Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Serial Learning”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 685 records · Page 38Linked to original sources
PubMed2005

Practice effects and the use of alternate forms in serial neuropsychological testing.

Accurate understanding of practice characteristics, performance stability, and error on neuropsychological tests is essential to both valid clinical assessment and maximization of signal detection for clinical trials of cognitive enhancing drugs. We examined practice effects in 28 healthy adults. As part of a larger study using donepezil and simulating a Phase I trial, participants were randomized into: placebo, no-treatment and donepezil. Donepezil results are presented elsewhere. Neuropsychological tests were administered in a fixed order for 6 weeks, with alternate forms available for most tests. Despite alternate forms, ANOVAs revealed significant improvements for the pooled control group (placebo and no-treatment) on all tests except Letter Number Sequencing and Trails B. Learning occurred principally in the first three to four sessions. PASAT and Stroop interference showed the greatest learning. Thus, serial assessment with alternate forms may attenuate retest effects on some tests, but continued learning occurs on novel tests or those in which an advantageous test-taking strategy can be identified. Alternate forms and baseline practice sessions may help control early, rapid improvements in clinical trials.

Adult↗
PubMed2005

The heterogeneity of picture-supported narratives in Alzheimer's disease.

This study describes discourse patterns produced by 46 Alzheimer disease (AD) patients and 53 normal elderly subjects in two picture-supported narratives. Nine measures derived from a cognitive model of discourse processing were obtained and submitted to cluster analysis. Results indicate that discourse patterns elicited from both stimuli were heterogeneous. Further, they fail to clearly differentiate between normal aging and AD in half of the AD patients. Discourse patterns are examined in light of various sources of heterogeneity including severity of cognitive impairment, subject characteristics, and task demands. The usefulness of discourse as a diagnostic and therapeutic tool is discussed.

Aged↗
PubMed2002

Efficiency of temporal order discrimination as an indicator of bradyphrenia in Parkinson's disease: the inspection time loop task.

To investigate the bradyphrenia hypothesis of Parkinson's disease (PD), 32 patients undertook an information-processing task which measured their efficiency of temporal order discrimination. Their performance was compared with 31 non-PD controls matched on age, sex, years of full-time education and pre-morbid IQ. The task was novel and designed to be sensitive to the clinical phenomenon of bradyphrenia (slowing of mental abilities), in the context of temporal order discrimination without confounding from motor ability deficits. The test (the inspection time loop task; ITloop) required judgements as to the temporal sequence of four single letters. The stimulus duration of the letters in each sequence ranged from 100 to 700ms. The PD group had a significantly lower mean score on the ITloop task than did controls (P=0.02). PD patients perform more poorly on temporal order discrimination judgements even when the task makes no motor demands.

Aged↗
PubMed2001

Higher order sequential effects in psychophysical judgments.

We found that the depth of sequential effects depends on the judgment task. An experiment with squares indicated that stimulus-response pairs up to two trials back were included in the judgment process when subjects were required to make category judgments of size, whereas only the immediately preceding event was incorporated when subjects were making magnitude estimations. In the case of category judgment, interactions between the current stimulus and prior stimuli as well as configural effects indicated that events one and two trials back meet an equivalent function in the judgment process and that these events may jointly operate in one trial. These findings can be explained by a class of models that assume that the position of preceding stimuli relative to the current stimulus is decisive in the judgment process. The multiple-standards model is a representative of this class according to which there are two types of standards: (1) the endpoints of the range as long-term standards and (2) traces of preceding stimuli as short-term standards.

Adult↗
PubMed2004

Extinction and retraining of simultaneous and successive flavor conditioning.

In three experiments, rats received pairings of flavor conditioned stimuli with polycose unconditioned stimuli, in either a simultaneous or a sequential relation. Both temporal relations produced excellent conditioned increases in consumption of the flavors. Separate presentation of the flavors resulted in extinction in both cases. However, restoring the pairing of the flavor with polycose resulted in reconditioning only with the sequential, not with the simultaneous, relation.

Animals↗
PubMed1991

The effects of alcohol on learning as a function of drinking habits.

Thirty-six subjects were categorized as light social drinkers (LSD) and 36 as heavy social drinkers (HSD) on the basis of both biological criteria, gamma-glutamyl transferase (GGT) and the mean corpuscular volume (MCV) and by self-reports of drinking habits. This study examined the effects of alcohol (0.7 ml/kg) and of noise (75 dB(A] on learning and performance, in choice RT and in immediate memory tasks. Each subject was tested in two consecutive sessions (the time factor) under one of the following experimental conditions: (a) silence + placebo; (b) silence + alcohol; (c) noise + placebo; and (d) noise + alcohol. On immediate memory, there was a strong effect of time which interacted with 'drinker' category, suggesting that HSD subjects learn less rapidly than LSD. Time interacted also with state (sober or intoxicated), showing that learning might be impaired even by a moderate dose of alcohol. On the reaction time task no main effects were found but the time X drinker category interaction was significant; in session 1 LSD's RT were shorter than those of HSD. It is suggested that regular heavy drinking might affect the learning abilities of those who are not yet labelled as alcoholics.

