Data-driven methodology illustrating mechanisms underlying word list recall: Applications to clinical research.

Objective: Word list learning tasks such as the California Verbal Learning Test (CVLT; Delis, Kramer, Kaplan, & Ober, 1987) are widely used to investigate recall strategies. Participants who recall the most words generally employ semantic techniques, whereas those with poor recall (e.g., patients with schizophrenia) rely on serial techniques. However, these conclusions are based on formulas that assume that categories reflect semantic associations, bind strategy to overall performance, and neglect strategy changes over 5 trials. Therefore, we derived novel measures—independent of recall performance—to compute strategies across trials and identify whether diagnosis predicts recall strategy. Method: Participants were included on the basis of performance on the CVLT (i.e., total words recalled over 5 trials). The 50 highest and 50 lowest performers among healthy volunteers (n = 100) and patients with schizophrenia (n = 100) were selected. Novel measures of recall and transition probability were calculated and analyzed by permutation tests. Results: Recall patterns and strategies of patients resembled those of controls with similar performance levels: Regardless of diagnosis, low performers were more likely to recall the first 2 and last 4 items from the list; high performers increased engagement of semantically based transitions across the 5 trials, whereas low performers did not. Conclusions: Cognitive strategy must be considered independent of overall performance before attributing poor performance to degraded learning processes. Our results demonstrate the importance of departing from global scoring techniques, especially when working with clinical populations such as patients with schizophrenia for whom episodic memory deficits are a hallmark feature. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

A stability bias in human memory: Overestimating remembering and underestimating learning.

The dynamics of human memory are complex and often unintuitive, but certain features—such as the fact that studying results in learning—seem like common knowledge. In 12 experiments, however, participants who were told they would be allowed to study a list of word pairs between 1 and 4 times and then take a cued-recall test predicted little or no learning across trials, notwithstanding their large increases in actual learning. When queried directly, the participants espoused the belief that studying results in learning, but they showed little evidence of that belief in the actual task. These findings, when combined with A. Koriat, R. A. Bjork, L. Sheffer, and S. K. Bar’s (2004) research on judgments of forgetting, suggest a stability bias in human memory—that is, a tendency to assume that the accessibility of one’s memories will remain relatively stable over time rather than benefiting from future learning or suffering from future forgetting. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Hypnotic amnesia and temporal organization: Effects of learning set, stimulus type, number of presentations, and hypnotic susceptibility.

Examined the effects of learning set, type of critical material, number of list presentations, and hypnotic susceptibility on the relationship between hypnotic amnesia and seriation in 3 experiments with 268 undergraduates. In Study 1, the critical stimuli were hypnotic test suggestions, and Ss were exposed to either an incidental or intentional learning set. Study 2 again manipulated learning set, but words served as the critical stimuli. Study 3 involved single vs multiple word list presentations prior to amnesia testing. No evidence for an amnesia-specific breakdown in seriation was obtained, and no consistent relationship between hypnotic susceptibility and changes in organization across recall trials emerged. Findings suggest that learning set, stimulus materials, and number of presentations could not account for the discrepant results obtained with the susceptibility scale and word list paradigms. (French abstract) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Effects of age and stimulus structure on serial learning.

Investigated the ability of 4th, 6th, and 8th graders to use structures inherent in a list of permuted symbols. The structures were defined in terms of Piagetian theory, and the sequential stimuli were drawn from previous research. The 240 Ss, 120 males and 120 females equally divided among the 3 grades, were each given 2 lists, 1 random and 1 structured, and were administered 8 serial anticipation trials with each list. The dependent variable was the total number of correct anticipations over the 8 trials. The analysis of variance performed on these data revealed structure to be increasingly facilitative with age, with the less complex structures being more facilitative. Results support the theoretical notion that environmental event structure facilitates learning. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Dissociations of processes in recognition memory: Effects of interference and of response speed.

Examined effects on 2 bases for recognition-memory judgments using a process dissociation procedure and variation in the length of study lists in 3 experiments with 62 undergraduates. Exp 1 defined recollection (RCL) and examined the influence of list length on RCL and familiarity. Exp 2 redefined RCL, and Exp 3 examined differences in the speed of the 2 bases for recognition using a response-signal procedure. It was found that increasing the length of a study list interfered with conscious RCL, but left familiarity in place. An examination of reaction time (RT) distributions, as well as results from a response-signal procedure, showed that familiarity was faster as a basis for recognition judgments than was conscious RCL. Findings indicate that both bases contributed to performance on the fastest as well as the slowest responses, suggesting that the 2 processes were acting in parallel. (French abstract) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Severity of cognitive impairment in Alzheimer's disease affects list learning using the California Verbal Learning Test (CVLT)

