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 919 records · Page 51Linked to original sources

Glucose and memory: fractionation of enhancement effects?

Recent research findings indicate that glucose administration enhances some aspects of cognitive functioning. To date, those studies which have investigated the effects of glucose on memory in human participants have concentrated on its apparent ability to attenuate memory impairment. Relatively little research has been done in humans investigating the effects of glucose on memory performance in young healthy participants in whom no memory deficits exist. Moreover, the work which has been conducted in this population has produced somewhat equivocal findings. In this study, after overnight fasting the influence of a 25 g oral dosage of glucose on a range of measures of memory performance was investigated in healthy young female participants. Two control treatments (saccharin and water) were also administered. There was a significant glucose facilitation effect upon performance of long-term verbal free and cued recall tasks which did not vary with test delay. Performance on these free and cued verbal recall measures correlated significantly with blood glucose levels across all participants. No glucose-related facilitation was observed on either a test of short-term verbal memory (forwards/backwards digit recall) or a test of long-term non-verbal memory (complex figure reproduction). However, the significant glucose-related effects observed with long-term free and cued recall remained after controlling for participants' differential baseline blood glucose levels and individual levels of immediate memory performance. Therefore, memory improvement after glucose ingestion was not merely a consequence of lower baseline blood glucose or lower immediate memory performance in the glucose treatment group. These findings indicate that there may be some fractionation in the memory facilitation effects of glucose: the memory enhancing effect of glucose administration in healthy young adults may be greatest on tests of long-term verbal recall. The results suggest that glucose may enhance retention in and/or retrieval from long-term verbal memory.

Adolescent↗

The item-order hypothesis reconsidered: the role of order information in free recall.

According to the item-order approach of free recall, in pure short lists the free recall of unrelated items is organized according to their order of presentation in the study list. The approach was applied in the present study to experimenter-performed tasks (EPTs) and subject-performed tasks (SPTs). It claims that EPTs provide better serial order information than SPTs. Consequently, free recall of EPTs should be more organized along the presentation order of the items than the free recall of SPTs. In three experiments, some specific aspects of this approach were studied. Firstly, it was demonstrated that serial retrieval is not strongly used spontaneously and that its use is overestimated in the literature because it is usually evoked by an order reconstruction test which follows free recall testing. Secondly, a serial retrieval strategy in free recall can be encouraged by explicit instructions. Finally, the present experiments showed that a serial output strategy alone does not allow one to predict performance in free recall. The implications of these findings for the item-order approach will be discussed.

Attention↗

Irrelevant auditory attention shifts prime corresponding responses.

In this paper we investigate whether an attention shift towards an auditory signal, while performing a two-choice serial reaction time task, primes responses in the direction of the auditory signal. In Experiment 1, subjects had to react to the pitch of the signal, which was randomly presented to the left or right ear. A short (50-ms) and a long (1000-ms) response-stimulus interval (RSI) was used. In Experiment 2 with an RSI of 2000 ms, subjects had to respond to the color of a centrally presented visual stimulus, while a sound was presented to one of the ears. In the short RSI condition of Experiment 1, there was a Simon effect for location alternations only. In the long RSI condition, there was a Simon effect for location repetitions and alternations. Experiment 2 showed a Simon effect in relation to the accessory sound. The results of this study suggest that an attention shift is a sufficient and necessary condition in order to observe a Simon effect.

Adolescent↗

The influence of string length and repetition on chunking of digit strings.

This study examined the effects of string length and repetitions on number processing with a data entry task. Participants read and entered strings of between three and eight digits and then typed them on the keypad of a computer. Chunking effects were found for all string lengths, with chunk sizes of as small as two digits. Chunk boundary placement varied depending on the length of a digit string, and chunking was avoided at positions between digit repetitions, even when those positions were otherwise common chunk boundaries. Digit repetitions significantly reduced the study time required to process a string prior to its entry. These results are interpreted as showing that flexible chunking strategies and the presence of repetitions are used to facilitate number processing.

Adolescent↗

Serial position effects in implicit memory for multiple-digit numbers.

Serial position effects in implicit and explicit memory were investigated in a short-term memory task. A study list composed of four, spatially distributed, two-digit numbers was presented, followed by an item recognition task (explicit test) and an implicit memory task in which participants were asked to verify a simple addition equation where the presented answer was either primed or not primed by one of the number pairs in the study list. Similar serial position effects were observed in explicit and implicit memory, with faster response times for correct decisions on the first than on the later list positions. The presence of a primacy effect but no recency effect is consistent with previous studies of explicit memory with visual presentation. The results suggest that similar principles of temporal information processing govern priming and episodic short-term memory.

Adolescent↗

Attentional awakening: gradual modulation of temporal attention in rapid serial visual presentation.

