Paired-associate Lists Research Articles

Adverse interaction effects of chronic and acute sleep deficits on spatial working memory but not on verbal working memory or declarative memory.

The accumulation of chronic sleep deficits combined with acute sleep loss is common in shift workers and increases the risk of errors and accidents. We investigated single and combined effects of chronic and acute sleep loss and recovery sleep on working memory performance (N-back task) and on overnight declarative memory recall (paired-associate lists) in 36 healthy participants. After baseline measurements, the chronic sleep restriction group (n=21; mean [SD] age 26[4]years) underwent 5nights of sleep restriction (5-hr time in bed [TIB]), whereas the control group (n=15; mean [SD] age 28[6]years) had 8-hr TIB during those nights. Afterwards, both groups spent 1night with 8-hr TIB prior to acute sleep deprivation for 38hr, and a final recovery night (10-hr TIB). Chronic sleep restriction decreased spatial N-back performance compared to baseline (omissions: p = .001; sensitivity: p = .012), but not letter N-back performance or word-pair recall. Acute sleep deprivation impaired spatial N-back performance more in the chronic sleep restriction group than in the control group (interaction between group and time awake: p ≤ .02). No group differences during acute sleep loss appeared in letter N-back performance or word recall. It is concluded that chronic sleep loss, even when followed by a night of recovery sleep, increases the vulnerability to impairments in spatial working memory during subsequent acute sleep loss. Verbal working memory and declarative memory were not affected by restricted sleep.

Different reactivation procedures enable or prevent episodic memory updating.

The present study asked whether the specific method of reactivation modulates the impact of new learning on reactivated episodic memories. The study consisted of three sessions that were spaced 48 hr apart. It used an ABAC paradigm that allowed for the simultaneous assessment of retroactive interference (RI: reduced A-B recall after A-C learning) and intrusions from C into A-B recall. In Session 1, participants learned a list of paired-associates A-B. In Session 2, memory for A-B was reactivated or not and then participants either learned a second list of paired-associates A-C or completed a control task. Three different reminder conditions were compared to a no-reminder condition: a test condition, in which participants were asked to recall B in response to A, a restudy condition, in which A-B pairs were presented again for study, and a cue-word only reminder condition, in which A cues were presented in an unrelated rating task. In Session 3, recall of A-B was tested. Moderate or indirect reactivation of A-B (presentation of cue-words only) resulted in high RI effects and intrusion rates, whereas strong and direct reactivation (test and restudy) drastically reduced these effects. We suggest that direct reactivation of A-B before A-C learning strengthens memory and draws attention to list differences, thereby enhancing list segregation, and reducing memory updating.

The immediate benefits and long-term consequences of briefly presented masked primes on episodic recollection

Abstract Within-trial priming paradigms have been widely used to measure lexical retrieval and familiarity-based processes in speeded pronunciation, perceptual identification, lexical decision, lexical retrieval, and episodic recognition tasks. Here, we introduce a novel within-trial priming paradigm to examine cued recall, which is considered a more recollection-based task. In each experiment, participants initially studied a list of paired-associates (e.g., BADGE-gold). During each recall test trial, 500 ms after the onset of the stimulus cue (BADGE-??????), a pattern-masked prime was briefly presented for either 48 ms or 125 ms, with the task to recall the word (e.g., gold) paired with the cue (BADGE). Across seven experiments, the primes were identical (gold), semantically related (silver), orthographically related (good), or unrelated (chair) to the to-be-recalled response item (gold). The results consistently indicated that the masked identity primes benefited immediate recall at both the 48 ms and 125 ms durations. There was no benefit from the orthographically related prime condition, suggesting that participants were not using partial letter information as an additional cue for memory retrieval. Semantically related primes only produced a benefit in immediate recall at the 125 ms prime duration. Delayed cued recall performance indicated that the facilitatory priming effects observed in immediate recall were eliminated. In addition, results from conditional analyses suggest that the benefits of retrieval in an immediate recall condition are reversed in the delayed recall condition. We consider multiple interpretations of these delayed recall results and argue that the results are in part due to priming influencing an activation-based mechanism in the immediate recall task, which decreases the retrieval demands for the response item to the paired associate cue, and hence, decreases the long-term benefits of retrieval practice.