Impairment in list learning is considered a primary symptom of Alzheimer's disease (AD), yet there are no published reports examining the relationship between list learning and severity of cognitive impairment. We gave nine-item and 16-item versions of the California Verbal Learning Test (CVLT; Delis et al., 1987), a standardized shopping list assessment of memory, to 24 AD patients (mean age = 76.2 +/- 8.1; mean years of education = 13.8 +/- 2.4), who were stratified into four groups based on MMSE scores (mean = 16.0 +/- 5.6). ANOVAs revealed severity effects for total list learning (p < 0.001), the first trial (p < 0.001), the last trial (p < 0.001) and short- and long-delay recall measures. Most of these differences seemed due to floor effects. For example, the modal number of words recalled after a delay was 0 by subjects with MMSE scores below 21. Severity of cognitive impairment was associated with the proportion of intrusions such that the most severely demented subjects gave almost entirely intrusion responses. Surprisingly, list length did not significantly affect any of the free recall measures. Our results suggest that list learning and recall seem to be lost relatively early in AD. Measures of list recall like the CVLT may not be useful in tracking severity of cognitive impairment over time.     

Differential clinical sensitivity of specific parameters of the Rey Auditory-Verbal Learning Test.

Six 38–77 yr old amnesiacs, 6 25–53 yr old severe head-trauma victims, 6 17–56 yr old schizophrenics, 6 13–30 yr olds with attention deficit disorders, and 6 15–61 yr old psychiatric nonpsychotics were administered a comprehensive clinical neuropsychological evaluation that included the Rey Auditory-Verbal Learning Test (AVLT) and the WAIS. Findings show that the AVLT did not discriminate among groups on the 1st learning trial but did so dramatically after 5 learning trials. A delayed-recall trial following a distractor list showed the most clear-cut discrimination of groups, with results providing a preliminary indication that the amount of loss from the last learning trial to the delayed-recall trial is a sensitive and specific index of primary impairment of learning. Differential results were found on a sequential-organization measure, suggesting that such measures may have clinical utility in evaluating memory disorders. (21 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Review of Developments in the Rorschach technique.

Reviews the book, Developments in the Rorschach technique Vol. 1. Technique and theory by Mary D Ainsworth, Robert R. Holt, Bruno Klopfer, and Walter G. Klopfer (see record 1954-07533-000). There is something for everyone in this first volume of a two-volume work on the Rorschach. Probably the primary use of the book will be as a teaching manual for students learning the mechanics of scoring and the feeling for interpretation, but even experienced users of the technique may read with profit the sections on theory and interpretation. The sections on administration and scoring are written clearly and numerous examples are provided to clarify scoring problems. There is some clarification of methods of scoring shading responses though these distinctions are likely to continue to be frustrating to students. Ten popular responses are listed-the same ones as twelve years ago, and a slightly different list from that offered by other experts. The form-level rating procedure, an attempt to give a numerical score for each percept reflecting its accuracy, will continue to baffle statisticians and others with a bias against adding, subtracting, and averaging cabbages and kings. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Avoidance conditioning of verbal behavior without awareness: A paradigm of repression.

31 male college students responded to a 15-item word association list receiving an electric shock immediately after 5 arbitrarily selected response words. A number of additional trials were given with shock administered every time as S responded with one of the 5 first-trial punished responses. They were then asked to chain-associate to each of the stimulus words with no shock administered. At the conclusion of the experiment Ss could be classified into insight and non-insight groups on the basis of their levels of verbal awareness as to the reasons for the shocks and what they had done to avoid them. Both groups showed a rapid and marked learning of avoidance behavior and a significant decrement in the number of punished responses occurring during chained associations. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Community consultation in socially sensitive research: Lessons from clinical trials of treatments for AIDS.

Contends that few studies have more starkly posed the dilemmas in socially sensitive research than the recent and ongoing clinical trials of medications (such as azidothymidine [AZT]) to treat acquired immune deficiency syndrome (AIDS). One response to such dilemmas is to include potential participants or surrogates for them in decision making. Although the investigator and relevant regulatory bodies are not absolved of responsibility by community consultation, such a procedure may help to create a partnership between the investigator and participants, consistent with ethical duties of respect for persons, beneficence, and fidelity. Community consultation also may dampen participants' anxiety and increase perceived justice of decisions about the research. Such a procedure has the potential to mitigate ethical problems in research involving a wide variety of socially sensitive topics and in randomized clinical trials of treatments for conditions other than AIDS. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Revision of the Brief Visuospatial Memory Test: Studies of normal performance, reliability, and validity.

