Hypermnesia: The role of multiple retrieval cues

We demonstrate that encoding multiple cues enhances hypermnesia. College students were presented with 36 (Experiment 1) or 60 (Experiments 2 and 3) sets of words and were asked to encode the sets under single- or multiple-cue conditions. In the single-cue conditions, each set consisted of a cue and a target. In the multiple-cue conditions, each set consisted of three cues and a target. Following the presentation of the word sets, the participants received either three cued recall tests (Experiments 1 and 2) or three free recall tests (Experiment 3). With this manipulation, we observed greater hypermnesia in the multiple-cue conditions than in the single-cue conditions. Furthermore, the greater hypermnesic recall resulted from increased reminiscence rather than reduced intertest forgetting. The present findings support the hypothesis that the availability of multiple retrieval cues plays an important role in hypermnesia.     

Hypermnesia and the Role of Delay between Study and Test

Hypermnesia is increased recall across repeated tests in the absence of any further study opportunities. Although over the years many factors have been identified that influence hypermnesia, to date not much is known about the role of delay between study and test for the effect. This study addressed the issue in four experiments. Employing both words and pictures as study material, we compared hypermnesia after shorter delay (3 min or 11.5 min) and longer delay (24 h or 1 week) between study and test. Recall occurred over three successive tests, using both free recall (Experiments 1, 2, and 4) and forced recall testing (Experiment 3). In forced recall tests, subjects are instructed to recall as many items as possible, but if unable to remember all studied items, to fill in the remaining spaces with their best guesses. With free recall testing, hypermnesia increased with delay and the effect was driven mainly by reduced item losses between tests. These results suggest a link between hypermnesia and the testing effect, which shows that demanding retrieval practice, as it happens after longer delay, can improve recall by reducing the forgetting of the practiced items. In contrast, with forced recall testing, hypermnesia decreased with delay and was even absent after longer delay. The findings indicate that recall format can influence hypermnesia and different mechanisms may mediate the effects of repeated testing in the two recall conditions.     

Strengthening concept learning by repeated testing

The aim of this study was to examine whether repeated testing with feedback benefits learning compared to rereading of introductory psychology key‐concepts in an educational context. The testing effect was examined immediately after practice, after 18 days, and at a five‐week delay in a sample of undergraduate students (n = 83). The results revealed that repeated testing with feedback significantly enhanced learning compared to rereading at all delays, demonstrating that repeated retrieval enhances retention compared to repeated encoding in the short‐ and the long‐term. In addition, the effect of repeated testing was beneficial for students irrespectively of working memory capacity. It is argued that teaching methods involving repeated retrieval are important to consider by the educational system.     

Drug discrimination: stimulus control during repeated testing in extinction

Rats were trained, under a two-lever drug-discrimination procedure, to respond differentially depending upon whether lorazepam (1.0 mg/kg) or no injection had been administered before the session. Responses on the appropriate lever produced a food pellet under a modified fixed-ratio (FR) 10 schedule, in which the 10 responses had to be emitted consecutively. In reinforcement tests, completing an FR 10 on either lever produced a pellet. In extinction tests, stimulus changes paired with reinforcement occurred but no pellet was delivered. Training sessions were conducted between test sessions. Each of four extinction phases consisted of six tests preceded by one stimulus (e.g., lorazepam). Repeated exposures to extinction reduced response rates for all rats, but stimulus control, as inferred from either percentage of total responses or percentage of total FR 10s on the drug-appropriate lever, remained high. The percentage of total FR 10s measure was less subject to skewing under low-rate conditions than was the percentage of total responses measure and provided an evaluation of stimulus control in terms of meeting the consecutive response contingency. These results demonstrate a level of independence between response rate and stimulus control in drug discrimination, which has positive implications for the validity of interpreting discriminative effects of novel test conditions in well-trained animals, even when overall response rates are low.     

Hypermnesia: Age-related differences between young and older adults

Hypermnesia is a net improvement in memory performance that occurs across tests in a multitest paradigm with only one study session. Our goal was to identify possible age-related differences in hypermnesic recall. We observed hypermnesia for young adults using verbal (Experiment 1) as well as pictorial (Experiment 2) material, but no hypermnesia for older adults in either experiment. We found no age-related difference in reminiscence (Experiments 1 and 2), though there was a substantial difference in intertest forgetting (Experiments 1 and 2). Older, relative to young, adults produced more forgetting, most of which occurred between Tests 1 and 2 (Experiments 1 and 2). Furthermore, older, relative to young, adults produced more intrusions. We failed to identify a relationship between intrusions and intertest forgetting. We suggest that the age-related difference in intertest forgetting may be due to less efficient reinstatement of cues at test by older adults. The present findings reveal that intertest forgetting plays a critical role in hypermnesic recall, particularly for older adults.     

