Sample records for operation span task

  1. The Role of Covert Retrieval in Working Memory Span Tasks: Evidence from Delayed Recall Tests

    ERIC Educational Resources Information Center

    McCabe, David P.

    2008-01-01

    The current study examined delayed recall of items that had been processed during simple and complex span tasks. Three experiments were reported showing that despite more items being recalled initially from a simple span task (i.e., word span) than a complex span task (i.e., operation span), on a delayed recall test more items were recalled that…

  2. Proactive and coactive interference in age-related performance in a recognition-based operation span task.

    PubMed

    Zeintl, Melanie; Kliegel, Matthias

    2010-01-01

    Generally, older adults perform worse than younger adults in complex working memory span tasks. So far, it is unclear which processes mainly contribute to age-related differences in working memory span. The aim of the present study was to investigate age effects and the roles of proactive and coactive interference in a recognition-based version of the operation span task. Younger and older adults performed standard versions and distracter versions of the operation span task. At retrieval, participants had to recognize target words in word lists containing targets as well as proactive and/or coactive interference-related lures. Results show that, overall, younger adults outperformed older adults in the recognition of target words. Furthermore, analyses of error types indicate that, while younger adults were only affected by simultaneously presented distracter words, older adults had difficulties with both proactive and coactive interference. Results suggest that age effects in complex span tasks may not be mainly due to retrieval deficits in old age. Copyright 2009 S. Karger AG, Basel.

  3. Temporal-contextual processing in working memory: evidence from delayed cued recall and delayed free recall tests.

    PubMed

    Loaiza, Vanessa M; McCabe, David P

    2012-02-01

    Three experiments are reported that addressed the nature of processing in working memory by investigating patterns of delayed cued recall and free recall of items initially studied during complex and simple span tasks. In Experiment 1, items initially studied during a complex span task (i.e., operation span) were more likely to be recalled after a delay in response to temporal-contextual cues, relative to items from subspan and supraspan list lengths in a simple span task (i.e., word span). In Experiment 2, items initially studied during operation span were more likely to be recalled from neighboring serial positions during delayed free recall than were items studied during word span trials. Experiment 3 demonstrated that the number of attentional refreshing opportunities strongly predicts episodic memory performance, regardless of whether the information is presented in a spaced or massed format in a modified operation span task. The results indicate that the content-context bindings created during complex span trials reflect attentional refreshing opportunities that are used to maintain items in working memory.

  4. The composite complex span: French validation of a short working memory task.

    PubMed

    Gonthier, Corentin; Thomassin, Noémylle; Roulin, Jean-Luc

    2016-03-01

    Most studies in individual differences in the field of working memory research use complex span tasks to measure working memory capacity. Various complex span tasks based on different materials have been developed, and these tasks have proven both reliable and valid; several complex span tasks are often combined to provide a domain-general estimate of working memory capacity with even better psychometric properties. The present work sought to address two issues. Firstly, having participants perform several full-length complex span tasks in succession makes for a long and tedious procedure. Secondly, few complex span tasks have been translated and validated in French. We constructed a French working memory task labeled the Composite Complex Span (CCS). The CCS includes shortened versions of three classic complex span tasks: the reading span, symmetry span, and operation span. We assessed the psychometric properties of the CCS, including test-retest reliability and convergent validity, with Raven's Advanced Progressive Matrices and with an alpha span task; the CCS demonstrated satisfying qualities in a sample of 1,093 participants. This work provides evidence that shorter versions of classic complex span tasks can yield valid working memory estimates. The materials and normative data for the CCS are also included.

  5. The influence of levels of processing on recall from working memory and delayed recall tasks.

    PubMed

    Loaiza, Vanessa M; McCabe, David P; Youngblood, Jessie L; Rose, Nathan S; Myerson, Joel

    2011-09-01

    Recent research in working memory has highlighted the similarities involved in retrieval from complex span tasks and episodic memory tasks, suggesting that these tasks are influenced by similar memory processes. In the present article, the authors manipulated the level of processing engaged when studying to-be-remembered words during a reading span task (Experiment 1) and an operation span task (Experiment 2) in order to assess the role of retrieval from secondary memory during complex span tasks. Immediate recall from both span tasks was greater for items studied under deep processing instructions compared with items studied under shallow processing instructions regardless of trial length. Recall was better for deep than for shallow levels of processing on delayed recall tests as well. These data are consistent with the primary-secondary memory framework, which suggests that to-be-remembered items are displaced from primary memory (i.e., the focus of attention) during the processing phases of complex span tasks and therefore must be retrieved from secondary memory. (c) 2011 APA, all rights reserved.

  6. Functional roles of the cingulo-frontal network in performance on working memory.

    PubMed

    Kondo, Hirohito; Morishita, Masanao; Osaka, Naoyuki; Osaka, Mariko; Fukuyama, Hidenao; Shibasaki, Hiroshi

    2004-01-01

    We examined the relationship between brain activities and task performance on working memory. A large-scale study was initially administered to identify good and poor performers using the operation span and reading span tasks. On the basis of those span scores, we divided 20 consenting participants into high- and low-span groups. In an fMRI study, the participants performed verification of arithmetic problems and retention of target words either concurrently or separately. The behavioral results showed that performance was better in the high-span group than in the low-span group under a dual-task condition, but not under two single-task conditions. The anterior cingulate cortex (ACC), left prefrontal cortex (PFC), left inferior frontal cortex, and bilateral parietal cortex were primarily activated for both span groups. We found that signal changes in the ACC were greater in the high-span group than in the low-span group under the dual-task condition, but not under the single-task conditions. Structural equation modeling indicated that an estimate of effective connectivity from the ACC to the left PFC was positive for the high-span group and negative for the-low span group, suggesting that closer cooperation between the two brain regions was strongly related to working memory performance. We conclude that central executive functioning for attention shifting is modulated by the cingulo-frontal network.

  7. From Brown-Peterson to continual distractor via operation span: A SIMPLE account of complex span.

    PubMed

    Neath, Ian; VanWormer, Lisa A; Bireta, Tamra J; Surprenant, Aimée M

    2014-09-01

    Three memory tasks-Brown-Peterson, complex span, and continual distractor-all alternate presentation of a to-be-remembered item and a distractor activity, but each task is associated with a different memory system, short-term memory, working memory, and long-term memory, respectively. SIMPLE, a relative local distinctiveness model, has previously been fit to data from both the Brown-Peterson and continual distractor tasks; here we use the same version of the model to fit data from a complex span task. Despite the many differences between the tasks, including unpredictable list length, SIMPLE fit the data well. Because SIMPLE posits a single memory system, these results constitute yet another demonstration that performance on tasks originally thought to tap different memory systems can be explained without invoking multiple memory systems.

  8. Stereotype threat as a trigger of mind-wandering in older adults.

    PubMed

    Jordano, Megan L; Touron, Dayna R

    2017-05-01

    Older adults (OAs) report less overall mind-wandering than younger adults (YAs) but more task-related interference (TRI; mind-wandering about the task). The current study examined TRI while manipulating older adults' performance-related concerns. We compared groups for which memory-related stereotype threat (ST) was activated or relieved to a control group. Participants completed an operation span task containing mind-wandering probes. ST-activated OAs reported more TRI than ST-relieved OAs and had worse performance on the operation span task. This study illustrates that environmental context triggers current concerns and determines, in part, the frequency and content of mind-wandering. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  9. Proactive interference and item similarity in working memory.

    PubMed

    Bunting, Michael

    2006-03-01

    Proactive interference (PI) may influence the predictive utility of working memory span tasks. Participants in one experiment (N=70) completed Ravens Advanced Progressive Matrices (RAPM) and multiple versions of operation span and probed recall, modified for the type of memoranda (digits or words). Changing memoranda within- or across-trials released PI, but not doing so permitted PI buildup. Scores from PI-build trials, but not PI-release trials, correlated with RAPM and accounted for as much variance in RAPM as unmodified tasks. These results are consistent with controlled attention and inhibition accounts of working memory, and they elucidate a fundamental component of working memory span tasks.

  10. The Endurance of Children's Working Memory: A Recall Time Analysis

    ERIC Educational Resources Information Center

    Towse, John N.; Hitch, Graham J.; Hamilton, Z.; Pirrie, Sarah

    2008-01-01

    We analyze the timing of recall as a source of information about children's performance in complex working memory tasks. A group of 8-year-olds performed a traditional operation span task in which sequence length increased across trials and an operation period task in which processing requirements were extended across trials of constant sequence…

  11. Comparison of the Working Memory Load in N-Back and Working Memory Span Tasks by Means of EEG Frequency Band Power and P300 Amplitude

    PubMed Central

    Scharinger, Christian; Soutschek, Alexander; Schubert, Torsten; Gerjets, Peter

    2017-01-01

    According to theoretical accounts, both, N-back and complex span tasks mainly require working memory (WM) processing. In contrast, simple span tasks conceptually mainly require WM storage. Thus, conceptually, an N-back task and a complex span task share more commonalities as compared to a simple span task. In the current study, we compared an N-back task, a complex operation span task (Ospan), and a simple digit span task (Dspan) by means of typical WM load-related measures of the Electroencephalogram (EEG) like the parietal alpha and beta frequency band power, the frontal theta frequency band power, and the P300 amplitude, to examine whether these tasks would show commonalities or differences in WM processing-load. We expected that increasing WM-load would generally lead to a decreased alpha and beta frequency band power, an increased theta frequency band power, and a decreased P300 amplitude. Yet, based on the conceptual considerations, we hypothesized that the outcomes of these measures would be more comparable between the N-back and the Ospan as compared to the Dspan. Our hypotheses were partly confirmed. The N-back and the Ospan showed timely more prolonged alpha frequency band power effects as compared to the Dspan. This might indicate higher demands on WM processing in the former two tasks. The theta frequency band power and the P300 amplitude were most pronounced in the N-back task as compared to both span tasks. This might indicate specific demands on cognitive control in the N-back task. Additionally, we observed that behavioral performance measures correlated with changes in EEG alpha power of the N-back and the Ospan, yet not of the Dspan. Taken together, the hypothesized conceptual commonalities between the N-back task and the Ospan (and, for the Dspan, differences) were only partly confirmed by the electrophysiological WM load-related measures, indicating a potential need for reconsidering the theoretical accounts on WM tasks and the value of a closer link to electrophysiological research herein. PMID:28179880

  12. Comparison of the Working Memory Load in N-Back and Working Memory Span Tasks by Means of EEG Frequency Band Power and P300 Amplitude.

    PubMed

    Scharinger, Christian; Soutschek, Alexander; Schubert, Torsten; Gerjets, Peter

    2017-01-01

    According to theoretical accounts, both, N -back and complex span tasks mainly require working memory (WM) processing. In contrast, simple span tasks conceptually mainly require WM storage. Thus, conceptually, an N -back task and a complex span task share more commonalities as compared to a simple span task. In the current study, we compared an N -back task, a complex operation span task (Ospan), and a simple digit span task (Dspan) by means of typical WM load-related measures of the Electroencephalogram (EEG) like the parietal alpha and beta frequency band power, the frontal theta frequency band power, and the P300 amplitude, to examine whether these tasks would show commonalities or differences in WM processing-load. We expected that increasing WM-load would generally lead to a decreased alpha and beta frequency band power, an increased theta frequency band power, and a decreased P300 amplitude. Yet, based on the conceptual considerations, we hypothesized that the outcomes of these measures would be more comparable between the N -back and the Ospan as compared to the Dspan. Our hypotheses were partly confirmed. The N -back and the Ospan showed timely more prolonged alpha frequency band power effects as compared to the Dspan. This might indicate higher demands on WM processing in the former two tasks. The theta frequency band power and the P300 amplitude were most pronounced in the N -back task as compared to both span tasks. This might indicate specific demands on cognitive control in the N -back task. Additionally, we observed that behavioral performance measures correlated with changes in EEG alpha power of the N -back and the Ospan, yet not of the Dspan. Taken together, the hypothesized conceptual commonalities between the N -back task and the Ospan (and, for the Dspan, differences) were only partly confirmed by the electrophysiological WM load-related measures, indicating a potential need for reconsidering the theoretical accounts on WM tasks and the value of a closer link to electrophysiological research herein.

  13. Who multi-tasks and why? Multi-tasking ability, perceived multi-tasking ability, impulsivity, and sensation seeking.

    PubMed

    Sanbonmatsu, David M; Strayer, David L; Medeiros-Ward, Nathan; Watson, Jason M

    2013-01-01

    The present study examined the relationship between personality and individual differences in multi-tasking ability. Participants enrolled at the University of Utah completed measures of multi-tasking activity, perceived multi-tasking ability, impulsivity, and sensation seeking. In addition, they performed the Operation Span in order to assess their executive control and actual multi-tasking ability. The findings indicate that the persons who are most capable of multi-tasking effectively are not the persons who are most likely to engage in multiple tasks simultaneously. To the contrary, multi-tasking activity as measured by the Media Multitasking Inventory and self-reported cell phone usage while driving were negatively correlated with actual multi-tasking ability. Multi-tasking was positively correlated with participants' perceived ability to multi-task ability which was found to be significantly inflated. Participants with a strong approach orientation and a weak avoidance orientation--high levels of impulsivity and sensation seeking--reported greater multi-tasking behavior. Finally, the findings suggest that people often engage in multi-tasking because they are less able to block out distractions and focus on a singular task. Participants with less executive control--low scorers on the Operation Span task and persons high in impulsivity--tended to report higher levels of multi-tasking activity.

  14. Proactive Interference and Item Similarity in Working Memory

    ERIC Educational Resources Information Center

    Bunting, Michael

    2006-01-01

    Proactive interference (PI) may influence the predictive utility of working memory span tasks. Participants in one experiment (N=70) completed Ravens Advanced Progressive Matrices (RAPM) and multiple versions of operation span and probed recall, modified for the type of memoranda (digits or words). Changing memoranda within- or across-trials…

  15. The role of attention during retrieval in working-memory span: a dual-task study.

    PubMed

    Healey, M Karl; Miyake, Akira

    2009-04-01

    We tested the hypothesis that retrieving target words in operation span (OSpan) involves attention-demanding processes. Participants completed the standard OSpan task and a modified version in which all equations preceded all target words. Recall took place under either full attention or easy versus hard divided-attention conditions. Recall suffered under divided attention with the recall decrement being greater for the hard secondary task. Moreover, secondary-task performance was disrupted more by the standard OSpan task than by the modified version with the hard secondary task showing the larger decrement. Finally, the time taken to start recalling the first word was considerably longer for the standard version than for the modified version. These results are consistent with the proposal that successful OSpan task performance in part involves the attention-demanding retrieval of targets from long-term memory.

  16. The stability of working memory: do previous tasks influence complex span?

    PubMed

    Healey, M Karl; Hasher, Lynn; Danilova, Elena

    2011-11-01

    Schmeichel (2007) reported that performing an initial task before completing a working memory span task can lower span scores and suggested that the effect was due to depleted cognitive resources. We showed that the detrimental effect of prior tasks depends on a match between the stimuli used in the span task and the preceding task. A task requiring participants to ignore words reduced performance on a subsequent word-based verbal span task but not on an arrow-based spatial span task. Ignoring arrows had the opposite pattern of effects: reducing performance on the spatial span task but not on the word-based span task. Finally, we showed that antisaccade, a nonverbal task that taxes domain-general processes implicated in working memory, did not influence subsequent performance of either a verbal or a spatial span task. Together these results suggest that while span is sensitive to prior tasks, that sensitivity does not stem from depleted resources. (PsycINFO Database Record (c) 2011 APA, all rights reserved).

  17. Taming a wandering attention: short-form mindfulness training in student cohorts.

    PubMed

    Morrison, Alexandra B; Goolsarran, Merissa; Rogers, Scott L; Jha, Amishi P

    2014-01-06

    Mindfulness training (MT) is a form of mental training in which individuals engage in exercises to cultivate an attentive, present centered, and non-reactive mental mode. The present study examines the putative benefits of MT in University students for whom mind wandering can interfere with learning and academic success. We tested the hypothesis that short-form MT (7 h over 7 weeks) contextualized for the challenges and concerns of University students may reduce mind wandering and improve working memory. Performance on the sustained attention to response task (SART) and two working memory tasks (operation span, delayed-recognition with distracters) was indexed in participants assigned to a waitlist control group or the MT course. Results demonstrated MT-related benefits in SART performance. Relative to the control group, MT participants had higher task accuracy and self-reported being more "on-task" after the 7-week training period. MT did not significantly benefit the operation span task or accuracy on the delayed-recognition task. Together these results suggest that while short-form MT did not bolster working memory task performance, it may help curb mind wandering and should, therefore, be further investigated for its use in academic contexts.

  18. The role of processing difficulty in the predictive utility of working memory span.

    PubMed

    Bunting, Michael

    2006-12-01

    Storage-plus-processing working memory span tasks (e.g., operation span [OSPAN]) are strong predictors of higher order cognition, including general fluid intelligence. This is due, in part, to the difficulty of the processing component. When the processing component prevents only articulatory rehearsal, but not executive attentional control, the predictive utility is attenuated. Participants in one experiment (N = 59) completed Raven's Advanced Progressive Matrices (RAPM) and multiple versions of OSPAN and probed recall (PR). A distractor task (high or low difficulty) was added to PR, and OSPAN's processing component was manipulated for difficulty. OSPAN and PR correlated with RAPM when the processing component took executive attentional control. These results are suggestive of resource sharing between processing and storage.

  19. Evaluation of pliers' grip spans in the maximum gripping task and sub-maximum cutting task.

    PubMed

    Kim, Dae-Min; Kong, Yong-Ku

    2016-12-01

    A total of 25 males participated to investigate the effects of the grip spans of pliers on the total grip force, individual finger forces and muscle activities in the maximum gripping task and wire-cutting tasks. In the maximum gripping task, results showed that the 50-mm grip span had significantly higher total grip strength than the other grip spans. In the cutting task, the 50-mm grip span also showed significantly higher grip strength than the 65-mm and 80-mm grip spans, whereas the muscle activities showed a higher value at 80-mm grip span. The ratios of cutting force to maximum grip strength were also investigated. Ratios of 30.3%, 31.3% and 41.3% were obtained by grip spans of 50-mm, 65-mm, and 80-mm, respectively. Thus, the 50-mm grip span for pliers might be recommended to provide maximum exertion in gripping tasks, as well as lower maximum-cutting force ratios in the cutting tasks.

  20. Effects of Working Memory Capacity in Processing Wh-Extractions: Eye-Movement Evidence from Chinese-English Bilinguals

    ERIC Educational Resources Information Center

    Zhou, Huixia; Rossi, Sonja; Li, Juan; Liu, Huanhuan; Chen, Ran; Chen, Baoguo

    2017-01-01

    By using the eye-tracking method, the present study explores whether working memory capacity assessed via the second language (L2) reading span (L2WMC) as well as the operational span task (OSPAN) affects the processing of subject-extraction and object-extraction in Chinese-English bilinguals. Results showed that L2WMC has no effects on the…

  1. Are age-related differences between young and older adults in an affective working memory test sensitive to the music effects?

    PubMed

    Borella, Erika; Carretti, Barbara; Grassi, Massimo; Nucci, Massimo; Sciore, Roberta

    2014-01-01

    There are evidences showing that music can affect cognitive performance by improving our emotional state. The aim of the current study was to analyze whether age-related differences between young and older adults in a Working Memory (WM) Span test in which the stimuli to be recalled have a different valence (i.e., neutral, positive, or negative words), are sensitive to exposure to music. Because some previous studies showed that emotional words can sustain older adults' performance in WM, we examined whether listening to music could enhance the benefit of emotional material, with respect to neutral words, on WM performance decreasing the age-related difference between younger and older adults. In particular, the effect of two types of music (Mozart vs. Albinoni), which differ in tempo, arousal and mood induction, on age-related differences in an affective version of the Operation WM Span task was analyzed. Results showed no effect of music on the WM test regardless of the emotional content of the music (Mozart vs. Albinoni). However, a valence effect for the words in the WM task was found with a higher number of negative words recalled with respect to positive and neutral ones in both younger and older adults. When individual differences in terms of accuracy in the processing phase of the Operation Span task were considered, only younger low-performing participants were affected by the type music, with the Albinoni condition that lowered their performance with respect to the Mozart condition. Such a result suggests that individual differences in WM performance, at least when young adults are considered, could be affected by the type of music. Altogether, these findings suggest that complex span tasks, such as WM tasks, along with age-related differences are not sensitive to music effects.

  2. [Working memory and executive control: inhibitory processes in updating and random generation tasks].

    PubMed

    Macizo, Pedro; Bajo, Teresa; Soriano, Maria Felipa

    2006-02-01

    Working Memory (WM) span predicts subjects' performance in control executive tasks and, in addition, it has been related to the capacity to inhibit irrelevant information. In this paper we investigate the role of WM span in two executive tasks focusing our attention on inhibitory components of both tasks. High and low span participants recalled targets words rejecting irrelevant items at the same time (Experiment 1) and they generated random numbers (Experiment 2). Results showed a clear relation between WM span and performance in both tasks. In addition, analyses of intrusion errors (Experiment 1) and stereotyped responses (Experiment 2) indicated that high span individuals were able to efficiently use the inhibitory component implied in both tasks. The pattern of data provides support to the relation between WM span and control executive tasks through an inhibitory mechanism.

  3. The influence of aging on attentional refreshing and articulatory rehearsal during working memory on later episodic memory performance.

    PubMed

    Loaiza, Vanessa M; McCabe, David P

    2013-01-01

    We investigated age-related changes in two proposed mechanisms of maintenance in working memory, articulatory rehearsal, and attentional refreshing, by examining the consequences of manipulating the opportunity for each on delayed recall. Both experiments utilized modified operation span tasks to vary the opportunity for articulatory rehearsal (Experiment 1) and attentional refreshing opportunities (Experiment 2). In both experiments, episodic memory was tested for items that had been initially studied during the respective operation span task. Older adults' episodic memory benefited less from opportunities for refreshing than younger adults. In contrast, articulatory rehearsal opportunities did not influence episodic memory for either age group. The results suggest that attentional refreshing, and not articulatory rehearsal, is important during working memory in order to bind more accessible traces at later tests, which appears to be more deficient in older adults than younger adults.