Semantic priming, not repetition priming, is to blame for false hearing.

Contextual and sensory information are combined in speech perception. Conflict between the two can lead to false hearing, defined as a high-confidence misidentification of a spoken word. Rogers, Jacoby, and Sommers (Psychology and Aging, 27(1), 33-45, 2012) found that older adults are more susceptible to false hearing than are young adults, using a combination of semantic priming and repetition priming to create context. In this study, the type of context (repetition vs. sematic priming) responsible for false hearing was examined. Older and young adult participants read and listened to a list of paired associates (e.g., ROW-BOAT) and were told to remember the pairs for a later memory test. Following the memory test, participants identified words masked in noise that were preceded by a cue word in the clear. Targets were semantically associated to the cue (e.g., ROW-BOAT), unrelated to the cue (e.g., JAW-PASS), or phonologically related to a semantic associate of the cue (e.g., ROW-GOAT). How often each cue word and its paired associate were presented prior to the memory test was manipulated (0, 3, or 5 times) to test effects of repetition priming. Results showed repetitions had no effect on rates of context-based listening or false hearing. However, repetition did significantly increase sensory information as a basis for metacognitive judgments in young and older adults. This pattern suggests that semantic priming dominates as the basis for false hearing and highlights context and sensory information operating as qualitatively different bases for listening and metacognition.

Further boundary conditions for the effects of perceptual disfluency on judgments of learning

The experience of fluency while learning might bias students’ metacognitive judgments of learning (JOLs) and impair the efficacy of their study behaviors. In the present experiments, we examined whether perceptual fluency affects JOLs (1) when people only experience one level of fluency, (2) when item relatedness is also available as a cue, and (3) across study-test trials. Participants studied a list of paired associates over two study-test trials and made JOLs for each item after studying it. We varied the perceptual fluency of the memory materials by making the font easy (fluent) or difficult (disfluent) to read. We also varied whether we manipulated the perceptual fluency of the items between-participants or within-participants and whether other memory factors—item relatedness and study time—were available for participants to use to inform their JOLs. We were only able to obtain effects of perceptual fluency on JOLs when we manipulated fluency within-participants and eliminated item relatedness as a cue for JOLs. The present results indicate that some effects of perceptual fluency on JOLs are not robust and might only occur under limited—and somewhat contrived—conditions. Therefore, these effects might be unlikely to bias students’ JOLs in actual learning situations.

Audiovisual spoken word training can promote or impede auditory-only perceptual learning: prelingually deafened adults with late-acquired cochlear implants versus normal hearing adults.

Training with audiovisual (AV) speech has been shown to promote auditory perceptual learning of vocoded acoustic speech by adults with normal hearing. In Experiment 1, we investigated whether AV speech promotes auditory-only (AO) perceptual learning in prelingually deafened adults with late-acquired cochlear implants. Participants were assigned to learn associations between spoken disyllabic C(=consonant)V(=vowel)CVC non-sense words and non-sense pictures (fribbles), under AV and then AO (AV-AO; or counter-balanced AO then AV, AO-AV, during Periods 1 then 2) training conditions. After training on each list of paired-associates (PA), testing was carried out AO. Across all training, AO PA test scores improved (7.2 percentage points) as did identification of consonants in new untrained CVCVC stimuli (3.5 percentage points). However, there was evidence that AV training impeded immediate AO perceptual learning: During Period-1, training scores across AV and AO conditions were not different, but AO test scores were dramatically lower in the AV-trained participants. During Period-2 AO training, the AV-AO participants obtained significantly higher AO test scores, demonstrating their ability to learn the auditory speech. Across both orders of training, whenever training was AV, AO test scores were significantly lower than training scores. Experiment 2 repeated the procedures with vocoded speech and 43 normal-hearing adults. Following AV training, their AO test scores were as high as or higher than following AO training. Also, their CVCVC identification scores patterned differently than those of the cochlear implant users. In Experiment 1, initial consonants were most accurate, and in Experiment 2, medial consonants were most accurate. We suggest that our results are consistent with a multisensory reverse hierarchy theory, which predicts that, whenever possible, perceivers carry out perceptual tasks immediately based on the experience and biases they bring to the task. We point out that while AV training could be an impediment to immediate unisensory perceptual learning in cochlear implant patients, it was also associated with higher scores during training.

