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 1,441 records · Page 80Linked to original sources
PubMed2002

Objects and events in the attentional blink.

When two visual targets, T1 and T2, are presented in rapid succession, detection or identification of T2 is almost universally degraded by the requirement to attend to T1 (the attentional blink, or AB). One interesting exception occurs when T1 is a brief gap in a continuous letter stream and the task is to discriminate its duration. One hypothesized explanation for this exception is that an AB is triggered only by attention to a patterned object. The results reported here eliminate this hypothesis. Duration judgments produced no AB whether the judged duration concerned a short gap in the letter stream (Experiment 1) or a letter presentedfor slightly longer than others (Experiment 2). When identification of an identical longer letter T1 was required (Experiment 3), rather than a duration judgment, the AB was reestablished Direct perceptual judgments of letter streams with gaps embedded showed that whereas brief gaps result in the percept of a single, briefly hesitating stream, longer gaps result in the percept of two separate streams with a separating pause. Correspondingly, an AB was produced in Experiment 4, when participants were required to judge the duration of longer T1 gaps. We propose that, like spatially separated objects, temporal events are parsed into discrete, hierarchically organized events. An AB is triggered only when a new attended event is defined, either when a long pause creates a new perceived stream (Experiment 4) or when attention shifts from the stream to the letter level (Experiment 3).

Adult↗
PubMed2002

The phonological-similarity effect differentiates between two working memory tasks.

Working memory is a set of interactive cognitive processes that maintain information on-line and available for analysis. Part of the system is specialized for maintaining verbal information, a core component of which is thought to be a phonological store. On the basis of the study of patients with acquired brain lesions, this store has been localized to the supramarginal and angular gyri of the speech-dominant hemisphere, and some functional neuroimaging studies support this localization. However, other imaging studies localize the phonological store in a more dorsal region of the parietal lobe. To reconcile these findings, we examined the phonological-similarity effect in two different tasks. A phonological-similarity effect was observed only in the task that involved sequential presentation and explicit verbal rehearsal. We conclude that at least one possible source of the differences in brain activation between different working memory tasks may be differences in phonological processing.

Adult↗
PubMed2003

Forward and backward recall: different response time patterns, same retrieval order.

How do people retrieve information in forward and backward recall? To address this issue, we examined response times in directional recall as a function of serial position and list length. Participants memorized lists of four to six words and entered responses at the keyboard. Recall direction was postcued. Response times exhibited asymmetry in terms of direction. In forward recall, response times peaked at the first position, leveling off for subsequent positions. Response times were slower in backward recall than in forward recall and exhibited an inverse U-shaped function with an initial slowdown followed by a continuous speedup. These asymmetries have implications for theoretical models of retrieval in serial recall, including temporal-code, rule-based, and network models. The response time pattern suggests that forward recall proceeds in equal steps across positions, whereas backward recall involves repeated covert cycles of forward recall. Thus, retrieval in both directions involves a forward search.

Adolescent↗
PubMed2003

Sit-and-wait strategies in dynamic visual search.

The role of memory in visual search has lately become a controversial issue. Horowitz and Wolfe (1998) observed that performance in a visual search task was little affected by whether the stimuli were static or randomly relocated every 111 ms. Because a memory-based mechanism, such as inhibition of return, would be of no use in the dynamic condition, Horowitz and Wolfe concluded that memory is likewise not involved in the static condition. However, Horowitz and Wolfe could not effectively rule out the possibility that observers adopted a different strategy in the dynamic condition than in the static condition. That is, in the dynamic condition observers may have attended to a subregion of the display and waited for the target to appear there (sit-and-wait strategy). This hypothesis is supported by experimental data showing that performance in their dynamic condition does not differ from performance in another dynamic condition in which observers are forced to adopt a sit-and-wait strategy by being presented with a limited region of the display only.

Adult↗
PubMed1990

The effect of alcohol consumption on recency discrimination ability: an early screening test for alcohol-induced cognitive impairment.

In this short study the relationship between recency discrimination ability and a measure of alcohol intake was examined using a series of regression analyses. Semi-partial correlations were extracted in order to evaluate which variables (level of alcohol consumption, age and IQ) best predicted recency discrimination performance on both verbal and non-verbal tasks. Results showed that while IQ best predicted performance on the verbal task both IQ and alcohol intake were significant predictors on the non-verbal task. The results are discussed in relation to current findings and the continuity hypothesis.

Adult↗
PubMed1992

Increased desire to smoke during acute stress.

Conditions which promote smoking urges, or desire to smoke, are believed to be important in maintaining smoking behaviour, yet little controlled research has examined acute situational factors which increase desire to smoke. In this study, 16 male and 16 female smokers either smoked or sham-smoked with an unlit cigarette after brief abstinence during two sessions, one involving a stressful computer task and the other a non-stress task. Desire to smoke was greater during the stress vs. non-stress task for sham-smokers (p less than 0.01). Furthermore, although smoking desire decreased markedly after smoking in the smoking smokers (p less than 0.001), even this group tended to report greater desire to smoke during stress (p less than 0.10). There were no differences between males and females. These findings indicate that exposure to stressors increases desire to smoke, and suggest that such situations may be influential in maintaining smoking behaviour in smokers not attempting to quit.

Adult↗
PubMed1982

Cognitive processes and perceived language performance of retarded persons.

The relationship between coding processes and ratings of the language performance of institutionalized, moderately retarded adolescents and adults was studied using an information processing model developed by Das, Kirby & Jarman (1975). Simultaneous and successive coding processes were found to relate to relational thought and to contextual grammatical structure (syntax). These results were discussed in terms of the relationship between coding and auditory-visual processing and the development of suitable language training programmes for retarded residents.