  4. Influence of working memory and executive function on stair ascent and descent in young and older adults.

    PubMed

    Gaillardin, Florence; Baudry, Stéphane

    2018-06-01

    This study assessed the influence of attention division, working memory and executive function on stair ascent and descent in young and older adults. Twenty young (25.5 ± 2.1 yrs) and 20 older adults (68.4 ± 5.4 yrs) ascended and descended a 3-step staircase with no simultaneous cognitive task (single-motor task) or while performing a cognitive task (dual-task condition). The cognitive task involved either 1) recalling a word list of the subject's word-span minus 2 words (SPAN-2) to assess the attention division effect, 2) a word list of subject's word-span (SPAN-O) to assess the working memory effect, or 3) recalling in alphabetical order, a word list of the subject's word-span (SPAN-A) to assess the executive function effect. Word-span corresponds to the longest string of words that can be recalled correctly. The duration of ascent and descent of stairs was used to assess the cognitive-motor interaction. Stair ascent and descent duration did not differ between age groups for the single-motor task, and was similar between single-motor task and SPAN-2 in both groups (p > 0.05). In contrast, stair ascent and descent duration increased with SPAN-O compared with SPAN-2 for both groups (p < 0.01). Stair ascent (p = 0.017) and descent (p = 0.008) were longer in SPAN-A than SPAN-O only in older adults. Healthy aging was not associated with a decrease in the capacity to perform motor-cognitive dual tasks that involved ascending and descending of stairs when the cognitive task only required working memory. However, the decrease in dual-task performance involving executive functioning may reflect a subclinical cognitive decline in healthy older adults. Copyright © 2018 Elsevier Inc. All rights reserved.

  5. Individuals with Low Working Memory Spans Show Greater Interference from Irrelevant Information Because of Poor Source Monitoring, Not Greater Activation

    PubMed Central

    Lilienthal, Lindsey; Rose, Nathan S.; Tamez, Elaine; Myerson, Joel; Hale, Sandra

    2014-01-01

    Although individuals with high and low working memory (WM) span appear to differ in the extent to which irrelevant information interferes with their performance on WM tasks, the locus of this interference is not clear. The present study investigated whether, when performing a WM task, high- and low-span individuals differ in the activation of formerly relevant, but now irrelevant items, and/or in their ability to correctly identify such irrelevant items. This was done in two experiments, both of which used modified complex WM span tasks. In Experiment 1, the span task included an embedded lexical decision task designed to obtain an implicit measure of the activation of both currently and formerly relevant items. In Experiment 2, the span task included an embedded recognition judgment task designed to obtain an explicit measure of both item and source recognition ability. The results of these experiments indicate that low-span individuals do not hold irrelevant information in a more active state in memory than high-span individuals, but rather that low-span individuals are significantly poorer at identifying such information as irrelevant at the time of retrieval. These results suggest that differences in the ability to monitor the source of information, rather than differences in the activation of irrelevant information, are the more important determinant of performance on WM tasks. PMID:25921723

  6. Contribution of strategy use to performance on complex and simple span tasks.

    PubMed

    Bailey, Heather; Dunlosky, John; Kane, Michael J

    2011-04-01

    Simple and complex span tasks are widely thought to measure related but separable memory constructs. Recently, however, research has demonstrated that simple and complex span tasks may tap, in part, the same construct because both similarly predict performance on measures of fluid intelligence (Gf) when the number of items retrieved from secondary memory (SM) is equated (Unsworth & Engle, Journal of Memory and Language 54:68-80 2006). Two studies (n = 105 and n = 152) evaluated whether retrieval from SM is influenced by individual differences in the use of encoding strategies during span tasks. Results demonstrated that, after equating the number of items retrieved from SM, simple and complex span performance similarly predicted Gf performance, but rates of effective strategy use did not mediate the span-Gf relationships. Moreover, at the level of individual differences, effective strategy use was more highly related to complex span performance than to simple span performance. Thus, even though individual differences in effective strategy use influenced span performance on trials that required retrieval from SM, strategic behavior at encoding cannot account for the similarities between simple and complex span tasks.

  7. Spatial short-term memory is impaired in dependent betel quid chewers.

    PubMed

    Chiu, Meng-Chun; Shen, Bin; Li, Shuo-Heng; Ho, Ming-Chou

    2016-08-01

    Betel quid is regarded as a human carcinogen by the World Health Organization. It remains unknown whether chewing betel quid has a chronic effect on healthy betel quid chewers' memory. The present study aims to investigate whether chewing betel quid can affect short-term memory (STM). Three groups of participants (24 dependent chewers, 24 non-dependent chewers, and 24 non-chewers) were invited to carry out the matrix span task, the object span task, and the digit span task. All span tasks' results were adopted to assess spatial STM, visual STM, and verbal STM, respectively. Besides, there are three set sizes (small, medium, and large) in each span task. For the matrix span task, results showed that the dependent chewers had worse performances than the non-dependent chewers and the non-chewers at medium and large set sizes. For the object span task and digit span task, there were no differences in between groups. In each group, recognition performances were worse with the increasing set size and showing successful manipulation of memory load. The current study provided the first evidence that dependent betel quid chewing can selectively impair spatial STM rather than visual STM and verbal STM. Theoretical and practical implications of this result are discussed.

  8. Proactive interference and practice effects in visuospatial working memory span task performance.

    PubMed

    Blalock, Lisa Durrance; McCabe, David P

    2011-01-01

    In the current study the influence of proactive interference (PI) and practice on recall from a visuospatial working memory (WM) task was examined. Participants completed a visuospatial WM span task under either high-PI conditions (a traditional span task) or low-PI conditions (a span task with breaks between trials). Trials of each length (i.e., two to five to-be-remembered items) were equally distributed across three blocks in order to examine practice effects. Recall increased across blocks to a greater extent in the low-PI condition than in the high-PI condition, indicating that reducing PI increased recall from WM. Additionally, in the final block the correlation between fluid intelligence and WM recall was stronger for the high-PI condition than the low-PI condition, indicating that practice reduced the strength of the correlation between span task recall and fluid intelligence, but only in the low-PI condition. These results support current theories that propose that one source of variability in recall from WM span task is the build-up of PI, and that PI build-up is an important contributing factor to the relation between visuospatial WM span task recall and higher-level cognition.

  9. Encoding and choice in the task span paradigm.

    PubMed

    Reiman, Kaitlin M; Weaver, Starla M; Arrington, Catherine M

    2015-03-01

    Cognitive control during sequences of planned behaviors requires both plan-level processes such as generating, maintaining, and monitoring the plan, as well as task-level processes such as selecting, establishing and implementing specific task sets. The task span paradigm (Logan in J Exp Psychol Gen 133:218-236, 2004) combines two common cognitive control paradigms, task switching and working memory span, to investigate the integration of plan-level and task-level processes during control of sequential behavior. The current study expands past task span research to include measures of encoding processes and choice behavior with volitional sequence generation, using the standard task span as well as a novel voluntary task span paradigm. In two experiments, we consider how sequence complexity, defined separately for plan-level and task-level complexity, influences sequence encoding (Experiment 1), sequence choice (Experiment 2), sequence memory, and task performance of planned sequences of action. Results indicate that participants were sensitive to sequence complexity, but that different aspects of behavior are most strongly influenced by different types of complexity. Hierarchical complexity at the plan level best predicts voluntary sequence generation and memory; while switch frequency at the task level best predicts encoding of externally defined sequences and task performance. Furthermore, performance RTs were similar for externally and internally defined plans, whereas memory was improved for internally defined sequences. Finally, participants demonstrated a significant sequence choice bias in the voluntary task span. Consistent with past research on choice behavior, volitional selection of plans was markedly influenced by both the ease of memory and performance.

  10. Age, gesture span, and dissociations among component subsystems of working memory.

    PubMed

    Dolman, R; Roy, E A; Dimeck, P T; Hall, C R

    2000-01-01

    Working memory was examined in old and young adults using a series of span tasks, including the forward versions of the visual-spatial and digit span tasks from the Wechsler Memory Scale-Revised, and comparable hand gesture and visual design span tasks. The observation that the young participants performed significantly better on all the tasks except digit span suggested that aging has an impact on some component subsystems of working memory but not others. Analyses of intercorrelations in span performance supports the dissociation among three component subsystems, one for auditory verbal information (the articulatory loop), one for visual-spatial information (visual-spatial scratch-pad), and one for hand/body postural configuration.

  11. Controlling the spotlight of attention: visual span size and flexibility in schizophrenia.

    PubMed

    Elahipanah, Ava; Christensen, Bruce K; Reingold, Eyal M

    2011-10-01

    The current study investigated the size and flexible control of visual span among patients with schizophrenia during visual search performance. Visual span is the region of the visual field from which one extracts information during a single eye fixation, and a larger visual span size is linked to more efficient search performance. Therefore, a reduced visual span may explain patients' impaired performance on search tasks. The gaze-contingent moving window paradigm was used to estimate the visual span size of patients and healthy participants while they performed two different search tasks. In addition, changes in visual span size were measured as a function of two manipulations of task difficulty: target-distractor similarity and stimulus familiarity. Patients with schizophrenia searched more slowly across both tasks and conditions. Patients also demonstrated smaller visual span sizes on the easier search condition in each task. Moreover, healthy controls' visual span size increased as target discriminability or distractor familiarity increased. This modulation of visual span size, however, was reduced or not observed among patients. The implications of the present findings, with regard to previously reported visual search deficits, and other functional and structural abnormalities associated with schizophrenia, are discussed. Copyright © 2011 Elsevier Ltd. All rights reserved.

  12. Simple and Complex Memory Spans and Their Relation to Fluid Abilities: Evidence from List-Length Effects

    ERIC Educational Resources Information Center

    Unsworth, Nash; Engle, Randall W.

    2006-01-01

    Complex (working memory) span tasks have generally shown larger and more consistent correlations with higher-order cognition than have simple (or short-term memory) span tasks. The relation between verbal complex and simple verbal span tasks to fluid abilities as a function of list-length was examined. The results suggest that the simple…

  13. Measurements of auditory-verbal STM span in aphasia: effects of item, task, and lexical impairment.

    PubMed

    Martin, Nadine; Ayala, Jennifer

    2004-06-01

    In the first part of this study, we investigated effects of item and task type on span performance in a group of aphasic individuals with word processing and STM deficits. Group analyses revealed significant effects of item on span performance with span being greater for digits than for words. We also investigated associations between subjects' lexical-semantic and phonological processing abilities and performance on four measures of verbal span (digit and word span, each varied for type of response, verbal vs. pointing) as well as one measure of nonverbal span. We predicted and found that the patterns of association between verbal span tasks and lexical abilities reflected the integrity of language processes and representations deployed in each paradigm used to assess span. Performance on the pointing span task, which engages both lexical-semantic and phonological processes, correlated with measures of both lexical-semantic and phonological abilities. Performance on repetition span, which engages primarily input and output phonological processes, correlated with measures of phonological abilities but not measures of lexical-semantic abilities. However, when partial correlations were performed for two subject groups based on their relative preservation of lexical-semantic ability (less or more than phonological ability), repetition span correlated with lexical-semantic measures only in the subgroup with relatively impaired lexical-semantics. Additionally, performance on the nonverbal span task correlated with measures of phonological abilities, suggesting either a general cognitive deficit affecting verbal and nonverbal STM or possibly, the use of a verbal strategy to perform this task. Our discussion focuses on the interpretation of span measurements in clinical practice and research, as well as the implications of these data for theories of short-term memory and word processing.

  14. Short-term memory predictions across the lifespan: monitoring span before and after conducting a task.

    PubMed

    Bertrand, Julie Marilyne; Moulin, Chris John Anthony; Souchay, Céline

    2017-05-01

    Our objective was to explore metamemory in short-term memory across the lifespan. Five age groups participated in this study: 3 groups of children (4-13 years old), and younger and older adults. We used a three-phase task: prediction-span-postdiction. For prediction and postdiction phases, participants reported with a Yes/No response if they could recall in order a series of images. For the span task, they had to actually recall such series. From 4 years old, children have some ability to monitor their short-term memory and are able to adjust their prediction after experiencing the task. However, accuracy still improves significantly until adolescence. Although the older adults had a lower span, they were as accurate as young adults in their evaluation, suggesting that metamemory is unimpaired for short-term memory tasks in older adults. •We investigate metamemory for short-term memory tasks across the lifespan. •We find younger children cannot accurately predict their span length. •Older adults are accurate in predicting their span length. •People's metamemory accuracy was related to their short-term memory span.

  15. The hard fall effect: high working memory capacity leads to a higher, but less robust short-term memory performance.

    PubMed

    Thomassin, Noémylle; Gonthier, Corentin; Guerraz, Michel; Roulin, Jean-Luc

    2015-01-01

    Participants with a high working memory span tend to perform better than low spans in a variety of tasks. However, their performance is paradoxically more impaired when they have to perform two tasks at once, a phenomenon that could be labeled the "hard fall effect." The present study tested whether this effect exists in a short-term memory task, and investigated the proposal that the effect is due to high spans using efficient facilitative strategies under simple task conditions. Ninety-eight participants performed a spatial short-term memory task under simple and dual task conditions; stimuli presentation times either allowed for the use of complex facilitative strategies or not. High spans outperformed low spans only under simple task conditions when presentation times allowed for the use of facilitative strategies. These results indicate that the hard fall effect exists on a short-term memory task and may be caused by individual differences in strategy use.

  16. Short term memory and working memory in blind versus sighted children.

    PubMed

    Withagen, Ans; Kappers, Astrid M L; Vervloed, Mathijs P J; Knoors, Harry; Verhoeven, Ludo

    2013-07-01

    There is evidence that blind people may strengthen their memory skills to compensate for absence of vision. However, which aspects of memory are involved is open to debate and a developmental perspective is generally lacking. In the present study, we compared the short term memory (STM) and working memory (WM) of 10-year-old blind children and sighted children. STM was measured using digit span forward, name learning, and word span tasks; WM was measured using listening span and digit span backward tasks. The blind children outperformed their sighted peers on both STM and WM tasks. The enhanced capacity of the blind children on digit span and other STM tasks confirms the results of earlier research; the significantly better performance of the blind children relative to their sighted peers on verbal WM tasks is a new interesting finding. Task characteristics, including the verbal nature of the WM tasks and strategies used to perform these tasks, are discussed. Copyright © 2013 Elsevier Ltd. All rights reserved.

  17. Number Conservation is Related to Children’s Prefrontal Inhibitory Control: An fMRI Study of a Piagetian Task

    PubMed Central

    Simon, Grégory; Rossi, Sandrine; Cassotti, Mathieu; Pineau, Arlette; Houdé, Olivier

    2012-01-01

    Although young children can accurately determine that two rows contain the same number of coins when they are placed in a one-to-one correspondence, children younger than 7 years of age erroneously think that the longer row contains more coins when the coins in one of the rows are spread apart. To demonstrate that prefrontal inhibitory control is necessary to succeed at this task (Piaget’s conservation-of-number task), we studied the relationship between the percentage of BOLD signal changes in the brain areas activated in this developmental task and behavioral performance on a Stroop task and a Backward Digit Span task. The level of activation in the right insula/inferior frontal gyrus was selectively related to inhibitory control efficiency (i.e., the Stroop task), whereas the activation in the left intraparietal sulcus (IPS) was selectively related to the ability to manipulate numerical information in working memory (i.e., the Backward Digit Span task). Taken together, the results indicate that to acquire number conservation, children’s brains must not only activate the reversibility of cognitive operations (supported by the IPS) but also inhibit a misleading length-equal-number strategy (supported by the right insula/inferior frontal gyrus). PMID:22815825

  18. Normal Aging of the Attentional Control Functions That Underlie Working Memory.

    PubMed

    Sylvain-Roy, Stéphanie; Lungu, Ovidiu; Belleville, Sylvie

    2015-09-01

    This study assessed the effect of aging on 3 attentional control functions (ACFs)--shifting, inhibition, and updating--and on their contribution to working memory (WM) tasks. Complex WM tasks (the Brown-Peterson procedure, the reading span, and the alpha span) and tasks used to derive composite measures of the ACFs were administered to 75 younger and 75 older adults. Of the 3 ACFs, only inhibition was impaired in aging after controlling for processing speed. Furthermore, the effect of aging on WM tasks was not pervasive, as older adults showed impaired performance on the Brown-Peterson procedure and the reading span but not on the alpha span. When examining the contribution of ACFs to WM in older adults, updating accounted for performance on the Brown-Peterson and reading span tasks, and inhibition was involved in performance on the alpha span task. In younger adults, it was processing speed that contributed the most to WM. This pattern of results suggests that complex WM tasks reflect different ACFs and that this varies as a function of age. © The Author 2014. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  19. The Effect of Orthographic Neighborhood in the Reading Span Task

    ERIC Educational Resources Information Center

    Robert, Christelle; Postal, Virginie; Mathey, Stéphanie

    2015-01-01

    This study aimed at examining whether and to what extent orthographic neighborhood of words influences performance in a working memory span task. Twenty-five participants performed a reading span task in which final words to be memorized had either no higher frequency orthographic neighbor or at least one. In both neighborhood conditions, each…

  20. Working memory deficits in children with reading difficulties: memory span and dual task coordination.

    PubMed

    Wang, Shinmin; Gathercole, Susan E

    2013-05-01

    The current study investigated the cause of the reported problems in working memory in children with reading difficulties. Verbal and visuospatial simple and complex span tasks, and digit span and reaction times tasks performed singly and in combination, were administered to 46 children with single word reading difficulties and 45 typically developing children matched for age and nonverbal ability. Children with reading difficulties had pervasive deficits in the simple and complex span tasks and had poorer abilities to coordinate two cognitive demanding tasks. These findings indicate that working memory problems in children with reading difficulties may reflect a core deficit in the central executive. Copyright © 2012 Elsevier Inc. All rights reserved.

  1. Working Memory Deficits in Children with Reading Difficulties: Memory Span and Dual Task Coordination

    ERIC Educational Resources Information Center

    Wang, Shinmin; Gathercole, Susan E.

    2013-01-01

    The current study investigated the cause of the reported problems in working memory in children with reading difficulties. Verbal and visuospatial simple and complex span tasks, and digit span and reaction times tasks performed singly and in combination, were administered to 46 children with single word reading difficulties and 45 typically…

  2. Investigating the visual span in comparative search: the effects of task difficulty and divided attention.

    PubMed

    Pomplun, M; Reingold, E M; Shen, J

    2001-09-01

    In three experiments, participants' visual span was measured in a comparative visual search task in which they had to detect a local match or mismatch between two displays presented side by side. Experiment 1 manipulated the difficulty of the comparative visual search task by contrasting a mismatch detection task with a substantially more difficult match detection task. In Experiment 2, participants were tested in a single-task condition involving only the visual task and a dual-task condition in which they concurrently performed an auditory task. Finally, in Experiment 3, participants performed two dual-task conditions, which differed in the difficulty of the concurrent auditory task. Both the comparative search task difficulty (Experiment 1) and the divided attention manipulation (Experiments 2 and 3) produced strong effects on visual span size.

  3. The Reading Span Test and Its Predictive Power for Reading Comprehension Ability

    ERIC Educational Resources Information Center

    Friedman, Naomi P.; Miyake, Akira

    2004-01-01

    This study had two major goals: to test the effect of administration method on the criterion validity of a commonly used working memory span test, the reading span task, and to examine the relationship between processing and storage in this task. With respect to the first goal, although experimenter- and participant-administered reading span tasks…

  4. Examining the locus of age effects on complex span tasks.

    PubMed

    McCabe, Jennifer; Hartman, Marilyn

    2003-09-01

    To investigate the locus of age effects on complex span tasks, the authors evaluated the contributions of working memory functions and processing speed. Age differences were found in measures of storage capacity, language processing speed, and lower level speed. Statistically controlling for each of these in hierarchical regressions substantially reduced, but did not eliminate, the complex span age effect. Accounting for lower level speed and storage, however, removed essentially the entire age effect, suggesting that both functions play important and independent roles. Additional evidence for the role of storage capacity was the absence of complex span age differences with span size calibrated to individual word span performance. Explanations for age differences based on inhibition and concurrent task performamce were not supported.

  5. Supertaskers: Profiles in extraordinary multitasking ability.

    PubMed

    Watson, Jason M; Strayer, David L

    2010-08-01

    Theory suggests that driving should be impaired for any motorist who is concurrently talking on a cell phone. But is everybody impaired by this dual-task combination? We tested 200 participants in a high-fidelity driving simulator in both single- and dual-task conditions. The dual task involved driving while performing a demanding auditory version of the operation span (OSPAN) task. Whereas the vast majority of participants showed significant performance decrements in dual-task conditions (compared with single-task conditions for either driving or OSPAN tasks), 2.5% of the sample showed absolutely no performance decrements with respect to performing single and dual tasks. In single-task conditions, these "supertaskers" scored in the top quartile on all dependent measures associated with driving and OSPAN tasks, and Monte Carlo simulations indicated that the frequency of supertaskers was significantly greater than chance. These individual differences help to sharpen our theoretical understanding of attention and cognitive control in naturalistic settings.

  6. Bridge-in-a-Backpack(TM). Task 1 : investigation of span lengths up to 70 feet.

    DOT National Transportation Integrated Search

    2011-08-01

    The Bridge-in-a-Backpack has previously been demonstrated with short spans. The first : constructed one, Neal Bridge in Pittsfield, Maine had a span of 34 feet. This task includes : research and development that demonstrates the technology can be ...

