Hierarchical single- and dual-process models of recognition memory

Recognition memory is commonly modeled as either a single, continuous process within the theory of signal detection, or with two-process models such as Yonelinas’ dual-process model. Previous attempts to determine which model provides a better account of the data have relied on fitting the models to data that are averaged over items. Because such averaging distorts conclusions, we develop and compare hierarchical versions of competing single and dual-process models that account for item variability. The dual-process model provides a superior account of a typical data set when models are compared with the deviance information criterion. Parameters of the dual-process model are highly correlated, however, suggesting that a single-process model may exist that can provide a better account of the data.     

Illusory recollection and dual-process models of recognition memory

Higham and Vokey (2000, Exps.1 & 3)demonstrated that a slight increase in the display duration of a briefly presented word prior to displaying it in the clear for a recognition response increased the bias to respond “old”. In the current research, three experiments investigated the phenomenology associated with this illusion of memory using the standard remember-know procedure and a new, independent-scales methodology. Contrary to expectations based on the fluency heuristic, which predicts effects of display duration on subjective familiarity only, the results indicated that the illusion was reported as both familiarity and recollection. Furthermore, manipulations of prime duration induced reports of false recollection in all experiments. The results—in particular, the implications of illusory recollection—are discussed in terms of dual-process, fuzzy-trace, two-criteria signal detection models and attribution models of recognition memory.     

How to say "no" to a nonword: a leaky competing accumulator model of lexical decision

We describe a leaky competing accumulator (LCA) model of the lexical decision task that can be used as a response/decision module for any computational model of word recognition. The LCA model uses evidence for a word, operationalized as some measure of lexical activity, as input to the YES decision node. Input to the NO decision node is simply a constant value minus evidence for a word. In this way, evidence for a nonword is a function of time from stimulus onset (as in standard deadline models) modulated by lexical activity via the competitive dynamics of the LCA. We propose a simple mechanism for determining the value of this constant online during the first trials of a lexical decision experiment, such that the model can rapidly optimize speed and accuracy in discriminating words from nonwords. Further optimization is achieved via trial-by-trial adjustments in response criteria as a function of task demands and list context. We show that the LCA model can simulate mean response times and response distributions for correct and incorrect YES and NO decisions for a number of benchmark experiments that have been shown to be fatal for deadline models of lexical decision. Finally, using lexical activity calculated by a computational model of word recognition as input to the LCA decision module, we provide the first item-level simulation of both word and nonword responses in a large-scale database.     

Ease of access to list items in short-term memory depends on the order of the recognition probes

We report data from 4 experiments using a recognition design with multiple probes to be matched to specific study positions. Items could be accessed rapidly, independent of set size, when the test order matched the study order (forward condition). When the order of testing was random, backward, or in a prelearned irregular sequence (reordered conditions), the classic Sternberg result was obtained: Response times were slow and increased linearly with set size. A number of explanations for forward-condition facilitation were ruled out, such as the predictability of the study order (Experiment 2), the predictability of the probe order (Experiment 1), the covariation of study and test orders (Experiments 1, 2, and 4), processes of probe encoding and perception that did not rely on STM access (Experiments 1, 2, and 4), specific support of the forward condition by articulatory processes (Experiment 3), or condition-dependent strategic differences (Experiment 4). More detailed analyses demonstrated that fast forward responses could not be accounted for by the effects of input position and output position that modulated random responses, effects that did account for the slower responses of the reordered conditions (Experiments 1, 3, and 4). A final analysis of probe-to-probe transitions as a function of encoding distance revealed a sizeable single-step benefit in the random condition. We concluded that STM representations were serial rather than spatial and that forward probes benefited from their serial adjacency.     

Individual differences in working memory capacity and dual-process theories of the mind

Dual-process theories of the mind are ubiquitous in psychology. A central principle of these theories is that behavior is determined by the interplay of automatic and controlled processing. In this article, the authors examine individual differences in the capacity to control attention as a major contributor to differences in working memory capacity (WMC). The authors discuss the enormous implications of this individual difference for a host of dual-process theories in social, personality, cognitive, and clinical psychology. In addition, the authors propose several new areas of investigation that derive directly from applying the concept of WMC to dual-process theories of the mind.     

The generation effect: a test between single- and multifactor theories

Single- and multifactor accounts of the generation effect (better memory for internally generated items than for externally presented items) were tested. Single-factor theories suggest that generation induces either stimulus-response relational processing or response-oriented processing. Multifactor theories suggest that generation induces both types of processing. In the first three experiments subjects either read or generated responses, and the degree of categorical structure within the list was manipulated. When categorical structure was minimal, large generation effects were observed for free recall and recognition, but not for cued recall. When categorical structure was high, however, a generation effect was observed for cued recall but not for recognition or free recall. A fourth experiment was performed to eliminate an uninteresting interpretation of the results. It is argued that a multifactor account is needed to explain these findings.     

