Subsequent Recognition Performance Research Articles

Neural Suppression of Irrelevant Information Underlies Optimal Working Memory Performance

Our ability to focus attention on task-relevant information and ignore distractions is reflected by differential enhancement and suppression of neural activity in sensory cortex (i.e., top-down modulation). Such selective, goal-directed modulation of activity may be intimately related to memory, such that the focus of attention biases the likelihood of successfully maintaining relevant information by limiting interference from irrelevant stimuli. Despite recent studies elucidating the mechanistic overlap between attention and memory, the relationship between top-down modulation of visual processing during working memory (WM) encoding, and subsequent recognition performance has not yet been established. Here, we provide neurophysiological evidence in healthy, young adults that top-down modulation of early visual processing (< 200 ms from stimulus onset) is intimately related to subsequent WM performance, such that the likelihood of successfully remembering relevant information is associated with limiting interference from irrelevant stimuli. The consequences of a failure to ignore distractors on recognition performance was replicated for two types of feature-based memory, motion direction and color. Moreover, attention to irrelevant stimuli was reflected neurally during the WM maintenance period as an increased memory load. These results suggest that neural enhancement of relevant information is not the primary determinant of high-level performance, but rather optimal WM performance is dependent on effectively filtering irrelevant information through neural suppression to prevent overloading a limited memory capacity.

An event-related potential investigation of the processing of Remember/Forget cues and item encoding in item-method directed forgetting

This study examined the electrophysiological correlates of the processing of the Remember/Forget cues and the successful encoding of study items in item-method directed forgetting. Subjects engaged in an old/new recognition test and an item-method directed forgetting task. Event-related potentials (ERPs) time-locked to study items and Remember/Forget cues were compared according to the subsequent recognition performance. A reliable subsequent memory effect was elicited by the study items in the old/new recognition test. In contrast, the study items in the directed forgetting task did not yield reliable subsequent memory effects. Importantly, the Remember/Forget cues gave rise to ERPs that were predictive of the subsequent recognition performance to the study items preceding the cues. The subsequent memory effect elicited by the Remember cues was more sustained than that elicited by the Forget cues and showed distinct scalp distribution during the extended period. These results suggest that study items in the directed forgetting task are maintained in short-term memory with minimal further processing until the presentation of the Remember/Forget cues. In addition, the encoding mechanisms engaged by Remember cues and Forget cues are not entirely equivalent.

Does the presence of priming hinder subsequent recognition or recall performance?

Declarative and non-declarative memories are thought be supported by two distinct memory systems that are often posited not to interact. However, Wagner, Maril, and Schacter (2000a) reported that at the time priming was assessed, greater behavioural and neural priming was associated with lower levels of subsequent recognition memory, demonstrating an interaction between declarative and non-declarative memory. We examined this finding using a similar paradigm, in which participants made the same or different semantic word judgements following a short or long lag and subsequent memory test. We found a similar overall pattern of results, with greater behavioural priming associated with a decrease in recognition and recall performance. However, neither various within-participant nor various between-participant analyses revealed significant correlations between priming and subsequent memory performance. These data suggest that both lag and task have effects on priming and declarative memory performance, but that they are largely independent and occur in parallel.

Age-related ERP differences at retrieval persist despite age-invariant performance and left-frontal negativity during encoding

Although it has been reported repeatedly that retrieval-related processes decline with aging, the influence of well-documented age-related encoding deficiencies on the observed changes at retrieval have not been ruled out as a contributing factor. Here, we disentangle this confound by using a serendipitous finding reported by Nessler et al. [D. Nessler, R. Johnson Jr., M. Bersick, D. Friedman, On why the elderly have normal semantic retrieval but deficient episodic encoding: a study of left inferior frontal ERP activity, Neuroimage 30 (2006) 299-312]. In that study, age-related differences in the magnitude of left inferior frontal brain activity at encoding and subsequent recognition memory performance were eliminated when a deeper level of semantic encoding in the older adults was compared with a shallow level in the young. Based on this earlier result, the present paper is concerned with the question of whether the matched recognition performance resulting from age-equivalent ERP encoding activity was also accompanied by age-invariant retrieval-related brain activity. The results in the young were consistent with dual-process models of recognition memory due to the presence of ERP activity linked previously to familiarity (frontal EM effect) and recollection (parietal EM effect). By contrast the older adults only showed evidence of familiarity-based processes. Thus, despite age-equivalent brain activity at encoding and subsequent recognition performance, older relative to young adults appeared to base their old-new decisions on a qualitatively different pattern of retrieval processes (i.e., more on familiarity and less on recollection). Consequently, these data suggest that the age-related changes in retrieval observed here are independent of, and likely occur in addition to, any age-related changes in encoding processes.

