Beneficial Effect of Pictures on False Memory in the DRMRS Procedure

Using the Deese-Roediger-McDermott-Read-Solso (DRMRS) procedure in which list items are shown that are semantically related to a central theme that is not presented, undergraduates (N?=?61) studied either short or long lists in the form of auditory words alone, pictures alone, or pictures accompanied by auditory words. Correct recall and correct recognition scores were similar in all three conditions. However, false memory (reporting the non-presented central theme) was reduced with pictures alone compared to words alone for the recall task, and for the recognition task with short lists. Confidence was higher for correct recall and correct recognition than for false recall and false recognition, but people who were higher or lower in confidence did not differ on any memory measure. Theoretical and practical implications of these results are discussed.     

Episodic encoding and recognition of pictures and words: role of the human medial temporal lobes

In the present PET study, we examined brain activity related to processing of pictures and printed words in episodic memory. Our goal was to determine how the perceptual format of objects (verbal versus pictorial) is reflected in the neural organization of episodic memory for common objects. We investigated this issue in relation to encoding and recognition with a particular focus on medial temporal-lobe (MTL) structures. At encoding, participants saw pictures of objects or their written names and were asked to make semantic judgments. At recognition, participants made yes-no recognition judgments in four different conditions. In two conditions, target items were pictures of objects; these objects had originally been encoded either in picture or in word format. In two other conditions, target items were words; they also denoted objects originally encoded either as pictures or as words. Our data show that right MTL structures are differentially involved in picture processing during encoding and recognition. A posterior MTL region showed higher activation in response to the presentation of pictures than of words across all conditions. During encoding, this region may be involved in setting up a representation of the perceptual information that comprises the picture. At recognition, it may play a role in guiding retrieval processes based on the perceptual input, i.e. the retrieval cue. Another more anterior right MTL region was found to be differentially involved in recognition of objects that had been encoded as pictures, irrespective of whether the retrieval cue provided was pictorial or verbal in nature; this region may be involved in accessing stored pictorial representations. Our results suggest that left MTL structures contribute to picture processing only during encoding. Some regions in the left MTL showed an involvement in semantic encoding that was picture specific; others showed a task-specific involvement across pictures and words. Together, our results provide evidence that the involvement of some but not all MTL regions in episodic encoding and recognition is format specific.     

Eye movement indices of memory reveal re-processing of visual information: Evidence from Chinese characters

ABSTRACT

This study examined the nature of the memory effect revealed in eye movements. Chinese characters were processed visually, phonologically or semantically during the study phase. The proportion of viewing time during the subsequent recognition test was compared between characters associated with different types of encoding. To eliminate the influence of response selection on eye movements, participants were asked to select the unstudied character and make the selection after the viewing period ended. Results showed that the proportion of viewing time in the recognition test was larger for visually encoded characters than it was for semantically (Experiment 1) and phonologically encoded (Experiment 3) characters, even after the participants had presumably made the decision. Moreover, there was no significant difference in the proportion of viewing time between phonologically and semantically encoded characters (Experiment 2). These findings suggest that the viewing time change in eye movements during the recognition test is an obligatory consequence of re-processing the visual information encoded during the study phase.     

Exploring the role of attention during memory retrieval: Effects of semantic encoding and divided attention

Research on attention and memory suggests that semantic encoding leads to retrieval that is highly susceptible to divided attention. Three experiments tested this proposition and showed that dividing attention did not selectively affect semantically encoded items. Participants encoded a list of words in one of two ways: semantically or phonetically. Later, memory was assessed using either a standard recognition test (Experiment 1) or a rhyme recognition test (Experiments 2 and 3). The participants took the memory test either alone (full attention) or while simultaneously performing a secondary task (divided attention). Recognition accuracy was reduced by divided attention on both recognition tests, and semantically and phonetically encoded words were equally affected.     

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。     

Tactile Short-term Memory Revisited

In spite of a large body of empirical research demonstrating the importance of multisensory integration in cognition, there is still little research about multimodal encoding and maintenance effects in working memory. In this study we investigated multimodal encoding in working memory by means of an immediate serial recall task with different modality and format conditions. In a first non-verbal condition participants were presented with sequences of non-verbal inputs representing familiar (concrete) objects, either in visual, auditory or audio-visual formats. In a second verbal condition participants were presented with written, spoken, or bimodally presented words denoting the same objects represented by pictures or sounds in the non-verbal condition. The effects of articulatory suppression were assessed in both conditions. We found a bimodal superiority effect on memory span with non-verbal material, and a larger span with auditory (or bimodal) versus visual presentation with verbal material, with a significant effect of articulatory suppression in the two conditions.     