Age Differences in the Effects of Experimenter-Instructed Versus Self-Generated Strategy Use

Background/Study Context: Interactive imagery is superior to rote repetition as an encoding strategy for paired associate (PA) recall. Younger and older individuals often rate these strategies as equally effective before they gain experience using each strategy. The present study investigated how experimenter-supervised and participant-chosen strategy experience affected younger and older adults’ knowledge about the effectiveness of these two strategies. Methods: Ninety-nine younger (M = 19.0 years, SD = 1.4) and 90 older adults (M = 70.4 years, SD = 5.2) participated in the experiment. In learning a first PA list participants were either instructed to use imagery or repetition to study specific items (supervised) or could choose their own strategies (unsupervised). All participants were unsupervised on a second PA list to evaluate whether strategy experience affected strategy knowledge, strategy use, and PA recall. Results: Both instruction groups learned about the superiority of imagery use through task experience, downgrading repetition ratings and upgrading imagery ratings on the second list. However, older adults showed less knowledge updating than did younger adults. Previously supervised younger adults increased their imagery use, improving PA recall; older adults maintained a higher level of repetition use. Conclusion: Older adults update knowledge of the differential effectiveness of the rote and imagery strategies, but to a lesser degree than younger adults. Older adults manifest an inertial tendency to continue using the repetition strategy even though they have learned that it is inferior to interactive imagery.

FC07-04 - Electrophysiological neuroimaging reveals re-set, re-activation and re-processing of procedural and declarative memory traces during post-training sleep

ObjectivesExperience-dependent cortical plasticity observed during post-training sleep has been hypothesized to be part of the global process of memory consolidation. Combining the temporal resolution of microstructure detectors and the spatial resolution of low-resolution brain electromagnetic tomography (LORETA) makes it possible to investigate when and where the experience-dependent reactivation occurs under normal (undisturbed) sleeping conditions.MethodsAfter an adaptation night, in the 2nd and 3rd night 48 young healthy volunteers were randomly assigned either to a control condition or to an experimental condition (declarative memory task: paired-associate word list or procedural memory task: mirror tracing). Sleep stages and sleep microstructures (slow waves, spindles and theta bursts) were detected automatically by means of the Somnolyzer 24x7. Changes in LORETA sources (experimental minus control night) were correlated with changes in memory performance (morning minus evening recall).ResultsOvernight improvements in the mirror tracing task were correlated with increased slow-wave sources in the right posterior parietal cortex (r = .70,p < 0.01) during NREM sleep and with desynchronized (r = −.76,p < 0.01) and synchronized (r = .62,p < 0.01) rolandic mu rhythm sources during periods with theta bursts in REM sleep. Overnight improvements in the declarative memory task were significantly correlated with increased spindle sources (r = .52, p < .01) in frontal, temporal and cingulate brain regions.ConclusionsThe present study supports the hypotheses of (1) a use-dependent reset of synaptic plasticity during slow-wave sleep (restorative function), (2) an experience-dependent reactivation during spindle episodes (stabilizing function) and (3) an off-line neuronal reprocessing during REM sleep (improvement without further training for novel tasks).

Bridging the gap: Transitive associations between items presented in similar temporal contexts.