Influence of attentional demands on the processing of emotional facial expressions in the amygdala

Recent studies have cast doubts on the appealing idea that the processing of threat-related stimuli in the amygdala is unconstrained by the availability of attentional resources. However, these studies exclusively used face stimuli presented at fixation and it is unclear whether their conclusion can apply to peripheral face stimuli. Thus, we designed an experiment in which we manipulated the perceptual attentional load of the task used to divert attention from peripheral face stimuli: participants were presented simultaneously with four peripheral pictures (two faces, either both neutral or both fearful, and two houses) that were slightly tilted, and had to match two of these pictures (defined by their position on the screen) either for orientation of the tilt or for identity. The identity task was confirmed to involve greater attentional load than the orientation task by differences in accuracy, reaction times, subsequent face recognition performance, and patterns of activation in several cortical regions. In the orientation task, ignored fearful faces led to stronger activation in the right amygdala than ignored neutral faces. However, this differential response was abolished when participants performed the difficult identity-matching task. Thus, emotional processing of peripheral faces in the amygdala also appears to depend on the available perceptual attentional resources.

Perirhinal cortex damage and anterograde object-recognition in rats after long retention intervals

Damage to the perirhinal cortex (PRh) in rats impairs anterograde object-recognition memory after retention intervals of up to several hours, but there is little direct evidence to link PRh function to object-recognition abilities after substantially longer intervals that span several days or weeks. We assessed the effects of PRh lesions on anterograde object recognition using a novel-object preference test, with retention intervals lasting 24 h and 3 weeks. The rats received multiple exposures to the sample object during the learning phase—5 min per day on 5 consecutive days. Control rats displayed a significant novel-object preference after both retention intervals, indicating recognition of the sample object, whereas the rats with PRh lesions displayed a significant preference after the 24-h interval, but not after the 3-week interval. When the learning phase of the trial was shortened to a single 5-min session, the PRh group was impaired in the 24-h condition. The findings indicate that the disruptive effects of PRh damage on anterograde object recognition persist over very long postlearning intervals. The results indicate further that object recognition impairments following PRh damage are not ubiquitous, and that learning conditions play a significant role in determining the subsequent recognition performance in rats with PRh damage.

Eye-Witnesses Should Not Do Cryptic Crosswords Prior to Identity Parades

Navon letter tasks have been shown to affect subsequent face recognition performance. As such tasks are not likely to by carried out prior to a witness attending an identity parade this is unlikely to have much applied relevance. Here, however, it is explored how a range of puzzles that witnesses might engage in affect face recognition. Cryptic crosswords were found to have a detrimental effect on subsequent face recognition, unlike reading, literal crosswords, or sudoku. As well as this finding's practical importance, it also provides a further insight into the Navon effect on face processing.

Metamemory in Schizophrenia: An Exploration of the Feeling-of-Knowing State

The ability to monitor memory performance has considerable importance in everyday life and is among the proposed metamemory dimensions which has been widely investigated. The ability to monitor memory performance accurately was examined in 16 patients with schizophrenia and 16 control subjects by using a Feeling-of-Knowing task on episodic information. Feeling-of-Knowing judgments are predictions made about the likelihood of subsequent recognition of currently non-recallable information. Participants were given cued recall and recognition tests of 50 sentence-target words. Feeling-of-knowing judgments were made for non-recalled targets. Our results first confirm that schizophrenia is associated with episodic memory impairment. By using the Feeling-of-Knowing task, patients with schizophrenia were found to predict accurately their subsequent recognition performance, suggesting an interesting dissociation between a preserved metamemory and an altered memory. This work was supported by INSERM (Institut National de la Santé et de la Recherche Médicale).

