Active versus passive maintenance of visual nonverbal memory

Forgetting over the short term has challenged researchers for more than a century, largely because of the difficulty of controlling what goes on within the memory retention interval. But the “recent-negative-probe” procedure offers a valuable paradigm, by examining the influences of (presumably) unattended memoranda from prior trials. Here we used a recent-probe task to investigate forgetting for visual nonverbal short-term memory. The target stimuli (two visually presented abstract shapes) on a trial were followed after a retention interval by a probe, and participants indicated whether the probe matched one of the target items. Proactive interference, and hence memory for old trial probes, was observed, whereby participants were slowed in rejecting a nonmatching probe on the current trial that nevertheless matched a target item on the previous trial (a recent-negative probe). The attraction of the paradigm is that, by uncovering proactive influences of past-trial probe stimuli, it can be argued that active maintenance in memory of those probes is unlikely. In two experiments, we recorded such proactive interference of prior-trial items over a range of interstimulus (ISI) and intertrial (ITI) intervals (between 1 and 6 s, respectively). Consistent with a proposed two-process memory conception (the active–passive memory model, or APM), actively maintained memories on current trials decayed, but passively “maintained,” or unattended, visual memories of stimuli on past trials did not.     

Explicit memory for unattended words: the importance of being in the "no"

Recognition tests in which participants indicate whether they recognize items using binary yes/no response options have typically yielded "yes" responses at equal rates for unattended old items and new items. Because most responses to unattended stimuli in such tests are "no" responses, we reasoned that a closer examination of "no" responses might reveal memory for unattended items. We modified a classic paradigm to allow participants to indicate high and low levels of confidence in their responses. As in earlier studies, the overall proportion of "yes" responses did not differ between unattended old items and new items. However, there was a crossover effect in the "no" responses: More high-confidence "no" responses were given for new items than for unattended old items, whereas more low-confidence "no" responses were given for unattended old items than for new items. These results indicate explicit memory for unattended material presented under high perceptual load. Our findings suggest that the null effects obtained in previous studies may not have stemmed from failures of perception or memory, but rather may have been due to insufficiently sensitive memory assessment.     

Available but unattended conceptual information in working memory: temporarily active semantic content or persistent memory for prior operations?

In 2 experiments, the authors investigated available but unattended information following working memory task demands. The experimental task presented a memory set containing exemplars from 2 conceptual categories. Following instructions to focus attention on only 1 category, priming of both categories was assessed with category comparisons of exemplar pairs. Priming was greatest for the focused category and for exemplars from the memory set (direct priming). Priming also extended to new exemplars of both categories (indirect priming) and showed little decline over more than 1 min of intervening processes. Finally, changing between category exemplars and features across memory set and comparison phases eliminated the indirect priming. These results support a persistent, operation-specific, procedural account of available but unattended conceptual information in working memory.     

Selective attention affects implicit and explicit memory for familiar pictures at different delay conditions

Three experiments investigated the effects of two variables -selective attention during encoding and delay between study and test- on implicit (picture fragment completion and object naming) and explicit (free recall and recognition) memory tests. Experiments 1 and 2 consistently indicated that (a) at all delays (immediate to 1 month), picture-fragment identification threshold was lower for the attended than the unattended pictures; (b) the attended pictures were recalled and recognized better than the unattended; and (c) attention and delay interacted in both memory tests. For implicit memory, performance decreased as delay increased for both attended and unattended pictures, but priming was more pronounced and lasted longer for the attended pictures; it was still present after a 1-month delay. For explicit memory, performance decreased as delay increased for attended pictures, but for unattended pictures performance was consistent throughout delay. By using a perceptual object naming task, Experiment 3 showed reliable implicit and explicit memory for attended but not for unattended pictures. This study indicates that picture repetition priming requires attention at the time of study and that neither delay nor attention dissociate performance in explicit and implicit memory tests; both types of memory require attention, but explicit memory does so to a larger degree.     

Semantic processing of unattended text during selective reading: how the eyes see it

Subjects were instructed to read and comprehend a target (attended) passage while eye movements were recorded. A second (unattended) passage was also present, with attended and unattended passages occupying alternating lines of text. Subsequent multiple-choice questions showed acquisition of semantic information from attended and unattended text. However, a detailed examination of eye-fixation records showed that readers occasionally fixated unattended text, indicating the presence of shifts of visual attention to unattended text. When fixations of unattended text were excluded, there was no longer any indication that readers obtained useful semantic information from unattended text.     