  7. Individual differences in working memory: introduction to the special section.

    PubMed

    Miyake, A

    2001-06-01

    This special section includes a set of 5 articles that examine the nature of inter- and intraindividual differences in working memory, using working memory span tasks as the main research tools. These span tasks are different from traditional short-term memory spans (e.g., digit or word span) in that they require participants to maintain some target memory items (e.g., words) while simultaneously performing some other tasks (e.g., reading sentences). In this introduction, a brief discussion of these working memory span tasks and their characteristics is provided first. This is followed by an overview of 2 major theoretical issues that are addressed by the subsequent articles--(a) the factors influencing the inter- and intraindividual differences in working memory performance and (b) the domain generality versus domain specificity of working memory--and also of some important issues that must be kept in mind when readers try to evaluate the claims regarding these 2 theoretical issues.

  8. Strategic behavior, workload, and performance in task scheduling

    NASA Technical Reports Server (NTRS)

    Moray, Neville; Dessouky, Mohamed I.; Kijowski, Brian A.; Adapathya, Ravi

    1991-01-01

    Scheduling theory is proposed as a normative model for strategic behavior when operators are confronted by several tasks, all of which should be completed within a fixed time span, and when they are free to choose the order in which the tasks should be done. Three experiments are described to investigate the effect of knowing the correct scheduling rule on the efficiency of performance, subjective workload, and choice of strategy under different conditions of time pressure. The most potent effects are from time pressure. The reasons for the weak effect of knowing the rules are discussed, and implications for strategic behavior, displays, and decision aids are indicated.

  9. Impaired decision-making under risk in individuals with alcohol dependence

    PubMed Central

    Brevers, Damien; Bechara, Antoine; Cleeremans, Axel; Kornreich, Charles; Verbanck, Paul; Noël, Xavier

    2014-01-01

    Background Alcohol dependence is associated with poor decision-making under ambiguity, that is, when decisions are to be made in the absence of known probabilities of reward and loss. However, little is known regarding decisions made by individuals with alcohol dependence in the context of known probabilities (decision under risk). In this study, we investigated the relative contribution of these distinct aspects of decision making to alcohol dependence. Methods Thirty recently detoxified and sober asymptomatic alcohol-dependent individuals, and thirty healthy control participants were tested for decision-making under ambiguity (using the Iowa Gambling Task), and decision-making under-risk (using the Cups Task and Coin Flipping Task). We also tested their capacities for working memory storage (Digit-span Forward), and dual-tasking (Operation-span Task). Results Compared to healthy control participants, alcohol-dependent individuals made disadvantageous decisions on the Iowa Gambling Task, reflecting poor decisions under ambiguity. They also made more risky choices on the Cups and Coin Flipping Tasks reflecting poor decision-making under risk. In addition, alcohol-dependent participants showed some working memory impairments, as measured by the dual tasking, and the degree of this impairment correlated with high-risk decision-making, thus suggesting a relationship between processes sub-serving working memory and risky decisions. Conclusion These results suggest that alcohol dependent individuals are impaired in their ability to decide optimally in multiple facets of uncertainty (i.e., both risk and ambiguity), and that at least some aspects of these deficits are linked to poor working memory processes. PMID:24948198

  10. Age Differences in Memory Span

    ERIC Educational Resources Information Center

    Chi, Michelene T. H.

    1977-01-01

    Three experiments were conducted to determine processes underlying age differences in the level of recall in a memory-span task. Five-year-olds recalled fewer items than adults in memory-span tasks involving both familiar and unfamiliar faces, even though the use of rehearsal and recoding strategies was minimized for adults. (MS)

  11. Individual Differences in the Fan Effect and Working Memory Capacity

    ERIC Educational Resources Information Center

    Bunting, M.F.; Conway, A.R.A.; Heitz, R.P.

    2004-01-01

    In opposition to conceptualizing working memory (WM) in terms of a general capacity, we present four experiments that favor the view that individual differences in WM depend on attentional control. High- and low-WM participants, as assessed by the operation span task, learned unrelated sentences for which the subject and predicate of the sentences…

  12. BEHAVIORAL PHARMACOLOGY OF THE ODOR SPAN TASK: EFFECTS OF FLUNITRAZEPAM, KETAMINE, METHAMPHETAMINE AND METHYLPHENIDATE

    PubMed Central

    Galizio, Mark; April, Brooke; Deal, Melissa; Hawkey, Andrew; Panoz-Brown, Danielle; Prichard, Ashley; Bruce, Katherine

    2018-01-01

    The Odor Span Task is an incrementing non-matching-to-sample procedure that permits the study of behavior under the control of multiple stimuli. Rats are exposed to a series of odor stimuli and selection of new stimuli is reinforced. Successful performance thus requires remembering which stimuli have previously been presented during a given session. This procedure has been frequently used in neurobiological studies as a rodent model of working memory; however, only a few studies have examined the effects of drugs on performance in this task. The present experiments explored the behavioral pharmacology of a modified version of the Odor Span Task by determining the effects of stimulant drugs methylphenidate and methamphetamine, NMDA antagonist ketamine, and positive GABAA modulator flunitrazepam. All four drugs produced dose-dependent impairment of performances on the Odor Span Task, but for methylphenidate and methamphetamine, these occurred only at doses that had similar effects on performance of a simple odor discrimination. Generally, these disruptions were based on omission of responding at the effective doses. The effects of ketamine and flunitrazepam were more selective in some rats. That is, some rats tested under flunitrazepam and ketamine showed decreases in accuracy on the Odor Span Task at doses that did not affect simple discrimination performance. These selective effects indicate disruption of within-session stimulus control. Overall, these findings support the potential of the Odor Span Task as a baseline for the behavioral pharmacological analysis of remembering. PMID:27747877

  13. The Structure of Working Memory Abilities across the Adult Life Span

    PubMed Central

    Hale, Sandra; Rose, Nathan S.; Myerson, Joel; Strube, Michael J; Sommers, Mitchell; Tye-Murray, Nancy; Spehar, Brent

    2010-01-01

    The present study addresses three questions regarding age differences in working memory: (1) whether performance on complex span tasks decreases as a function of age at a faster rate than performance on simple span tasks; (2) whether spatial working memory decreases at a faster rate than verbal working memory; and (3) whether the structure of working memory abilities is different for different age groups. Adults, ages 20–89 (n=388), performed three simple and three complex verbal span tasks and three simple and three complex spatial memory tasks. Performance on the spatial tasks decreased at faster rates as a function of age than performance on the verbal tasks, but within each domain, performance on complex and simple span tasks decreased at the same rates. Confirmatory factor analyses revealed that domain-differentiated models yielded better fits than models involving domain-general constructs, providing further evidence of the need to distinguish verbal and spatial working memory abilities. Regardless of which domain-differentiated model was examined, and despite the faster rates of decrease in the spatial domain, age group comparisons revealed that the factor structure of working memory abilities was highly similar in younger and older adults and showed no evidence of age-related dedifferentiation. PMID:21299306

  14. A Psychometric Measure of Working Memory Capacity for Configured Body Movement

    PubMed Central

    Wu, Ying Choon; Coulson, Seana

    2014-01-01

    Working memory (WM) models have traditionally assumed at least two domain-specific storage systems for verbal and visuo-spatial information. We review data that suggest the existence of an additional slave system devoted to the temporary storage of body movements, and present a novel instrument for its assessment: the movement span task. The movement span task assesses individuals' ability to remember and reproduce meaningless configurations of the body. During the encoding phase of a trial, participants watch short videos of meaningless movements presented in sets varying in size from one to five items. Immediately after encoding, they are prompted to reenact as many items as possible. The movement span task was administered to 90 participants along with standard tests of verbal WM, visuo-spatial WM, and a gesture classification test in which participants judged whether a speaker's gestures were congruent or incongruent with his accompanying speech. Performance on the gesture classification task was not related to standard measures of verbal or visuo-spatial working memory capacity, but was predicted by scores on the movement span task. Results suggest the movement span task can serve as an assessment of individual differences in WM capacity for body-centric information. PMID:24465437

  15. Enhancing reading performance through action video games: the role of visual attention span.

    PubMed

    Antzaka, A; Lallier, M; Meyer, S; Diard, J; Carreiras, M; Valdois, S

    2017-11-06

    Recent studies reported that Action Video Game-AVG training improves not only certain attentional components, but also reading fluency in children with dyslexia. We aimed to investigate the shared attentional components of AVG playing and reading, by studying whether the Visual Attention (VA) span, a component of visual attention that has previously been linked to both reading development and dyslexia, is improved in frequent players of AVGs. Thirty-six French fluent adult readers, matched on chronological age and text reading proficiency, composed two groups: frequent AVG players and non-players. Participants performed behavioural tasks measuring the VA span, and a challenging reading task (reading of briefly presented pseudo-words). AVG players performed better on both tasks and performance on these tasks was correlated. These results further support the transfer of the attentional benefits of playing AVGs to reading, and indicate that the VA span could be a core component mediating this transfer. The correlation between VA span and pseudo-word reading also supports the involvement of VA span even in adult reading. Future studies could combine VA span training with defining features of AVGs, in order to build a new generation of remediation software.

  16. The Hebb repetition effect in simple and complex memory span.

    PubMed

    Oberauer, Klaus; Jones, Timothy; Lewandowsky, Stephan

    2015-08-01

    The Hebb repetition effect refers to the finding that immediate serial recall is improved over trials for memory lists that are surreptitiously repeated across trials, relative to new lists. We show in four experiments that the Hebb repetition effect is also observed with a complex-span task, in which encoding or retrieval of list items alternates with an unrelated processing task. The interruption of encoding or retrieval by the processing task did not reduce the size of the Hebb effect, demonstrating that incidental long-term learning forms integrated representations of lists, excluding the interleaved processing events. Contrary to the assumption that complex-span performance relies more on long-term memory than standard immediate serial recall (simple span), the Hebb effect was not larger in complex-span than in simple-span performance. The Hebb effect in complex span was also not modulated by the opportunity for refreshing list items, questioning a role of refreshing for the acquisition of the long-term memory representations underlying the effect.

  17. The visual attention span deficit in dyslexia is visual and not verbal.

    PubMed

    Lobier, Muriel; Zoubrinetzky, Rachel; Valdois, Sylviane

    2012-06-01

    The visual attention (VA) span deficit hypothesis of dyslexia posits that letter string deficits are a consequence of impaired visual processing. Alternatively, some have interpreted this deficit as resulting from a visual-to-phonology code mapping impairment. This study aims to disambiguate between the two interpretations by investigating performance in a non-verbal character string visual categorization task with verbal and non-verbal stimuli. Results show that VA span ability predicts performance for the non-verbal visual processing task in normal reading children. Furthermore, VA span impaired dyslexic children are also impaired for the categorization task independently of stimuli type. This supports the hypothesis that the underlying impairment responsible for the VA span deficit is visual, not verbal. Copyright © 2011 Elsevier Srl. All rights reserved.

  18. The Effect of Pressure on High- and Low-Working-Memory Students: An Elaboration of the Choking under Pressure Hypothesis

    ERIC Educational Resources Information Center

    Wang, Zuowei; Shah, Priti

    2014-01-01

    Sample: Fifty-three third and fourth graders from China participated in this study. Method: Participants' working memory (WM) was assessed by the Automated Operation Span task. Then, they solved mental addition problems of different types under low- and high-pressure conditions. Performance was analysed as a function of pressure condition, working…

  19. Concrete and formal operational thought processes in young adulthood and old age.

    PubMed

    Clayton, V; Overton, W F

    1976-01-01

    A study was conducted to examine the role of concrete and formal operations in a young and old population. In addition, the present study explored the relation between operational thought and Cattell's concept of fluid and crystallized intelligence, as well as the role of differential living arrangements in maintaining operational thought. Eighty females from three age groups (18-20 years, 60-70 years and 70-80 years of age) were tested on a series of Piagetian tasks and indices of fluid and crystallized intelligence. The findings supported the notion that age-related performance differences occur in the area of formal operational thought prior to the time they occur in concrete operational thought. Except for the young sample, the operational tasks were found to be unrelated to fluid intelligence at the age levels represented in this study. Living independently as opposed to living in an old age home did not appear to be a significant factor in maintaining operational thought. Discussion focused on the necessity of identifying those factors which influence the developmental course of formal operational thought across the life span.

  20. The eye movements of dyslexic children during reading and visual search: impact of the visual attention span.

    PubMed

    Prado, Chloé; Dubois, Matthieu; Valdois, Sylviane

    2007-09-01

    The eye movements of 14 French dyslexic children having a VA span reduction and 14 normal readers were compared in two tasks of visual search and text reading. The dyslexic participants made a higher number of rightward fixations in reading only. They simultaneously processed the same low number of letters in both tasks whereas normal readers processed far more letters in reading. Importantly, the children's VA span abilities related to the number of letters simultaneously processed in reading. The atypical eye movements of some dyslexic readers in reading thus appear to reflect difficulties to increase their VA span according to the task request.

  1. Priming performance-related concerns induces task-related mind-wandering.

    PubMed

    Jordano, Megan L; Touron, Dayna R

    2017-10-01

    Two experiments tested the hypothesis that priming of performance-related concerns would (1) increase the frequency of task-related mind-wandering (i.e., task-related interference; TRI) and (2) decrease task performance. In each experiment, sixty female participants completed an operation span task (OSPAN) containing thought content probes. The task was framed as a math task for those in a condition primed for math-related stereotype threat and as a memory task for those in a control condition. In both studies, women whose performance-related concerns were primed via stereotype threat reported more TRI than women in the control. The second experiment used a more challenging OSPAN task and stereotype primed women also had lower math accuracy than controls. These results support the "control failures×current concerns" framework of mind-wandering, which posits that the degree to which the environmental context triggers personal concerns influences both mind-wandering frequency and content. Copyright © 2017 Elsevier Inc. All rights reserved.

  2. The association of context-specific sitting time and physical activity intensity to working memory capacity and academic achievement in young adults.

    PubMed

    Felez-Nobrega, Mireia; Hillman, Charles H; Cirera, Eva; Puig-Ribera, Anna

    2017-08-01

    To examine combined associations between self-reported context-specific sitting time (ST) and physical activity (PA) with working memory capacity (WMC) and academic achievement in a sample of Spanish adults. Undergraduate students (n = 371; 21 years ± 3 years, 44% female) were recruited from University of Vic-Central University of Catalonia. Participants completed a 54-item survey that assessed socio-demographic variables (e.g. age, gender, academic year), min/week of light (LPA), moderate (MPA) and vigorous (VPA) intensity PA (International Physical Activity Questionnaire), min/day of domain-specific ST (Last 7 days sedentary behavior questionnaire) and academic performance (grade point average). WMC was assessed through a multiple complex span task that included: Operation Span, Symmetry Span and Rotation Span. These tasks interleave a processing task with a short list of to-be-remembered items. General linear models-adjusted by PA, ST and gender-assessed combined associations between ST and PA with WMC and academic achievement. Performing more than 3 h/week of MPA was related to increases in WMC (P < 0.001). However, PA was not associated with academic performance. More than 3 h seated on a weekend day while performing non-screen leisure activities were related to reduced WMC after adjusting for PA (P = 0.012). Similarly, >3 h/weekday spent seated in these sedentary activities or in leisure-forms of screen time were inversely associated with academic performance regardless of PA (P = 0.033; P = 0.048). MPA may benefit working memory; however, specific domains of leisure-time sedentary behavior may have an unfavorable influence on working memory and academic performance regardless of time spent in PA. © The Author 2017. Published by Oxford University Press on behalf of the European Public Health Association. All rights reserved.

  3. The Magic Number 70 (Plus or Minus 20): Variables Determining Performance in the Rodent Odor Span Task

    ERIC Educational Resources Information Center

    April, L. Brooke; Bruce, Katherine; Galizio, Mark

    2013-01-01

    The olfactory span task (OST) uses an incrementing non-matching to sample procedure such that the number of stimuli to remember increases during the session. The number of consecutive correct responses (span length) and percent correct as a function of the memory load have been viewed as defining rodent working memory capacity limitations in…

  4. The effects of incentives on visual-spatial working memory in children with attention-deficit/hyperactivity disorder.

    PubMed

    Shiels, Keri; Hawk, Larry W; Lysczek, Cynthia L; Tannock, Rosemary; Pelham, William E; Spencer, Sarah V; Gangloff, Brian P; Waschbusch, Daniel A

    2008-08-01

    Working memory is one of several putative core neurocognitive processes in attention-deficit/hyperactivity disorder (ADHD). The present work seeks to determine whether visual-spatial working memory is sensitive to motivational incentives, a laboratory analogue of behavioral treatment. Participants were 21 children (ages 7-10) with a diagnosis of ADHD-combined type. Participants completed a computerized spatial span task designed to assess storage of visual-spatial information (forward span) and manipulation of the stored information (backward span). The spatial span task was completed twice on the same day, once with a performance-based incentive (trial-wise feedback and points redeemable for prizes) and once without incentives. Participants performed significantly better on the backward span when rewarded for correct responses, compared to the no incentive condition. However, incentives had no effect on performance during the forward span. These findings may suggest the use of motivational incentives improved manipulation, but not storage, of visual-spatial information among children with ADHD. Possible explanations for the differential incentive effects are discussed, including the possibility that incentives prevented a vigilance decrement as task difficulty and time on task increased.

  5. The neural correlates of auditory and visuospatial span in logopenic progressive aphasia and Alzheimer's disease.

    PubMed

    Foxe, David; Leyton, Cristian E; Hodges, John R; Burrell, James R; Irish, Muireann; Piguet, Olivier

    2016-10-01

    Logopenic progressive aphasia (lv-PPA) is a form of primary progressive aphasia and is predominantly associated with Alzheimer's disease (AD) pathology. The neuropsychological profiles of lv-PPA and typical clinical AD are, however, distinct. In particular, these two syndromes differ on attention span measures, where auditory attention span is more impaired in lv-PPA than in AD and visuospatial span appears more impaired in AD than in lv-PPA. The neural basis of these span profiles, however, remains unclear. Sixteen lv-PPA and 21 AD matched patients, and 15 education-matched healthy controls were recruited. All participants were assessed by a neurologist and completed a neuropsychological assessment that included the Wechsler Memory Scale-III Digit and Spatial Span tasks, and underwent a high-resolution structural brain MRI to conduct cortical thickness analyses. Patient groups were impaired on all span tasks compared to Controls. In addition, performance on Digit Span Forward (DSF) was significantly lower in the lv-PPA than the AD group, while Spatial Span Forward (SSF) was significantly lower in the AD than the lv-PPA group. No differences were found between patient groups on the Digit or Spatial Span Backward tasks. Neuroimaging analyses revealed that reduced DSF performance correlated to thinning of the left superior temporal gyrus in the lv-PPA group, whereas reduced SSF performance was related to bilateral precentral sulcus and parieto-occipital thinning in the AD group. Analyses of the backward span tasks revealed that reduced Spatial Span Backward (SSB) performance in the lv-PPA group related to cortical thinning of the left superior parietal lobule. This study demonstrates that while lv-PPA and AD commonly share the same underlying neuropathology, their span profiles are distinct and are mediated by divergent patterns of cortical degeneration. Copyright © 2016 Elsevier Ltd. All rights reserved.

  6. Recognition memory span in autopsy-confirmed Dementia with Lewy Bodies and Alzheimer's Disease.

    PubMed

    Salmon, David P; Heindel, William C; Hamilton, Joanne M; Vincent Filoteo, J; Cidambi, Varun; Hansen, Lawrence A; Masliah, Eliezer; Galasko, Douglas

    2015-08-01

    Evidence from patients with amnesia suggests that recognition memory span tasks engage both long-term memory (i.e., secondary memory) processes mediated by the diencephalic-medial temporal lobe memory system and working memory processes mediated by fronto-striatal systems. Thus, the recognition memory span task may be particularly effective for detecting memory deficits in disorders that disrupt both memory systems. The presence of unique pathology in fronto-striatal circuits in Dementia with Lewy Bodies (DLB) compared to AD suggests that performance on the recognition memory span task might be differentially affected in the two disorders even though they have quantitatively similar deficits in secondary memory. In the present study, patients with autopsy-confirmed DLB or AD, and Normal Control (NC) participants, were tested on separate recognition memory span tasks that required them to retain increasing amounts of verbal, spatial, or visual object (i.e., faces) information across trials. Results showed that recognition memory spans for verbal and spatial stimuli, but not face stimuli, were lower in patients with DLB than in those with AD, and more impaired relative to NC performance. This was despite similar deficits in the two patient groups on independent measures of secondary memory such as the total number of words recalled from long-term storage on the Buschke Selective Reminding Test. The disproportionate vulnerability of recognition memory span task performance in DLB compared to AD may be due to greater fronto-striatal involvement in DLB and a corresponding decrement in cooperative interaction between working memory and secondary memory processes. Assessment of recognition memory span may contribute to the ability to distinguish between DLB and AD relatively early in the course of disease. Copyright © 2015 Elsevier Ltd. All rights reserved.

