误记忆的影响

采用“学习-再认”模式,考察来源检测对表象引发的错误记忆的影响。结果发现,在再认任务中,正确再认观察项目与想象项目的反应时差异不显著,但在源检测中,正确再认观察项目显著快于正确再认想象项目; 再认时与源检测时的错误再认率差异不显著,但对想象项目的错误再认率显著高于对观察项目。这表明,表象会导致错误记忆发生,提高来源检测操纵并不能够削弱表象引发的错误记忆。根据研究结果提出“表象激活混淆假设”,认为人们虽然使用表象的信息表征方式,却无法获取与之联系的激活路径,容易混淆表象激活的来源。表象激活混淆是表象引发错误记忆的机制。     

Recognition memory performance as a function of reported subjective awareness

Three experiments introduced a recognition memory paradigm designed to investigate reported subjective awareness during retrieval. At study, in Experiments 1A and 2, words were either generated or read (generation), while modality of presentation (auditory versus visual) was manipulated in Experiment 1B. Word pairs (old/new or new/new) were presented during test trials, and participants indicated if they contained an old word by responding "remember", "know" or "new" in Experiments 1A and 1B, and by responding "strong no", "weak no", "weak yes", or "strong yes" in Experiment 2. Participants were then required to decide which of the 2 words was old. We demonstrated that the proportion measures used in the Remember Know paradigm substantially underestimated the influence of generation on familiarity resulting in an artificial dissociation between indices of knowing (familiarity) and remembering (recollection). We also found a qualitatively different pattern of forced-choice recognition performance as a function of claimed awareness.     

No source memory for unrecognized items when implicit feedback is avoided

In a recent empirical study, Starns, Hicks, Brown, and Martin (Memory & Cognition, 36, 1–8 2008) collected source judgments for old items that participants had claimed to be new and found residual source discriminability depending on the old-new response bias. The authors interpreted their finding as evidence in favor of the bivariate signal-detection model, but against the two-high-threshold model of item/source memory. According to the latter, new responses only follow from the state of old-new uncertainty for which no source discrimination is possible, and the probability of entering this state is independent of the old-new response bias. However, when missed old items were presented for source discrimination, the participants could infer that the items had been previously studied. To test whether this implicit feedback led to second retrieval attempts and thus to source memory for presumably unrecognized items, we replicated Starns et al.’s (Memory & Cognition, 36, 1–8 2008) finding and compared their procedure to a procedure without such feedback. Our results challenge the conclusion to abandon discrete processing in source memory; source memory for unrecognized items is probably an artifact of the procedure, by which implicit feedback prompts participants to reconsider their recognition judgment when asked to rate the source of old items in the absence of item memory.     

Contribution of perceptual fluency to recognition judgments.

Following a shallow (count vowels) or deep (read) study task, old and new words were tested for both fluency of perception and recognition memory. Subjects first identified a test word as it came gradually into view and then judged it as old or new. Old words were identified faster than new words, indicating implicit, perceptual memory for old words. Independently of this effect, words judged old were identified faster than words judged new, especially after shallow study. Eight experiments examined the possible causal relationship between perceptual fluency and recognition judgements. Experiments 1 to 4 showed that fast identifications per se do not promote old judgments. Accelerating the identification of test items by semantically priming them or making them come more quickly into view did not affect recognition judgments. Experiment 5 showed that the usual association of fast identifications with old judgments is not an artifact of item selection because the association disappeared when the identifications and judgements were segregated into different phases of the test task. Experiments 6 and 7 showed tha the likelihood of old judgments increases directly with the pretested perceptibility of test words, but only after shallow study. Experiment 8 showed that the dependency of recognition judgments on perceptual fluency continues to hold when the requirement to identify the words before judging them is eliminated. We conclude that fluency of perception contributes to recognition judgments, but only when the fluency is produced naturally (e.g., through perceptual memory) and explicit memory is minimal.     