Visuo-spatial processing in working memory

This paper reports four experiments designed to develop a simple technique for the study of visuo-spatial processing within the working memory framework (Baddeley and Hitch, 1974). Experiment 1 involved the matching of successively presented random matrix patterns, as a secondary visual suppression task. This was coupled with rote rehearsal or a visual imagery mnemonic for learning lists of concrete words presented auditorily. Although memory performance with matching dropped overall, the visual mnemonic was differentially affected. Experiment 2 removed the matching decision, with visual presentation of unattended patterns. There was no overall effect of the unattended material, but use of the visual mnemonic was significantly affected. Experiment 3 replicated this result with simpler plain coloured squares as the unattended material.

In Experiment 4, for one group, the unattended material consisted of line drawings of common objects. For a second group, the lists of words for recall were presented visually, with or without unattended speech. The results suggested that unattended pictures disrupt use of a visual mnemonic, while unattended speech disrupts rote rehearsal.

These results suggest that unattended visual material has privileged access to the mechanism(s) involved in short-term visuo-spatial processing and storage. They also suggest that use of a concurrent visual matching task or of unattended visual material may provide tractable techniques for investigating this aspect of cognitive function within the context of working memory.     

The unattended speech effect: perception or memory?

Broadbent (1983) has suggested that the influence of unattended speech on immediate serial recall is a perceptual phenomenon rather than a memory phenomenon. In order to test this, subjects were required to classify visually presented pairs of consonants on the basis of either case or rhyme. They were tested both in silence and against a background of continuous spoken Arabic presented at 75 dB(A). No effect of unattended speech was observed on either the speed or accuracy of processing. A further study required subjects to decide whether visually presented nonwords were homophonous with real words. Again, performance was not impaired by unattended speech, although a clear effect was observed on an immediate serial memory task. Our results give no support to the perceptual interpretation of the unattended speech effect.     

Perceptual implicit memory requires attentional encoding

Perceptual implicit memory for previously attended and unattended words was measured either in a word-stem completion task or in a perceptual fluency (perceptual identification) task. Subjects (N = 144) first engaged in a focused attention task in which they were to identify one of two words presented for 100, 200, or 300 msec. Words were classified as attended if they were reported during the focused attention task and unattended if they were not. Results for both implicit memory tests indicated reliable perceptual implicit memory for attended words but not for unattended words, regardless of focused attention exposure duration. The results indicate that perceptual implicit memory tasks reflect attentional encoding processes; that is, words must undergo attentional encoding if they are to affect performance on a later perceptual implicit memory test.     

Memory for surface features of unfamiliar melodies: independent effects of changes in pitch and tempo

A melody’s identity is determined by relations between consecutive tones in terms of pitch and duration, whereas surface features (i.e., pitch level or key, tempo, and timbre) are irrelevant. Although surface features of highly familiar recordings are encoded into memory, little is known about listeners’ mental representations of melodies heard once or twice. It is also unknown whether musical pitch is represented additively or interactively with temporal information. In two experiments, listeners heard unfamiliar melodies twice in an initial exposure phase. In a subsequent test phase, they heard the same (old) melodies interspersed with new melodies. Some of the old melodies were shifted in key, tempo, or key and tempo. Listeners’ task was to rate how well they recognized each melody from the exposure phase while ignoring changes in key and tempo. Recognition ratings were higher for old melodies that stayed the same compared to those that were shifted in key or tempo, and detrimental effects of key and tempo changes were additive in between-subjects (Experiment 1) and within-subjects (Experiment 2) designs. The results confirm that surface features are remembered for melodies heard only twice. They also imply that key and tempo are processed and stored independently.     

Varieties of frequency interference in children's recognition of sentence information

The memory of fourth-grade children (9 years, 10 months of age) for information contained in target sentences presented 24 hours earlier was tested by multiple-choice recognition items each consisting of a question about a target sentence followed by three response options. The options consisted of the correct word from the sentence, a new word, and an old, incorrect word that was contained in another sentence on the study trial. The results indicated that the amount of interference produced by old information depended upon the relationship between the sentence in which the old information occurred and the target sentence—being the least when the two were unrelated; the most when the two shared the same subject noun (which also occurred in the stem of the test item for the target sentence); and intermediate when the subjects of the two sentences were synonyms. The interference produced by these manipulations was moderated by instructional strategies and the distance between the target sentence and its variation. The experiment establishes the validity of contextual frequency accrual, a construct logically necessary in extending frequency theory to recognition of information contained in sentences.     