  7. Recognition Memory Span in Autopsy-Confirmed Dementia with Lewy Bodies and Alzheimer’s Disease

    PubMed Central

    Salmon, David P.; Heindel, William C.; Hamilton, Joanne M.; Filoteo, J. Vincent; Cidambi, Varun; Hansen, Lawrence A.; Masliah, Eliezer; Galasko, Douglas

    2016-01-01

    Evidence from patients with amnesia suggests that recognition memory span tasks engage both long-term memory (i.e., secondary memory) processes mediated by the diencephalic-medial temporal lobe memory system and working memory processes mediated by fronto-striatal systems. Thus, the recognition memory span task may be particularly effective for detecting memory deficits in disorders that disrupt both memory systems. The presence of unique pathology in fronto-striatal circuits in Dementia with Lewy Bodies (DLB) compared to AD suggests that performance on the recognition memory span task might be differentially affected in the two disorders even though they have quantitatively similar deficits in secondary memory. In the present study, patients with autopsy-confirmed DLB or AD, and normal control (NC) participants, were tested on separate recognition memory span tasks that required them to retain increasing amounts of verbal, spatial, or visual object (i.e., faces) information across trials. Results showed that recognition memory spans for verbal and spatial stimuli, but not face stimuli, were lower in patients with DLB than in those with AD, and more impaired relative to NC performance. This was despite similar deficits in the two patient groups on independent measures of secondary memory such as the total number of words recalled from Long-Term Storage on the Buschke Selective Reminding Test. The disproportionate vulnerability of recognition memory span task performance in DLB compared to AD may be due to greater fronto-striatal involvement in DLB and a corresponding decrement in cooperative interaction between working memory and secondary memory processes. Assessment of recognition memory span may contribute to the ability to distinguish between DLB and AD relatively early in the course of disease. PMID:26184443

  8. Maternal immune activation during pregnancy in rats impairs working memory capacity of the offspring.

    PubMed

    Murray, Brendan G; Davies, Don A; Molder, Joel J; Howland, John G

    2017-05-01

    Maternal immune activation during pregnancy is an environmental risk factor for psychiatric illnesses such as schizophrenia in the offspring. Patients with schizophrenia display an array of cognitive symptoms, including impaired working memory capacity. Rodent models have been developed to understand the relationship between maternal immune activation and the cognitive symptoms of schizophrenia. The present experiment was designed to test whether maternal immune activation with the viral mimetic polyinosinic:polycytidylic acid (polyI:C) during pregnancy affects working memory capacity of the offspring. Pregnant Long Evans rats were treated with either saline or polyI:C (4mg/kg; i.v.) on gestational day 15. Male offspring of the litters (2-3months of age) were subsequently trained on a nonmatching-to-sample task with odors. After a criterion was met, the rats were tested on the odor span task, which requires rats to remember an increasing span of different odors to receive food reward. Rats were tested using delays of approximately 40s during the acquisition of the task. Importantly, polyI:C- and saline-treated offspring did not differ in performance of the nonmatching-to-sample task suggesting that both groups could perform a relatively simple working memory task. In contrast, polyI:C-treated offspring had reduced span capacity in the middle and late phases of odor span task acquisition. After task acquisition, the rats were tested using the 40s delay and a 10min delay. Both groups showed a delay-dependent decrease in span, although the polyI:C-treated offspring had significantly lower spans regardless of delay. Our results support the validity of the maternal immune activation model for studying the cognitive symptoms of neurodevelopmental disorders such as schizophrenia. Copyright © 2017 Elsevier Inc. All rights reserved.

  9. Complex Span versus Updating Tasks of Working Memory: The Gap Is Not that Deep

    ERIC Educational Resources Information Center

    Schmiedek, Florian; Hildebrandt, Andrea; Lovden, Martin; Wilhelm, Oliver; Lindenberger, Ulman

    2009-01-01

    How to best measure working memory capacity is an issue of ongoing debate. Besides established complex span tasks, which combine short-term memory demands with generally unrelated secondary tasks, there exists a set of paradigms characterized by continuous and simultaneous updating of several items in working memory, such as the n-back, memory…

  10. Inactivation of Medial Prefrontal Cortex or Acute Stress Impairs Odor Span in Rats

    ERIC Educational Resources Information Center

    Davies, Don A.; Molder, Joel J.; Greba, Quentin; Howland, John G.

    2013-01-01

    The capacity of working memory is limited and is altered in brain disorders including schizophrenia. In rodent working memory tasks, capacity is typically not measured (at least not explicitly). One task that does measure working memory capacity is the odor span task (OST) developed by Dudchenko and colleagues. In separate experiments, the effects…

  11. How age affects memory task performance in clinically normal hearing persons.

    PubMed

    Vercammen, Charlotte; Goossens, Tine; Wouters, Jan; van Wieringen, Astrid

    2017-05-01

    The main objective of this study is to investigate memory task performance in different age groups, irrespective of hearing status. Data are collected on a short-term memory task (WAIS-III Digit Span forward) and two working memory tasks (WAIS-III Digit Span backward and the Reading Span Test). The tasks are administered to young (20-30 years, n = 56), middle-aged (50-60 years, n = 47), and older participants (70-80 years, n = 16) with normal hearing thresholds. All participants have passed a cognitive screening task (Montreal Cognitive Assessment (MoCA)). Young participants perform significantly better than middle-aged participants, while middle-aged and older participants perform similarly on the three memory tasks. Our data show that older clinically normal hearing persons perform equally well on the memory tasks as middle-aged persons. However, even under optimal conditions of preserved sensory processing, changes in memory performance occur. Based on our data, these changes set in before middle age.

  12. Discrepancy of performance among working memory-related tasks in autism spectrum disorders was caused by task characteristics, apart from working memory, which could interfere with task execution.

    PubMed

    Nakahachi, Takayuki; Iwase, Masao; Takahashi, Hidetoshi; Honaga, Eiko; Sekiyama, Ryuji; Ukai, Satoshi; Ishii, Ryouhei; Ishigami, Wataru; Kajimoto, Osami; Yamashita, Ko; Hashimoto, Ryota; Tanii, Hisashi; Shimizu, Akira; Takeda, Masatoshi

    2006-06-01

    Working memory performance has been inconsistently reported in autism spectrum disorders (ASD). Several studies in ASD have found normal performance in digit span and poor performance in digit symbol task although these are closely related with working memory. It is assumed that poor performance in digit symbol could be explained by confirmatory behavior, which is induced due to the vague memory representation of number-symbol association. Therefore it was hypothesized that the performance of working memory task, in which vagueness did not cause confirmatory behavior, would be normal in ASD. For this purpose, the Advanced Trail Making Test (ATMT) was used. The performance of digit span, digit symbol and ATMT was compared between ASD and normal control. The digit span, digit symbol and ATMT was given to 16 ASD subjects and 28 IQ-, age- and sex-matched control subjects. The scores of these tasks were compared. A significantly lower score for ASD was found only in digit symbol compared with control subjects. There were no significant difference in digit span and working memory estimated by ATMT. Discrepancy of scores among working memory-related tasks was demonstrated in ASD. Poor digit symbol performance, normal digit span and normal working memory in ATMT implied that ASD subjects would be intact in working memory itself, and that superficial working memory dysfunction might be observed due to confirmatory behavior in digit symbol. Therefore, to evaluate working memory in ASD, tasks that could stimulate psychopathology specific to ASD should be avoided.

  13. Similarities and Differences between Working Memory and Long-Term Memory: Evidence from the Levels-of-Processing Span Task

    ERIC Educational Resources Information Center

    Rose, Nathan S.; Myerson, Joel; Roediger, Henry L., III; Hale, Sandra

    2010-01-01

    Two experiments compared the effects of depth of processing on working memory (WM) and long-term memory (LTM) using a levels-of-processing (LOP) span task, a newly developed WM span procedure that involves processing to-be-remembered words based on their visual, phonological, or semantic characteristics. Depth of processing had minimal effect on…

  14. Developmental change in proactive interference across the life span: evidence from two working memory tasks.

    PubMed

    Loosli, Sandra V; Rahm, Benjamin; Unterrainer, Josef M; Weiller, Cornelius; Kaller, Christoph P

    2014-04-01

    Working memory (WM) as the ability to temporarily maintain and manipulate various kinds of information is known to be affected by proactive interference (PI) from previously relevant contents, but studies on developmental changes in the susceptibility to PI are scarce. In the present study, we investigated life span development of item-specific PI. To this end, 92 individuals between the ages of 8 and 74 years completed a recent-probes task and an n-back task that both composed experimental manipulations of PI. Regarding global WM development, young adults had higher WM performance than children and older adults in both tasks. Significant PI × Age interactions revealed that susceptibility to PI changed over the life span in both tasks, whereas the developmental course of PI differed between the tasks: Children committed more PI-related errors than young adults in the recent-probes task but showed marginally less PI in the n-back task. Regarding reaction time costs, children did not differ from adults in the recent-probes task and were less affected than adults in the n-back. Older adults showed more PI-related errors than young adults in both tasks. Therefore, as expected, item-specific PI changed over the life span with the young adults being less susceptible to PI than children and older adults. The diverging developmental effects of PI across both tasks, especially in the children, are supposed to reflect different causes for the difficulties regarding resisting PI in children and older adults. These might concern differently developed underlying cognitive processes such as inhibition or recollection, or different responses to task demands across both tasks. PsycINFO Database Record (c) 2014 APA, all rights reserved.

  15. N-back versus Complex Span Working Memory Training.

    PubMed

    Blacker, Kara J; Negoita, Serban; Ewen, Joshua B; Courtney, Susan M

    2017-12-01

    Working memory (WM) is the ability to maintain and manipulate task-relevant information in the absence of sensory input. While its improvement through training is of great interest, the degree to which WM training transfers to untrained WM tasks (near transfer) and other untrained cognitive skills (far transfer) remains debated and the mechanism(s) underlying transfer are unclear. Here we hypothesized that a critical feature of dual n-back training is its reliance on maintaining relational information in WM. In Experiment 1, using an individual differences approach, we found evidence that performance on an n-back task was predicted by performance on a measure of relational WM (i.e., WM for vertical spatial relationships independent of absolute spatial locations); whereas the same was not true for a complex span WM task. In Experiment 2, we tested the idea that reliance on relational WM is critical to produce transfer from n-back but not complex span task training. Participants completed adaptive training on either a dual n-back task, a symmetry span task, or on a non-WM active control task. We found evidence of near transfer for the dual n-back group; however, far transfer to a measure of fluid intelligence did not emerge. Recording EEG during a separate WM transfer task, we examined group-specific, training-related changes in alpha power, which are proposed to be sensitive to WM demands and top-down modulation of WM. Results indicated that the dual n-back group showed significantly greater frontal alpha power after training compared to before training, more so than both other groups. However, we found no evidence of improvement on measures of relational WM for the dual n-back group, suggesting that near transfer may not be dependent on relational WM. These results suggest that dual n-back and complex span task training may differ in their effectiveness to elicit near transfer as well as in the underlying neural changes they facilitate.

  16. Dissociable Changes of Frontal and Parietal Cortices in Inherent Functional Flexibility across the Human Life Span.

    PubMed

    Yin, Dazhi; Liu, Wenjing; Zeljic, Kristina; Wang, Zhiwei; Lv, Qian; Fan, Mingxia; Cheng, Wenhong; Wang, Zheng

    2016-09-28

    Extensive evidence suggests that frontoparietal regions can dynamically update their pattern of functional connectivity, supporting cognitive control and adaptive implementation of task demands. However, it is largely unknown whether this flexibly functional reconfiguration is intrinsic and occurs even in the absence of overt tasks. Based on recent advances in dynamics of resting-state functional resonance imaging (fMRI), we propose a probabilistic framework in which dynamic reconfiguration of intrinsic functional connectivity between each brain region and others can be represented as a probability distribution. A complexity measurement (i.e., entropy) was used to quantify functional flexibility, which characterizes heterogeneous connectivity between a particular region and others over time. Following this framework, we identified both functionally flexible and specialized regions over the human life span (112 healthy subjects from 13 to 76 years old). Across brainwide regions, we found regions showing high flexibility mainly in the higher-order association cortex, such as the lateral prefrontal cortex (LPFC), lateral parietal cortex, and lateral temporal lobules. In contrast, visual, auditory, and sensory areas exhibited low flexibility. Furthermore, we observed that flexibility of the right LPFC improved during maturation and reduced due to normal aging, with the opposite occurring for the left lateral parietal cortex. Our findings reveal dissociable changes of frontal and parietal cortices over the life span in terms of inherent functional flexibility. This study not only provides a new framework to quantify the spatiotemporal behavior of spontaneous brain activity, but also sheds light on the organizational principle behind changes in brain function across the human life span. Recent neuroscientific research has demonstrated that the human capability of adaptive task control is primarily the result of the flexible operation of frontal brain networks. However, it remains unclear whether this flexibly functional reconfiguration is intrinsic and occurs in the absence of an overt task. In this study, we propose a probabilistic framework to quantify the functional flexibility of each brain region using resting-state fMRI. We identify regions showing high flexibility mainly in the higher-order association cortex. In contrast, primary and unimodal visual and sensory areas show low flexibility. On the other hand, our findings reveal dissociable changes of frontal and parietal cortices in terms of inherent functional flexibility over the life span. Copyright © 2016 the authors 0270-6474/16/3610060-15$15.00/0.

  17. Relationships between Categorical Perception of Phonemes, Phoneme Awareness, and Visual Attention Span in Developmental Dyslexia.

    PubMed

    Zoubrinetzky, Rachel; Collet, Gregory; Serniclaes, Willy; Nguyen-Morel, Marie-Ange; Valdois, Sylviane

    2016-01-01

    We tested the hypothesis that the categorical perception deficit of speech sounds in developmental dyslexia is related to phoneme awareness skills, whereas a visual attention (VA) span deficit constitutes an independent deficit. Phoneme awareness tasks, VA span tasks and categorical perception tasks of phoneme identification and discrimination using a d/t voicing continuum were administered to 63 dyslexic children and 63 control children matched on chronological age. Results showed significant differences in categorical perception between the dyslexic and control children. Significant correlations were found between categorical perception skills, phoneme awareness and reading. Although VA span correlated with reading, no significant correlations were found between either categorical perception or phoneme awareness and VA span. Mediation analyses performed on the whole dyslexic sample suggested that the effect of categorical perception on reading might be mediated by phoneme awareness. This relationship was independent of the participants' VA span abilities. Two groups of dyslexic children with a single phoneme awareness or a single VA span deficit were then identified. The phonologically impaired group showed lower categorical perception skills than the control group but categorical perception was similar in the VA span impaired dyslexic and control children. The overall findings suggest that the link between categorical perception, phoneme awareness and reading is independent from VA span skills. These findings provide new insights on the heterogeneity of developmental dyslexia. They suggest that phonological processes and VA span independently affect reading acquisition.

  18. Relationships between Categorical Perception of Phonemes, Phoneme Awareness, and Visual Attention Span in Developmental Dyslexia

    PubMed Central

    Zoubrinetzky, Rachel; Collet, Gregory; Serniclaes, Willy; Nguyen-Morel, Marie-Ange; Valdois, Sylviane

    2016-01-01

    We tested the hypothesis that the categorical perception deficit of speech sounds in developmental dyslexia is related to phoneme awareness skills, whereas a visual attention (VA) span deficit constitutes an independent deficit. Phoneme awareness tasks, VA span tasks and categorical perception tasks of phoneme identification and discrimination using a d/t voicing continuum were administered to 63 dyslexic children and 63 control children matched on chronological age. Results showed significant differences in categorical perception between the dyslexic and control children. Significant correlations were found between categorical perception skills, phoneme awareness and reading. Although VA span correlated with reading, no significant correlations were found between either categorical perception or phoneme awareness and VA span. Mediation analyses performed on the whole dyslexic sample suggested that the effect of categorical perception on reading might be mediated by phoneme awareness. This relationship was independent of the participants’ VA span abilities. Two groups of dyslexic children with a single phoneme awareness or a single VA span deficit were then identified. The phonologically impaired group showed lower categorical perception skills than the control group but categorical perception was similar in the VA span impaired dyslexic and control children. The overall findings suggest that the link between categorical perception, phoneme awareness and reading is independent from VA span skills. These findings provide new insights on the heterogeneity of developmental dyslexia. They suggest that phonological processes and VA span independently affect reading acquisition. PMID:26950210

  19. Do the effects of working memory training depend on baseline ability level?

    PubMed

    Foster, Jeffrey L; Harrison, Tyler L; Hicks, Kenny L; Draheim, Christopher; Redick, Thomas S; Engle, Randall W

    2017-11-01

    There is a debate about the ability to improve cognitive abilities such as fluid intelligence through training on tasks of working memory capacity. The question addressed in the research presented here is who benefits the most from training: people with low cognitive ability or people with high cognitive ability? Subjects with high and low working memory capacity completed a 23-session study that included 3 assessment sessions, and 20 sessions of training on 1 of 3 training regiments: complex span training, running span training, or an active-control task. Consistent with other research, the authors found that training on 1 executive function did not transfer to ability on a different cognitive ability. High working memory subjects showed the largest gains on the training tasks themselves relative to the low working memory subjects-a finding that suggests high spans benefit more than low spans from training with executive function tasks. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  20. Parallel effects of memory set activation and search on timing and working memory capacity.

    PubMed

    Schweickert, Richard; Fortin, Claudette; Xi, Zhuangzhuang; Viau-Quesnel, Charles

    2014-01-01

    Accurately estimating a time interval is required in everyday activities such as driving or cooking. Estimating time is relatively easy, provided a person attends to it. But a brief shift of attention to another task usually interferes with timing. Most processes carried out concurrently with timing interfere with it. Curiously, some do not. Literature on a few processes suggests a general proposition, the Timing and Complex-Span Hypothesis: A process interferes with concurrent timing if and only if process performance is related to complex span. Complex-span is the number of items correctly recalled in order, when each item presented for study is followed by a brief activity. Literature on task switching, visual search, memory search, word generation and mental time travel supports the hypothesis. Previous work found that another process, activation of a memory set in long term memory, is not related to complex-span. If the Timing and Complex-Span Hypothesis is true, activation should not interfere with concurrent timing in dual-task conditions. We tested such activation in single-task memory search task conditions and in dual-task conditions where memory search was executed with concurrent timing. In Experiment 1, activating a memory set increased reaction time, with no significant effect on time production. In Experiment 2, set size and memory set activation were manipulated. Activation and set size had a puzzling interaction for time productions, perhaps due to difficult conditions, leading us to use a related but easier task in Experiment 3. In Experiment 3 increasing set size lengthened time production, but memory activation had no significant effect. Results here and in previous literature on the whole support the Timing and Complex-Span Hypotheses. Results also support a sequential organization of activation and search of memory. This organization predicts activation and set size have additive effects on reaction time and multiplicative effects on percent correct, which was found.

  1. Working memory in children assessed with serial chaining and Simon tasks.

    PubMed

    Parrish, Audrey E; Perdue, Bonnie M; Kelly, Andrew J; Beran, Michael J

    2018-06-06

    In the serial chaining task, participants are required to produce a sequence of responses to stimuli in the correct order, and sometimes must determine the sequence at trial outset if stimuli are masked after the first response is made. Similarly, the Simon memory span task presents a participant with a sequence of colors, and the participant must recreate the sequence after the full series is shown. In efforts to directly link the comparative literature on sequential planning behavior and working memory span with the developmental literature, we presented preschool children with the serial chaining task using masked Arabic numerals (N = 44) and the Simon memory span task (N = 65). Older children outperformed younger children in each task, sequencing a longer string of numbers in the serial chaining task and remembering a greater number of items in the Simon task. Controlling for the role of age, there was a significant positive relationship between task scores. These results highlight the emergence of working memory skills that might underlie planning capacities in children using a task developed for nonhuman animals, and the results indicate that improvement in general executive functions could be measured using either or both of these tasks among human children and nonhuman species. Copyright © 2018 Elsevier B.V. All rights reserved.

  2. The "Middle Class" (If There Is Such a Thing): The Opinions and Moods of Young People of High Income in Russia

    ERIC Educational Resources Information Center

    Gudkov, Lev; Dubin, Boris; Zorkaia, Nataliia

    2009-01-01

    Over the span of all of the years that the Levada Center has been in operation, one of the tasks of the research collective has been to analyze the behavior of "advanced" groups whose characteristic way of life, attitudes, and assessments might have the significance, to other strata of the society, of a model, and provide them with an…

  3. How Does Consecutive Interpreting Training Influence Working Memory: A Longitudinal Study of Potential Links Between the Two

    PubMed Central

    Dong, Yanping; Liu, Yuhua; Cai, Rendong

    2018-01-01

    With an intention to contribute to the issue of how language experience may influence working memory (WM), we focused on consecutive interpreting (CI), analyzed its potential links with WM functions and tested these links in a longitudinal experiment, trying to answer the specific question of how CI training may influence WM. Two comparable groups of Chinese learners of English received either CI or general second language (L2) training for one semester, and were tested before and after the training with the tasks of n-back (non-verbal updating), L2 listening span, and letter running span (verbal spans). CI performance was tested in the posttest. The results showed that (1) updating efficiency in both the pretest and posttest predicted CI performance, and CI training enhanced updating efficiency while general L2 training did not; (2) the relationship between verbal spans and CI performance was weaker (i.e., only pretest L2 listening span correlated with CI performance and predicted CI performance with marginal significance), and CI training did not make a unique contribution to these spans (i.e., no group differences). The results indicated an “interpreter advantage” in updating, which was probably due to that updating was more central in the CI task than WM spans. Theoretically, we believe that updating and CI are closely related because they share the same underlying mechanism, or more specifically updating and the recalling process in the CI task share the same attentional control process, a unique link between updating and the CI task. Methodological implications are discussed. PMID:29922199

  4. Visual-Attentional Span and Lexical ­Decision in Skilled Adult Readers

    ERIC Educational Resources Information Center

    Holmes, Virginia M.; Dawson, Georgia

    2014-01-01

    The goal of the study was to examine the association between visual-attentional span and lexical decision in skilled adult readers. In the span tasks, an array of letters was presented briefly and recognition or production of a single cued letter (partial span) or production of all letters (whole span) was required. Independently of letter…

  5. Individual differences in working memory capacity and workload capacity.

    PubMed

    Yu, Ju-Chi; Chang, Ting-Yun; Yang, Cheng-Ta

    2014-01-01

    We investigated the relationship between working memory capacity (WMC) and workload capacity (WLC). Each participant performed an operation span (OSPAN) task to measure his/her WMC and three redundant-target detection tasks to measure his/her WLC. WLC was computed non-parametrically (Experiments 1 and 2) and parametrically (Experiment 2). Both levels of analyses showed that participants high in WMC had larger WLC than those low in WMC only when redundant information came from visual and auditory modalities, suggesting that high-WMC participants had superior processing capacity in dealing with redundant visual and auditory information. This difference was eliminated when multiple processes required processing for only a single working memory subsystem in a color-shape detection task and a double-dot detection task. These results highlighted the role of executive control in integrating and binding information from the two working memory subsystems for perceptual decision making.