In episodic memory tasks, associations are formed between items presented close together in time. The temporal context model (TCM) hypothesizes that this contiguity effect is a consequence of shared temporal context rather than temporal proximity per se. Using double-function lists of paired associates (e.g., A-B, B-C) presented in a random order, the authors examined associations between items that were not presented close together in time but that were presented in similar temporal contexts. After learning, across-pair associations fell off with distance in the list, as if subjects had integrated the pairs into a coherent memory structure. Within-pair associations (e.g., A-B) were strongly asymmetric favoring forward transitions; across-pair associations (e.g., A-C) showed no evidence of asymmetry. While this pattern of results presented a stern challenge for a heteroassociative mediated chaining model, TCM provided an excellent fit to the data. These findings suggest that contiguity effects in episodic memory do not reflect direct associations between items but rather a process of binding, encoding, and retrieval of a gradually changing representation of temporal context.

Functional MRI investigation of verbal selection mechanisms in lateral prefrontal cortex

Response selection activates appropriate response representations to task-relevant environmental stimuli. Research implicates dorsolateral prefrontal cortex (dlPFC) for this process. On the other hand, studies of semantic selection, which activates verbal responses based on the semantic requirements of a task, implicate ventrolateral PFC (vlPFC). Despite this apparent dissociation, the neurocognitive distinction between response and semantic selection is controversial. The current functional MRI study attempts to resolve this controversy by investigating verbal response and semantic selection in the same participants. Participants responded vocally with a word to a visually presented noun, either from a memorized list of paired associates (response selection task), or by generating a semantically related verb (semantic selection task). We found a dissociation in left lateral PFC. Activation increased significantly in dlPFC with response selection difficulty, but not semantic selection difficulty. Conversely, semantic, but not response, selection difficulty increased activity significantly in vlPFC. Activity in left parietal cortex, on the other hand, was affected by difficulty increases in both selection tasks. These results suggest that response and semantic selection may be distinct cognitive processes mediated by different regions of lateral PFC; but both of these selection processes rely on cognitive mechanisms mediated by parietal cortex.

How is knowledge generated about memory encoding strategy effectiveness?

This study evaluated how people learn about encoding strategy effectiveness in an associative memory task. Individuals studied two lists of paired associates under instructions to use either a normatively effective strategy (interactive imagery) or a normatively ineffective strategy (rote repetition) for each pair. Questionnaire ratings of imagery effectiveness increased and ratings of repetition effectiveness decreased after task experience, demonstrating new knowledge about strategy effectiveness. Cued recall confidence judgments, measuring confidence in recall accuracy, were almost perfectly correlated with actual recall and strongly correlated with postdictions—estimates of recall for each strategy. A structural regression model revealed that postdictions mediated both changes in second-list predictions and changes in strategy effectiveness ratings, implicating accurate performance estimates based on item-level monitoring as the key to updating strategy knowledge.

Declarative and procedural memory consolidation during sleep in patients with borderline personality disorder

Borderline personality disorder (BPD) is characterized by changes in subjective and objective measures of sleep quality. As recent findings point to the importance of sleep in memory consolidation, sleep-related memory consolidation was investigated in 15 female BPD patients (mean age 26.1 ± 6.1 years) and 15 female healthy controls (mean age 25.6 ± 6.8 years). Before and after the study night, declarative and procedural memory performance was tested by a paired associate list and a mirror tracing task. Subjective sleep quality was assessed by a sleep questionnaire, objective sleep quality was measured by a portable sleep recording device. During the study night the restorative value of sleep was significantly reduced in BPD patients ( p < 0.001), while objective sleep quality showed a trend for longer REM sleep duration ( p = 0.054). No significant differences were found regarding overnight performance improvement in the declarative and procedural memory tasks. Present findings suggest that declarative and procedural memory consolidation during sleep is intact in BPD patients.