Effects of talker, rate, and amplitude variation on recognition memory for spoken words

This study investigated the encoding of the surface form of spoken words using a continuous recognition memory task. The purpose was to compare and contrast three sources of stimulus variability--talker, speaking rate, and overall amplitude--to determine the extent to which each source of variability is retained in episodic memory. In Experiment 1, listeners judged whether each word in a list of spoken words was "old" (had occurred previously in the list) or "new." Listeners were more accurate at recognizing a word as old if it was repeated by the same talker and at the same speaking rate; however, there was no recognition advantage for words repeated at the same overall amplitude. In Experiment 2, listeners were first asked to judge whether each word was old or new, as before, and then they had to explicitly judge whether it was repeated by the same talker, at the same rate, or at the same amplitude. On the first task, listeners again showed an advantage in recognition memory for words repeated by the same talker and at same speaking rate, but no advantage occurred for the amplitude condition. However, in all three conditions, listeners were able to explicitly detect whether an old word was repeated by the same talker, at the same rate, or at the same amplitude. These data suggest that although information about all three properties of spoken words is encoded and retained in memory, each source of stimulus variation differs in the extent to which it affects episodic memory for spoken words.     

Are emotionally charged lures immune to false memory?

Using the Deese-Roediger-McDermott task and E. Tulving's (1985) remember-know judgments for recognition memory, the authors explored whether emotional words can show the false memory effect. Participants studied lists containing nonemotional, orthographic associates (e.g., cape, tape, ripe; part, perk, dark) of either emotional (e.g., rape) or nonemotional (e.g., park) critical lures. This setup produced significant false "remembering" of emotional lures, even though initially no emotional words appeared at study. When 3 emotional nonlure words appeared at study, emotional-lure false recognition more than doubled. However, when these 3 study words also appeared on the recognition test, false memory for the emotional lures was reduced. Across experiments, participants misremembered nonemotional lures more often than they did emotional lures, but they were more likely to rate emotional lures as "remembered," once they had been recognized as "old." The authors discuss findings in light of J. J. Freyd and D. H. Gleave's (1996) criticisms of this task.     

Memory with and without awareness: performance and electrophysiological evidence of savings.

Event-related potentials (ERPs) recorded on the scalp were shown to be sensitive indicators of the strength of a memory trace on both implicit and explicit tests of memory. In explicit recognition tests, the amplitude of a positive potential identified as P300 was larger for "old" than for "new" words regardless of whether the subject categorized the items correctly. This effect, however, was statistically reliable only when the recognition memory (d') was relatively high. In contrast to ERPs, the reaction times in explicit recognition were sensitive to accuracy but not to repetition. In implicit tests, lexical decisions to repeated words were faster than to newly presented words. The magnitude of the repetition effect varied neither with elapsed time since the last repetition nor with the number of previous repetitions. In contrast, the P300 elicited by the same words were sensitive to both lag and recency of repetition, suggesting that they were influenced by the episodic memory strength of the items.     

Associative false recognition occurs without strategic criterion shifts

In the DRM (Deese/Roediger and McDermott) false memory paradigm, subjects studied lists of words associated with nonpresented critical words. They were tested in one of four instructional conditions. In a standard condition, subjects were not warned about the DRM Effect. In three other conditions, they were told to avoid false recognition of critical words. One group was warned before study of the lists (affecting encoding and retrieval processes), and two groups were warned after study (affecting only retrieval processes). Replicating prior work, the warning before study considerably reduced false recognition. The warning after study also reduced false recognition, but only when critical items had never been studied; when critical items were studied in half the lists so that subjects had to monitor memory for their presence or absence, the warning after study had little effect on false recognition. Because warned subjects were trying to avoid false recognition, the high levels of false recognition in the latter condition cannot be due to strategically guessing that critical test items were studied. False memories in the DRM paradigm are not caused by such liberal criterion shifts.     

Effects of study task on the neural correlates of source encoding

The present study investigated whether the neural correlates of source memory vary according to study task. Subjects studied visually presented words in one of two background contexts. In each test, subjects made old/new recognition and source memory judgments. In one study test cycle, study words were subjected to animacy judgments, whereas in another cycle the study task required syllable judgments. Functional magnetic resonance imaging (fMRI) was employed to contrast the neural activity elicited by study words that attracted accurate source judgments on the later memory test, as opposed to words for which source judgments were incorrect or for which source information was unavailable. In both tasks, relative to words for which source memory failed, study words that were later assigned to the correct source elicited enhanced activity in ventral extrastriate cortex. In addition to these common effects of subsequent source memory, additional effects were observed that were selective for each study task. The present findings add weight to the proposal that neural activity supporting successful episodic memory encoding is a reflection of both the online processing engaged by an episode as it is experienced, and the demands imposed by the later retrieval task.     

