A dissociation between similarity effects in episodic face recognition

University of Newcastle, Callaghan, New South Wales, Australia Memory similarity, the similarity between a test lure and memory traces, reduces confidence and accuracy in all forms of recognition memory. In contrast, Tulving (1981) showed that, in recognition memory for scenic pictures, choice similarity, the similarity between forced choice test alternatives, increased accuracy but decreased confidence. In the present study, we replicated both memory and choice similarity effects and the dissociation between accuracy and confidence with pictures of faces. State-trace analysis confirmed the dissociation and identified two dimensions underlying these effects, one associated with choice similarity and another associated with memory similarity. Further analysis showed that the effect of study—test lag was associated with the memory-similarity dimension.     

Recognition,recollection, familiarity and executive function in medicated patients with moderate Parkinson's disease

There is conflicting evidence about whether Parkinson's disease (PD) is associated with deficiencies in recognition memory (RM) and the processes which underlie it, namely recollection (a form of recall) and familiarity (a feeling of memory in the absence of recall). The aims of the current study were to examine forced‐choice verbal RM (assessed with the Warrington Recognition memory Test), yes‐no RM, recollection, familiarity and executive functioning in 17 patients with moderate PD and 17 healthy volunteers matched for age and premorbid intelligence. We predicted that patients with moderate PD would display a significant recollection deficit on the yes‐no RM test, because their strategic memory processing that depends on executive functioning and is necessary for efficient encoding and/or retrieval, was disrupted. In contrast, familiarity memory, which is not dependent on these processes, and forced‐choice RM (which is largely dependent on familiarity) should show higher levels of preservation. We also predicted that recollection should be correlated with severity of executive dysfunction. Our findings revealed that the PD patients were as likely to accurately discriminate between targets and distractors as the healthy volunteers on both RM tests. However, the PD patients were significantly less reliant on recollection‐driven recognition decisions on the yes‐no RM test when compared with the healthy control group. The patients also displayed executive function deficits, but these were not correlated with recollection. The extent to which the PD patients' reliance on familiarity at the expense of recollection is explained by impairments in strategic memory processes/executive function and/or medial temporal lobe retrieval processes needs further exploration.     

Do object refixations during scene viewing indicate rehearsal in visual working memory?

Do refixations serve a rehearsal function in visual working memory (VWM)? We analyzed refixations from observers freely viewing multiobject scenes. An eyetracker was used to limit the viewing of a scene to a specified number of objects fixated after the target (intervening objects), followed by a four-alternative forced choice recognition test. Results showed that the probability of target refixation increased with the number of fixated intervening objects, and these refixations produced a 16% accuracy benefit over the first five intervening-object conditions. Additionally, refixations most frequently occurred after fixations on only one to two other objects, regardless of the intervening-object condition. These behaviors could not be explained by random or minimally constrained computational models; a VWM component was required to completely describe these data. We explain these findings in terms of a monitor–refixate rehearsal system: The activations of object representations in VWM are monitored, with refixations occurring when these activations decrease suddenly.     

On the use of discrimination to assess memory

A number of studies have made use of sensory discrimination to assess memory. These experiments have typically employed a temporal two-alternative forced choice paradigm in which the interstimulus interval (ISI) is varied. Many of these tests have shown that ISI has little or no effect on discrimination performance. This has been taken as evidence for perfect or very good memory. An alternative interpretation would be that discrimination tests lack sufficient sensitivity to reveal memory effects. In the present study, computer simulations based on signal detection theory were used to estimate the relative effects of memory noise and direct noise (i.e., noise inherent in the discrimination task) on discrimination performance. These simulations indicate that the amount of memory noise has to be quite large to cause a marked elevation in discrimination thresholds and that sensory discrimination is a relatively insensitive test of memory.     

Learning strategies as determinants of memory deficiencies

Two tests were made of inferences about how learning strategies affect recall accuracy, and how peculiarities of strategy might account for mentally retardeds' memory deficiencies. Learning strategy was defined as the pattern of pauses generated by S as he paced himself through serial lists of letters. When given freedom to proceed as they wished, normally intelligent Ss paused increasingly the deeper they went into the list. Retarded Ss did not. It was concluded that the normals' active strategies contribute to their high primacy, while the retardeds' lack of distinctive pauses accounts for their low primacy. In the second test, the strategies were reversed. The normals were forced to abandon rehearsal; the retardeds were forced to rehearse. This resulted in greatly enhanced primacy for the retardeds, and greatly decreased primacy for the normals. In addition to showing how spontaneous strategies and forced strategies can directly influence recall accuracy, these findings suggest a reasonably simple means of mitigating short-term memory deficiencies.     