Dual-task interference is greater in delayed grasping than in visually guided grasping

Previous kinematic research suggests that visually guided grasping employs an accurate real-time control system in the dorsal stream, whereas delayed grasping relies on less accurate stored information derived by the perceptual system in the ventral stream. We explored these ideas in two experiments combining visually guided and delayed grasping with auditory tasks involving perception-based imagery and semantic memory. In both experiments, participants were cued to grasp three-dimensional objects of varying sizes. During visually guided trials, objects were visible during the interval between the cue and movement onset. During delayed trials, objects were occluded at the time of the cue. In Experiment 1, the second task required participants to listen to object names and vocally respond if the objects were of a particular shape. In Experiment 2, participants studied a paired-associates list prior to testing and then performed cued recall while grasping. The results of these experiments showed that there was reciprocal interference on both tasks, which was consistently greater during delayed grasping. Experiment 2 showed that the introduction of the second task resulted in larger grip apertures during delayed grasping. This supports the idea that delayed grasping involves processing of stored perception-based information that shares resources with cross-modal tasks involving imagery and memory.

Effects of age on contextually mediated associations in paired associate learning.

Older and young adults learned single-function lists of paired associates with no contextual overlap (e.g., J-K, L-M) and double-function lists of paired associates consisting of chains of pairs (e.g., A-B, B-C). Although young adults outperformed older adults on both pair types, there was a robust Pair Type x Age interaction. Evidence from intrusion analyses shows that older adults performed better than would be expected on the contextually overlapping double-function pairs because they were less subject to response competition for the double-function pairs. Young adults made a larger proportion of backward and remote intrusions to double-function probes than did older adults. Thus, group differences in both correct-recall probabilities and intrusion analysis suggest that backward and transitive associations are sensitive to aging. The results are discussed within the theoretical framework of the temporal context model and the hypothesis that older adults are impaired at forming new item-context associations.

The Relationship Between REM Sleep and Memory Consolidation in Old Age and Effects of Cholinergic Medication

Recent findings in young adults suggest that rapid eye movement (REM) sleep plays a role in procedural memory consolidation. The significance of REM sleep for memory consolidation in old age has not yet been investigated. Effects of REM sleep manipulation on declarative and procedural memory consolidation were investigated in 107 healthy older adults, ages 60-82 years. Rapid eye movement sleep deprivation was achieved by REM sleep awakenings and compared with non-REM sleep awakenings. Rapid eye movement sleep augmentation was realized physiologically by REM sleep rebound and pharmacologically by administering an acetylcholinesterase inhibitor in a double-blind, placebo-controlled design. Memory performance was tested by a paired associate list and a mirror tracing task at 9:30 pm and 7:30 am with sleep intervening between 11:00 pm and 7:00 am. Although REM sleep deprivation led to a significant reduction in total and phasic REM sleep, memory consolidation remained unaffected. Both REM sleep augmentation groups showed a significant increase in phasic REM sleep, whereas only pharmacological cholinergic REM sleep manipulation exerted a significant positive effect on procedural memory consolidation. Because only after cholinergic stimulation of phasic REM sleep procedural memory consolidation is improved, cholinergic activation seems to be a crucial component of REM sleep-related memory consolidation in old age.

Measurement of Individual Differences

An examination of test manuals and published research indicates that widely used memory tests (e.g., Verbal Paired Associates and Word List tests of the Wechsler Memory Scale, Rey Auditory Verbal Learning Test, and California Verbal Learning Test) are afflicted by severe ceiling effects. In the present study, the true extent of memory ability in healthy young adults was tested by giving 208 college undergraduates verbal paired-associate and verbal learning tests of various lengths; the findings demonstrate that healthy adults can remember much more than is suggested by the normative data for the memory tests just mentioned. The findings highlight the adverse effects of low ceilings in memory assessment and underscore the severe consequences of ceiling effects on score distributions, means, standard deviations, and all variability-dependent indices, such as reliability, validity, and correlations with other tests. The article discusses the optimal test lengths for verbal paired-associate and verbal list-learning tests, shows how to identify ceiling-afflicted data in published research, and explains how proper attention to this phenomenon can improve future research and clinical practice.