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.     

False recognition and perception without awareness

Jacoby and Whitehouse (1989) demonstrated that the probability of calling new test words "old" (i.e., false recognition) is biased by context words. When context words were briefly exposed and subjects were not informed of their presence, new words were called "old" more often if the context and test words were identical than if the context and test words were different. When the context words were presented at longer exposure durations and subjects were informed of their presence, the opposite pattern of results occurred. In Experiment 1, we replicated the critical qualitative difference across conditions reported by Jacoby and Whitehouse. In addition, the combined results of Experiments 2 and 3 demonstrated that the exposure duration of the context words, and not the instructions to the subjects, is the primary factor determining which pattern of false recognition occurs. However, in contrast with the findings of Jacoby and Whitehouse, both patterns of false recognition were associated with significant recognition memory for the context words. The latter finding presents problems for any interpretation of false recognition, which implies that the briefly exposed context words are perceived without awareness.     

Intact emotion-induced recognition bias in neuropsychological patients with executive control deficits

In recognition memory tasks, emotionally negative words are judged more often as "old" relative to emotionally neutral words, suggesting a shift in response bias. We wondered whether this bias shift was due to the flexible regulation of executive control during memory retrieval. To address this question, we investigated individuals with high variability in executive control functions. As expected, we observed that emotional word meaning did indeed have a strong influence on the bias toward responding "old," independent of recognition accuracy and overall response bias. However, these effects were uncorrelated with executive control, as measured by the Trail Making Test, and were fully intact, even in a sample of hospitalized neurological patients with severe executive dysfunctions, some of whom had marked damage in fronto-thalamo-striatal networks. Having concluded that the emotion-induced bias must develop on different grounds, we went on to discuss alternative explanations.     

Children's memory for new songs: integration or independent storage of words and tunes?

The present study investigated how young children encode a song in memory, specifically, whether they integrate or store independently in memory the text and the tune of a song. Preschool children and, for purposes of comparison, adults, each participated in two test sessions: in one they were presented three novel tunes each with rhyming text and in the other they heard the same three tunes but with nonrhyming text. Following this familiarization phase they received a recognition test. On each trial, they heard one of five types of songs; the original song, a completely new song (new words, new tune), a mismatch of the tune of one song with the words of another, old words with a new tune, and new words with an old tune. The subject's task was to decide if each test song was "exactly the same," "somewhat the same," or "not at all the same" as any one of the three original songs. At both ages the proportion of "same" responses was significantly greater for the original than mismatch songs, indicating that listeners were more likely to remember the exact pairing of text and tune than to retain the components independently. However, integration was significantly greater for adults than children. At both ages, for songs judged as similar to the original songs, the words more often than the tune proved to be the most salient feature, particularly for children. There were no significant effects of rhyme on performance at either age. The results are discussed in terms of Serafine, Crowder, and Repp's (1984) hypothesis that one integrates the tune and text of a song in memory, rather than storing components separately.     

When repeating aloud enhances episodic memory for spoken words: interactions between production- and perception-derived variability

We demonstrate that the phonetic detail of an original speaker’s pronunciation for a word can be detected with a memory measure even when a participant listens to and then repeats that word aloud (production). At study, native English participants heard English words pronounced by a native speaker of American-English or by a Chinese national. For half of the words they listened. For the others, they produced it. In both recall and old/new recognition tests in Experiment 1, production improved performance relative to listening alone. Effects of accent were present only in recognition and only in interaction with production. In Experiment 2, a source-monitoring recognition test where participants identified whether the speaker of a word changed from study to test, effects of accent and production were additive indicating that hearing an unfamiliar accent increased memory irrespective of production. An exemplar account including both production- as well as perception-derived experience describes the outcome.     