Metamemory in tufted capuchin monkeys (Cebus apella)

Whereas evidence for metacognition by nonhuman primates has been obtained in great apes and old world monkeys, it is weaker in new world monkeys. For instance, capuchin monkeys may fail to recognize their own knowledge of the location of invisible bait. In the present study, we tested whether tufted capuchin monkeys would flexibly change their behavior in a delayed matching-to-sample (DMTS) test depending upon the strength of their memory trace of the sample. In Experiment 1, two monkeys were tested on a modified 9-alternative DMTS task with various delays on a computerized display. In some trials, the monkeys could choose whether to go for a memory test or for a simple key touch as an escape from the test. In other trials, they were forced to go for the memory test. Both monkeys escaped from the memory test more often when their matching accuracy on forced tests was lower. In one of the monkeys, the matching accuracies on chosen memory tests decreased more slowly as a function of delay length, and were higher after long delays than those on forced memory tests. This suggests that at least one capuchin monkey was able to recognize the strength of his own memory trace. Experiment 2 employed occasional no-sample tests, in which the monkeys faced the task choice without presentation of any sample for the trial. The monkey who was successful in Experiment 1 declined the memory test more often in no-sample trials than regular trials, further indicating metamemory in this individual. In Experiment 3, this successful monkey received a task, in which he was sometimes able to choose between shape MTS or texture MTS tasks. However, his matching accuracies did not differ between chosen tasks and forced tasks. Thus, the metamemory possessed by this new world monkey species may be more like a flag, showing strength of memory trace, than an elaborate representation showing details of the memory trace.     

Aging and recognition memory for emotional words: A bias account

The present study investigated age-related differences in the locus of the emotional enhancement effect in recognition memory. Younger and older adults studied an emotion-heterogeneous list followed by a forced choice recognition memory test. Luce’s (1963) similarity choice model was used to assess whether emotional valence impacts memory sensitivity or response bias. Results revealed that the emotional enhancement effect in both age groups was due to a more liberal response bias for emotional words. However, the pattern of bias differed, with younger adults more willing to classify negative words as old and older adults more willing to classify positive words as old. The results challenge the conclusion that emotional words are more memorable than neutral words.     

Anticipatory scene representation in preschool children's recall and recognition memory

Behavioral and neuroscience research on boundary extension (false memory beyond the edges of a view of a scene) has provided new insights into the constructive nature of scene representation, and motivates questions about development. Early research with children (as young as 6–7 years) was consistent with boundary extension, but relied on an analysis of spatial errors in drawings which are open to alternative explanations (e.g. drawing ability). Experiment 1 replicated and extended prior drawing results with 4–5‐year‐olds and adults. In Experiment 2, a new, forced‐choice immediate recognition memory test was implemented with the same children. On each trial, a card (photograph of a simple scene) was immediately replaced by a test card (identical view and either a closer or more wide‐angle view) and participants indicated which one matched the original view. Error patterns supported boundary extension; identical photographs were more frequently rejected when the closer view was the original view, than vice versa. This asymmetry was not attributable to a selection bias (guessing tasks; Experiments 3–5). In Experiment 4, working memory load was increased by presenting more expansive views of more complex scenes. Again, children exhibited boundary extension, but now adults did not, unless stimulus duration was reduced to 5 s (limiting time to implement strategies; Experiment 5). We propose that like adults, children interpret photographs as views of places in the world; they extrapolate the anticipated continuation of the scene beyond the view and misattribute it to having been seen. Developmental differences in source attribution decision processes provide an explanation for the age‐related differences observed.     

The influence of episodic memory decline on value-based choice

Recent studies suggest the involvement of episodic memory in value-based decisions as a source of information about subjective values of choice options. We therefore tested the link between age-related memory decline and inconsistencies in value-based decisions in 30 cognitively healthy older adults. Within the pre-registered experiment, the inconsistencies were measured in two ways: i) the consistency between stated preferences and revealed choices; ii) the amount of intransitivities in choice triplets, revealed in a forced paired choice task including all possible pairings of 20 food products. Although no significant association of memory functions to number of intransitive triplets was observed, participants with lower memory scores were more likely to choose the item for which they stated a lower preference. The results suggest a higher noise in the underlying preference signal in participants with lower memory. We discuss the results in the context of the unique needs of elderly consumers.     