Homogeneity computation: How interitem similarity in visual short-term memory alters recognition

Visual short-term recognition memory for multiple stimuli is strongly influenced by the study items’ similarity to one another—that is, by their homogeneity. However, the mechanism responsible for this homogeneity effect has remained unclear. We evaluated competing explanations of this effect, using controlled sets of Gabor patches as study items and probe stimuli. Our results, based on recognition memory for spatial frequency, rule out the possibility that the homogeneity effect arises because similar study items are encoded and/or maintained with higher fidelity in memory than dissimilar study items are. Instead, our results support the hypothesis that the homogeneity effect reflects trial-by-trial comparisons of study items, which generate a homogeneity signal. This homogeneity signal modulates recognition performance through an adjustment of the subject’s decision criterion. Additionally, it seems the homogeneity signal is computed prior to the presentation of the probe stimulus, by evaluating the familiarity of each new stimulus with respect to the items already in memory. This suggests that recognition-like processes operate not only on the probe stimulus, but on study items as well.     

Models of recognition: A review of arguments in favor of a dual-process account

The majority of computationally specified models of recognition memory have been based on a single-process interpretation, claiming that familiarity is the only influence on recognition. There is increasing evidence that recognition is, in fact, based on two processes: recollection and familiarity. This article reviews the current state of the evidence for dual-process models, including the usefulness of the remember/know paradigm, and interprets the relevant results in terms of the source of activation confusion (SAC) model of memory. We argue that the evidence from each of the areas we discuss, when combined, presents a strong case that inclusion of a recollection process is necessary. Given this conclusion, we also argue that the dual-process claim that the recollection process is always available is, in fact, more parsimonious than the single-process claim that the recollection process is used only in certain paradigms. The value of a well-specified process model such as the SAC model is discussed with regard to other types of dual-process models.     

Activation and binding in verbal working memory: a dual-process model for the recognition of nonwords

The article presents a mathematical model of short-term recognition based on dual-process models and the three-component theory of working memory [Oberauer, K. (2002). Access to information in working memory: Exploring the focus of attention. Journal of Experimental Psychology: Learning, Memory, and Cognition, 28, 411-421]. Familiarity arises from activated representations in long-term memory, ignoring their relations; recollection retrieves bindings in the capacity-limited component of working memory. In three experiments participants encoded two short lists of nonwords for immediate recognition, one of which was then cued as irrelevant. Probes from the irrelevant list were rejected more slowly than new probes; this was also found with probes recombining letters of irrelevant nonwords, suggesting that familiarity arises from individual letters independent of their relations. When asked to accept probes whose letters were all in the relevant list, regardless of their conjunction, participants accepted probes preserving the original conjunctions faster than recombinations, showing that recollection accessed feature bindings automatically. The model fit the data best when familiarity depended only on matching letters, whereas recollection used binding information.     

How semantic content of stimuli works on episodic memory processes in negative schizophrenia: Evidence from picture recognition

IntroductionEven though episodic memory is impaired in schizophrenia, semantic processing strategies can improve patients’ performance. However, it is less clear if negative schizophrenia patients can benefit from semantic strategies, and if both familiarity and recollection processes can be enhanced in patients with schizophrenia.ObjectiveThe aim of this study was to investigate the possibility for negative schizophrenia patients to enhance their familiarity and/or recollection processes in the presence of concrete images.MethodA recognition memory task using concrete versus abstract images as stimuli was designed to assess the performance of schizophrenia patients for single item recognition and the recollection of spatial context, allowing us to calculate the estimates of familiarity and recollection processes. Thirty-six patients with schizophrenia and 18 healthy individuals participated to the study. Schizophrenia patients were divided into two groups according to their scores on the negative scale of the Positive and Negative Syndrome Scale for Schizophrenia (PANSS).ResultsResults showed that, while healthy participants enhanced their recollection estimates in the presence of concrete images, both schizophrenia groups could enhance their familiarity estimates.ConclusionSemantic strategies are helpful to promote successful familiarity process in schizophrenia patients, independently from clinical dimension of negativity. However, recollection process seems not to respond to such strategies.     

Word frequency and receiver operating characteristic curves in recognition memory: evidence for a dual-process interpretation

Dual-process models of the word-frequency mirror effect posit that low-frequency words are recollected more often than high-frequency words, producing the hit rate differences in the word-frequency effect, whereas high-frequency words are more familiar, producing the false-alarm-rate differences. In this pair of experiments, the authors demonstrate that the analysis of receiver operating characteristic (ROC) curves provides critical information in support of this interpretation. Specifically, when participants were required to discriminate between studied nouns and their plurality reversed complements, the ROC curve was accurately described by a threshold model that is consistent with recollection-based recognition. Further, the plurality discrimination ROC curves showed characteristics consistent with the interpretation that participants recollected low-frequency items more than high-frequency items.     