  6. Working memory capacity and task goals modulate error-related ERPs.

    PubMed

    Coleman, James R; Watson, Jason M; Strayer, David L

    2018-03-01

    The present study investigated individual differences in information processing following errant behavior. Participants were initially classified as high or as low working memory capacity using the Operation Span Task. In a subsequent session, they then performed a high congruency version of the flanker task under both speed and accuracy stress. We recorded ERPs and behavioral measures of accuracy and response time in the flanker task with a primary focus on processing following an error. The error-related negativity was larger for the high working memory capacity group than for the low working memory capacity group. The positivity following an error (Pe) was modulated to a greater extent by speed-accuracy instruction for the high working memory capacity group than for the low working memory capacity group. These data help to explicate the neural bases of individual differences in working memory capacity and cognitive control. © 2017 Society for Psychophysiological Research.

  7. Cognitive performance in adolescents with Delayed Sleep-Wake Phase Disorder: Treatment effects and a comparison with good sleepers.

    PubMed

    Richardson, C; Micic, G; Cain, N; Bartel, K; Maddock, B; Gradisar, M

    2018-06-01

    The present study aimed to investigate whether Australian adolescents with Delayed Sleep-Wake Phase Disorder have impaired cognitive performance and whether chronobiological treatment for Delayed Sleep-Wake Phase Disorder improves adolescents' sleep, daytime functioning and cognitive performance. Adolescents with Delayed Sleep-Wake Phase Disorder (mean = 15.68 ± 2.1 y, 62% f) reported significantly later sleep timing (d = 1.03-1.45), less total sleep time (d = 0.82) and greater daytime sleepiness (d = 2.66), fatigue (d = 0.63) and impairment (d = 2.41), compared to good sleeping adolescents (mean = 15.9 ± 2.4 y, 75% f). However, there were no significant between-group differences (all p > 0.05) in performance on the Operation Span (ηp 2  = 0.043), Digit Span (forwards: ηp 2  = 0.002, backwards: ηp 2  = 0.003), Letter Number Sequencing (ηp 2  < 0.001) (working memory) and Digit-Symbol Substitution Tasks (ηp 2  = 0.010) (processing speed). Adolescents with Delayed Sleep-Wake Phase Disorder went on to receive 3 weeks of light therapy. At 3 months post-treatment, adolescents with Delayed Sleep-Wake Phase Disorder reported significantly advanced sleep timing (d = 0.56-0.65), greater total sleep time (d = 0.52) and improved daytime sleepiness (d = 1.33), fatigue (d = 0.84) and impairment (d = 0.78). Performance on the Operation Span (d = 0.46), Letter Number Sequencing (d = 0.45) and Digit-Symbol Substitution tasks (d = 0.57) also significantly improved. Copyright © 2018. Published by Elsevier Ltd.

  8. When does a good working memory counteract proactive interference? Surprising evidence from a probe recognition task.

    PubMed

    Cowan, Nelson; Saults, J Scott

    2013-02-01

    It is often proposed that individuals with high working memory span overcome proactive interference (PI) from previous trials, saving working memory for task-relevant items. We examined this hypothesis in word-list probe recognition. We found no difference in PI related to span. Instead, ex-gaussian analysis of reaction time showed speed advantages for high spans specific to short lists (3 or 4 items) but absent from longer lists (6 or 8 items). We suggest that high-span advantages in reaction time are based on finesse during easy trials, not on overcoming PI. 2013 APA, all rights reserved

  9. Cross-Language Modulation of Visual Attention Span: An Arabic-French-Spanish Comparison in Skilled Adult Readers.

    PubMed

    Awadh, Faris H R; Phénix, Thierry; Antzaka, Alexia; Lallier, Marie; Carreiras, Manuel; Valdois, Sylviane

    2016-01-01

    In delineating the amount of orthographic information that can be processed in parallel during a single fixation, the visual attention (VA) span acts as a key component of the reading system. Previous studies focused on the contribution of VA span to normal and pathological reading in monolingual and bilingual children from different European languages, without direct cross-language comparison. In the current paper, we explored modulations of VA span abilities in three languages -French, Spanish, and Arabic- that differ in transparency, reading direction and writing systems. The participants were skilled adult readers who were native speakers of French, Spanish or Arabic. They were administered tasks of global and partial letter report, single letter identification and text reading. Their VA span abilities were assessed using tasks that require the processing of briefly presented five consonant strings (e.g., R S H F T). All five consonants had to be reported in global report but a single cued letter in partial report. Results showed that VA span was reduced in Arabic readers as compared to French or Spanish readers who otherwise show a similar high performance in the two report tasks. The analysis of VA span response patterns in global report showed a left-right asymmetry in all three languages. A leftward letter advantage was found in French and Spanish but a rightward advantage in Arabic. The response patterns were symmetric in partial report, regardless of the language. Last, a significant relationship was found between VA span abilities and reading speed but only for French. The overall findings suggest that the size of VA span, the shape of VA span response patterns and the VA Span-reading relationship are modulated by language-specific features.

  10. Cross-Language Modulation of Visual Attention Span: An Arabic-French-Spanish Comparison in Skilled Adult Readers

    PubMed Central

    Awadh, Faris H. R.; Phénix, Thierry; Antzaka, Alexia; Lallier, Marie; Carreiras, Manuel; Valdois, Sylviane

    2016-01-01

    In delineating the amount of orthographic information that can be processed in parallel during a single fixation, the visual attention (VA) span acts as a key component of the reading system. Previous studies focused on the contribution of VA span to normal and pathological reading in monolingual and bilingual children from different European languages, without direct cross-language comparison. In the current paper, we explored modulations of VA span abilities in three languages –French, Spanish, and Arabic– that differ in transparency, reading direction and writing systems. The participants were skilled adult readers who were native speakers of French, Spanish or Arabic. They were administered tasks of global and partial letter report, single letter identification and text reading. Their VA span abilities were assessed using tasks that require the processing of briefly presented five consonant strings (e.g., R S H F T). All five consonants had to be reported in global report but a single cued letter in partial report. Results showed that VA span was reduced in Arabic readers as compared to French or Spanish readers who otherwise show a similar high performance in the two report tasks. The analysis of VA span response patterns in global report showed a left-right asymmetry in all three languages. A leftward letter advantage was found in French and Spanish but a rightward advantage in Arabic. The response patterns were symmetric in partial report, regardless of the language. Last, a significant relationship was found between VA span abilities and reading speed but only for French. The overall findings suggest that the size of VA span, the shape of VA span response patterns and the VA Span-reading relationship are modulated by language-specific features. PMID:27014125

  11. Developmental dyslexia: exploring how much phonological and visual attention span disorders are linked to simultaneous auditory processing deficits.

    PubMed

    Lallier, Marie; Donnadieu, Sophie; Valdois, Sylviane

    2013-07-01

    The simultaneous auditory processing skills of 17 dyslexic children and 17 skilled readers were measured using a dichotic listening task. Results showed that the dyslexic children exhibited difficulties reporting syllabic material when presented simultaneously. As a measure of simultaneous visual processing, visual attention span skills were assessed in the dyslexic children. We presented the dyslexic children with a phonological short-term memory task and a phonemic awareness task to quantify their phonological skills. Visual attention spans correlated positively with individual scores obtained on the dichotic listening task while phonological skills did not correlate with either dichotic scores or visual attention span measures. Moreover, all the dyslexic children with a dichotic listening deficit showed a simultaneous visual processing deficit, and a substantial number of dyslexic children exhibited phonological processing deficits whether or not they exhibited low dichotic listening scores. These findings suggest that processing simultaneous auditory stimuli may be impaired in dyslexic children regardless of phonological processing difficulties and be linked to similar problems in the visual modality.

  12. Inhibitory Processes in Young Children and Individual Variation in Short-Term Memory

    PubMed Central

    Espy, Kimberly Andrews; Bull, Rebecca

    2009-01-01

    A precise definition of executive control remains elusive, related in part to the variations among executive tasks in the nature of the task demands, which complicate the identification of test-specific versus construct-specific performance. In this study, tasks were chosen that varied in the nature of the stimulus (verbal, nonverbal), response (naming, somatic motor), conflict type (proactive interference, distraction), and inhibitory process (attention control, response suppression) required. Then performance differences were examined in 184 young children (age range = 3 years 6 months to 6 years 1 month), comparing those with high (5 or more digits) and low (3 or fewer digits) spans to determine the dependence on short-term memory. Results indicated that there was communality in inhibitory task demands across instruments, although the specific pattern of task intercorrelations varied in children with high and low spans. Furthermore, only performance on attention control tasks—that is, that require cognitive engagement/disengagement among an internally represented rule or response set that was previously active versus those currently active—differed between children of high and low spans. In contrast, there were differences neither between children with high and low spans on response suppression tasks nor on tasks when considered by type of stimulus, response, or conflict. Individual differences in well-regulated thought may rest in variations in the ability to maintain information in an active, quickly retrievable state that subserve controlling attention in a goal-relevant fashion. PMID:16144432

  13. Spatial-Sequential Working Memory in Younger and Older Adults: Age Predicts Backward Recall Performance within Both Age Groups

    PubMed Central

    Brown, Louise A.

    2016-01-01

    Working memory is vulnerable to age-related decline, but there is debate regarding the age-sensitivity of different forms of spatial-sequential working memory task, depending on their passive or active nature. The functional architecture of spatial working memory was therefore explored in younger (18–40 years) and older (64–85 years) adults, using passive and active recall tasks. Spatial working memory was assessed using a modified version of the Spatial Span subtest of the Wechsler Memory Scale – Third Edition (WMS-III; Wechsler, 1998). Across both age groups, the effects of interference (control, visual, or spatial), and recall type (forward and backward), were investigated. There was a clear effect of age group, with younger adults demonstrating a larger spatial working memory capacity than the older adults overall. There was also a specific effect of interference, with the spatial interference task (spatial tapping) reliably reducing performance relative to both the control and visual interference (dynamic visual noise) conditions in both age groups and both recall types. This suggests that younger and older adults have similar dependence upon active spatial rehearsal, and that both forward and backward recall require this processing capacity. Linear regression analyses were then carried out within each age group, to assess the predictors of performance in each recall format (forward and backward). Specifically the backward recall task was significantly predicted by age, within both the younger and older adult groups. This finding supports previous literature showing lifespan linear declines in spatial-sequential working memory, and in working memory tasks from other domains, but contrasts with previous evidence that backward spatial span is no more sensitive to aging than forward span. The study suggests that backward spatial span is indeed more processing-intensive than forward span, even when both tasks include a retention period, and that age predicts backward spatial span performance across the adult lifespan, within both younger and older adulthood. PMID:27757096

  14. Spatial-Sequential Working Memory in Younger and Older Adults: Age Predicts Backward Recall Performance within Both Age Groups.

    PubMed

    Brown, Louise A

    2016-01-01

    Working memory is vulnerable to age-related decline, but there is debate regarding the age-sensitivity of different forms of spatial-sequential working memory task, depending on their passive or active nature. The functional architecture of spatial working memory was therefore explored in younger (18-40 years) and older (64-85 years) adults, using passive and active recall tasks. Spatial working memory was assessed using a modified version of the Spatial Span subtest of the Wechsler Memory Scale - Third Edition (WMS-III; Wechsler, 1998). Across both age groups, the effects of interference (control, visual, or spatial), and recall type (forward and backward), were investigated. There was a clear effect of age group, with younger adults demonstrating a larger spatial working memory capacity than the older adults overall. There was also a specific effect of interference, with the spatial interference task (spatial tapping) reliably reducing performance relative to both the control and visual interference (dynamic visual noise) conditions in both age groups and both recall types. This suggests that younger and older adults have similar dependence upon active spatial rehearsal, and that both forward and backward recall require this processing capacity. Linear regression analyses were then carried out within each age group, to assess the predictors of performance in each recall format (forward and backward). Specifically the backward recall task was significantly predicted by age, within both the younger and older adult groups. This finding supports previous literature showing lifespan linear declines in spatial-sequential working memory, and in working memory tasks from other domains, but contrasts with previous evidence that backward spatial span is no more sensitive to aging than forward span. The study suggests that backward spatial span is indeed more processing-intensive than forward span, even when both tasks include a retention period, and that age predicts backward spatial span performance across the adult lifespan, within both younger and older adulthood.

  15. Differential recall of derived and inflected word forms in working memory: examining the role of morphological information in simple and complex working memory tasks

    PubMed Central

    Service, Elisabet; Maury, Sini

    2015-01-01

    Working memory (WM) has been described as an interface between cognition and action, or a system for access to a limited amount of information needed in complex cognition. Access to morphological information is needed for comprehending and producing sentences. The present study probed WM for morphologically complex word forms in Finnish, a morphologically rich language. We studied monomorphemic (boy), inflected (boy+’s), and derived (boy+hood) words in three tasks. Simple span, immediate serial recall of words, in Experiment 1, is assumed to mainly rely on information in the focus of attention. Sentence span, a dual task combining sentence reading with recall of the last word (Experiment 2) or of a word not included in the sentence (Experiment 3) is assumed to involve establishment of a search set in long-term memory for fast activation into the focus of attention. Recall was best for monomorphemic and worst for inflected word forms with performance on derived words in between. However, there was an interaction between word type and experiment, suggesting that complex span is more sensitive to morphological complexity in derivations than simple span. This was explored in a within-subjects Experiment 4 combining all three tasks. An interaction between morphological complexity and task was replicated. Both inflected and derived forms increased load in WM. In simple span, recall of inflectional forms resulted in form errors. Complex span tasks were more sensitive to morphological load in derived words, possibly resulting from interference from morphological neighbors in the mental lexicon. The results are best understood as involving competition among inflectional forms when binding words from input into an output structure, and competition from morphological neighbors in secondary memory during cumulative retrieval-encoding cycles. Models of verbal recall need to be able to represent morphological as well as phonological and semantic information. PMID:25642181

  16. Parents' and Teachers' Perceptions of Abnormal Attention Span of Elementary School-Age Children.

    PubMed

    Segal-Triwitz, Yael; Kirchen, Louisa M; Shani Sherman, Tal; Levav, Miriam; Schonherz-Pine, Yael; Kushnir, Jonathan; Ariel, Raya; Gothelf, Doron

    2016-01-01

    To determine teacher and parental perception of minimal expected sustained attention span during various daily tasks among elementary school children. 54 parents and 47 teachers completed the attention span questionnaire (AtSQ) that was developed for this study. The AtSQ consists of 15 academic and leisure tasks that require a child's sustained attention. The study focused on third and fourth graders in Israel. There was a high degree of variability among teachers and parents in their responses to the AtSQ. The expected attention span of children as judged by parents was higher and more varied compared to teachers, and higher for girls than for boys. Our results indicate poor agreement in cutoff values for sustained attention span between teachers and parents and within each group.

  17. Disentangling working memory processes during spatial span assessment: a modeling analysis of preferred eye movement strategies.

    PubMed

    Patt, Virginie M; Thomas, Michael L; Minassian, Arpi; Geyer, Mark A; Brown, Gregory G; Perry, William

    2014-01-01

    The neurocognitive processes involved during classic spatial working memory (SWM) assessment were investigated by examining naturally preferred eye movement strategies. Cognitively healthy adult volunteers were tested in a computerized version of the Corsi Block-Tapping Task--a spatial span task requiring the short term maintenance of a series of locations presented in a specific order--coupled with eye tracking. Modeling analysis was developed to characterize eye-tracking patterns across all task phases, including encoding, retention, and recall. Results revealed a natural preference for local gaze maintenance during both encoding and retention, with fewer than 40% fixated targets. These findings contrasted with the stimulus retracing pattern expected during recall as a result of task demands, with 80% fixated targets. Along with participants' self-reported strategies of mentally "making shapes," these results suggest the involvement of covert attention shifts and higher order cognitive Gestalt processes during spatial span tasks, challenging instrument validity as a single measure of SWM storage capacity.

  18. Individual differences in working memory, secondary memory, and fluid intelligence: evidence from the levels-of-processing span task.

    PubMed

    Rose, Nathan S

    2013-12-01

    Individual differences in working memory (WM) are related to performance on secondary memory (SM), and fluid intelligence (gF) tests. However, the source of the relation remains unclear, in part because few studies have controlled for the nature of encoding; therefore, it is unclear whether individual variation is due to encoding, maintenance, or retrieval processes. In the current study, participants performed a WM task (the levels-of-processing span task; Rose, Myerson, Roediger III, & Hale, 2010) and a SM test that tested for both targets and the distracting processing words from the initial WM task. Deeper levels of processing at encoding did not benefit WM, but did benefit subsequent SM, although the amount of benefit was smaller for those with lower WM spans. This result suggests that, despite encoding cues that facilitate retrieval from SM, low spans may have engaged in shallower, maintenance-focused processing to maintain the words in WM. Low spans also recalled fewer targets, more distractors, and more extralist intrusions than high spans, although this was partially due to low spans' poorer recall of targets, which resulted in a greater number of opportunities to commit recall errors. Delayed recall of intrusions and commission of source errors (labeling targets as processing words and vice versa) were significant negative predictors of gF. These results suggest that the ability to use source information to recall relevant information and withhold recall of irrelevant information is a critical source of both individual variation in WM and the relation between WM, SM, and gF. (PsycINFO Database Record (c) 2013 APA, all rights reserved).

  19. The development of a short domain-general measure of working memory capacity.

    PubMed

    Oswald, Frederick L; McAbee, Samuel T; Redick, Thomas S; Hambrick, David Z

    2015-12-01

    Working memory capacity is one of the most frequently measured individual difference constructs in cognitive psychology and related fields. However, implementation of complex span and other working memory measures is generally time-consuming for administrators and examinees alike. Because researchers often must manage the tension between limited testing time and measuring numerous constructs reliably, a short and effective measure of working memory capacity would often be a major practical benefit in future research efforts. The current study developed a shortened computerized domain-general measure of working memory capacity by representatively sampling items from three existing complex working memory span tasks: operation span, reading span, and symmetry span. Using a large archival data set (Study 1, N = 4,845), we developed and applied a principled strategy for developing the reduced measure, based on testing a series of confirmatory factor analysis models. Adequate fit indices from these models lent support to this strategy. The resulting shortened measure was then administered to a second independent sample (Study 2, N = 172), demonstrating that the new measure saves roughly 15 min (30%) of testing time on average, and even up to 25 min depending on the test-taker. On the basis of these initial promising findings, several directions for future research are discussed.

  20. Hyperlink Format, Categorization Abilities and Memory Span as Contributors to Deaf Users Hypertext Access

    ERIC Educational Resources Information Center

    Farjardo, Inmaculada; Arfe, Barbara; Benedetti, Patrizia; Altoe, Gianmarco

    2008-01-01

    Sixty deaf and hearing students were asked to search for goods in a Hypertext Supermarket with either graphical or textual links of high typicality, frequency, and familiarity. Additionally, they performed a picture and word categorization task and two working memory span tasks (spatial and verbal). Results showed that deaf students were faster in…

  1. Taboo: Working memory and mental control in an interactive task

    PubMed Central

    Hansen, Whitney A.; Goldinger, Stephen D.

    2014-01-01

    Individual differences in working memory (WM) predict principled variation in tasks of reasoning, response time, memory, and other abilities. Theoretically, a central function of WM is keeping task-relevant information easily accessible while suppressing irrelevant information. The present experiment was a novel study of mental control, using performance in the game Taboo as a measure. We tested effects of WM capacity on several indices, including perseveration errors (repeating previous guesses or clues) and taboo errors (saying at least part of a taboo or target word). By most measures, high-span participants were superior to low-span participants: High-spans were better at guessing answers, better at encouraging correct guesses from teammates, and less likely to either repeat themselves or produce taboo clues. Differences in taboo errors occurred only in an easy control condition. The results suggest that WM capacity predicts behavior in tasks requiring mental control, extending this finding to an interactive group setting. PMID:19827699

  2. Working memory capacity accounts for the ability to switch between object-based and location-based allocation of visual attention.

    PubMed

    Bleckley, M Kathryn; Foster, Jeffrey L; Engle, Randall W

    2015-04-01

    Bleckley, Durso, Crutchfield, Engle, and Khanna (Psychonomic Bulletin & Review, 10, 884-889, 2003) found that visual attention allocation differed between groups high or low in working memory capacity (WMC). High-span, but not low-span, subjects showed an invalid-cue cost during a letter localization task in which the letter appeared closer to fixation than the cue, but not when the letter appeared farther from fixation than the cue. This suggests that low-spans allocated attention as a spotlight, whereas high-spans allocated their attention to objects. In this study, we tested whether utilizing object-based visual attention is a resource-limited process that is difficult for low-span individuals. In the first experiment, we tested the uses of object versus location-based attention with high and low-span subjects, with half of the subjects completing a demanding secondary load task. Under load, high-spans were no longer able to use object-based visual attention. A second experiment supported the hypothesis that these differences in allocation were due to high-spans using object-based allocation, whereas low-spans used location-based allocation.

  3. Discrepancies between bilinguals' performance on the Spanish and English versions of the WAIS Digit Span task: Cross-cultural implications.