Orienting attention to a point in time facilitates processing of an item within rapidly changing surroundings. We used a one-target RSVP task to look for differences in accuracy in reporting a target related to when the target temporally appeared in the sequence. The results show that observers correctly report a target early in the sequence less frequently than later in the sequence. Previous RSVP studies predicted equivalently accurate performances for one target wherever it appeared in the sequence. We named this new phenomenon attentional awakening, which reflects a gradual modulation of temporal attention in a rapid sequence.

Adult↗

Recognition benefits from the reinstatement of a spatial representation of motoric processing.

This study investigated the effect of reinstating the spatial component of motoric processing on recognition memory. In 3 experiments, college students encoded digit strings during a study phase and recognized them during a test phase. During the study phase, participants viewed the digit strings and, in some cases, processed the items motorically by entering them on the numeric keypad of a keyboard. A recognition benefit was found when motoric processing at study was reinstated at test. Additional results showed that recognition could be based on a spatial analogue of the keypressing pattern used to encode the digit strings. These results suggest that the spatial component of a motoric response may serve as a recognition cue for an action. Consistent with the transfer-appropriate processing framework, reinstatement of the entry response or a spatial representation of it improved recognition by increasing the overlap between study and test processing.

Adult↗

List length and the bizarreness effect: support for a hybrid explanation.

The dual-component distinctiveness and expectation-violation explanations of bizarreness effects were compared to a newly proposed hybrid model in a single experiment investigating the influence of list length and list composition on recall for common and unusual verbal information. Although list composition was determined to be an essential variable, the results suggest that list composition does not influence memory directly as a retroactive organizational or retrieval cue. The results do, however, support the notion that list composition influences memory indirectly by altering intralist expectations. Although the results support neither the dual-component nor the expectation-violation explanation as originally formulated, the results are in keeping with the hybrid model which incorporates both intralist and extralist sources of distinctiveness and an expectation-violating mechanism.

Adult↗

Tracking simple and complex sequences.

We address issues of synchronization to rhythms of musical complexity. In two experiments, synchronization to simple and more complex rhythmic sequences was investigated. Experiment 1 examined responses to phase and tempo perturbations within simple, structurally isochronous sequences, presented at different base rates. Experiment 2 investigated responses to similar perturbations embedded within more complex, metrically structured sequences; participants were explicitly instructed to synchronize at different metrical levels (i.e., tap at different rates to the same rhythmic patterns) on different trials. We found evidence that (1) the intrinsic tapping frequency adapts in response to temporal perturbations in both simple (isochronous) and complex (metrically structured) rhythms, (2) people can synchronize with unpredictable, metrically structured rhythms at different metrical levels, with qualitatively different patterns of synchronization seen at higher versus lower levels of metrical structure, and (3) synchronization at each tapping level reflects information from other metrical levels. The latter finding provides evidence for a dynamic and flexible internal representation of the sequence's metrical structure.

Attention↗

Temporal cognition in children with autistic spectrum disorders: tests of diachronic thinking.

Impaired diachronic thinking-(the propensity and capacity to think about events spreading across time)-was demonstrated in a 2-Phase study in which children with autism were compared with age and ability matched controls. Identical tests of diachronic thinking were administered in both phases of the study, but to different participant groups, with the same results. The marked impairments shown are therefore robust. Various non-temporal explanations of the findings were eliminated by the results of control tasks in Phase 2. Diachronic thinking did not correlate with verbal or non-verbal ability, age, or mentalising ability, consistent with other evidence of the specificity of diachronic thinking ability. Possible causes of impaired diachronic thinking in autism are discussed.

Adolescent↗

Auditory event-related potentials, auditory digit span, and clinical symptoms in chronic schizophrenic men on neuroleptic medication.

The aim of this study was to test predictions based on Grossberg's theories of overarousal in neural networks as related to schizophrenic symptomatology. We predicted that symptoms of blunted affect and volition would be associated with reduced P300 amplitude, while impaired attention and short-term memory and symptoms of disorganization would be associated with increased N200 and P300 latency. Event-related potentials, elicited by auditory stimuli, were recorded in 20 chronic schizophrenic men on neuroleptic medication and an age- and sex-matched control group of 20 normal volunteers. The amplitude and latency values of the N200 and P300 waves at the vertex (Cz) were compared with clinical ratings (the Scale for the Assessment of Positive Symptoms and the Scale for the Assessment of Negative Symptoms) and with neuropsychological test scores by means of Spearman rank correlation coefficient. The patients showed a reduced P300 amplitude and an increased N200 latency. No correlation was found between the P300 amplitude and the symptom scores. The N200 latency was negatively correlated with auditory digit span and positively correlated with high global scores for attentional impairment, alogia, and positive formal thought disorder. Our initial predictions are partly confirmed by the apparent association between increased N200 latency and symptoms of disorganization.

Affective Symptoms↗