Hypermnesia for high-imagery words: The effects of interpolated tasks

The purpose of this study was to determine whether hypermnesia (improved net recall over time) can be differentially affected by manipulating the nature of tasks performed during the intervals between successive recall trials. In Experiment 1, all subjects were asked to imaginally encode separate words and were tested three times for recall. The control group (no interpolated task) produced the hypermnesia effect. Both groups performing interpolated tasks showed significantly lower recall. A second experiment was conducted in order to replicate these results and to examine the effects of intertest rehearsal on hypermnesia. In Experiment 2, subjects were asked to encode pairs of words using interactive-imagery instructions. Six different interpolated task conditions were employed, varying in the degree to which subsystems of working memory were used. Groups performing imaginal interpolated tasks showed no hypermnesia, whereas those performing nonimaginal tasks did. These findings suggest that access to working memory (see Baddeley, 1986) is not necessary for hypermnesia.     

Hypermnesia: A further examination of age differences between young and older adults

Previous studies that examined age differences in hypermnesia reported inconsistent results. The present experiment investigated whether the different study materials in these studies were responsible for the inconsistency. In particular, the present experiment examined whether the use of a video, as opposed to words and pictures, would eliminate previously reported age differences in hypermnesia. Fifteen college students and 15 older adults viewed a 3‐minute video clip followed by two free‐recall tests. The results indicated that older adults, as a whole, did not show hypermnesia. However, when older adults were divided into low and high memory groups based on test 1 performance, the high memory group showed hypermnesia whereas the low memory group did not show hypermnesia. The older adults in the low memory group were significantly older than the older adults in the high memory group – indicating that hypermnesia is inversely related to age in older adults. Reminiscence did not show an age‐related difference in either the low or high memory group whereas inter‐test forgetting did show an age difference in the low memory group. As expected, older adults showed greater inter‐test forgetting than young adults in the low memory group. Findings from the present experiment suggest that video produces a pattern of results that is similar to the patterns obtained when words and pictures are used as study material. Thus, it appears that the nature of study material is not the source of inconsistency across the previous studies.     

SNOOP: A program for demonstrating the consequences of premature and repeated null hypothesis testing

The ease with which data can be collected and analyzed via personal computer makes it potentially attractive to “peek” at the data before a target sample size is achieved. This tactic might seem appealing because data collection could be stopped early, which would save valuable resources, if a peek revealed a significant effect. Unfortunately, such data snooping comes with a cost. When the null hypothesis is true, the Type I error rate is inflated, sometimes quite substantially. If the null hypothesis is false, premature significance testing leads to inflated estimates of power and effect size. This program provides simulation results for a wide variety of premature and repeated null hypothesis testing scenarios. It gives researchers the ability to know in advance the consequences of data peeking so that appropriate corrective action can be taken.     

The dark side of testing memory: repeated retrieval can enhance eyewitness suggestibility

Eyewitnesses typically recount their experiences many times before trial. Such repeated retrieval can enhance memory retention of the witnessed event. However, recent studies (e.g., Chan, Thomas, & Bulevich, 2009) have found that initial retrieval can exacerbate eyewitness suggestibility to later misleading information--a finding termed retrieval-enhanced suggestibility (RES). Here we examined the influence of multiple retrieval attempts on eyewitness suggestibility to subsequent misinformation. In four experiments, we systematically varied the number of initial tests taken (between zero and six), the delay between initial testing and misinformation exposure (~30 min or 1 week), and whether initial testing was manipulated between- or within-subjects. University undergraduate students were used as participants. Overall, we found that eyewitness suggestibility increased as the number of initial tests increased, but this RES effect was qualified by the delay and by whether initial testing occurred in a within- or between-subjects manner. Specifically, the within-subjects RES effect was smaller than the between-subjects RES effect, possibly because of the influence of retrieval-induced forgetting/facilitation (Chan, 2009) when initial testing was manipulated within subjects. Moreover, consistent with the testing effect literature (Roediger & Karpicke, 2006), the benefits of repeated testing on later memory were stronger after a 1-week delay than after a 30-min delay, thus reducing the negative impact of RES in long-term situations. These findings suggest that conditions that are likely to occur in criminal investigations can either increase (repeated testing) or reduce (delay) the influence of RES, thus further demonstrating the complex relationship between eyewitness memory and repeated retrieval.     

Extinguishing conditioned inhibition in flavour-aversion learning: Effects of repeated testing and extinction of the excitatory element

Three conditioned inhibition experiments using an A+/AX- design are reported in which lithium-mediated excitatory conditioning occurred to distinctive environmental stimuli and inhibitory conditioning to a vinegar flavour. Increased vinegar preferences were observed (i.e., conditioned inhibition) in each experiment, and these preferences extinguished with repeated testing as well as following extinction of the excitatory element. Vinegar preferences could be reinstated through reconditioning of the extinguished excitatory stimulus. These experiments speak to the status of inhibitory responding as a “slave” process to conditioned excitation.     