Cross-modality translations improve recognition by reducing false alarms

Conway and Gathercole [(1990). Writing and long-term memory: Evidence for a “translation” hypothesis. The Quarterly Journal of Experimental Psychology, 42, 513–527] proposed a translation account to explain why certain types of encoding produce benefits in memory: Switching modalities from what is presented to what is encoded enhances item distinctiveness. We investigated this hypothesis in a recognition experiment in which the presentation modality of a study list (visual vs. auditory) and the encoding activity (speaking vs. typing vs. passive encoding) were manipulated between-subjects. Manipulating encoding activity between-subjects ruled out any potential influence of the relationally distinct processing that can occur in a within-subject manipulation (in which all previous translation effects have been demonstrated). We found no overall difference in memory for words presented auditorily vs. visually nor for visual vs. auditory encoding, but critically presentation modality and encoding activity did interact. Translating from one modality to another – particularly from auditory presentation to visual encoding (typing) – led to the best memory discrimination. This was largely because of reduced false alarms, not increased hits, consistent with the distinctiveness heuristic.     

Flexibility of working memory encoding in a sentence–picture–sound verification task

Dual-process accounts of working memory have suggested distinct encoding processes for verbal and visual information in working memory, but encoding for nonspeech sounds (e.g., tones) is not well understood. This experiment modified the sentence–picture verification task to include nonspeech sounds with a complete factorial examination of all possible stimulus pairings. Participants studied simple stimuli–pictures, sentences, or sounds–and encoded the stimuli verbally, as visual images, or as auditory images. Participants then compared their encoded representations to verification stimuli–again pictures, sentences, or sounds–in a two-choice reaction time task. With some caveats, the encoding strategy appeared to be as important or more important than the external format of the initial stimulus in determining the speed of verification decisions. Findings suggested that: (1) auditory imagery may be distinct from verbal and visuospatial processing in working memory; (2) visual perception but not visual imagery may automatically activate concurrent verbal codes; and (3) the effects of hearing a sound may linger for some time despite recoding in working memory. We discuss the role of auditory imagery in dual-process theories of working memory.     

Semantic and visual relatedness of distractors impairs episodic retrieval of pictures in a divided attention paradigm

We used a divided attention (DA) paradigm to infer the representational codes needed to support episodic retrieval of pictures, by measuring susceptibility to memory interference from different distracting tasks. Participants made recognition memory decisions to semantically categorized sets of pictures while simultaneously making size judgments to a set of visually-presented distractor pictures. Recognition accuracy was worse and response times were slower under DA conditions relative to full attention (FA), regardless of semantic relatedness of distractors to targets (Experiment 1). Similarly, we found no differential memory interference under DA relative to FA when distractor pictures were either visually (but not semantically), semantically (but not visually), or unrelated to the targets (Experiment 2). In Experiment 3, memory interference was significantly larger under DA at retrieval when distractors were both semantically and visually similar to the targets. Findings suggest episodic memory for pictures requires access to either visually- or semantically-based representations for optimal performance.     

Mental scanning of sonifications reveals flexible encoding of nonspeech sounds and a universal per-item scanning cost

A mental scanning paradigm was used to examine the representation of nonspeech sounds in working memory. Participants encoded sonifications – nonspeech auditory representations of quantitative data – as either verbal lists, visuospatial images, or auditory images. The number of tones and overall frequency changes in the sonifications were also manipulated to allow for different hypothesized patterns of reaction times across encoding strategies. Mental scanning times revealed different patterns of reaction times across encoding strategies, despite the fact that all internal representations were constructed from the same nonspeech sound stimuli. Scanning times for the verbal encoding strategy increased linearly as the number of items in the verbal representation increased. Scanning times for the visuospatial encoding strategy were generally slower and increased as the metric distance (derived metaphorically from frequency change) in the mental image increased. Scanning times for the auditory imagery strategy were faster and closest to the veridical durations of the original stimuli. Interestingly, the number of items traversed in scanning a representation significantly affected scanning times across all encoding strategies. Results suggested that nonspeech sounds can be flexibly represented, and that a universal per-item scanning cost persisted across encoding strategies. Implications for cognitive theory, the mental scanning paradigm, and practical applications are discussed.     