Serial position curves in short-term memory: functional equivalence across modalities

Four experiments investigated item and order memory for sequences of seen unfamiliar faces and heard nonwords. Experiments 1 and 3 found bowed serial position curves using the serial reconstruction test of order with faces and nonwords, respectively. Experiments 2 and 4 found limited recency, no primacy, and above chance performance on all items using a two-alternative forced choice (2AFC) test of item recognition, again with faces and nonwords. These results suggest that the different serial position curves typically found using traditional paradigms for exploring visual and verbal short-term memory are due to differences in the methods used rather than modality-specific mechanisms.     

What’s “inattentional” about inattentional blindness?

In a recent commentary, Memmert critiqued claims that attentional misdirection is directly analogous to inattentional blindness (IB) and cautioned against assuming too close a similarity between the two phenomena. One important difference highlighted in his analysis is that most lab-based inductions of IB rely on the taxing of attention through a demanding primary task, whereas attentional misdirection typically involves simply the orchestration of spatial attention. The present commentary argues that, rather than reflecting a complete dissociation between IB and attentional misdirection, this difference highlights potential grounds for delineating mechanistically distinct forms of IB: spatial inattentional blindness, which stems from the covert misallocation of spatial attention, and central inattentional blindness, which stems from disruption or preoccupation of perceptual mechanisms that interface with higher-level processes such as working memory. Recognition of such distinctions can help situate theoretical understanding of IB more firmly within the context of the broader attention literature.     

Overcoming unlearned response biases: delayed escape following errors facilitates acquisition of win-stay and win-shift working memory water-escape tasks in rats

Previous research has demonstrated that perseveration in escape situations is an unlearned response bias of rats and mice which is difficult to overcome. In Experiment I, Sprague-Dawley rats were trained to a criterion of nine correct choices in 10 consecutive trials in a win-stay working memory water-escape task wherein an escape platform was hidden in one of two compartments. Subjects were given a forced choice on an Information Trial followed by a free choice on a Test Trial 5 min later. Subjects who were given a 30-s forced swim in the incorrect section following errors on the Test Trial showed faster acquisition and less use of response perseveration than control subjects. In Experiment II, the delayed escape procedure was used to compare acquisition of win-stay and win-shift strategies. Contrary to previous research both groups learned the tasks, although the win-stay group showed better performance. It is concluded that unlearned response biases of perseverating and returning to previous escape sites can be overcome if experimental conditions are appropriately arranged.     

The role of unconscious memory errors in judgments of confidence for sentence recognition

The present experiment tested the hypothesis that unconscious reconstructive memory processing can lead to the breakdown of the relationship between memory confidence and memory accuracy. Participants heard deceptive schema-inference sentences and nondeceptive sentences and were tested with either simple or forced-choice recognition. The nondeceptive items showed a positive relation between confidence and accuracy in both simple and forced-choice recognition. However, the deceptive items showed a strong negative confidence/accuracy relationship in simple recognition and a low positive relationship in forced choice. The mean levels of confidence for erroneous responses for deceptive items were inappropriately high in simple recognition but lower in forced choice. These results suggest that unconscious reconstructive memory processes involved in memory for the deceptive schema-inference items led to inaccurate confidence judgments and that, when participants were made aware of the deceptive nature of the schema-inference items through the use of a forced-choice procedure, they adjusted their confidence accordingly.     

Forced confabulation affects memory sensitivity as well as response bias

A signal detection analysis assessed the extent to which forced confabulation results from a change in memory sensitivity (d _a ), as well as response criterion (β). After viewing a crime video, participants answered 14 answerable and 6 unanswerable questions. Those in the voluntary guess condition had a “don’t know” response option; those in the forced guess condition did not. One week later, the same questions were answered using a recognition memory test that included each participant’s initial responses. As was predicted, on both answerable and unanswerable questions, participants in the forced guess condition had significantly lower response criteria than did those who voluntarily guessed. Furthermore, on both answerable and unanswerable questions, d _a scores were also significantly lower in the forced than in the voluntary guess condition. Thus, the forced confabulation effect is a real memory effect above and beyond the effects of response bias; forcing eyewitnesses to guess or speculate can actually change their memory.     