Adult↗
PubMed1990

Free recall of lists of word and sign labels by severely handicapped children.

Two experiments are reported which tested short-term recall of lists of four sign or four word labels by severely handicapped children. The findings suggest that the subjects were more efficient at processing words than signs in short-term memory, and that their organization of sign and word lists were affected by the length of time the material had to be held in short-term store. Both of these effects were influenced by whether or not the subjects had to use the stimuli as labels when making a response.

Adolescent↗
PubMed1990

Comprehension of syntactically indicated sequence by Down's syndrome and other mentally retarded adults.

The ability to comprehend syntactically ordered sequence by Down's syndrome adults and adults with mental retardation of no specific aetiology was studied. Both samples exhibited patterns of comprehension that resembled those of children who are not mentally retarded. However, the Down's syndrome individuals had significantly more difficulty when sequence was indicated by syntax with no supporting extralinguistic context. The Down's syndrome adults appeared to be arrested at an earlier stage of development than the other mentally retarded adults.

Adolescent↗
PubMed2004

Verbal short-term memory in Down's syndrome: an articulatory loop deficit?

BACKGROUND: Verbal short-term memory, as measured by digit or word span, is generally impaired in individuals with Down's syndrome (DS) compared to mental age-matched controls. Moving from the working memory model, the present authors investigated the hypothesis that impairment in some of the articulatory loop sub-components is at the base of the deficient maintenance and recall of phonological representations in individuals with DS. METHODS: Two experiments were carried out in a group of adolescents with DS and in typically developing children matched for mental age. In the first experiment, the authors explored the reliance of these subjects on the subvocal rehearsal mechanism during a word-span task and the effects produced by varying the frequency of occurrence of the words on the extension of the word span. In the second experiment, they investigated the functioning of the phonological store component of the articulatory loop in more detail. RESULTS: A reduced verbal span in DS was confirmed. Neither individuals with DS nor controls engaged in spontaneous subvocal rehearsal. Moreover, the data provide little support for defective functioning of the phonological store in DS. CONCLUSIONS: No evidence was found suggesting that a dysfunction of the articulatory loop and lexical-semantic competence significantly contributed to verbal span reduction in subjects with DS. Alternative explanations of defective verbal short-term memory in DS, such as a central executive system impairment, must be considered.

Adolescent↗
PubMed2006

Verbal short-term memory in individuals with congenital articulatory disorders: new empirical data and review of the literature.

BACKGROUND: To investigate the nature of the articulatory rehearsal mechanism of the Articulatory Loop in Baddeley's Working Memory model, it seems particularly important to study individuals who developed a deficit (dysarthria) or total abolition (anarthria) of the ability to articulate language following a cerebral lesion. METHOD: In this study, a forced-choice recognition procedure for word sequences of increasing length was used to evaluate verbal short-term memory in nine individuals with severe congenital motor and verbal disabilities (seven anarthric and two severely dysarthric) and associated intellectual disability (ID) and 30 normal children of comparable mental age. RESULTS: The normal children exhibited classical phonological similarity effects (better performance on acoustically dissimilar than on similar word lists), word length (greater accuracy on two-syllable than on four-syllable word lists) and frequency of occurrence (an advantage of high-frequency over low-frequency words). Instead, all of these effects were lacking in the experimental group. CONCLUSIONS: These data suggest that persons with congenital anarthria/dysarthria and ID present defective maturation at many levels of the Articulatory Loop and reduced contribution of semantic-lexical processing in the temporary retention of phonological sequences. It is likely that in these individuals both communicative deficits and ID play a role in the impaired development of verbal short-term memory abilities.

Adolescent↗
PubMed2006

A multiple case study of verbal short-term memory in velo-cardio-facial syndrome.

BACKGROUND: Velo-cardio-facial syndrome (VCFS, 22q11.2 deletion) is characterized by severely delayed language development. The current study explored the integrity of verbal short-term memory (STM), a cognitive function critically involved in language development, in eight children with VCFS. METHODS: Using a multiple case study design, we presented a series of STM tasks exploring immediate serial recall for word and non-word lists to eight children with VCFS (aged 8-12 years) and to chronological-age-matched control groups. A first task assessed the integrity of phonological coding in verbal STM by comparing recall for phonologically similar and dissimilar words. Subsequently, the interaction between verbal knowledge and STM capacity was investigated by comparing recall for high- and low-imageability words, for high- and low-frequency words, and for words and non-words. A final task assessed short-term serial order recognition for digit sequences. RESULTS: When computing the number of items recalled in the word recall tasks, independently of their serial position, only one child presented consistent difficulties. Short-term recall of non-words was normal in each child. Phonological similarity and verbal knowledge influenced STM performance to a similar extent in children with VCFS and controls. On the other hand, when applying a strict serial recall criterion, difficulties with the word and non-word recall tasks were observed in most children. Half of the patients were also impaired in the serial order recognition task. CONCLUSIONS: Despite mild intellectual disability, it is possible for short-term retention capacities for verbal item information to be at an age-appropriate level in VCFS. However, STM for serial order information could be impaired more specifically.

Child↗
PubMed2005

Increased control demand results in serial processing: evidence from dual-task performance.

Increased demands on cognitive control trigger changes in processing mode. One such modulation involves a shift from parallel to serial processing. This study assessed the role of control demand in determining whether dual-task processing is performed serially or in parallel. We used two critical indices, based on the response-selection bottleneck model, to show that response selection was serial when a task switch was involved, but partly parallel when the simultaneous performance of the tasks did not involve task switching.

Analysis of Variance↗