There is an increasing demand for alternate-form neuropsychological tests that can be used in clinical trials with little risk of direct practice effect. Although the Brief Visuospatial Memory Test ( BVMT ) includes six equivalent alternate forms, its administration is limited to an immediate and 25-min delayed free-recall trial. We now present a revised version of the BVMT called the Brief Visuospatial Memory Test—Revised (BVMT-R) that includes three learning trials, a 25-min delayed recall trial, and a delayed yes/ no recognition task. A new scoring system, which accounts for the location of test stimuli as well as the accuracy of recall, is also introduced. Using these new administration and scoring procedures, we administered the BVMT-R to 261 neuropsychiatric patients and 456 normal healthy adults. The results indicated that the test has excellent interform reliability, and the construct and criterion-related validity of the test were supported in studies using clinical samples. Although the BVMT-R is not without its limitations, the test's brevity and alternate-form capacity make it a valuable instrument for serial neuropsychological assessments. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Is the number of trials a primary determinant of conditioned responding?

Acquisition of conditioned responding is thought to be determined by the number of pairings of a conditioned stimulus (CS) and an unconditioned stimulus (US). However, it is possible that acquisition is primarily determined not by the number of trials but rather by quantities that often correlate with the number of trials, such as cumulative intertrial interval (ITI) and the number of sessions. Four experiments examined whether the number of trials has an effect on acquisition of conditioned responding, once cumulative ITI and number of sessions are equated. Results of the experiments with rats and mice favor the hypothesis that over an eightfold range, variation in number of CS-US pairings has little effect. It is suggested that learning curves might more accurately be plotted across cumulative ITI or number of sessions, and not across number of trials. Results pose a challenge to trial-centered accounts of conditioning, as demonstrated by simulations of the Rescorla-Wagner model, a simplified version of Wagner's standard operating procedure model (SOP), and Stout & Miller's sometimes competing retrieval model (SOCR). A time-centered account, rate estimation theory (RET), predicts the main finding but has trouble with other aspects of the learning process more easily accommodated by trial-centered models. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Effects of meaningfulness on child free-recall learning.

Investigated the effects of experience (age) and stimulus meaningfulness on free-recall learning. In Study 1, meaningfulness values, assessed via the production method, were obtained on 40 trigrams for 120 kindergarten, second- and 6th-grade children. Employing these norms in a subsequent free-recall learning study (Study 2), it was found that trials to criterion and grade level were positively related when meaningfulness was free to vary in the same list stimuli. However, trials-to-criterion differences were equivalent across grade levels when meaningfulness was held constant. Implications for child learning research and theory are discussed. (20 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Serial organization and prior free recall.

Assessed serial recall and organization of a list after different levels of prior free-recall learning with the same list. Performance was expected to be impaired as a direct function of amount of free recall because of inappropriate organizational units formed during free recall. Recall on serial trials following 15 free-recall trials was inferior to 5 or 10 prior free-recall trials. 4 groups of 24 Ss each were tested. Serial organization on the 1st serial trial was inferior if prior free recall occurred, but did not vary with the amount of free recall. These results, and those of part-whole and whole-part free-recall transfer studies, were interpreted by a component analysis of free recall, including response learning/unlearning and organizational learning/unlearning. (16 ref.) (French summary) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Review, recitation, and memory monitoring.

Investigated memory monitoring during the learning of word lists in 110 undergraduates in 2 experiments. Both experiments used a procedure in which the list was presented twice prior to each recall with Ss predicting recall during either the 1st or 2nd presentation. Ss who predicted during the 2nd presentation had the opportunity to review the entire list prior to making their predictions. Results of both experiments suggest that successful monitoring to decide the items that are already encoded (e.g., assessment through covert recall) did not occur during presentation of material but was restricted to recall trials. Reviewing the list had no effect on prediction accuracy when the material was homogeneous (Exp I) but was effective with heterogeneous materials (Exp II). The data from Exp II also show modest learning-to-predict and learning-to-learn effects (i.e., improvement over lists) for Ss predicting recall on the 2nd presentation. (10 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Hormone replacement therapy and other potential treatments for dementias

The past decade has seen a substantial increase in the number of individuals affected by dementia. Dementia places a tremendous personal and economic burden on millions of patients and caregivers annually. Consequently, many scientists have been searching for a treatment for dementia to avoid the imminent public health crisis that will occur if this trend continues. Primary and secondary prevention studies, as well as animal research, demonstrate the potential for hormone replacement therapy (HRT) as an efficacious treatment for dementia. Recently, the Women's Health Initiative-Memory Study began the first randomized, longterm clinical trial to test the hypothesized role of HRT at the onset and in the progression of dementia in women. Researchers also are investigating the potential of other treatments for dementias, such as nonsteroidal anti-inflammatory drugs and free radical scavengers.     