Olfaction and Depth of Word Processing: A Magnetoencephalographic Study

Using a whole-cortex magnetoencephalograph, magnetic field changes were recorded to describe brain activities related to simultaneous visual and olfactory processing and to detect odor-related influences on verbal information processing. Words had to be either shallowly (nonsemantic) or deeply (semantic) encoded by healthy young subjects, each of these tasks under two different kinds of olfactory stimulation. After each encoding phase, word recognition performance was tested. First, the odor was randomly associated with some of the study words (simultaneous stimulation; same duration as for words) for both depths of word processing conditions, and second, continuous olfactory stimulation (permanent stimulation) was provided during the whole study phases of both depths of word processing conditions. The statistical analysis of the physiological data revealed evidence of a specific odor-induced effect depending on depth of word processing and kind of olfactory stimulation. Brain activity between about 250 and 450 ms as well as between about 650 and 1000 ms after stimulus onset was found to vary as a function of odor delivery and depth of word processing. In addition, a significant effect of odor stimulation on subsequent word recognition performance occurred in case of simultaneous odor stimulation and semantic word encoding. It is interpreted that in this case, word recognition performance significantly decreased because of the presence of the odor during prior word encoding. Such a behavioral effect was missing in all other conditions. The present psychological and physiological findings support the idea that semantic word encoding is specifically affected by simultaneous olfactory information processing. It is concluded that this phenomenon is due to a competition with cortical regions related to language and olfactory information processing, as suggested by T. S. Lorig (1999, Neurosci. Biobehav. Rev. 23, 391–398).

Feeling-of-knowing judgments do not predict subsequent recognition performance for eyewitness memory.

On the basis of recent theories of metacognition, the authors predicted that eyewitnesses would be accurate in then confidence judgments for recall but not in their feeling-of-knowing (FOK) judgments. In 3 studies, participants were presented with crime scenarios on video and acted as witnesses. Participants attempted to answer cued-recall questions and either rated their recall confidence or predicted their subsequent ability to recognize unrecalled answers. FOK accuracy was determined using a final recognition test. Although confidence judgments were predictive, in all 3 experiments, FOK accuracy was at chance. The authors argued that the low FOK accuracy reflects the lack of effectiveness of the metacognitive heuristics used in eyewitness memory. Consequently, the authors predicted that in an applied setting, prediction of future recognition performance for unrecalled eyewitness material is likely to be at chance.

Feeling-of-knowing judgments do not predict subsequent recognition performance for eyewitness memory.

Feeling-of-knowing judgments do not predict subsequent recognition performance for eyewitness memory.

Whom do words hurt? Individual differences in susceptibility to verbal overshadowing

The phenomenon of verbal overshadowing, in which describing memory for nonverbal stimuli (e.g. faces, tastes, or music) interferes with subsequent recognition performance, has previously been associated with situations in which participants' perceptual expertise exceeded their verbal expertise (e.g. Melcher and Schooler, 1996). Such findings suggest that individual differences in perceptual and verbal ability should predict who will be vulnerable to verbalization. In this study participants performed six trials of a standard verbal overshadowing procedure (viewing a face, verbally recalling it or engaging in an unrelated activity, followed by taking a forced choice recognition test). Perceptual ability was assessed using both a domain specific measure (face recognition ability) and non-specific measures (e.g. embedded figures). General verbal ability was determined on the basis of high school or college GPA. As predicted, verbal overshadowing (i.e. lower performance for verbalization relative to control participants) was greatest among participants with high perceptual expertise and low verbal expertise. This relationship was observed with both the domain-specific and domain-general measures of perceptual expertise. These findings suggest that individuals may be especially vulnerable to verbal overshadowing when their general perceptual abilities exceed their verbal abilities. Copyright © 1998 John Wiley & Sons, Ltd.