    PubMed

    López, Enrique; Steiner, Alexander J; Hardy, David J; IsHak, Waguih W; Anderson, W Brantley

    2016-01-01

    This study explored within-subjects differences in the performance of 40 bilingual participants on the English and Spanish versions of the Wechsler Adult Intelligence Scale (WAIS) Digit Span task. To test the linguistic hypothesis that individuals would perform worse in Spanish because of its syllabic demand, we compared the number of syllables correctly recalled by each participant for every correct trial. Our analysis of the correct number of syllables remembered per trial showed that participants performed significantly better (i.e., recalling more syllables) in Spanish than in English on the total score. Findings suggest the Spanish version of the Digit Span (total score) was significantly more difficult than the English version utilizing traditional scoring methods. Moreover, the Forward Trial, rather than the Backward Trial, was more likely to show group differences between both language versions. Additionally, the Spanish trials of the Digit Span were correlated with language comprehension and verbal episodic memory measures, whereas the English trials of the Digit Span were correlated with confrontational naming and verbal fluency tasks. The results suggest that more research is necessary to further investigate other cognitive factors, rather than just syllabic demand, that might contribute to performance and outcome differences on the WAIS Digit Span in Spanish-English bilinguals.

  4. Design and aerodynamic characteristics of a span morphing wing

    NASA Astrophysics Data System (ADS)

    Yu, Yuemin; Liu, Yanju; Leng, Jinsong

    2009-03-01

    Flight vehicles are often designed to function around a primary operating point such as an efficient cruise or a high maneuverability mode. Performance and efficiency deteriorate rapidly as the airplane moves towards other portions of the flight envelope. One solution to this quandary is to radically change the shape of the aircraft. This yields both improved efficiency and a larger flight envelope. This global shape change is an example of morphing aircraft . One concept of morphing is the span morphing wing in which the wingspan is varied to accommodate multiple flight regimes. This type of design allows for at least two discreet modes of the aircraft. The original configuration, in which the extensible portion of the wing is fully retracted, yields a high speed dash mode. Fully extending the wing provides the aircraft with a low speed mode tailored for fine tracking and loiter tasks. This paper discusses the design of a span morphing wing that permits a change in the aspect ratio while simultaneously supporting structural wing loads. The wing cross section is maintained by NACA 4412 rib sections . The span morphing wing was investigated in different configurations. The wing area and the aspect ratio of the span morphing wing increase as the wings pan increases. Computational aerodynamics are used to estimate the performance and dynamic characteristics of each wing shape of this span morphing wing as its wingspan is changed. Results show that in order to obtain the same lift, the conventional wing requires a larger angle of attach(AOA) than that of the span morphing wing.The lift of the span morphing wing increases as the wing span ,Mach number and AOA increases.

  5. Working memory and intraindividual variability in processing speed: A lifespan developmental and individual-differences study.

    PubMed

    Mella, Nathalie; Fagot, Delphine; Lecerf, Thierry; de Ribaupierre, Anik

    2015-04-01

    Working memory (WM) and intraindividual variability (IIV) in processing speed are both hypothesized to reflect general attentional processes. In the present study, we aimed at exploring the relationship between WM capacity and IIV in reaction times (RTs) and its possible variation with development across the lifespan. Two WM tasks and six RT tasks of varying complexity were analyzed in a sample of 539 participants, consisting of five age groups: two groups of children (9-10 and 11-12 years of age), one group of young adults, and two groups of older adults (59-69 and 70-89 years of age). Two approaches were adopted. First, low-span and high-span individuals were identified, and analyses of variance were conducted comparing these two groups within each age group and for each RT task. The results consistently showed a span effect in the youngest children and oldest adults: High-span individuals were significantly faster and less variable than low-span individuals. In contrast, in young adults no difference was observed between high- and low-span individuals, whether in terms of their means or IIV. Second, multivariate analyses were conducted on the entire set of tasks, to determine whether IIV in RTs brought different information than the mean RT. The results showed that, although very strongly correlated, the mean and IIV in speed should be kept separate in terms of how they account for individual differences in WM. Overall, our results support the assumption of a link between WM capacity and IIV in RT, more strongly so in childhood and older adulthood.

  6. Investigation of verbal and visual working memory by multi-channel time-resolved functional near-infrared spectroscopy

    NASA Astrophysics Data System (ADS)

    Contini, D.; Caffini, M.; Re, R.; Zucchelli, L.; Spinelli, L.; Basso Moro, S.; Bisconti, S.; Ferrari, M.; Quaresima, V.; Cutini, S.; Torricelli, A.

    2013-03-01

    Working memory (WM) is fundamental for a number of cognitive processes, such as comprehension, reasoning and learning. WM allows the short-term maintenance and manipulation of the information selected by attentional processes. The goal of this study was to examine by time-resolved fNIRS neural correlates of the verbal and visual WM during forward and backward digit span (DF and DB, respectively) tasks, and symbol span (SS) task. A neural dissociation was hypothesised between the maintenance and manipulation processes. In particular, a dorsolateral/ventrolateral prefrontal cortex (DLPFC/VLPFC) recruitment was expected during the DB task, whilst a lateralised involvement of Brodmann Area (BA) 10 was expected during the execution of the DF task. Thirteen subjects were monitored by a multi-channel, dual-wavelength (690 and 829 nm) time-resolved fNIRS system during 3 minutes long DF and DB tasks and 4 minutes long SS task. The participants' mean memory span was calculated for each task: DF: 6.46+/-1.05 digits; DB: 5.62+/-1.26 digits; SS: 4.69+/-1.32 symbols. No correlation was found between the span level and the heart rate data (measured by pulse oximeter). As expected, DB elicited a broad activated area, in the bilateral VLPFC and the right DLPFC, whereas a more localised activation was observed over the right hemisphere during either DF (BA 10) or SS (BA 10 and 44). The robust involvement of the DLPFC during DB, compared to DF, is compatible with previous findings and with the key role of the central executive subserving in manipulating processes.

  7. Ordered Short-Term Memory Differs in Signers and Speakers: Implications for Models of Short-Term Memory

    ERIC Educational Resources Information Center

    Bavelier, Daphne; Newport, Elissa L.; Hall, Matt; Supalla, Ted; Boutla, Mrim

    2008-01-01

    Capacity limits in linguistic short-term memory (STM) are typically measured with forward span tasks in which participants are asked to recall lists of words in the order presented. Using such tasks, native signers of American Sign Language (ASL) exhibit smaller spans than native speakers ([Boutla, M., Supalla, T., Newport, E. L., & Bavelier, D.…

  8. Contribution of Reactive and Proactive Control to Children's Working Memory Performance: Insight from Item Recall Durations in Response Sequence Planning

    ERIC Educational Resources Information Center

    Chevalier, Nicolas; James, Tiffany D.; Wiebe, Sandra A.; Nelson, Jennifer Mize; Espy, Kimberly Andrews

    2014-01-01

    The present study addressed whether developmental improvement in working memory span task performance relies upon a growing ability to proactively plan response sequences during childhood. Two hundred thirteen children completed a working memory span task in which they used a touchscreen to reproduce orally presented sequences of animal names.…

  9. When Does a Good Working Memory Counteract Proactive Interference? Surprising Evidence from a Probe Recognition Task

    ERIC Educational Resources Information Center

    Cowan, Nelson; Saults, J. Scott

    2013-01-01

    It is often proposed that individuals with high working memory span overcome proactive interference (PI) from previous trials, saving working memory for task-relevant items. We examined this hypothesis in word-list probe recognition. We found no difference in PI related to span. Instead, ex-Gaussian analysis of reaction time showed speed…

  10. The Relationship between Processing and Storage in Working Memory Span: Not Two Sides of the Same Coin

    ERIC Educational Resources Information Center

    Maehara, Yukio; Saito, Satoru

    2007-01-01

    In working memory (WM) span tests, participants maintain memory items while performing processing tasks. In this study, we examined the impact of task processing requirements on memory-storage activities, looking at the stimulus order effect and the impact of storage requirements on processing activities, testing the processing time effect in WM…

  11. Similarities and Differences Between Working Memory and Long-Term Memory: Evidence From the Levels-of-Processing Span Task

    PubMed Central

    Rose, Nathan S.; Myerson, Joel; Roediger, Henry L.; Hale, Sandra

    2010-01-01

    Two experiments compared the effects of depth of processing on working memory (WM) and long-term memory (LTM) using a levels-of-processing (LOP) span task, a newly developed WM span procedure that involves processing to-be-remembered words based on their visual, phonological, or semantic characteristics. Depth of processing had minimal effect on WM tests, yet subsequent memory for the same items on delayed tests showed the typical benefits of semantic processing. Although the difference in LOP effects demonstrates a dissociation between WM and LTM, we also found that the retrieval practice provided by recalling words on the WM task benefited long-term retention, especially for words initially recalled from supraspan lists. The latter result is consistent with the hypothesis that WM span tasks involve retrieval from secondary memory, but the LOP dissociation suggests the processes engaged by WM and LTM tests may differ. Therefore, similarities and differences between WM and LTM depend on the extent to which retrieval from secondary memory is involved and whether there is a match (or mismatch) between initial processing and subsequent retrieval, consistent with transfer-appropriate-processing theory. PMID:20192543

  12. Task-evoked pupillometry provides a window into the development of short-term memory capacity.

    PubMed

    Johnson, Elizabeth L; Miller Singley, Alison T; Peckham, Andrew D; Johnson, Sheri L; Bunge, Silvia A

    2014-01-01

    The capacity to keep multiple items in short-term memory (STM) improves over childhood and provides the foundation for the development of multiple cognitive abilities. The goal of this study was to measure the extent to which age differences in STM capacity are related to differences in task engagement during encoding. Children (n = 69, mean age = 10.6 years) and adults (n = 54, mean age = 27.5 years) performed two STM tasks: the forward digit span test from the Wechsler Intelligence Scale for Children (WISC) and a novel eyetracking digit span task designed to overload STM capacity. Building on prior research showing that task-evoked pupil dilation can be used as a real-time index of task engagement, we measured changes in pupil dilation while participants encoded long sequences of digits for subsequent recall. As expected, adults outperformed children on both STM tasks. We found similar patterns of pupil dilation while children and adults listened to the first six digits on our STM overload task, after which the adults' pupils continued to dilate and the children's began to constrict, suggesting that the children had reached their cognitive limits and that they had begun to disengage from the task. Indeed, the point at which pupil dilation peaked at encoding was a significant predictor of WISC forward span, and this relationship held even after partialing out recall performance on the STM overload task. These findings indicate that sustained task engagement at encoding is an important component of the development of STM.

  13. The effect of orthographic neighborhood in the reading span task.

    PubMed

    Robert, Christelle; Postal, Virginie; Mathey, Stéphanie

    2015-04-01

    This study aimed at examining whether and to what extent orthographic neighborhood of words influences performance in a working memory span task. Twenty-five participants performed a reading span task in which final words to be memorized had either no higher frequency orthographic neighbor or at least one. In both neighborhood conditions, each participant completed three series of two, three, four, or five sentences. Results indicated an interaction between orthographic neighborhood and list length. In particular, an inhibitory effect of orthographic neighborhood on recall appeared in list length 5. A view is presented suggesting that words with higher frequency neighbors require more resources to be memorized than words with no such neighbors. The implications of the results are discussed with regard to memory processes and current models of visual word recognition.

  14. Robust relationship between reading span and speech recognition in noise

    PubMed Central

    Souza, Pamela; Arehart, Kathryn

    2015-01-01

    Objective Working memory refers to a cognitive system that manages information processing and temporary storage. Recent work has demonstrated that individual differences in working memory capacity measured using a reading span task are related to ability to recognize speech in noise. In this project, we investigated whether the specific implementation of the reading span task influenced the strength of the relationship between working memory capacity and speech recognition. Design The relationship between speech recognition and working memory capacity was examined for two different working memory tests that varied in approach, using a within-subject design. Data consisted of audiometric results along with the two different working memory tests; one speech-in-noise test; and a reading comprehension test. Study sample The test group included 94 older adults with varying hearing loss and 30 younger adults with normal hearing. Results Listeners with poorer working memory capacity had more difficulty understanding speech in noise after accounting for age and degree of hearing loss. That relationship did not differ significantly between the two different implementations of reading span. Conclusions Our findings suggest that different implementations of a verbal reading span task do not affect the strength of the relationship between working memory capacity and speech recognition. PMID:25975360

  15. Robust relationship between reading span and speech recognition in noise.

    PubMed

    Souza, Pamela; Arehart, Kathryn

    2015-01-01

    Working memory refers to a cognitive system that manages information processing and temporary storage. Recent work has demonstrated that individual differences in working memory capacity measured using a reading span task are related to ability to recognize speech in noise. In this project, we investigated whether the specific implementation of the reading span task influenced the strength of the relationship between working memory capacity and speech recognition. The relationship between speech recognition and working memory capacity was examined for two different working memory tests that varied in approach, using a within-subject design. Data consisted of audiometric results along with the two different working memory tests; one speech-in-noise test; and a reading comprehension test. The test group included 94 older adults with varying hearing loss and 30 younger adults with normal hearing. Listeners with poorer working memory capacity had more difficulty understanding speech in noise after accounting for age and degree of hearing loss. That relationship did not differ significantly between the two different implementations of reading span. Our findings suggest that different implementations of a verbal reading span task do not affect the strength of the relationship between working memory capacity and speech recognition.

  16. How does running memory span work?

    PubMed

    Bunting, Michael; Cowan, Nelson; Saults, J Scott

    2006-10-01

    In running memory span, a list ends unpredictably, and the last few items are to be recalled. This task is of increasing importance in recent research. We argue that there are two very different strategies for performing running span tasks: a low-effort strategy in which items are passively held until the list ends, when retrieval into a capacity-limited store takes place; and a higher-effort strategy in which working memory is continually updated using rehearsal processes during the list presentation. In two experiments, we examine the roles of these two strategies and the consequences of two types of interference.

  17. Working memory capacity and the scope and control of attention.

    PubMed

    Shipstead, Zach; Harrison, Tyler L; Engle, Randall W

    2015-08-01

    Complex span and visual arrays are two common measures of working memory capacity that are respectively treated as measures of attention control and storage capacity. A recent analysis of these tasks concluded that (1) complex span performance has a relatively stronger relationship to fluid intelligence and (2) this is due to the requirement that people engage control processes while performing this task. The present study examines the validity of these conclusions by examining two large data sets that include a more diverse set of visual arrays tasks and several measures of attention control. We conclude that complex span and visual arrays account for similar amounts of variance in fluid intelligence. The disparity relative to the earlier analysis is attributed to the present study involving a more complete measure of the latent ability underlying the performance of visual arrays. Moreover, we find that both types of working memory task have strong relationships to attention control. This indicates that the ability to engage attention in a controlled manner is a critical aspect of working memory capacity, regardless of the type of task that is used to measure this construct.

  18. Individual differences in working memory and reasoning-remembering relationships in solving class-inclusion problems.

    PubMed

    Howe, M L; Rabinowitz, F M; Powell, T L

    1998-09-01

    In the present experiment, we evaluated the effects of individual differences in reading span and variation in memory demands on class-inclusion performance. One hundred twenty college students whose reading spans ranged from low to medium to high (as indexed by a computerized version of the Daneman and Carpenter [1980] reading-span task) solved 48 class-inclusion problems. Half of the subjects had the solution information available when the problems were presented; the other half performed a detection task between solution information and problem presentation. The results from both standard statistical analyses and from a mathematical model indicated that differences in reading span and memory load had predictable, similar effects. Specifically, the sophistication of reasoning strategies declined when memory demands increased or when reading spans decreased. Surprisingly, these effects were primarily additive. The results were interpreted in terms of global resource models and findings from the developmental literature.

  19. The Developmental Influence of Primary Memory Capacity on Working Memory and Academic Achievement

    PubMed Central

    2015-01-01

    In this study, we investigate the development of primary memory capacity among children. Children between the ages of 5 and 8 completed 3 novel tasks (split span, interleaved lists, and a modified free-recall task) that measured primary memory by estimating the number of items in the focus of attention that could be spontaneously recalled in serial order. These tasks were calibrated against traditional measures of simple and complex span. Clear age-related changes in these primary memory estimates were observed. There were marked individual differences in primary memory capacity, but each novel measure was predictive of simple span performance. Among older children, each measure shared variance with reading and mathematics performance, whereas for younger children, the interleaved lists task was the strongest single predictor of academic ability. We argue that these novel tasks have considerable potential for the measurement of primary memory capacity and provide new, complementary ways of measuring the transient memory processes that predict academic performance. The interleaved lists task also shared features with interference control tasks, and our findings suggest that young children have a particular difficulty in resisting distraction and that variance in the ability to resist distraction is also shared with measures of educational attainment. PMID:26075630

  20. The developmental influence of primary memory capacity on working memory and academic achievement.

    PubMed

    Hall, Debbora; Jarrold, Christopher; Towse, John N; Zarandi, Amy L

    2015-08-01

    In this study, we investigate the development of primary memory capacity among children. Children between the ages of 5 and 8 completed 3 novel tasks (split span, interleaved lists, and a modified free-recall task) that measured primary memory by estimating the number of items in the focus of attention that could be spontaneously recalled in serial order. These tasks were calibrated against traditional measures of simple and complex span. Clear age-related changes in these primary memory estimates were observed. There were marked individual differences in primary memory capacity, but each novel measure was predictive of simple span performance. Among older children, each measure shared variance with reading and mathematics performance, whereas for younger children, the interleaved lists task was the strongest single predictor of academic ability. We argue that these novel tasks have considerable potential for the measurement of primary memory capacity and provide new, complementary ways of measuring the transient memory processes that predict academic performance. The interleaved lists task also shared features with interference control tasks, and our findings suggest that young children have a particular difficulty in resisting distraction and that variance in the ability to resist distraction is also shared with measures of educational attainment. (c) 2015 APA, all rights reserved).

  1. Influence of Pharmacological Manipulations of NMDA and Cholinergic Receptors on Working versus Reference Memory in a Dual Component Odor Span Task

    ERIC Educational Resources Information Center

    MacQueen, David A.; Dalrymple, Savannah R.; Drobes, David J.; Diamond, David M.

    2016-01-01

    Developed as a tool to assess working memory capacity in rodents, the odor span task (OST) has significant potential to advance drug discovery in animal models of psychiatric disorders. Prior investigations indicate OST performance is impaired by systemic administration of N-methyl-D-aspartate receptor (NMDA-r) antagonists and is sensitive to…

  2. Working memory and the strategic control of attention in older and younger adults.

    PubMed

    Hayes, Melissa G; Kelly, Andrew J; Smith, Anderson D

    2013-03-01

    The objective of this study was to investigate the effects of aging on the strategic control of attention and the extent to which this relationship is mediated by working memory capacity (WMC). This study also sought to investigate boundary conditions wherein age differences in selectivity may occur. Across 2 studies, the value-directed remembering task used by Castel and colleagues (Castel, A. D., Balota, D. A., & McCabe, D. P. (2009). Memory efficiency and the strategic control of attention at encoding: Impairments of value-directed remembering in Alzheimer's Disease. Neuropsychology, 23, 297-306) was modified to include value-directed forgetting. Study 2 incorporated valence as an additional task demand, and age differences were predicted in both studies due to increased demands of controlled processing. Automated operation span and Stroop span were included as working memory measures, and working memory was predicted to mediate performance. Results confirmed these predictions, as older adults were less efficient in maximizing selectivity scores when high demands were placed on selectivity processes, and working memory was found to mediate performance on this task. When list length was increased from previous studies and participants were required to actively forget negative-value words, older adults were not able to selectively encode high-value information to the same degree as younger adults. Furthermore, WMC appears to support the ability to selectively encode information.

  3. Phonological similarity in working memory span tasks.

    PubMed

    Chow, Michael; Macnamara, Brooke N; Conway, Andrew R A

    2016-08-01

    In a series of four experiments, we explored what conditions are sufficient to produce a phonological similarity facilitation effect in working memory span tasks. By using the same set of memoranda, but differing the secondary-task requirements across experiments, we showed that a phonological similarity facilitation effect is dependent upon the semantic relationship between the memoranda and the secondary-task stimuli, and is robust to changes in the representation, ordering, and pool size of the secondary-task stimuli. These findings are consistent with interference accounts of memory (Brown, Neath, & Chater, Psychological Review, 114, 539-576, 2007; Oberauer, Lewandowsky, Farrell, Jarrold, & Greaves, Psychonomic Bulletin & Review, 19, 779-819, 2012), whereby rhyming stimuli provide a form of categorical similarity that allows distractors to be excluded from retrieval at recall.

  4. Choose and choose again: appearance-reality errors, pragmatics and logical ability.

    PubMed

    Deák, Gedeon O; Enright, Brian

    2006-05-01

    In the Appearance/Reality (AR) task some 3- and 4-year-old children make perseverative errors: they choose the same word for the appearance and the function of a deceptive object. Are these errors specific to the AR task, or signs of a general question-answering problem? Preschoolers completed five tasks: AR; simple successive forced-choice question pairs (QP); flexible naming of objects (FN); working memory (WM) span; and indeterminacy detection (ID). AR errors correlated with QP errors. Insensitivity to indeterminacy predicted perseveration in both tasks. Neither WM span nor flexible naming predicted other measures. Age predicted sensitivity to indeterminacy. These findings suggest that AR tests measure a pragmatic understanding; specifically, different questions about a topic usually call for different answers. This understanding is related to the ability to detect indeterminacy of each question in a series. AR errors are unrelated to the ability to represent an object as belonging to multiple categories, to working memory span, or to inhibiting previously activated words.

  5. Feasibility study for the implementation of NASTRAN on the ILLIAC 4 parallel processor

    NASA Technical Reports Server (NTRS)

    Field, E. I.

    1975-01-01

    The ILLIAC IV, a fourth generation multiprocessor using parallel processing hardware concepts, is operational at Moffett Field, California. Its capability to excel at matrix manipulation, makes the ILLIAC well suited for performing structural analyses using the finite element displacement method. The feasibility of modifying the NASTRAN (NASA structural analysis) computer program to make effective use of the ILLIAC IV was investigated. The characteristics are summarized of the ILLIAC and the ARPANET, a telecommunications network which spans the continent making the ILLIAC accessible to nearly all major industrial centers in the United States. Two distinct approaches are studied: retaining NASTRAN as it now operates on many of the host computers of the ARPANET to process the input and output while using the ILLIAC only for the major computational tasks, and installing NASTRAN to operate entirely in the ILLIAC environment. Though both alternatives offer similar and significant increases in computational speed over modern third generation processors, the full installation of NASTRAN on the ILLIAC is recommended. Specifications are presented for performing that task with manpower estimates and schedules to correspond.

