Michael F. Verde

Memory strength and the decision process in recognition memory

We investigated the role that memory strength plays in the decision process by examining the extent to which strength is used as a cue to dynamically modify recognition criteria. The study list consisted of strong and weak items, with strength a function of study duration or repetition. The recognition test list was divided into two consecutive blocks; strong items appeared in one block, weak items in the other. If the change in item strength across blocks leads to a shift in criterion, the false alarm rate should change accordingly. In four experiments, the false alarm rates did not change across blocks, even when the difference between the strong and the weak items was magnified and marked with semantic cues. However, the strength of the items in the first test block affected the false alarm rate. Thus, strength cues influence initial criterion placement but fail to induce criterion shifts following permanent and even dramatic changes in item strength. These null findings are contrasted with those in a fifth experiment, in which accuracy feedback produced dynamic criterion shifts.

Measures of sensitivity based on a single hit rate and false alarm rate: The accuracy, precision, and robustness of′,A z, andA’

Signal detection theory offers several indexes of sensitivity (d’,Az, andA’) that are appropriate for two-choice discrimination when data consist of one hit rate and one false alarm rate per condition. These measures require simplifying assumptions about how target and lure evidence is distributed. We examine three statistical properties of these indexes: accuracy (good agreement between the parameter and the sampling distribution mean), precision (small variance of the sampling distribution), and robustness (small influence of violated assumptions on accuracy). We draw several conclusions from the results. First, a variety of parameters (sample size, degree of discriminability, and magnitude of hits and false alarms) influence statistical bias in these indexes. Comparing conditions that differ in these parameters entails discrepancies that can be reduced by increasing N. Second, unequal variance of the evidence distributions produces significant bias that cannot be reduced by increasing N—a serious drawback to the use of these sensitivity indexes when variance is unknown. Finally, their relative statistical performances suggest thatAz is preferable toA’.

Type I error rates and power analyses for single-point sensitivity measures

Experiments often produce a hit rate and a false alarm rate in each of two conditions. These response rates are summarized into a single-point sensitivity measure such as d’, and t tests are conducted to test for experimental effects. Using large-scale Monte Carlo simulations, we evaluate the Type I error rates and power that result from four commonly used single-point measures: d’, A’, percent correct, and γ. We also test a newly proposed measure called γinC. For all measures, we consider several ways of handling cases in which false alarm rate = 0 or hit rate = 1. The results of our simulations indicate that power is similar for these measures but that the Type I error rates are often unacceptably high. Type I errors are minimized when the selected sensitivity measure is theoretically appropriate for the data.

The retrieval practice effect in associative recognition

Recalling an item interferes with recall of related memories. Evidence is presented that retrieval interference occurs in associative recognition as well as recall. In Experiment 1, subjects studied pairs of category exemplars. Retrieval practice followed, during which some pairs appeared in a cued recall test. A final test of associative recognition (with remember—know judgments) found lower accuracy and hit rate for nonpracticed pairs belonging to retrieval-practiced categories. In Experiment 2, subjects studied noun pairs from overlapping sets, with study duration manipulated between subjects. Retrieval practice was manipulated by presenting some members of a set in a previous block during the recognition test. With long study duration, retrieval interference was evident in both recognition and remember judgments. With short study duration, it appeared only in remember judgments. These results support a dual-process account in which retrieval interference is specific to recollection and becomes evident in recognition performance only when recollection is sufficiently dominant.

ROC curves show that the revelation effect is not a single phenomenon

The revelation effect describes the increased tendency to call itemsold when a recognition judgment is preceded by an incidental task. In theory, the effect could come about either from a more liberal response bias or from a change in underlying memory sensitivity. Using analyses of receiver-operating characteristic curves, we show that the revelation effect occurs for each of these reasons, but under different empirical conditions. A shift in response bias fully accounts for the revelation effect when revealed items are unrelated to the subsequent recognition probes. However, a change in memory sensitivity contributes to the effect when revealed items are identical to the recognition probes. Thus, the revelation effect encompasses at least two distinct phenomena.

Retrieval-Induced Forgetting and Inhibition: A Critical Review

70 6.3 Summary 73 7. Conclusion 73 Abstract The influence of classic interference theories on contemporary thinking about recall is embodied in the principle of competitor interference, which suggests that forgetting is a direct result of competition among memories associated with a retrieval cue. The inhibition theory of forgetting (Anderson, 2003; Anderson & Bjork, 1994) represents a major departure from the interference tradition in suggesting that an active inhibition mech- anism, rather than competition among memories, causes forgetting. This review offers a critical evaluation of the empirical support and the theoret- ical underpinnings of the case for inhibition and against competitor interference.

Retrieval-induced forgetting in recognition is absent under time pressure

We examined retrieval-induced forgetting (RIF) in recognition from a dual-process perspective, which suggests that recognition depends on the outputs of a fast familiarity process and a slower recollection process. In order to determine the locus of the RIF effect, we manipulated the availability of recollection at retrieval via response deadlines. The standard RIF effect was observed in a self-paced test but was absent in a speeded test, in which judgments presumably depended on familiarity more than recollection. The findings suggested that RIF specifically affects recollection. This may be consistent with a context-specific view of retrieval inhibition.

The List-Strength Effect in Recall: Relative-Strength Competition and Retrieval Inhibition May both Contribute to Forgetting.

According to the principle of relative-strength competition, stronger items in memory block the retrieval of weaker items. This principle, integral to many theories of forgetting over the years, derives much of its support from the list-strength effect (LSE), in which strengthening some items in a study list makes it more difficult to recall other items. Work in the retrieval-induced forgetting literature has challenged the existence of relative-strength competition, 1st by offering many examples of a null LSE and 2nd by proposing that extant observations of the LSE can be explained by retrieval inhibition. In the present study, a series of experiments produced a robust LSE in cued recall under conditions meant to control the contribution of retrieval inhibition. Simulations of the SAM-REM model of recall (K. J. Malmberg & R. M. Shiffrin, 2005) showed that a model based on relative-strength competition can accommodate both the presence and absence of an LSE. The empirical results and model simulations together make a case for the role of strength-based competition in forgetting.

The SDT model of belief bias: complexity, time, and cognitive ability mediate the effects of believability.

When people evaluate conclusions, they are often influenced by prior beliefs. Prevalent theories claim that belief bias affects the quality of syllogistic reasoning. However, recent work by Dube, Rotello, and Heit (2010) has suggested that belief bias may be a simple response bias. In Experiment 1, receiver operating characteristic analysis revealed that believability affected accuracy for complex but not for simple syllogisms. In Experiment 2, the effect of believability on accuracy disappeared when judgments were made under time pressure and with participants low in cognitive capacity. The observed effects on reasoning accuracy indicate that beliefs influence more than response bias when conditions are conducive to the use of certain reasoning strategies. The findings also underscore the need to consider individual differences in reasoning.

Associative interference in recognition memory: A dual-process account

Associative interference from overlapping word pairs (A-B, A-D) reduces recall but has inconsistent effects on recognition. A dual-process account suggests that interference conditions reduce recollection but increase familiarity. This is predicted to increase recognition false alarms but have variable effects on recognition hits, depending on the relative contribution of recollection and familiarity. In three experiments that varied materials (sentences or random nouns) and test type (associative or pair recognition), interference conditions always increased recognition false alarms, but sometimes increased and sometimes decreased recognition hits. However, remember hits always decreased and know hits always increased with interference, patterns predicted of the recollection and familiarity processes, respectively. According to the dual-process view, a manipulation that affects the component processes in opposite ways can produce inconsistent patterns of recognition performance as the relative contribution of recollection and familiarity changes across tasks.