Whom do words hurt? Individual differences in susceptibility to verbal overshadowing

SUMMARY The phenomenon of verbal overshadowing, in which describing memory for nonverbal stimuli (e.g. faces, tastes, or music) interferes with subsequent recognition performance, has previously been associated with situations in which participants’ perceptual expertise exceeded their verbal expertise (e.g. Melcher and Schooler, 1996). Such findings suggest that individual diAerences in perceptual and verbal ability should predict who will be vulnerable to verbalization. In this study participants performed six trials of a standard verbal overshadowing procedure (viewing a face, verbally recalling it or engaging in an unrelated activity, followed by taking a forced choice recognition test). Perceptual ability was assessed using both a domain specific measure (face recognition ability) and non-specific measures (e.g. embedded figures). General verbal ability was determined on the basis of high school or college GPA. As predicted, verbal overshadowing (i.e. lower performance for verbalization relative to control participants) was greatest among participants with high perceptual expertise and low verbal expertise. This relationship was observed with both the domain-specific and domain-general measures of perceptual expertise. These findings suggest that individuals may be especially vulnerable to verbal overshadowing when their general perceptual abilities exceed their verbal abilities. #1998 John Wiley & Sons, Ltd. Appl. Cognit. Psychol. 12: S105‐S125 (1998)

Grieving fathers: Helping pediatric oncology nurses help them

It is widely believed that verbal processing generally improves memory performance. However, in a series of six experiments, verbalizing the appearance of previously seen visual stimuli impaired subsequent recognition performance. In Experiment 1, subjects viewed a videotape including a salient individual. Later, some subjects described the individual's face. Subjects who verbalized the face performed less well on a subsequent recognition test than control subjects who did not engage in memory verbalization. The results of Experiment 2 replicated those of Experiment 1 and further clarified the effect of memory verbalization by demonstrating that visualization does not impair face recognition. In Experiments 3 and 4 we explored the hypothesis that memory verbalization impairs memory for stimuli that are difficult to put into words. In Experiment 3 memory impairment followed the verbalization of a different visual stimulus: color. In Experiment 4 marginal memory improvement followed the verbalization of a verbal stimulus: a brief spoken statement. In Experiments 5 and 6 the source of verbally induced memory impairment was explored. The results of Experiment 5 suggested that the impairment does not reflect a temporary verbal set, but rather indicates relatively long-lasting memory interference. Finally, Experiment 6 demonstrated that limiting subjects' time to make recognition decisions alleviates the impairment, suggesting that memory verbalization overshadows but does not eradicate the original visual memory. This collection of results is consistent with a recoding interference hypothesis: verbalizing a visual memory may produce a verbally biased memory representation that can interfere with the application of the original visual memory.

Describing Faces from Memory: Accuracy and Effects on Subsequent Recognition Performance

The present research examines: (a) the accuracy of three face description methods, and (b) the effects of post-exposure description and imaging activities on subsequent face recognition performance. Participants viewed a sequence of six target photographs, and after each, performed one of three description tasks: generated their own set of descriptors, checked-off descriptors from a pre-existing list, or rated the same set of descriptors on bipolar scales. Other participants performed a distractor (control) activity. Additionally, participants were either told or not told to image the targets while they simultaneously performed the description tasks. Results showed that the checklist task lowered subsequent recognition performance compared to the generate task. Imaging with the generate task facilitated recognition, but imaging with the checklist and rating tasks degraded recognition. The generate task produced the highest quality descriptions as determined by other participants' performance in matching the descriptions to face photographs. The checklist decrement is discussed in terms of memorial confusion initiated by the presence of irrelevant face cues. These results indicate that descriptor generation is the preferred method of collecting eyewitness' face descriptions.

Massed versus distributed exposure and imaging of faces: Changing the test view

This research examined the effects of massed versus distributed exposure and imaging of faces, and the effects of changing the study-to-test view on subsequent recognition performance. The massed procedure consisted of individual faces exposed once for 6 s, followed by a 30 s off period. The distributed procedure consisted of faces exposed three times for 2 s, followed by a 10 s off period after each exposure. During the off periods, groups of participants either imaged the previous face, imaged another face, or performed an irrelevant letter-search task. Results showed that distributed exposure and post-exposure imaging of target faces facilitated recognition, but these effects primarily occurred when the same facial view was given at both study and test. Recognition diminished when the target was presented in a different view at test, but when combined with distributed presentation and target imaging, performance was enhanced. Implications for suspect identification and recognition of other kinds of complex visual stimuli are discussed.