Reinstatement of odour context cues veridical memories but not false memories

ABSTRACT

The sense of smell has made a recent return to the forefront of research on episodic memory. Odour context cues can reactivate recently encoded memories during sleep-dependent memory consolidation [e.g., Rasch, B., Buchel, C., Gais, S., & Born, J. (2007). Odor cues during slow-wave sleep prompt declarative memory consolidation. Science, 315, 1426–1429], and reinstating the odour experienced during encoding at test results in superior recall and recognition [e.g., Isarida, T., Sakai, T., Kubota, T., Koga, M., Katayama, Y., & Isarida, T. K. (2014). Odor-context effects in free recall after a short retention interval: A new methodology for controlling adaptation. Memory & Cognition, 42, 421–433]. However, whether the impact of odour cues is restricted to the specific memories studied in the presence of the odour, or whether reinstating the odour also cues unstudied memories that are semantically related to the studied memories (i.e., false memories) is unknown. We used the Deese-Roediger-McDermott false memory paradigm to quantify the impact of odour cues on both veridical memory and false memory. Reinstating the odour presented during the study of the DRM word lists at the test phase resulted in better free recall of the studied words, but had no statistically significant impact on the number of false memories produced. We argue that odour cues influence recall of the memories they co-occurred with during study but potentially not semantically related memories.     

Speaker information affects false recognition of unstudied lexical-semantic associates

Recognition of and memory for a spoken word can be facilitated by a prior presentation of that word spoken by the same talker. However, it is less clear whether this speaker congruency advantage generalizes to facilitate recognition of unheard related words. The present investigation employed a false memory paradigm to examine whether information about a speaker’s identity in items heard by listeners could influence the recognition of novel items (critical intruders) phonologically or semantically related to the studied items. In Experiment 1, false recognition of semantically associated critical intruders was sensitive to speaker information, though only when subjects attended to talker identity during encoding. Results from Experiment 2 also provide some evidence that talker information affects the false recognition of critical intruders. Taken together, the present findings indicate that indexical information is able to contact the lexical-semantic network to affect the processing of unheard words.     

Get the gist? The effects of processing depth on false recognition in short-term and long-term memory

Gist-based processing has been proposed to account for robust false memories in the converging-associates task. The deep-encoding processes known to enhance verbatim memory also strengthen gist memory and increase distortions of long-term memory (LTM). Recent research has demonstrated that compelling false memory illusions are relatively delay-invariant, also occurring under canonical short-term memory (STM) conditions. To investigate the contributions of gist to false memory at short and long delays, processing depth was manipulated as participants encoded lists of four semantically related words and were probed immediately, following a filled 3- to 4-s retention interval, or approximately 20 min later, in a surprise recognition test. In two experiments, the encoding manipulation dissociated STM and LTM on the frequency, but not the phenomenology, of false memory. Deep encoding at STM increases false recognition rates at LTM, but confidence ratings and remember/know judgments are similar across delays and do not differ as a function of processing depth. These results suggest that some shared and some unique processes underlie false memory illusions at short and long delays.     

Role of stimulus modality in rating ordinary and derived word strings.

Four types of word strings were presented either visually or auditorily and rated for grammaticality and meaningfulness. The string types were normal sentences, syntactically deviant strings, semantically deviant strings, and strings both syntactically and semantically deviant. Results for the auditory mode conform to expectations based upon the linguistic competence of the native speaker but results for the visual mode do not. The results are discussed in terms of the inferiority of visual over auditory short-term memory for verbal information and attentional strategies.     

Source memory that encoding was self-referential: the influence of stimulus characteristics

Decades of research suggest that encoding information with respect to the self improves memory (self-reference effect, SRE) for items (item SRE). The current study focused on how processing information in reference to the self affects source memory for whether an item was self-referentially processed (a source SRE). Participants self-referentially or non-self-referentially encoded words (Experiment 1) or pictures (Experiment 2) that varied in valence (positive, negative, neutral). Relative to non-self-referential processing, self-referential processing enhanced item recognition for all stimulus types (an item SRE), but it only enhanced source memory for positive words (a source SRE). In fact, source memory for negative and neutral pictures was worse for items processed self-referentially than non-self-referentially. Together, the results suggest that item SRE and source SRE (e.g., remembering an item was encoded self-referentially) are not necessarily the same across stimulus types (e.g., words, pictures; positive, negative). While an item SRE may depend on the overall likelihood the item generates any association, the enhancing effects of self-referential processing on source memory for self-referential encoding may depend on how embedded a stimulus becomes in one’s self-schema, and that depends, in part, on the stimulus’ valence and format. Self-relevance ratings during encoding provide converging evidence for this interpretation.     