Properties of memory for unattended spoken syllables

Whereas previous studies on memory for unattended speech have inadvertently included acoustic interference, the present study examines memory for unattended syllables during a silent period of 1, 5, or 10 s. The primary task was to read silently (Experiments 1-3) or whisper the reading (Experiment 4). Occasionally, when a light cue occurred, the subject was to recall the most recent spoken syllable, as well as the recent reading material. Memory for both the vowels and consonants of the syllables decreased across 10 s, confirming that auditory memory does decay in the absence of acoustic interference. However, the specific patterns of memory decay for vowels versus consonants depended on task demands, including the allocation of attention and the opportunity for subvocal coding. We suggest an account of performance that includes auditory sensory and phonetic memory codes with different properties, used in combination.     

Reduced attentional focus and the influence on expert anticipatory perception

The anticipatory memory encodings of expert and novice basketball players were examined under conditions of both full (attended condition) and reduced (unattended condition) attention (see also Gorman, Abernethy, & Farrow in Attention, Perception, & Psychophysics, 75, 835–844, 2013a). Participants completed a typical pattern recall task using dynamic playing sequences from basketball, and their responses were compared to both the original target pattern as well as to the series of patterns that occurred immediately after and immediately before the target image. The latter had not previously been employed in a pattern recall task when examining the anticipatory encoding of pattern information. Results revealed that the overall extent of the forward displacement for both the attended and unattended patterns was generally significantly greater for the experts, with the expert advantage tending to be most prominent for the attacking patterns. The novel addition of both forward and backward scenes may provide a more precise measure of the anticipatory effect, suggesting that future research in this domain should use a similar methodological design.     

Lingering effects of inattention on the recognition of novel forms

Two experiments are reported in which participants were instructed to attend to one of two overlapping figures and report how distinctive it was (Experiment 1), or how angular it was or what it resembled (Experiment 2). Tests of recognition memory indicated that recognition of the unattended figures was below chance, consistent with the conclusion that an implicit memory of the unattended figures and an “action tag” to not respond to the figures combine at recognition to suppress positive identification. Furthermore, participants that scored high on an index of working memory ability showed worse memory for the unattended shapes, suggesting that the ability to control attention not only enhances memory for attended items, but also leads to greater suppression of unattended distractors.     

工作记忆对类比推理的影响

该实验采用2(类比推理类型)×6(组别)双因素实验设计来探讨工作记忆与类比推理之间的关系,尤其关注工作记忆的各个子成分对类比推理的影响。控制组的被试只需完成类比推理测验,而实验组的被试是在双任务的条件下进行实验。结果表明,工作记忆是影响类比推理的一个重要因素。在图形类比推理中,主要有视空间模板中的空间成分,语音回路中的发音成分以及中央执行器的参与;在言语类比推理中,则是视空间模板中的空间成分起主要作用。     

The effects of age and divided attention on spontaneous recognition

Studies of recognition typically involve tests in which the participant’s memory for a stimulus is directly questioned. There are occasions however, in which memory occurs more spontaneously (e.g., an acquaintance seeming familiar out of context). Spontaneous recognition was investigated in a novel paradigm involving study of pictures and words followed by recognition judgments on stimuli with an old or new word superimposed over an old or new picture. Participants were instructed to make their recognition decision on either the picture or word and to ignore the distracting stimulus. Spontaneous recognition was measured as the influence of old vs. new distracters on target recognition. Across two experiments, older adults and younger adults placed under divided-attention showed a greater tendency to spontaneously recognize old distracters as compared to full-attention younger adults. The occurrence of spontaneous recognition is discussed in relation to ability to constrain retrieval to goal-relevant information.     