Effects of Post-exposure Description and Imaging on Subsequent Face Recognition Performance

After viewing a crime, witnesses are frequently asked by police investigators to give a verbal description of the perpetrator. At a later time, witnesses may be asked to try to recognize the perpetrator in a lineup or a mugfile. The purpose of this research was to determine whether performance on a later recognition test is influenced by an earlier verbal description test of the target. Participants viewed six target faces, and after each, performed one of four post-exposure activities. Two were verbal description tasks. The descriptor checklist task had participants indicate, using a list of potential adjectives, those descriptors that best described the most recently seen face. The descriptor generate task had participants recall descriptors that best described the most recently seen face. Both description tasks were accomplished using a questionnaire that was identical except for the presence or absence of specific adjectives. Other participants were instructed to image the target face or they performed an irrelevant task during the post-exposure period. In a later recognition test, participants tried to find the targets in a set of faces containing 134 distractors. The results showed that participants using the checklist produced lower performance on the recognition test than participants who generated their own descriptors. Imaging produced the highest recognition performance but was not significantly different from the irrelevant condition. The recognition decrement of the descriptor checklist is explained in terms of interference caused by the presence of irrelevant face descriptors that added noise to participants' memory of the targets. Implications for testing witness memory by police investigators are discussed. For example, if verbal descriptions of faces are requested from eyewitnesses, descriptor recall may be preferred over a descriptor recognition because the former task does not degrade later recognition of the perpetrator.

Verbal overshadowing of visual memories: Some things are better left unsaid

It is widely believed that verbal processing generally improves memory performance. However, in a series of six experiments, verbalizing the appearance of previously seen visual stimuli impaired subsequent recognition performance. In Experiment 1, subjects viewed a videotape including a salient individual. Later, some subjects described the individual's face. Subjects who verbalized the face performed less well on a subsequent recognition test than control subjects who did not engage in memory verbalization. The results of Experiment 2 replicated those of Experiment 1 and further clarified the effect of memory verbalization by demonstrating that visualization does not impair face recognition. In Experiments 3 and 4 we explored the hypothesis that memory verbalization impairs memory for stimuli that are difficult to put into words. In Experiment 3 memory impairment followed the verbalization of a different visual stimulus: color. In Experiment 4 marginal memory improvement followed the verbalization of a verbal stimulus: a brief spoken statement. In Experiments 5 and 6 the source of verbally induced memory impairment was explored. The results of Experiment 5 suggested that the impairment does not reflect a temporary verbal set, but rather indicates relatively long-lasting memory interference. Finally, Experiment 6 demonstrated that limiting subjects' time to make recognition decisions alleviates the impairment, suggesting that memory verbalization overshadows but does not eradicate the original visual memory. This collection of results is consistent with a recoding interference hypothesis: verbalizing a visual memory may produce a verbally biased memory representation that can interfere with the application of the original visual memory.

The effects of time of day and subjects' test expectations on recall and recognition of prose materials

This paper reports an experiment which investigated the effects of time of day and type of test expected (recall or recognition) on subjects' subsequent recall and recognition performance. The results of the recall test showed that better performance was associated with recall instructions in the afternoon (5 p.m.), but with recognition instructions in the morning (9 a.m.). The data from the recognition test showed that the morning subjects performed particularly well when they were expecting a recognition test, but that the afternoon subjects' performance was not affected by instructions. The results are discussed in relation to subjects' preferred processing strategies at different times of day.

ERPs predictive of subsequent recall and recognition performance

By exploiting measures of information processing complementary to those obtained from behavioral studies, electrophysiological studies of human memory may provide insights into the cognitive processes associated with encoding. In the present experiment, subjects viewed words under incidental learning conditions in which each word required a two-choice decision based on semantic criteria ( interesting/uninteresting or edible/inedible). Memory for those words was subsequently assessed by a free recall test and then a recognition test. Event-related brain potentials elicited in response to the original presentation of each word were found to differ as a function of later memory performance. Over the 400–800 ms latency range, responses to remembered words were positive relative to responses to forgotten words, especially for recall. These electrophysiological differences are interpreted as reflections of processes that correlated with encoding.