Modality effect in false recognition: evidence from Chinese characters

Using the Deese/Roediger‐McDermott (DRM) false memory method, Smith and Hunt ( 1998 ) first reported the modality effect on false memory and showed that false recall from DRM lists was lower following visual study than following auditory study, which led to numerous studies on the mechanism of modality effect on false memory and provided many competing explanations. In the present experiment, the authors tested the modality effect in false recognition by using a blocked presentation condition and a random presentation condition. The present experiment found a modality effect different from the results of the previous research; namely, false recognition was shown to be greater following visual study than following auditory study, especially in the blocked presentation condition rather than in the random presentation condition. The authors argued that this reversed modality effect may be due to different encoding and processing characteristics between Chinese characters and English words. Compared with English words, visual graphemes of critical lures in Chinese lists are likely to be activated and encoded in participants' minds, thus it is more difficult for participants to discriminate later inner graphemes from those items presented in visual modality. Hence visual presentation could lead to more false recognition than auditory presentation in Chinese lists. The results in the present experiment demonstrated that semantic activation occurring during the encoding and retrieve phases played an important role in modality effect in false recognition, and our findings might be explained by the activation‐monitoring account.     

The effects of auditory shadowing on recognition of information received visually

When Ss attend to one auditory message, they have no permanent memory for a second auditory message received simultaneously. Generally, it has been argued that a similar effect would occur crossmodally. This hypothesis was tested in the present experiment for messages presented to visual and auditory modalities. All Ss were tested for recognition of information presented either while shadowing or while hearing but not shadowing a passage of prose presented to one ear. One group heard a list of concrete nouns in their other ear. Three other groups received (1) printed words. (2) pictures of objects easily labeled, or (3) pictures of objects difficult to label. The shadowing task produced a decrement m recognition scores for the first three groups but not for the group receiving pictures of objects difficult to label. Further, the shadowing task interfered more with information received auditorily than with any form of visual information. These results suggest that information received visually is stored in a long-term modality-specific memory that may operate independently of the auditory modality.     

Distinctive encoding reduces the Jacoby—Whitehouse illusion

We investigated the influence of distinctive encoding on the Jacoby and Whitehouse (1989) illusion. Subjects studied visually presented words that were associated with either an auditory presentation of the same word (nondistinctive encoding) or a picture of the object (distinctive encoding). In both conditions, words were visually presented on the recognition test, and half were preceded by brief repetition primes. Priming test items increased hits and false alarms in the auditory condition, demonstrating the Jacoby-Whitehouse illusion. This illusion was reduced in the picture condition. In order to test whether this distinctiveness effect was caused by a recollection-based response strategy (i.e., the distinctiveness heuristic), we minimized recollection-based responding by having subjects make speeded recognition decisions. Contrary to the distinctiveness heuristic hypothesis, speeded responding did not eliminate the distinctiveness effect on the Jacoby-Whitehouse illusion. Picture encoding may reduce this illusion via a shift in preretrieval orientation, as opposed to a postretrieval editing process.     

The low-frequency encoding disadvantage: Word frequency affects processing demands

Low-frequency words produce more hits and fewer false alarms than high-frequency words in a recognition task. The low-frequency hit rate advantage has sometimes been attributed to processes that operate during the recognition test (e.g., L. M. Reder et al., 2000). When tasks other than recognition, such as recall, cued recall, or associative recognition, are used, the effects seem to contradict a low-frequency advantage in memory. Four experiments are presented to support the claim that in addition to the advantage of low-frequency words at retrieval, there is a low-frequency disadvantage during encoding. That is, low-frequency words require more processing resources to be encoded episodically than high-frequency words. Under encoding conditions in which processing resources are limited, low-frequency words show a larger decrement in recognition than high-frequency words. Also, studying items (pictures and words of varying frequencies) along with low-frequency words reduces performance for those stimuli.     

Serial position-dependent false memory effects*

ABSTRACT

Evidence for false recognition within seconds of encoding suggests that semantic-associative influences are not restricted to long-term memory, consistent with unitary memory accounts but contrary to dual store models. The present study sought further relevant evidence using a modified free recall converging associates task where participants studied 12-item lists composed of 3 semantically distinct quartets (sublists) related to a separate, non-presented theme word (i.e., words 1–4/theme1, 5–8/theme2, and 9–12/theme3). This list construction permits assessment of false recall errors from each sublist, and, particularly, the primacy and recency sublists that have been linked to long- and short-term memory stores. Experiment 1 tested immediate free recall for items. Associative false memories were evident from all sublists, however, significantly less so from the recent sublist, which also showed the highest levels of veridical memory. By inserting a brief (3?s) distractor prior to recall, Experiment 2 selectively reduced veridical memory and increased false memory for the recent sublist while leaving the primacy sublist unaffected. These recall results converge with prior evidence indicating the immediacy of false recognition, and can be understood within a unitary framework where the differential availability of verbatim features and gist-based cues affect memory for primacy and recency sublists.