编码任务对来源记忆的影响:一项事件相关电位研究

本研究采用ERPs技术,探讨编码任务对来源记忆的影响及其神经机制。在学习阶段,被试进行两种编码操作：匹配判断任务和大小判断任务;在测验阶段,让被试进行来源判断任务。行为结果发现：在编码阶段,匹配判断任务比大小判断任务需要更长的时间;在测验阶段,匹配判断任务在“项目旧/背景旧”和“部分旧”条件的正确率显著高于大小判断任务,匹配判断任务在“项目旧/背景旧”条件的反应时显著短于大小判断任务。测验阶段ERPs结果发现：两种编码任务的新旧效应在200~700ms均有较广泛的头皮分布,而在700~1100ms呈前额皮层最大化分布;匹配判断任务的新旧效应比大小判断任务更大,表现在600~700ms的FPz电极以及700~800ms的Pz、P4电极。由此可见,在来源记忆中,编码任务影响来源记忆,主要表现在后部顶区位置;晚期前额皮层新旧效应不受任务难度因素的影响。     

Declarativeand nondeclarativememory in opposition:When priorevents influence amnesicpatients morethan normal subjects

Amnesic patients and normal subjects read the names of nonfamous persons. Then, after being told that all the names were nonfamous, subjects judged the fame of names on a mixed list of new famous names, old nonfamous names, and new nonfamous names. Finally, they took a recognition memory test involving old and new nonfamous names. In this way, declarative (explicit) memory and nondeclarative (implicit) memory were placed in opposition. That is, recollection that a name had been recently presented (and was therefore nonfamous) opposed the focilitatory effect by which prior presentation ordinarily increases the tendency to judge that name as famous. Normal subjects exhibited good recognition memory and no fame-judgment effect—that is, no difference in fame judgments for new and old nonfamous names. By contrast, for the amnesic patients recognition memory was poor, but astrong fame-judgment effect occurred—that is, amnesic patients judged old nonfamousnames as famous. The results provide additional evidence that the fame-judgment effect is supported fully by nondeclarative (implicit) memory and is independent of the limbic/diencephalicbrain structures damaged in amnesia.     

Conscious and unconscious discriminations between true and false memories

When subjects give higher confidence or memory ratings to a test word in a recognition test, do they simply raise their criterion without making better discrimination, or do they raise both criterion and true discrimination between the studied words (SW) and the lures? Given that previous studies found subjects’ false alarm responses to lures slower than to SW, and recognition latency inversely correlated with the confidence rating, can the latency difference between the lures and SW be accounted for by confidence or memory ratings? The present results showed that when subjects gave higher confidence or memory ratings, both their bias and sensitivity were raised, indicating that they could consciously distinguish the lures from the SW. However, a latency difference between true and false recognitions persisted after confidence and memory ratings were held constant, suggesting an unconscious source of discrimination between the two types of memory.     

Effects of cell-phone and text-message distractions on true and false recognition

This study examined the effects of electronic communication distractions, including cell-phone and texting demands, on true and false recognition, specifically semantically related words presented and not presented on a computer screen. Participants were presented with 24 Deese-Roediger-McDermott (DRM) lists while manipulating the concurrent presence or absence of cell-phone and text-message distractions during study. In the DRM paradigm, participants study lists of semantically related words (e.g., mother, crib, and diaper) linked to a non-presented critical lure (e.g., baby). After studying the lists of words, participants are then requested to recall or recognize previously presented words. Participants often not only demonstrate high remembrance for presented words (true memory: crib), but also recollection for non-presented words (false memory: baby). In the present study, true memory was highest when participants were not presented with any distraction tasks during study of DRM words, but poorer when they were required to complete a cell-phone conversation or text-message task during study. False recognition measures did not statistically vary across distraction conditions. Signal detection analyses showed that participants better discriminated true targets (list items presented during study) from true target controls (items presented during study only) when cell-phone or text-message distractions were absent than when they were present. Response bias did not vary significantly across distraction conditions, as there were no differences in the likelihood that a participant would claim an item as "old" (previously presented) rather than "new" (not previously presented). Results of this study are examined with respect to both activation monitoring and fuzzy trace theories.