  6. Task-evoked pupillometry provides a window into the development of short-term memory capacity

    PubMed Central

    Johnson, Elizabeth L.; Miller Singley, Alison T.; Peckham, Andrew D.; Johnson, Sheri L.; Bunge, Silvia A.

    2014-01-01

    The capacity to keep multiple items in short-term memory (STM) improves over childhood and provides the foundation for the development of multiple cognitive abilities. The goal of this study was to measure the extent to which age differences in STM capacity are related to differences in task engagement during encoding. Children (n = 69, mean age = 10.6 years) and adults (n = 54, mean age = 27.5 years) performed two STM tasks: the forward digit span test from the Wechsler Intelligence Scale for Children (WISC) and a novel eyetracking digit span task designed to overload STM capacity. Building on prior research showing that task-evoked pupil dilation can be used as a real-time index of task engagement, we measured changes in pupil dilation while participants encoded long sequences of digits for subsequent recall. As expected, adults outperformed children on both STM tasks. We found similar patterns of pupil dilation while children and adults listened to the first six digits on our STM overload task, after which the adults' pupils continued to dilate and the children's began to constrict, suggesting that the children had reached their cognitive limits and that they had begun to disengage from the task. Indeed, the point at which pupil dilation peaked at encoding was a significant predictor of WISC forward span, and this relationship held even after partialing out recall performance on the STM overload task. These findings indicate that sustained task engagement at encoding is an important component of the development of STM. PMID:24659980

  7. Validation of the human odor span task: effects of nicotine.

    PubMed

    MacQueen, David A; Drobes, David J

    2017-10-01

    Amongst non-smokers, nicotine generally enhances performance on tasks of attention, with limited effect on working memory. In contrast, nicotine has been shown to produce robust enhancements of working memory in non-humans. To address this gap, the present study investigated the effects of nicotine on the performance of non-smokers on a cognitive battery which included a working memory task reverse-translated from use with rodents (the odor span task, OST). Nicotine has been reported to enhance OST performance in rats and the present study assessed whether this effect generalizes to human performance. Thirty non-smokers were tested on three occasions after consuming either placebo, 2 mg, or 4 mg nicotine gum. On each occasion, participants completed a battery of clinical and experimental tasks of working memory and attention. Nicotine was associated with dose-dependent enhancements in sustained attention, as evidenced by increased hit accuracy on the rapid visual information processing (RVIP) task. However, nicotine failed to produce main effects on OST performance or on alternative measures of working memory (digit span, spatial span, letter-number sequencing, 2-back) or attention (digits forward, 0-back). Interestingly, enhancement of RVIP performance occurred concomitant to significant reductions in self-reported attention/concentration. Human OST performance was significantly related to N-back performance, and as in rodents, OST accuracy declined with increasing memory load. Given the similarity of human and rodent OST performance under baseline conditions and the strong association between OST and visual 0-back accuracy, the OST may be particular useful in the study of conditions characterized by inattention.

  8. A parallel algorithm for the initial screening of space debris collisions prediction using the SGP4/SDP4 models and GPU acceleration

    NASA Astrophysics Data System (ADS)

    Lin, Mingpei; Xu, Ming; Fu, Xiaoyu

    2017-05-01

    Currently, a tremendous amount of space debris in Earth's orbit imperils operational spacecraft. It is essential to undertake risk assessments of collisions and predict dangerous encounters in space. However, collision predictions for an enormous amount of space debris give rise to large-scale computations. In this paper, a parallel algorithm is established on the Compute Unified Device Architecture (CUDA) platform of NVIDIA Corporation for collision prediction. According to the parallel structure of NVIDIA graphics processors, a block decomposition strategy is adopted in the algorithm. Space debris is divided into batches, and the computation and data transfer operations of adjacent batches overlap. As a consequence, the latency to access shared memory during the entire computing process is significantly reduced, and a higher computing speed is reached. Theoretically, a simulation of collision prediction for space debris of any amount and for any time span can be executed. To verify this algorithm, a simulation example including 1382 pieces of debris, whose operational time scales vary from 1 min to 3 days, is conducted on Tesla C2075 of NVIDIA. The simulation results demonstrate that with the same computational accuracy as that of a CPU, the computing speed of the parallel algorithm on a GPU is 30 times that on a CPU. Based on this algorithm, collision prediction of over 150 Chinese spacecraft for a time span of 3 days can be completed in less than 3 h on a single computer, which meets the timeliness requirement of the initial screening task. Furthermore, the algorithm can be adapted for multiple tasks, including particle filtration, constellation design, and Monte-Carlo simulation of an orbital computation.

  9. A Comparison of Laboratory and Clinical Working Memory Tests and Their Prediction of Fluid Intelligence

    PubMed Central

    Shelton, Jill T.; Elliott, Emily M.; Hill, B. D.; Calamia, Matthew R.; Gouvier, Wm. Drew

    2010-01-01

    The working memory (WM) construct is conceptualized similarly across domains of psychology, yet the methods used to measure WM function vary widely. The present study examined the relationship between WM measures used in the laboratory and those used in applied settings. A large sample of undergraduates completed three laboratory-based WM measures (operation span, listening span, and n-back), as well as the WM subtests from the Wechsler Adult Intelligence Scale-III and the Wechsler Memory Scale-III. Performance on all of the WM subtests of the clinical batteries shared positive correlations with the lab measures; however, the Arithmetic and Spatial Span subtests shared lower correlations than the other WM tests. Factor analyses revealed that a factor comprising scores from the three lab WM measures and the clinical subtest, Letter-Number Sequencing (LNS), provided the best measurement of WM. Additionally, a latent variable approach was taken using fluid intelligence as a criterion construct to further discriminate between the WM tests. The results revealed that the lab measures, along with the LNS task, were the best predictors of fluid abilities. PMID:20161647

  10. Development of a German reading span test with dual task design for application in cognitive hearing research.

    PubMed

    Carroll, Rebecca; Meis, Markus; Schulte, Michael; Vormann, Matthias; Kießling, Jürgen; Meister, Hartmut

    2015-02-01

    To report the development of a standardized German version of a reading span test (RST) with a dual task design. Special attention was paid to psycholinguistic control of the test items and time-sensitive scoring. We aim to establish our RST version to use for determining an individual's working memory in the framework of hearing research in German contexts. RST stimuli were controlled and pretested for psycholinguistic factors. The RST task was to read sentences, quickly determine their plausibility, and later recall certain words to determine a listener's individual reading span. RST results were correlated with outcomes of additional sentence-in-noise tests measured in an aided and an unaided listening condition, each at two reception thresholds. Item plausibility was pre-determined by 28 native German participants. An additional 62 listeners (45-86 years, M = 69.8) with mild-to-moderate hearing loss were tested for speech intelligibility and reading span in a multicenter study. The reading span test significantly correlated with speech intelligibility at both speech reception thresholds in the aided listening condition. Our German RST is standardized with respect to psycholinguistic construction principles of the stimuli, and is a cognitive correlate of intelligibility in a German matrix speech-in-noise test.

  11. Older adults do not notice their names: a new twist to a classic attention task.

    PubMed

    Naveh-Benjamin, Moshe; Kilb, Angela; Maddox, Geoffrey B; Thomas, Jenna; Fine, Hope C; Chen, Tina; Cowan, Nelson

    2014-11-01

    Although working memory spans are, on average, lower for older adults than young adults, we demonstrate in 5 experiments a way in which older adults paradoxically resemble higher capacity young adults. Specifically, in a selective-listening task, older adults almost always failed to notice their names presented in an unattended channel. This is an exaggeration of what high-span young adults show and the opposite of what low-span young adults show. This striking finding in older adults remained significant after controlling for working memory span and for noticing their names in an attended channel. The findings were replicated when presentation rate was slowed and when the ear in which the unattended name was presented was controlled. These results point to an account of older adults' performance involving not only an inhibition factor, which allows high-span young adults to suppress the channel to be ignored, but also an attentional capacity factor, with more unallocated capacity. This capacity allows low-span young adults to notice their names much more often than older adults with comparably low working memory spans do. PsycINFO Database Record (c) 2014 APA, all rights reserved.

  12. Effects of Skill Training on Working Memory Capacity

    ERIC Educational Resources Information Center

    Lee, Yuh-shiow; Lu, Min-ju; Ko, Hsiu-ping

    2007-01-01

    In this study we examined the effects of skill training, in particular mental abacus and music training, on working memory. Two groups of participants--children who had received mental abacus training and their controls--participated in Experiment 1. All participants performed the following span tasks: forward digit span, backward digit span,…

  13. Processing Efficiency in Preschoolers' Memory Span: Individual Differences Related to Age and Anxiety

    ERIC Educational Resources Information Center

    Visu-Petra, Laura; Miclea, Mircea; Cheie, Lavinia; Benga, Oana

    2009-01-01

    In self-paced auditory memory span tasks, the microanalysis of response timing measures represents a developmentally sensitive measure, providing insights into the development of distinct processing rates during recall performance. The current study first examined the effects of age and trait anxiety on span accuracy (effectiveness) and response…

  14. Neural Mechanisms of Interference Control Underlie the Relationship Between Fluid Intelligence and Working Memory Span

    PubMed Central

    Burgess, Gregory C.; Gray, Jeremy R.; Conway, Andrew R. A.; Braver, Todd S.

    2014-01-01

    Fluid intelligence (gF) and working memory (WM) span predict success in demanding cognitive situations. Recent studies show that much of the variance in gF and WM span is shared, suggesting common neural mechanisms. This study provides a direct investigation of the degree to which shared variance in gF and WM span can be explained by neural mechanisms of interference control. We measured performance and fMRI activity in 102 participants during the n-back WM task, focusing on the selective activation effects associated with high-interference lure trials. Brain activity on these trials was correlated with gF, WM span, and task performance in core brain regions linked to WM and executive control, including bilateral dorsolateral PFC (middle frontal gyrus, BA9) and parietal cortex (inferior parietal cortex; BA 40/7). Interference-related performance and interference-related activity accounted for a significant proportion of the shared variance in gF and WM span. Path analyses indicate that interference control activity may affect gF through a common set of processes that also influence WM span. These results suggest that individual differences in interference control mechanisms are important for understanding the relationship between gF and WM span. PMID:21787103

  15. How to enhance route learning and visuo-spatial working memory in aging: a training for residential care home residents.

    PubMed

    Mitolo, Micaela; Borella, Erika; Meneghetti, Chiara; Carbone, Elena; Pazzaglia, Francesca

    2017-05-01

    This study aimed to assess the efficacy of a route-learning training in a group of older adults living in a residential care home. We verified the presence of training-specific effects in tasks similar to those trained - route-learning tasks - as well as transfer effects on related cognitive processes - visuo-spatial short-term memory (VSSTM; Corsi Blocks Test (CBT), forward version), visuo-spatial working memory (VSWM; CBT, backward version; Pathway Span Tasks; Jigsaw Puzzle Test) - and in self-report measures. The maintenance of training benefits was examined after 3 months. Thirty 70-90-year-old residential care home residents were randomly assigned to the route-learning training group or to an active control group (involved in non-visuo-spatial activities). The trained group performed better than the control group in the route-learning tasks, retaining this benefit 3 months later. Immediate transfer effects were also seen in visuo-spatial span tasks (i.e., CBT forward and backward version and Pathway Span Task); these benefits had been substantially maintained at the 3-month follow-up. These findings suggest that a training on route learning is a promising approach to sustain older adults' environmental learning and some related abilities (e.g., VSSTM and VSWM), even in residential care home residents.

  16. The effects of environmental support and secondary tasks on visuospatial working memory.

    PubMed

    Lilienthal, Lindsey; Hale, Sandra; Myerson, Joel

    2014-10-01

    In the present experiments, we examined the effects of environmental support on participants' ability to rehearse locations and the role of such support in the effects of secondary tasks on memory span. In Experiment 1, the duration of interitem intervals and the presence of environmental support for visuospatial rehearsal (i.e., the array of possible memory locations) during the interitem intervals were both manipulated across four tasks. When support was provided, memory spans increased as the interitem interval durations increased, consistent with the hypothesis that environmental support facilitates rehearsal. In contrast, when environmental support was not provided, spans decreased as the duration of the interitem intervals increased, consistent with the hypothesis that visuospatial memory representations decay when rehearsal is impeded. In Experiment 2, the ratio of interitem interval duration to intertrial interval duration was kept the same on all four tasks, in order to hold temporal distinctiveness constant, yet forgetting was still observed in the absence of environmental support, consistent with the decay hypothesis. In Experiment 3, the effects of impeding rehearsal were compared to the effects of verbal and visuospatial secondary processing tasks. Forgetting of locations was greater when presentation of to-be-remembered locations alternated with the performance of a secondary task than when rehearsal was impeded by the absence of environmental support. The greatest forgetting occurred when a secondary task required the processing visuospatial information, suggesting that in addition to decay, both domain-specific and domain-general effects contribute to forgetting on visuospatial working memory tasks.

  17. The Effects of Environmental Support and Secondary Tasks on Visuospatial Working Memory

    PubMed Central

    Lilienthal, Lindsey; Hale, Sandra; Myerson, Joel

    2014-01-01

    The present experiments examined the effects of environmental support on participants’ ability to rehearse locations and its role in the effects of secondary tasks on memory span. In Experiment 1, the duration of inter-item intervals and the presence of environmental support for visuospatial rehearsal (i.e., the array of possible memory locations) during the inter-item intervals were both manipulated across four tasks. When support was provided, memory spans increased as the inter-item interval durations increased, consistent with the hypothesis that environmental support facilitates rehearsal. In contrast, when environmental support was not provided, spans decreased as the duration of the inter-item intervals increased, consistent with the hypothesis that visuospatial memory representations decay when rehearsal is impeded. In Experiment 2, the ratio of inter-item interval duration to inter-trial interval duration was kept the same on all four tasks in order to hold temporal distinctiveness constant, yet forgetting was still observed in the absence of environmental support, consistent with the decay hypothesis. In Experiment 3, the effects of impeding rehearsal were compared to the effects of verbal and visuospatial secondary processing tasks. Forgetting of locations was greater when presentation of to-be-remembered locations alternated with performance of a secondary task than when rehearsal was impeded by the absence of environmental support. The greatest forgetting occurred when a secondary task required processing visuospatial information, suggesting that in addition to decay, both domain-specific and domain-general effects contribute to forgetting on visuospatial working memory tasks. PMID:24874509

  18. EEG correlates of task engagement and mental workload in vigilance, learning, and memory tasks.

    PubMed

    Berka, Chris; Levendowski, Daniel J; Lumicao, Michelle N; Yau, Alan; Davis, Gene; Zivkovic, Vladimir T; Olmstead, Richard E; Tremoulet, Patrice D; Craven, Patrick L

    2007-05-01

    The ability to continuously and unobtrusively monitor levels of task engagement and mental workload in an operational environment could be useful in identifying more accurate and efficient methods for humans to interact with technology. This information could also be used to optimize the design of safer, more efficient work environments that increase motivation and productivity. The present study explored the feasibility of monitoring electroencephalo-graphic (EEG) indices of engagement and workload acquired unobtrusively and quantified during performance of cognitive tests. EEG was acquired from 80 healthy participants with a wireless sensor headset (F3-F4,C3-C4,Cz-POz,F3-Cz,Fz-C3,Fz-POz) during tasks including: multi-level forward/backward-digit-span, grid-recall, trails, mental-addition, 20-min 3-Choice Vigilance, and image-learning and memory tests. EEG metrics for engagement and workload were calculated for each 1 -s of EEG. Across participants, engagement but not workload decreased over the 20-min vigilance test. Engagement and workload were significantly increased during the encoding period of verbal and image-learning and memory tests when compared with the recognition/ recall period. Workload but not engagement increased linearly as level of difficulty increased in forward and backward-digit-span, grid-recall, and mental-addition tests. EEG measures correlated with both subjective and objective performance metrics. These data in combination with previous studies suggest that EEG engagement reflects information-gathering, visual processing, and allocation of attention. EEG workload increases with increasing working memory load and during problem solving, integration of information, analytical reasoning, and may be more reflective of executive functions. Inspection of EEG on a second-by-second timescale revealed associations between workload and engagement levels when aligned with specific task events providing preliminary evidence that second-by-second classifications reflect parameters of task performance.

  19. Positive affect improves working memory: implications for controlled cognitive processing.

    PubMed

    Yang, Hwajin; Yang, Sujin; Isen, Alice M

    2013-01-01

    This study examined the effects of positive affect on working memory (WM) and short-term memory (STM). Given that WM involves both storage and controlled processing and that STM primarily involves storage processing, we hypothesised that if positive affect facilitates controlled processing, it should improve WM more than STM. The results demonstrated that positive affect, compared with neutral affect, significantly enhanced WM, as measured by the operation span task. The influence of positive affect on STM, however, was weaker. These results suggest that positive affect enhances WM, a task that involves controlled processing, not just storage processing. Additional analyses of recall and processing times and accuracy further suggest that improved WM under positive affect is not attributable to motivational differences, but results instead from improved controlled cognitive processing.

  20. Time Span of Discretion and Administrative Work in School Systems: Results of a Pilot Study.

    ERIC Educational Resources Information Center

    Allison, Derek J.; Morfitt, Grace

    This paper presents findings of a study that utilized Elliott Jaques' theories of organizational depth structure and time span of discretion in administrative work to examine administrators' responsibilities in two Ontario (Canada) school systems. The theory predicts that the time-span of discretion associated with the administrative tasks will…

  1. Phonological similarity effect in complex span task.

    PubMed

    Camos, Valérie; Mora, Gérôme; Barrouillet, Pierre

    2013-01-01

    The aim of our study was to test the hypothesis that two systems are involved in verbal working memory; one is specifically dedicated to the maintenance of phonological representations through verbal rehearsal while the other would maintain multimodal representations through attentional refreshing. This theoretical framework predicts that phonologically related phenomena such as the phonological similarity effect (PSE) should occur when the domain-specific system is involved in maintenance, but should disappear when concurrent articulation hinders its use. Impeding maintenance in the domain-general system by a concurrent attentional demand should impair recall performance without affecting PSE. In three experiments, we manipulated the concurrent articulation and the attentional demand induced by the processing component of complex span tasks in which participants had to maintain lists of either similar or dissimilar words. Confirming our predictions, PSE affected recall performance in complex span tasks. Although both the attentional demand and the articulatory requirement of the concurrent task impaired recall, only the induction of an articulatory suppression during maintenance made the PSE disappear. These results suggest a duality in the systems devoted to verbal maintenance in the short term, constraining models of working memory.

  2. Long-term associative learning predicts verbal short-term memory performance.

    PubMed

    Jones, Gary; Macken, Bill

    2018-02-01

    Studies using tests such as digit span and nonword repetition have implicated short-term memory across a range of developmental domains. Such tests ostensibly assess specialized processes for the short-term manipulation and maintenance of information that are often argued to enable long-term learning. However, there is considerable evidence for an influence of long-term linguistic learning on performance in short-term memory tasks that brings into question the role of a specialized short-term memory system separate from long-term knowledge. Using natural language corpora, we show experimentally and computationally that performance on three widely used measures of short-term memory (digit span, nonword repetition, and sentence recall) can be predicted from simple associative learning operating on the linguistic environment to which a typical child may have been exposed. The findings support the broad view that short-term verbal memory performance reflects the application of long-term language knowledge to the experimental setting.

  3. Drunk, but not blind: the effects of alcohol intoxication on change blindness.

    PubMed

    Colflesh, Gregory J H; Wiley, Jennifer

    2013-03-01

    Alcohol use has long been assumed to alter cognition via attentional processes. To better understand the cognitive consequences of intoxication, the present study tested the effects of moderate intoxication (average BAC between .071 and .082) on attentional processing using complex working memory capacity (WMC) span tasks and a change blindness task. Intoxicated and sober participants were matched on baseline WMC performance, and intoxication significantly decreased performance on the complex span tasks. Surprisingly, intoxication improved performance on the change blindness task. The results are interpreted as evidence that intoxication decreases attentional control, causing either a shift towards more passive processing and/or a more diffuse attentional state. This may result in decreased performance on tasks where attentional control or focus are required, but may actually facilitate performance in some contexts. Copyright © 2013 Elsevier Inc. All rights reserved.

  4. Improved Cognition While Cycling in Parkinson’s Disease Patients and Healthy Adults

    PubMed Central

    Hazamy, Audrey A.; Altmann, Lori J. P.; Stegemöller, Elizabeth; Bowers, Dawn; Lee, Hyo Keun; Wilson, Jonathan; Okun, Michael S.; Hass, Chris J.

    2017-01-01

    Persons with Parkinson’s disease (PD) are typically more susceptible than healthy adults to impaired performance when two tasks (dual task interference) are performed simultaneously. This limitation has by many experts been attributed to limitations in cognitive resources. Nearly all studies of dual task performance in PD employ walking or balance-based motor tasks, which are commonly impaired in PD. These tasks can be performed using a combination of one or two executive function tasks. The current study examined whether persons with PD would demonstrate greater dual task effects on cognition compared to healthy older adults (HOAs) during a concurrent cycling task. Participants with and without PD completed a battery of 12 cognitive tasks assessing visual and verbal processing in the following cognitive domains: speed of processing, controlled processing, working memory and executive function. Persons with PD exhibited impairments compared to healthy participants in select tasks (i.e., 0-Back, 2-Back and operation span). Further, both groups unexpectedly exhibited dual task facilitation of response times in visual tasks across cognitive domains, and improved verbal recall during an executive function task. Only one measure, 2-back, showed a speed-accuracy trade-off in the dual task. These results demonstrate that, when paired with a motor task in which they are not impaired, people with PD exhibit similar dual task effects on cognitive tasks as HOAs, even when these dual task effects are facilitative. More generally, these findings demonstrate that pairing cognitive tasks with cycling may actually improve cognitive performance which may have therapeutic relevance to cognitive decline associated with aging and PD pathology. PMID:28088064

  5. Using GOMS and Bayesian plan recognition to develop recognition models of operator behavior

    NASA Astrophysics Data System (ADS)

    Zaientz, Jack D.; DeKoven, Elyon; Piegdon, Nicholas; Wood, Scott D.; Huber, Marcus J.