Relationship of cognitive strategy use to prospective memory performance in a diverse sample of nondemented older adults with varying degrees of cognitive complaints and impairment

Although older adults typically have better performance on prospective memory (PM) tasks carried out in naturalistic settings, a paucity of research directly assesses older adults’ use of compensatory strategies on such tasks. The current study investigates external memory strategy use during performance of a clinical PM test that features both short-term (in laboratory) and long-term (out of laboratory) subtasks (i.e., the Royal Prince Alfred Prospective Memory Test – RPA-ProMem. Nondemented, community-dwelling older adults (n = 214; mean age = 80.5; 68.2% female; 39.7% non-white) with mild cognitive impairment, subjective cognitive decline, and healthy controls completed the RPA-ProMem while external strategy use was permitted and recorded. Overall, participants utilized external strategies 41% of the time on the RPA-ProMem. Increased utilization of external memory strategies was significantly associated with better PM performance. Additionally, better performance on executive functioning tasks was associated with increased use of external memory strategies. Results are discussed in relation to how memory strategy use can be enhanced to improve everyday memory ability in older adults at risk for dementia.     

Recognition versus recall of briefly presented visual information: a developmental study.

Five-year-olds, as compared to adults, have displayed a striking constraint on short-term recognition memory for briefly presented visual information. In the present study, a recall paradigm was also examined to test the generality of this constraint. Additionally, we examined the possibility that forced verbal report might differentially enhance children's performance. Evidence of improved performance in children would suggest that a verbal encoding strategy, used by adults only during the recognition task, is activated in children in a recall task. Though recall memory performance of young children did surpass recognition memory levels, the same was true for adults with the relative adult-child difference remaining constant across conditions. It was concluded that processes other than verbal labeling (e.g., buffer storage, organization, retrieval) are probably more responsible for age differences in immediate memory performance than labeling, per se.     

Effects of time pressure on strategy selection and strategy execution in forced choice tests

We examined the effects of cognitive load on the strategy selection in the forced choice test (FCT) when used to detect hidden crime knowledge. Examinees (N = 120) with and without concealed knowledge from a mock crime were subjected to an FCT either under standard circumstances or cognitive load. Cognitive load was implemented through time pressure. The FCT distinguished examinees with concealed knowledge from those without better than chance in both conditions, but the counterstrategies did not differ between conditions. Further investigation revealed that time pressure did affect examinees' ability to follow their intended counterstrategy to produce randomized test patterns, which constitutes an effective counterstrategy in the FCT. Hence, time pressure lowered the success rate of effective counterstrategies, but not their incident rates. Further disambiguation of various cognitive load manipulations and their effects on strategy selection and execution is needed.     

An examination of practice effects in recognition

A study of practice effects in recognition performance is reported. In each of two experiments, different conditions of training were followed by a critical final test. In Experiment 1, a yes-no procedure was used on the critical test. During the training phase, some subjects were tested by the same method, either with or without item-by-item feedback, whereas others were given forced. choice tests. No significant changes in recognition accuracy were observed, either during the training trials or on the final test. However, feedback and experience with forced-choice tests both served to increase the bias toward positive responding. In Experiment 2, the forced-choice procedure was used on the critical final test. Either forced. choice tests or yes-no tests were given on the training lists. Again, there were no significant changes in performance. The absence of practice effects is attributed to the difficulty of identifying and implementing test-appropriate strategies.     

Serial position curves in short‐term memory: Functional equivalence across modalities

Four experiments investigated item and order memory for sequences of seen unfamiliar faces and heard nonwords. Experiments 1 and 3 found bowed serial position curves using the serial reconstruction test of order with faces and nonwords, respectively. Experiments 2 and 4 found limited recency, no primacy, and above chance performance on all items using a two‐alternative forced choice (2AFC) test of item recognition, again with faces and nonwords. These results suggest that the different serial position curves typically found using traditional paradigms for exploring visual and verbal short‐term memory are due to differences in the methods used rather than modality‐specific mechanisms.     

Transfer effects in implicit memory and consumer choice

Two experiments investigated transfer effects in implicit memory and consumer choice, using a preference judgement task. Experiment 1 examined whether it is possible to obtain priming for unfamiliar food labels. Additionally, it investigated whether the experience of seeing a brand name with a particular product type would benefit subsequent processing of the brand name when linked with a different product type. Experiment 2 examined whether changes in modality between study and test would affect priming for unfamiliar brand names. Both questions are theoretically important, as well as pertaining to practical concerns in the consumer choice literature. Experiment 1 demonstrated significant priming for unfamiliar food labels, and established that priming was unaffected by changing the product type with which the brand name was associated. In Experiment 2, priming on both auditory and visual versions of the preference judgement task was reduced by changes in modality. The results and implications are discussed in relation to consumer choice and current theories of implicit memory. Copyright © 2001 John Wiley & Sons, Ltd.