Adult↗
PubMed2006

Response times seen as decompression times in Boolean concept use.

This paper reports a study of a multi-agent model of working memory (WM) in the context of Boolean concept learning. The model aims to assess the compressibility of information processed in WM. Concept complexity is described as a function of communication resources (i.e., the number of agents and the structure of communication between agents) required in WM to learn a target concept. This model has been successfully applied in measuring learning times for three-dimensional (3D) concepts (Mathy and Bradmetz in Curr Psychol Cognit 22(1):41-82, 2004). In this previous study, learning time was found to be a function of compression time. To assess the effect of decompression time, this paper presents an extended intra-conceptual study of response times for two- and 3D concepts. Response times are measured in recognition phases. The model explains why the time required to compress a sample of examples into a rule is directly linked to the time to decompress this rule when categorizing examples. Three experiments were conducted with 65, 49, and 84 undergraduate students who were given Boolean concept learning tasks in two and three dimensions (also called rule-based classification tasks). The results corroborate the metric of decompression given by the multi-agent model, especially when the model is parameterized following static serial processing of information. Also, this static serial model better fits the patterns of response times than an exemplar-based model.

Adolescent↗
PubMed2006

Effect of short and long exposure duration and dual-tasking on a global-local task.

Past research has demonstrated a global advantage in responses to visually presented hierarchical stimuli such that, on incongruent trials, the global form interferes with responses to the local level [Kimchi, R. (1992). Primacy of wholistic processing and global/local paradigm: A critical review. Psychological Bulletin, 112, 24-38]. In Experiment 1, 32 adults performed alternating blocks of global or local identification of hierarchical letter stimuli in which the global and local letters were congruent, incongruent, or neutral, and were presented at either a short (17 ms) or long (100 ms) exposure duration. A global advantage was demonstrated at both durations. In the local-directed task, interference on incongruent, relative to neutral, trials was observed at both exposure durations, but facilitation on congruent trials, relative to neutral trials, was present only when stimuli were presented at the long exposure duration. In Experiment 2, global or local identification was performed by another group of 24 adults at either a long or short exposure duration, and also under conditions of full attention (FA) or dual-task (DT) conditions with a digit-monitoring task. Under FA, we again found significant interference at both exposure durations, but facilitation only at the long exposure duration. Under DT conditions, the pattern of facilitation and interference at the short duration remained unchanged. At the long duration, however, dual-tasking eliminated interference in the RT but not error data, while facilitation was present in both sets of data. Results are in line with a perceptual account of the global advantage, and suggest that facilitation requires consciously-mediated processes, whereas interference does not.

Adolescent↗
PubMed2001

Cortisol differentially affects memory in young and elderly men.

Nine young and 11 elderly men participated in this placebo-controlled, double-blind, crossover study (0.5 mg/kg cortisol or intravenous placebo). Participants learned a word list before cortisol administration, and delayed recall was then tested. A 2nd word list was learned and recalled after drug administration. In addition, the Paragraph Recall Test and tests measuring working memory (Digit Span), attention (timed cancellation), and response inhibition (Stroop Color and Word Test) were administered at 2 time points after drug administration. Cortisol reduced recall from the word list learned before treatment in both groups but did not influence recall of the list learned after treatment. In contrast, Digit Span performance was decreased by cortisol in young but not elderly participants. The possibility that differential age-associated brain changes might underlie the present results is discussed.

Adult↗
PubMed2006

Memory abilities in children with subtypes of dyscalculia.

This study examines (a) mathematical skills of 2 subgroups of children with developmental dyscalculia (DD)--1 group with DD only and a second group with DD plus reading disorders (RDD)-and (b) analyzes the memory skills of both groups of children. Fifty 11- and 12-year-old children were selected from public schools in Guadalajara, Mexico. Seventeen children had DD only, 13 had RDD, and 20 were normal controls. Testing included 10 calculation and 6 memory subtests taken from the Evaluación Neuropsicológica Infantil (Matute, Rosselli, Ardila, and Ostrosky, in press). Results indicated that children with DD and children with RDD show a similar pattern of mathematical impairment. Both subgroups had significantly lower scores than the control group in working memory tasks. In addition, the RDD group had significantly lower scores than the control group in visual learning and semantic memory. Although the RDD group scored lower than the DD group in most memory tests, this difference did not reach significance. Working memory tests (digits backwards and sentence repetition) appeared to be the best predictors of mathematical test scores and may represent a major cognitive defect in children with specific defects in mathematics.

Aptitude↗
PubMed2003

Phonological and visuo-spatial working memory in individuals with intellectual disability.

Differences in the storage and rehearsal components of the phonological loop and visuo-spatial sketchpad were investigated in individuals with and without intellectual disability matched on memory span. The group with intellectual disability had specific difficulty in the rehearsal component of the phonological loop, as demonstrated by a weak word length effect compared to the group without intellectual disability. Groups did not differ in the storage component of the phonological loop as indexed by the phonological similarity effect. Also, groups did not differ in the storage or maintenance components of the visuo-spatial sketchpad, having comparable visual similarity and visual complexity effects. However, visual complexity task performance suggested that some aspects of visual processing surpass developmental level expectations for individuals with intellectual disability.