The repressor personality and avoidant information processing: A dichotic listening study

The present research was designed to investigate the proposition that repressors, operationally defined by the conjunction of low anxiety and high defensiveness, are particularly adept at avoiding the processing of information when motivated to do so. Four groups of participants (nondefensive-low anxious, high anxious, repressors, and defensive-high anxious) were administered a dichotic listening task involving neutral or negative affective words presented in the unattended ear. Participants shadowed the material presented to the attended ear and simultaneously responded to a probe task presented on a video monitor. Results revealed that repressors made significantly fewer shadowing errors than high anxious and defensive-high anxious participants and marginally significantly fewer shadowing errors than low anxious participants for both neutral and negative words. High anxious participants, however, were later able to recognize the negative words that had been presented to the unattended ear at well above chance levels, whereas the recognition memory of repressors for such negative unattended words was at chance levels. In addition, repressors' responses to a postexperiment questionnaire indicated a significantly greater number of distracting thoughts during the experiment relative to other participants. Repressors, it seems, are indeed skillful at avoidant information processing and this capacity may well be related to the emotional memory deficits they have displayed in previous research.     

How Effective is the Enhanced Cognitive Interview when Aiding Recall Retrieval of Older Adults including Memory for Conversation?

The percentage of older adults in the general population is growing. As a result, older adults are coming more frequently into contact with the Criminal Justice System as witnesses to and victims of crime. Older adults are also over‐represented in crimes where conversation detail is of particular importance to an investigation (e.g. distraction burglary). The present study therefore examined the efficacy of cognitive interview (CI) compared with structured interview in improving the recall of an event by older witnesses, specifically conversational detail. Young adults (19–54 years old), young‐old adults (60–74 years old), and old‐old adults (75+ years old) were asked to watch a short film of a laptop theft and were then, after a 1.5 hour delay, randomly allocated to one of two interview conditions. It was found that the CI significantly increased recall of all age groups, without increasing the amount of incorrect or confabulated information reported. The individuals in the young adult and the young‐old adult conditions were found to remember significantly more than the individuals from the old‐old adult condition, without decreasing the accuracy of the information. The CI enhanced memory for conversation gist, person and action detail. Results will be discussed in relation to interviewing and investigating practices. Copyright © 2011 John Wiley & Sons, Ltd.     

Cognitive organization of impressions: effects of incongruency in complex representations

Two experiments investigated the organization in memory of expectancy-congruent and expectancy-incongruent information pertaining to multiple trait concepts in an impression-formation task. In Experiment 1, when multiple trait concepts were represented in the information describing the target person, both congruent and incongruent items reflecting the same trait concept were stored together and were directly associated in memory, and both types of items were recalled equally well. In Experiment 2, when only one trait concept was represented in the information, incongruent items were recalled with higher probability than congruent items, and the latter were not directly associated in memory. Results suggest that with increasing categorical complexity of stimulus information, processes are invoked that do not occur in simpler impression-formation contexts. Implications for theoretical models of person memory are discussed.     

Aging and interference in verbal working memory.

According to inhibitory views of working memory, old adults should have particular problems deleting irrelevant information from working memory, leading to greater interference effects compared with young adults. The authors investigated this hypothesis by using variations of an A-B, C-D retroactive interference paradigm in working memory with young and old adults. They used a recognition measure of memory, assessing both accuracy and reaction time. The primary finding was that senior adults consistently exhibited proportionally greater retroactive interference effects compared with young adults when interfering word pairs that had been read aloud had to be rejected. Patterns of recognition and reaction time data suggested that old adults' activation of target material is similar to young adults, but they experience sustained activation of irrelevant material that has entered working memory. Theoretical implications of these findings for inhibitory deficit (R. T. Zacks & L. Hasher, 1998) and source memory deficit accounts of cognitive aging are discussed.     

Event frequency and children's suggestibility: a study of cued recall responses

Research examining the effect of repeated experience on children's suggestibility for particular kinds of information has produced differing results. In one study, responses to recognition questions revealed heightened suggestibility for variable details in children who repeatedly experienced an event compared to children who experienced an event once. In other studies, no such effect was found with cued recall. In this study, 4–5‐year old children engaged in one or four play sessions. Children were later given a biasing interview wherein half of the details were incorrectly represented. Children were then given a final memory test using free and cued recall prompts that was preceded by one of three instruction types: no special instructions, moderate instructions, or opposition instructions. Children in the repeated‐event condition were more suggestible than those in the single‐event condition, regardless of instructions. No significant differences in suggestibility were found across instructions conditions. Copyright © 2004 John Wiley & Sons, Ltd.