Retention interval hypothesis and list lengths: Comparison of anticipation and study-test procedures.

Notes that a puzzling inconclusiveness has prevailed in the comparison of anticipation and study (reinforcement)-test (RT) procedures in verbal learning. To help to resolve this, the present study elaborated the retention interval hypothesis, applicable to both paired-associate and verbal discrimination learning. Ss were 115 undergraduates. Theoretical and empirical specifications for the effects of the list length (n) factor were supported: n determined the superiority or non-difference for the study-test method compared to the anticipation method. Performance differences between the 2 methods were significant when the list length was intermediate, but were insignificant when it was either too short or too long, where learning was, respectively, either too easy or too difficult. (French summary) (23 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Heterogeneity of protein profiles of Helicobacter pylori isolated from individual patients

A standardized neuropsychological test battery was administered to 167 patients with different forms of mild-to-moderate dementia: probable Alzheimer dementia (AD: n = 49), multi-infarct dementia (n = 43), idiopathic Parkinson disease with dementia (n = 35), depressive pseudodementia (n = 26), and progressive supranuclear palsy (n = 14). Results obtained were used (a) to analyze the profiles of cognitive impairment shown by the different dementia groups; (b) to assess the incidence of some neuropsychological patterns that we hypothesized to be more characteristic of AD, in the various groups; and hence (c) to evaluate the reliability of these patterns as diagnostic markers of AD. Four of the patterns investigated were derived from a verbal learning task (Rey's Auditory Verbal Learning test): (1) absence of the primacy effect; (2) tendency to produce intrusion errors during free recall of a word list; (3) absolute decay of memory trace; and (4) tendency to produce false alarms during delayed recognition of the same word list. Two additional patterns were derived from visual-spatial tasks (copying drawings and Raven's Coloured Progressive Matrices): (5) occurrence of the closing-in phenomenon in copying drawings; and (6) tendency to choose globalistic or odd responses in Raven's matrices. Though all the six patterns were somewhat useful for identifying AD patients, no pattern met the criteria of being both highly sensitive and highly specific, which should characterize an ideal marker. In fact, intrusions and false alarms were observed in many AD patients, but also in patients affected by other forms of dementia. The absence of the primacy effect, the closing-in phenomenon, and the absolute decay of memory trace were more specific, but could be observed in only one-third of AD patients. We also computed the number of positive patterns shown by each patient and assumed the presence of two or more patterns as a global index suggestive of a dementia of the Alzheimer type. With this cumulative method, a higher level of sensitivity and specificity was achieved in the identification of AD patients.     

State-dependent learning in older and younger adults.

In this study state-dependent learning in younger and older adults was compared. State was manipulated by having participants rest or exercise for 5 min, followed by exposure to 3 learning trials of a 20-item word list. After a 20-min delay, participants engaged either in the congruent or in the incongruent activity followed by free-recall trial, cued-recall, and recognition tests. Heart rate, blood pressure, and self-report of distress measures verified that the experimental conditions influenced the participants' physiologic state, but the distracter tasks did not. There was no difference in learning that was due to initial exercise condition, but both age groups showed greater recall when state was congruent before learning and delayed recall. This replicates previous research in which consistent state-dependent learning effects in younger adults were found and supports research suggesting that older adults spontaneously use contextual information to facilitate recall. The demonstration of state-dependent learning in older adults is discussed as an example of implicit memory not affected by aging. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Categorization of natural stimuli by monkeys (Macaca mulatta): Effects of stimulus set size and modification of exemplars.

The concept humans was studied in two experiments on rhesus monkeys, in each of which a two-choice simultaneous discrimination procedure was used. In Experiment 1, the choice was between scenes with humans and scenes without humans, with the slide set sizable enough that a large number of trials could be given without repeating any individual slide. Speed of categorization learning was faster and final level of performance was higher than in prior research in this laboratory involving a much smaller slide set. Experiment 2 was an attempt to obtain some information about the basis for the categorization by means of a series of probe trials. Probe trials involved slides of humans that were modified in one of several ways and slides in which monkeys or apes were present instead of humans. When paired with slides with humans, probe slides were seldom chosen, except when they showed a human rightside up in an upside down scene. In the latter case, choices were at the chance level. When paired with a slide with no humans in the scene, probe slides were usually chosen, except when they showed monkeys or apes or silhouettes of humans, in which case choices were again at the chance level. (PsycINFO Database Record (c) 2010 APA, all rights reserved)