Untangling the benefits of multiple study opportunities and repeated testing for cued recall

Spacing multiple study opportunities apart from one another is known by psychologists to be a highly effective study method (see Dempster, 1996). This study examines whether including tests during study would produce practical benefits for learning beyond that provided by distributed study alone. In addition, spacing of both study and test (massed, uniform distributed, and expanding distributed) is investigated. To‐be‐remembered information was repeated with a single learning session (Experiment 1), reviewed immediately after initial learning (Experiment 2), or reviewed days after initial learning (Experiments 3 and 4). As expected, large distributed practice effects were shown across experiments. In addition to these effects, testing produced significant benefits for learning in all four experiments, which were of moderate or large size (Cohen's d of 0.52 to 1.30) for three experiments. Expanding test spacing, however, did not independently benefit learning in any of the learning situations studied. Educators should take advantage of the large benefits that distributed study and testing have on learning by spacing multiple tests of information within learning sessions and by distributing tests across multiple review sessions. Copyright © 2000 John Wiley & Sons, Ltd.     

Assessment of remote memory: Validation of the television test by repeated testing during a 7-year period

Remote memory for former, one-season television programs was assessed on four different occasions during 7 years. Each test yielded a forgetting curve that was primarily monotonic and linear. In addition, the forgetting curve obtained by the first application of this test in 1973 was largely recapitulated by the three later applications of the test. These findings, together with new information concerning the equivalence of items from different time periods, provide strong evidence that the television test validly measures remote memory.     

Differentiated forgetting rates of spatial knowledge in humans in the absence of repeated testing

Spatial knowledge, necessary for efficient navigation, comprises route knowledge (memory of the landmarks along a route) and survey knowledge (map-like). Available data on the retention in humans of spatial knowledge show that this does not decline systematically over months or years. Here, two groups of participants elaborated route and survey knowledge during navigation in a complex virtual environment before performing route and survey tasks. Both groups were tested 5 minutes after learning and 3 months later, while one group was also tested 1 week and 1 month later (repeated testing). Performance was similar in both groups on the first testing session, remained stable in the repeated tested group, but decreased in the non-repeated tested group, especially on route tasks. These results are the first to reveal a substantial and selective decline of spatial knowledge, occurring only if there is no possibility of reactivating knowledge along repeated testing.     

Differentiated forgetting rates of spatial knowledge in humans in the absence of repeated testing

Spatial knowledge, necessary for efficient navigation, comprises route knowledge (memory of the landmarks along a route) and survey knowledge (map-like). Available data on the retention in humans of spatial knowledge show that this does not decline systematically over months or years. Here, two groups of participants elaborated route and survey knowledge during navigation in a complex virtual environment before performing route and survey tasks. Both groups were tested 5 minutes after learning and 3 months later, while one group was also tested 1 week and 1 month later (repeated testing). Performance was similar in both groups on the first testing session, remained stable in the repeated tested group, but decreased in the non-repeated tested group, especially on route tasks. These results are the first to reveal a substantial and selective decline of spatial knowledge, occurring only if there is no possibility of reactivating knowledge along repeated testing.     

Win some, lose some: Hypermnesia for actions reflects increased item-specific processing

Memory for simple action phrases (e.g., “Break a match”) improves when subjects perform the actions at study. The relative contribution of item-specific and relational processing to this enactment effect has been an issue of considerable debate. It was addressed in the present study by examining hypermnesia in a multiple-test free recall paradigm, -based on the assumptions that itemspecific processing increases the probability of intertest gains and relational processing protects against intertest forgetting (e.g., Burns, 1993; Klein, Loftus, Kihlstrom, & Aseron, 1989). It was found that the enactment condition produced both significantly more gains and more losses than did the nonenactment condition, resulting in a net gain (hypermnesia) for the enactment condition. The results suggest that enactment promotes item-specific processing at the expense of relational processing.     

"HIV testing is so gay": the role of masculine gender role conformity in HIV testing among men who have sex with men

Men who have sex with men (MSM) account for more than half of all new cases of HIV infection in the United States. Yet, many MSM are unaware of their HIV serostatus. Consistent with research indicating that gender role conformity impacts health behaviors, this study examined how masculine norms may influence HIV testing among MSM in the United States. Data from 170 self-identified MSM (age M = 46.45, SD = 12.18) of self-reported negative or unknown HIV serostatus living in the United States were used in this study. About half (52%) of participants reported that they had been tested for HIV within the past 12 months; 48% reported that they had not. Logistic regression was used to examine the association between domains of masculine gender role conformity and HIV testing within the past 12 months, controlling for number of sexual partners in the last 12 months. The masculine norm of heterosexual self-presentation (i.e., desire to be perceived by others as heterosexual) was negatively associated with HIV testing (B = -0.74, SE B = 0.36, O.R. = 0.48, 95% CI [0.24, 0.96]), after controlling for the effect of number of sexual partners. Psychologists and other health professionals may remain mindful of potential implications of HIV testing among MSM, including potential for MSM to view HIV testing as an "outing" procedure.