Anchoring effects in the absolute accuracy of immediate versus delayed judgments of learning

This research explored the absolute accuracy of judgments of learning (JOLs), wherein absolute accuracy pertains to how well the magnitude of the participant's predictions of recall correspond to his or her subsequent recall. The Anchoring Hypothesis proposes that the magnitude of JOLs does not change systematically with item difficulty; analogous to a broken clock that is correct twice a day, the absolute magnitude of JOLs may be accurate by chance and not because of any inherent predictive ability. Alternatively, the Monitoring Hypothesis proposes that the magnitude of JOLs does vary systematically with item difficulty. The Dual-Factors hypothesis proposes that the absolute accuracy of JOLs is affected by some combination of monitoring and anchoring. In four experiments, participants studied a list of paired-associates with a high, medium or low normative proportion of recall, then made JOLs for every item, and subsequently had a recall test. The absolute accuracy of JOLs was investigated both for immediate JOLs and for delayed JOLs. The results were consistent with the Monitoring Hypothesis for delayed JOLs and with the Dual-Factors Hypothesis for immediate JOLs.

Comparing objective and subjective learning curves: Judgments of learning exhibit increased underconfidence with practice.

When participants studied a list of paired associates for several study-test cycles, their judgments of learning (JOLs) exhibited relatively good calibration on the 1st cycle, with a slight overconfidence. However, a shift toward marked underconfidence occurred from the 2nd cycle on. This underconfidence-with-practice (UWP) effect was very robust across several experimental manipulations, such as feedback or no feedback regarding the correctness of the answer, self-paced versus fixed-rate presentation, different incentives for correct performance, magnitude and direction of associative relationships, and conditions producing different degrees of knowing. It was also observed both in item-by-item JOLs and in aggregate JOLs. The UWP effect also occurred for list learning and for the memory of action events. Several theoretical explanations for this counterintuitive effect are discussed.

Effects of Cues on Memory in Alcoholics and Controls

This study was conducted to determine whether alcoholics' memory difficulties are due, in part, to access (retrieval) or to availability (retention) deficits. Forty-four alcoholics (n = 20 females) and 44 controls (n = 22 females) learned a paired associate list consisting of 12 adjective-CCC trigram pairs. Half of the subjects in each group learned the list to a low degree of learning (DOL; 4/12 pairs); the remainder to a high DOL (8/12 pairs). Two distinct environmental contexts (providing implicit cues) were used during acquisition. Subjects then completed a cued recall (an explicit cue) test in either the same or a different room. Alcoholics were significantly inferior in the acquisition phase on trials required to reach criterion, regardless of DOL required [F(1,68) = 10.92, p = 0.002]. The main effect for implicit cuing was not significant; similarly, there were no significant interactions. In contrast, the explicit cue manipulation produced a significant group x DOL interaction on the number of trigrams correctly recalled [F = (1,77) = 6.38, p = 0.01]; alcoholics' recall did not benefit from the higher DOL in contrast to a significant improvement in recall by controls. The failure of alcoholics to demonstrate improvement with higher levels of learning is consistent with a deficit in the availability of information. The results confirm previous reports of recovering alcoholics' verbal learning and memory dysfunction, and suggest that these deficits may be attributed, in part, to a deficit in the availability of information (retention).

Effects of triazolam and ethanol on proactive interference: Evidence for an impairment in retrieval inhibition

The effects of two memory-impairing drugs, ethanol and triazolam, on proactive interference (PI) in memory were studied. Following ingestion of either one of these drugs or a placebo, subjects studied an A-B list (e.g., BEE-WASP) of paired associates, followed by an A-C list (e.g., BEE-HONEY) on the interference trial, and a D-E list (e.g., KING-QUEEN) followed by an A-C list on the control trial. A PI effect was found in the data, such that subjects produced fewer correct second list targets on the interference trial than on the control trial. Neither ethanol nor triazolam was found to influence the size of the PI effect. However, both drugs were found to increase B intrusions on the test of the A-C list, to impair subjects' ability to produce more than one studied response for each cue word, and to impair the subjective experience of retrieved memory information. These data suggest that ethanol and triazolam impair an inhibitory process that normally operates as one component of intentional retrieval, playing an important role in the suppression of unwanted information during a memory task.