Adolescent↗
PubMed1992

Effects of cocaine and alcohol, alone and in combination, on human learning and performance.

The acute effects of cocaine hydrochloride (4 to 96 mg/70 kg) and alcohol (0 to 1.0 g/kg), administered alone and in combination, were assessed in two experiments with human volunteers responding under a multiple schedule of repeated acquisition and performance of response chains. Subjects were intermittent users of cocaine and regular drinkers who were not cocaine or alcohol dependent. Alcohol was mixed with orange juice and ingested in six drinks within 30 min; cocaine was administered intranasally 45 min after completion of drinking. In each component of the multiple schedule, subjects completed response sequences using three keys of a numeric keypad. In the acquisition component, a new sequence was learned each session. In the performance component, the response sequence always remained the same. Results were consistent in both experiments, despite variations in the order in which the drugs were tested alone and in combination. Alcohol administered alone increased overall percentage of errors and decreased rates of responding in the acquisition component, whereas responding in the performance component generally was unaffected. Cocaine administered alone decreased rates of responding but did not affect accuracy of responding in the acquisition component, and enhanced accuracy of responding without affecting rates of responding in the performance component. The combined doses of cocaine and alcohol attenuated the effects observed with alcohol and cocaine alone. These results suggest that, under the conditions investigated in this study, (a) alcohol produces greater behavioral disruption than cocaine or cocaine-alcohol combinations, (b) cocaine and alcohol each attenuate effects of the other, and (c) such attenuation is most pronounced for cocaine attenuating the disruptive effects of alcohol.

Adult↗
PubMed1993

Anarthria impairs subvocal counting.

We studied subvocal counting in two pure anarthric patients. Analysis showed that they performed definitively worse than normal subjects free to articulate subvocally and their scores were in the lower bounds of the performances of subjects suppressing articulation. These results suggest that subvocal counting is impaired after anarthria.

Adult↗
PubMed1976

Blocking of stimuli and the free recall and subjective organization of EMR adolescents.

Number of unrelated stimulus items presented consistently and spatially grouped (1, 3, or 5) was studied in a multitrial free recall experiment with EMR adolescents. This blocking was effective in (a) improving recall from recently presented items, (b) increasing subjective organization, and (c) leading to the formation of stable clusterable output groups. Some evidence suggested that overall recall also increased as a result of the consistent and simultaneous presentation. Discussion of the results emphasized that for a retarded population the relationship between organization and recall may not be strong unless intensive strategy training is employed.

Adolescent↗
PubMed1977

Neurophysiological aspects and learning processes in schizophrenic patients.

Two groups of schizophrenic patients (acute and chronic subjects) were observed in order to study possible differences in neuropsychological performances and their relationship with symptomatology. 16 acute and 16 chronic patients, aged 18 to 35 years were tested with a battery of neuropsychological tests (Word Association Test, Serial Verbal Learning, Weigl's test, Simple Reaction Times, Choice Continuous Reaction Time). Clinical profiles were evaluated by means of MMPI and WAIS (Wechsler Adult Intelligence Scale). Findings concerning cognitive processes show no significant differences between the two groups. Results suggest a correlation between clinical profiles and performances in acute patients, whereas in chronic subjects this correlation seems markedly reduced. Finally, chronicity (i.e. the length of illness) does not seem so be an important factor in determining consistent defects in neuropsychological performances.

Acute Disease↗
PubMed2005

The influence of the response-stimulus interval on implicit and explicit learning of stimulus sequence.

Three experiments investigated the influence of the response-stimulus interval (RSI) on implicit and explicit learning of stimulus sequences. Participants responded to numerals presented in predetermined positions with alternating long and short RSIs. Half of the participants were instructed explicitly to learn the position sequence. In the transfer phase of Experiments 1 and 2, changing RSI patterns reduced the expression of incidental and intentional learning of position sequence. In Experiment 3 the position sequence was transformed, except that sub-sequences demarcated by long RSIs remained unchanged; this greatly reduced the expression of intentional learning, and slightly reduced that of incidental learning. These results indicate that in implicit learning, stimulus sequences are learned under the constraints of RSIs, whereas in explicit learning, learning independent of RSIs, as well as learning constrained by RSIs, occurs.

Adult↗
PubMed1995

Long-term recall of event sequences in infancy.

The first experiment shows that 11-month-olds can encode novel causal events from a brief period of observational learning, and recall much of the information after 24 h. The second experiment, using both a longitudinal and a cross-sectional design, shows recall of the same events after a delay of 3 months. The infants remembered more individual actions than whole sequences, but reproduced many of the events in their entirety (and always in correct order) after the long delay. Although they also reproduced arbitrarily ordered events immediately after being shown them at 11 months, they began to forget them after 24 h and showed essentially no recall for this type of event after 3 months. The experiments not only indicate long-lasting memory for briefly experienced events in infancy, they also suggest that the factors that organize recall at this young age are similar to those found in older children and adults.

Association Learning↗