The contribution of recollection and familiarity to recognition and source-memory judgments: a formal dual-process model and an analysis of receiver operating characteristics

A formal dual-process model that assumes that memory judgments can be based on a threshold recollection process and a signal-detection-based familiarity process is proposed to account for both recognition and source-memory performance. The model was tested in 4 experiments by examining recognition and source-memory receiver operating characteristics (ROCs). In agreement with the predictions of the model, recognition and source memory dissociated in certain conditions. Recognition ROCs were curvilinear in probability space and relatively linear in z-space, as expected if recollection and familiarity contributed to performance. In contrast, source ROCs typically were linear and exhibited a pronounced U shape in z-space, as expected if performance primarily relied on recollection. However, in conditions in which familiarity was clearly indicative of an item's source, the source ROC became curvilinear, suggesting that participants could use familiarity as a basis for source judgments. Several alternative models, including the unequal-variance signal-detection model, were found to be inconsistent with the ROC data.     

Cultural psychology of surprise: holistic theories and recognition of contradiction

The authors tested the hypothesis that East Asians, because of their holistic reasoning, take contradiction and inconsistency for granted and consequently are less likely than Americans to experience surprise. Studies 1 and 2 showed that Korean participants displayed less surprise and greater hindsight bias than American participants did when a target's behavior contradicted their expectations. Studies 3 and 4 further demonstrated that even when contradiction was created in highly explicit ways, Korean participants experienced little surprise, whereas American participants reported substantial surprise. We discuss the implications of these findings for various issues, including the psychology of conviction, cognitive dissonance, and the development of science.     

Just say no (to stereotyping): effects of training in the negation of stereotypic associations on stereotype activation

The primary aim of the present research was to examine the effect of training in negating stereotype associations on stereotype activation. Across 3 studies, participants received practice in negating stereotypes related to skinhead and racial categories. The subsequent automatic activation of stereotypes was measured using either a primed Stroop task (Studies I and 2) or a person categorization task (Study 3). The results demonstrate that when receiving no training or training in a nontarget category stereotype, participants exhibited spontaneous stereotype activation. After receiving an extensive amount of training related to a specific category, however, participants demonstrated reduced stereotype activation. The results from the training task provide further evidence for the impact of practice on participants' proficiency in negating stereotypes.     

Children's serial recall errors: implications for theories of short-term memory development

Three experiments examined developmental changes in serial recall of lists of 6 letters, with errors classified as movements, omissions, intrusions, or repetitions. In Experiments 1 and 2, developmental differences between groups of children aged from 7 to 11 years and adults were found in the pattern of serial recall errors. The errors of older participants were more likely to be movements than were those of younger participants, who made more intrusions and omissions. The number of repetition errors did not change with age, and this finding is interpreted in terms of a developmentally invariant postoutput response inhibition process. This interpretation was supported by the findings of Experiment 3, which measured levels of response inhibition in 7-, 9-, and 11-year-olds by comparing recall of lists with and without repeated items. Response inhibition remained developmentally invariant, although older children showed greater response facilitation (improved correct recall of adjacent repeated items). Group differences in the patterns of other errors are accounted for in terms of developmental changes in levels of output forgetting and changes in the efficiency of temporal encoding processes.     

The effect of feature frequency on short-term recognition memory

We report two experiments using Sternberg's (1969) multitrial recognition-memory paradigm. We used colored shapes as stimuli and manipulated the frequency of the shapes (but not of the colors) across trials. For lures containing an extralist shape (i.e., a shape not studied in the current study list), responses were faster if the shape had occurred infrequently than if it had occurred frequently in the preceding trials. For lures containing an extralist color and a studied shape, by contrast, the frequency of the shape in the preceding trials was irrelevant. We conclude that correct rejections depend solely on contradictory evidence. Furthermore, low-frequency target items were recognized more easily than high-frequency targets. Both the interaction of frequency with the features of the lures and the main effect of frequency for the targets are problematic for current accounts of recognition.     

Effects of sleep deprivation on short-term recognition memory.

A probe-recognition short-term memory paradigm was used to inquire into the precise effects of sleep deprivation on human memory. It was found that recognition performance, as measured by d', was generally impaired for each subjects after 24 hr of sleep deprivation. While d' was shown to decrease exponentially as the number of items intervening between the target and the probe increased, this decay rate was not affected by sleep loss. In addition there was confirmation of a previously observed increase in the positive skewness of reaction times after wakefulness. The data were consistent with the hypothesis that sleep deprivation increases the occurrence of lapses, periods of lowered reactive capacity, which prevent the encoding of items in short-term memory.