    2006-05-01

    Trends in combat technology research point to an increasing role for uninhabited vehicles in modern warfare tactics. To support increased span of control over these vehicles human responsibilities need to be transformed from tedious, error-prone and cognition intensive operations into tasks that are more supervisory and manageable, even under intensely stressful conditions. The goal is to move away from only supporting human command of low-level system functions to intention-level human-system dialogue about the operator's tasks and situation. A critical element of this process is developing the means to identify when human operators need automated assistance and to identify what assistance they need. Toward this goal, we are developing an unmanned vehicle operator task recognition system that combines work in human behavior modeling and Bayesian plan recognition. Traditionally, human behavior models have been considered generative, meaning they describe all possible valid behaviors. Basing behavior recognition on models designed for behavior generation can offers advantages in improved model fidelity and reuse. It is not clear, however, how to reconcile the structural differences between behavior recognition and behavior modeling approaches. Our current work demonstrates that by pairing a cognitive psychology derived human behavior modeling approach, GOMS, with a Bayesian plan recognition engine, ASPRN, we can translate a behavior generation model into a recognition model. We will discuss the implications for using human performance models in this manner as well as suggest how this kind of modeling may be used to support the real-time control of multiple, uninhabited battlefield vehicles and other semi-autonomous systems.

  6. Working Memory Costs of Task Switching

    ERIC Educational Resources Information Center

    Liefooghe, Baptist; Barrouillet, Pierre; Vandierendonck, Andre; Camos, Valerie

    2008-01-01

    Although many accounts of task switching emphasize the importance of working memory as a substantial source of the switch cost, there is a lack of evidence demonstrating that task switching actually places additional demands on working memory. The present study addressed this issue by implementing task switching in continuous complex span tasks…

  7. 76 FR 23187 - Drawbridge Operation Regulation; New Jersey Intracoastal Waterway (NJICW), Beach Thorofare, NJ

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-04-26

    ... operational integrity. Under this deviation, the bascule lift span of the drawbridge will remain in the closed...: The New Jersey Department of Transportation (NJDOT) owns and operates the bascule-lift span of the... the operator and gate house. Under this deviation, the bascule lift span of the drawbridge will be...

  8. 13. View of swing span showing bridge operator's control cabin, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    13. View of swing span showing bridge operator's control cabin, looking northeast - India Point Railroad Bridge, Spanning Seekonk River between Providence & East Providence, Providence, Providence County, RI

  9. Processing speed and working memory span: their differential role in superficial and deep memory processes in schizophrenia.

    PubMed

    Brébion, Gildas; Bressan, Rodrigo A; Pilowsky, Lyn S; David, Anthony S

    2011-05-01

    Previous work has suggested that decrement in both processing speed and working memory span plays a role in the memory impairment observed in patients with schizophrenia. We undertook a study to examine simultaneously the effect of these two factors. A sample of 49 patients with schizophrenia and 43 healthy controls underwent a battery of verbal and visual memory tasks. Superficial and deep encoding memory measures were tallied. We conducted regression analyses on the various memory measures, using processing speed and working memory span as independent variables. In the patient group, processing speed was a significant predictor of superficial and deep memory measures in verbal and visual memory. Working memory span was an additional significant predictor of the deep memory measures only. Regression analyses involving all participants revealed that the effect of diagnosis on all the deep encoding memory measures was reduced to non-significance when processing speed was entered in the regression. Decreased processing speed is involved in verbal and visual memory deficit in patients, whether the task require superficial or deep encoding. Working memory is involved only insofar as the task requires a certain amount of effort.

  10. Does dual-task coordination performance decline in later life?

    PubMed

    Sebastián, María V; Mediavilla, Roberto

    2017-05-01

    This cross-sectional study examined whether changes occur in people’s capacity to coordinate two simultaneous tasks (dual-task) when transitioning from adulthood to later life. The central executive, Baddeley’s working memory model component, is responsible for this coordination. Contradictory results have been reported regarding the relationship between ageing and dual-task performance; but these seem to be related to methodological issues that have been addressed in this study. Nine hundred and seventy-two participants, aged between 35 and 90 years old, volunteered to carry out a verbal digit span task, followed by single and concurrent (dual-task) tests: first, a box crossing task, then, the digit recall task in relation to their memory span, and finally, both these tests simultaneously. We found no difference in people’s capacity to coordinate their attention when doing two tasks in adulthood or healthy later life, including those in the oldest age groups. Furthermore, gender and educational level were not related to dual-task performance. The results support the normal functioning of the central executive in very old people. These data contrast with research with patients suffering from different types of dementia, which show a decrease in their dual-task performance.

  11. Turning Simple Span into Complex Span: Time for Decay or Interference from Distractors?

    ERIC Educational Resources Information Center

    Lewandowsky, Stephan; Geiger, Sonja M.; Morrell, Daniel B.; Oberauer, Klaus

    2010-01-01

    We investigated the effects of the duration and type of to-be-articulated distractors during encoding of a verbal list into short-term memory (STM). Distractors and to-be-remembered items alternated during list presentation, as in the complex-span task that underlies much of working-memory research. According to an interference model of STM, known…

  12. Human performance across decision making, selective attention, and working memory tasks: Experimental data and computer simulations.

    PubMed

    Stocco, Andrea; Yamasaki, Brianna L; Prat, Chantel S

    2018-04-01

    This article describes the data analyzed in the paper "Individual differences in the Simon effect are underpinned by differences in the competitive dynamics in the basal ganglia: An experimental verification and a computational model" (Stocco et al., 2017) [1]. The data includes behavioral results from participants performing three cognitive tasks (Probabilistic Stimulus Selection (Frank et al., 2004) [2], Simon task (Craft and Simon, 1970) [3], and Automated Operation Span (Unsworth et al., 2005) [4]), as well as simulationed traces generated by a computational neurocognitive model that accounts for individual variations in human performance across the tasks. The experimental data encompasses individual data files (in both preprocessed and native output format) as well as group-level summary files. The simulation data includes the entire model code, the results of a full-grid search of the model's parameter space, and the code used to partition the model space and parallelize the simulations. Finally, the repository includes the R scripts used to carry out the statistical analyses reported in the original paper.

  13. Beyond capacity limitations II: Effects of lexical processes on word recall in verbal working memory tasks in children with and without specific language impairment

    PubMed Central

    Mainela-Arnold, Elina; Evans, Julia L.; Coady, Jeffry

    2010-01-01

    Purpose This study investigated the impact of lexical processes on target word recall in sentence span tasks in children with and without specific language impairment (SLI). Method Participants were 42 children (ages 8;2–12;3), 21 with SLI and 21 typically developing peers matched on age and nonverbal IQ. Children completed a sentence span task where target words to be recalled varied in word frequency and neighborhood density. Two measures of lexical processes were examined, the number of non-target competitor words activated during a gating task (lexical cohort competition) and word definitions. Results Neighborhood density had no effect on word recall for either group. However, both groups recalled significantly more high than low frequency words. Lexical cohort competition and specificity of semantic representations accounted for unique variance in the number of target word recalled in the SLI and CA groups combined. Conclusions Performance on verbal working memory span tasks for both SLI and CA children is influenced by word frequency, lexical cohorts, and semantic representations. Future studies need to examine the extent to which verbal working memory capacity is a cognitive construct independent of extant language knowledge representations. PMID:20705747

  14. Cross-linguistic interactions influence reading development in bilinguals: a comparison between early balanced French-Basque and Spanish-Basque bilingual children.

    PubMed

    Lallier, Marie; Acha, Joana; Carreiras, Manuel

    2016-01-01

    This study investigates whether orthographic consistency and transparency of languages have an impact on the development of reading strategies and reading sub-skills (i.e. phonemic awareness and visual attention span) in bilingual children. We evaluated 21 French (opaque)-Basque (transparent) bilingual children and 21 Spanish (transparent)-Basque (transparent) bilingual children at Grade 2, and 16 additional children of each group at Grade 5. All of them were assessed in their common language (i.e. Basque) on tasks measuring word and pseudoword reading, phonemic awareness and visual attention span skills. The Spanish speaking groups showed better Basque pseudoword reading and better phonemic awareness abilities than their French speaking peers, but only in the most difficult conditions of the tasks. However, on the visual attention span task, the French-Basque bilinguals showed the most efficient visual processing strategies to perform the task. Therefore, learning to read in an additional language affected differently Basque literacy skills, depending on whether this additional orthography was opaque (e.g. French) or transparent (e.g. Spanish). Moreover, we showed that the most noteworthy effects of Spanish and French orthographic transparency on Basque performance were related to the size of the phonological and visual grain used to perform the tasks. © 2015 John Wiley & Sons Ltd.

  15. National facilities study. Volume 3: Mission and requirements model report

    NASA Technical Reports Server (NTRS)

    1994-01-01

    The National Facility Study (NFS) was initiated in 1992 by Daniel S. Goldin, Administrator of NASA as an initiative to develop a comprehensive and integrated long-term plan for future facilities. The resulting, multi-agency NFS consisted of three Task Groups: Aeronautics, Space Operations, and Space Research and Development (R&D) Task Groups. A fourth group, the Engineering and Cost Analysis Task Group, was subsequently added to provide cross-cutting functions, such as assuring consistency in developing an inventory of space facilities. Space facilities decisions require an assessment of current and future needs. Therefore, the two task groups dealing with space developed a consistent model of future space mission programs, operations and R&D. The model is a middle ground baseline constructed for NFS analytical purposes with excursions to cover potential space program strategies. The model includes three major sectors: DOD, civilian government, and commercial space. The model spans the next 30 years because of the long lead times associated with facilities development and usage. This document, Volume 3 of the final NFS report, is organized along the following lines: Executive Summary -- provides a summary view of the 30-year mission forecast and requirements baseline, an overview of excursions from that baseline that were studied, and organization of the report; Introduction -- provides discussions of the methodology used in this analysis; Baseline Model -- provides the mission and requirements model baseline developed for Space Operations and Space R&D analyses; Excursions from the baseline -- reviews the details of variations or 'excursions' that were developed to test the future program projections captured in the baseline; and a Glossary of Acronyms.

  16. Short-term memory, executive control, and children's route learning.

    PubMed

    Purser, Harry R M; Farran, Emily K; Courbois, Yannick; Lemahieu, Axelle; Mellier, Daniel; Sockeel, Pascal; Blades, Mark

    2012-10-01

    The aim of this study was to investigate route-learning ability in 67 children aged 5 to 11years and to relate route-learning performance to the components of Baddeley's model of working memory. Children carried out tasks that included measures of verbal and visuospatial short-term memory and executive control and also measures of verbal and visuospatial long-term memory; the route-learning task was conducted using a maze in a virtual environment. In contrast to previous research, correlations were found between both visuospatial and verbal memory tasks-the Corsi task, short-term pattern span, digit span, and visuospatial long-term memory-and route-learning performance. However, further analyses indicated that these relationships were mediated by executive control demands that were common to the tasks, with long-term memory explaining additional unique variance in route learning. Copyright © 2012 Elsevier Inc. All rights reserved.

  17. Noninvasive Electroencephalogram Based Control of a Robotic Arm for Reach and Grasp Tasks

    NASA Astrophysics Data System (ADS)

    Meng, Jianjun; Zhang, Shuying; Bekyo, Angeliki; Olsoe, Jaron; Baxter, Bryan; He, Bin

    2016-12-01

    Brain-computer interface (BCI) technologies aim to provide a bridge between the human brain and external devices. Prior research using non-invasive BCI to control virtual objects, such as computer cursors and virtual helicopters, and real-world objects, such as wheelchairs and quadcopters, has demonstrated the promise of BCI technologies. However, controlling a robotic arm to complete reach-and-grasp tasks efficiently using non-invasive BCI has yet to be shown. In this study, we found that a group of 13 human subjects could willingly modulate brain activity to control a robotic arm with high accuracy for performing tasks requiring multiple degrees of freedom by combination of two sequential low dimensional controls. Subjects were able to effectively control reaching of the robotic arm through modulation of their brain rhythms within the span of only a few training sessions and maintained the ability to control the robotic arm over multiple months. Our results demonstrate the viability of human operation of prosthetic limbs using non-invasive BCI technology.

  18. The generality of working memory capacity: a latent-variable approach to verbal and visuospatial memory span and reasoning.

    PubMed

    Kane, Michael J; Hambrick, David Z; Tuholski, Stephen W; Wilhelm, Oliver; Payne, Tabitha W; Engle, Randall W

    2004-06-01

    A latent-variable study examined whether verbal and visuospatial working memory (WM) capacity measures reflect a primarily domain-general construct by testing 236 participants in 3 span tests each of verbal WM. visuospatial WM, verbal short-term memory (STM), and visuospatial STM. as well as in tests of verbal and spatial reasoning and general fluid intelligence (Gf). Confirmatory' factor analyses and structural equation models indicated that the WM tasks largely reflected a domain-general factor, whereas STM tasks, based on the same stimuli as the WM tasks, were much more domain specific. The WM construct was a strong predictor of Gf and a weaker predictor of domain-specific reasoning, and the reverse was true for the STM construct. The findings support a domain-general view of WM capacity, in which executive-attention processes drive the broad predictive utility of WM span measures, and domain-specific storage and rehearsal processes relate more strongly to domain-specific aspects of complex cognition. ((c) 2004 APA, all rights reserved)

  19. The scope and control of attention as separate aspects of working memory.

    PubMed

    Shipstead, Zach; Redick, Thomas S; Hicks, Kenny L; Engle, Randall W

    2012-01-01

    The present study examines two varieties of working memory (WM) capacity task: visual arrays (i.e., a measure of the amount of information that can be maintained in working memory) and complex span (i.e., a task that taps WM-related attentional control). Using previously collected data sets we employ confirmatory factor analysis to demonstrate that visual arrays and complex span tasks load on separate, but correlated, factors. A subsequent series of structural equation models and regression analyses demonstrate that these factors contribute both common and unique variance to the prediction of general fluid intelligence (Gf). However, while visual arrays does contribute uniquely to higher cognition, its overall correlation to Gf is largely mediated by variance associated with the complex span factor. Thus we argue that visual arrays performance is not strictly driven by a limited-capacity storage system (e.g., the focus of attention; Cowan, 2001), but may also rely on control processes such as selective attention and controlled memory search.

  20. 76 FR 26606 - Drawbridge Operation Regulation; Neches River, Beaumont, TX

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-05-09

    ... deviation from the regulation governing the operation of the KCS vertical lift span bridge across the Neches... Southern Railroad has requested a temporary deviation from the operating schedule of the vertical lift span... in the open-to-navigation position. In accordance with 33 CFR 117.971, the vertical lift span of the...

  1. The Relations between Television Exposure and Executive Function in Chinese Preschoolers: The Moderated Role of Parental Mediation Behaviors

    PubMed Central

    Yang, Xiaohui; Chen, Zhe; Wang, Zhenhong; Zhu, Liqi

    2017-01-01

    The present study examined the relations between preschoolers’ television exposure and executive functions (EF). One hundred and nineteen 3- to 6-year-old children and their parents participated. Parents filled in a questionnaire regarding children’s television viewing time, television content and parental mediation behaviors about their child’s television viewing. The children were asked to finish six EF tasks, including the backward digit span task, the spatial span task, the boy–girl Stroop, the Simon task, the flanker task and the Tower of Hanoi task that assessed working memory, inhibition and planning, respectively. Children’s vocabulary was tested using Peabody Picture Vocabulary Test, and included as control variables in addition to socioeconomic status of the participated families. The results showed that television viewing time and child-directed educational programs were positively associated with EF. In addition, television content fully mediated the effect of television viewing time on EF and parental restrictive approach strategies moderated the effect of television viewing time on EF. PMID:29089912

  2. Interference, aging, and visuospatial working memory: the role of similarity.

    PubMed

    Rowe, Gillian; Hasher, Lynn; Turcotte, Josée

    2010-11-01

    Older adults' performance on working memory (WM) span tasks is known to be negatively affected by the buildup of proactive interference (PI) across trials. PI has been reduced in verbal tasks and performance increased by presenting distinctive items across trials. In addition, reversing the order of trial presentation (i.e., starting with the longest sets first) has been shown to reduce PI in both verbal and visuospatial WM span tasks. We considered whether making each trial visually distinct would improve older adults' visuospatial WM performance, and whether combining the 2 PI-reducing manipulations, distinct trials and reversed order of presentation, would prove additive, thus providing even greater benefit. Forty-eight healthy older adults (age range = 60-77 years) completed 1 of 3 versions of a computerized Corsi block test. For 2 versions of the task, trials were either all visually similar or all visually distinct, and were presented in the standard ascending format (shortest set size first). In the third version, visually distinct trials were presented in a reverse order of presentation (longest set size first). Span scores were reliably higher in the ascending version for visually distinct compared with visually similar trials, F(1, 30) = 4.96, p = .03, η² = .14. However, combining distinct trials and a descending format proved no more beneficial than administering the descending format alone. Our findings suggest that a more accurate measurement of the visuospatial WM span scores of older adults (and possibly neuropsychological patients) might be obtained by reducing within-test interference.

  3. Front-line managers as boundary spanners: effects of span and time on nurse supervision satisfaction.

    PubMed

    Meyer, Raquel M; O'Brien-Pallas, Linda; Doran, Diane; Streiner, David; Ferguson-Paré, Mary; Duffield, Christine

    2011-07-01

    To examine the influence of nurse manager span (number of direct report staff), time in staff contact, transformational leadership practices and operational hours on nurse supervision satisfaction. Increasing role complexity has intensified the boundary spanning functions of managers. Because work demands and scope vary by management position, time in staff contact rather than span may better explain managers' capacity to support staff. A descriptive, correlational design was used to collect cross-sectional survey and prospective work log and administrative data from a convenience sample of 558 nurses in 51 clinical areas and 31 front-line nurse managers from four acute care hospitals in 2007-2008. Data were analysed using hierarchical linear modelling. Span, but not time in staff contact, interacted with leadership and operational hours to explain supervision satisfaction. With compressed operational hours, supervision satisfaction was lower with highly transformational leadership in combination with wider spans. With extended operational hours, supervision satisfaction was higher with highly transformational leadership, and this effect was more pronounced under wider spans. Operational hours, which influence the manager's daily span (average number of direct report staff working per weekday), should be factored into the design of front-line management positions. © 2011 The Authors. Journal compilation © 2011 Blackwell Publishing Ltd.

  4. From Children to Adults: Motor Performance across the Life-Span

    PubMed Central

    Leversen, Jonas S. R.; Haga, Monika; Sigmundsson, Hermundur

    2012-01-01

    The life-span approach to development provides a theoretical framework to examine the general principles of life-long development. This study aims to investigate motor performance across the life span. It also aims to investigate if the correlations between motor tasks increase with aging. A cross-sectional design was used to describe the effects of aging on motor performance across age groups representing individuals from childhood to young adult to old age. Five different motor tasks were used to study changes in motor performance within 338 participants (7–79 yrs). Results showed that motor performance increases from childhood (7–9) to young adulthood (19–25) and decreases from young adulthood (19–25) to old age (66–80). These results are mirroring results from cognitive research. Correlation increased with increasing age between two fine motor tasks and two gross motor tasks. We suggest that the findings might be explained, in part, by the structural changes that have been reported to occur in the developing and aging brain and that the theory of Neural Darwinism can be used as a framework to explain why these changes occur. PMID:22719958

  5. Does Controlling for Temporal Parameters Change the Levels-of-Processing Effect in Working Memory?

    PubMed Central

    Loaiza, Vanessa M.; Camos, Valérie

    2016-01-01

    The distinguishability between working memory (WM) and long-term memory has been a frequent and long-lasting source of debate in the literature. One recent method of identifying the relationship between the two systems has been to consider the influence of long-term memory effects, such as the levels-of-processing (LoP) effect, in WM. However, the few studies that have examined the LoP effect in WM have shown divergent results. This study examined the LoP effect in WM by considering a theoretically meaningful methodological aspect of the LoP span task. Specifically, we fixed the presentation duration of the processing component a priori because such fixed complex span tasks have shown differences when compared to unfixed tasks in terms of recall from WM as well as the latent structure of WM. After establishing a fixed presentation rate from a pilot study, the LoP span task presented memoranda in red or blue font that were immediately followed by two processing words that matched the memoranda in terms of font color or semantic relatedness. On presentation of the processing words, participants made deep or shallow processing decisions for each of the memoranda before a cue to recall them from WM. Participants also completed delayed recall of the memoranda. Results indicated that LoP affected delayed recall, but not immediate recall from WM. These results suggest that fixing temporal parameters of the LoP span task does not moderate the null LoP effect in WM, and further indicate that WM and long-term episodic memory are dissociable on the basis of LoP effects. PMID:27152126

  6. Does Controlling for Temporal Parameters Change the Levels-of-Processing Effect in Working Memory?

    PubMed

    Loaiza, Vanessa M; Camos, Valérie

    2016-01-01

    The distinguishability between working memory (WM) and long-term memory has been a frequent and long-lasting source of debate in the literature. One recent method of identifying the relationship between the two systems has been to consider the influence of long-term memory effects, such as the levels-of-processing (LoP) effect, in WM. However, the few studies that have examined the LoP effect in WM have shown divergent results. This study examined the LoP effect in WM by considering a theoretically meaningful methodological aspect of the LoP span task. Specifically, we fixed the presentation duration of the processing component a priori because such fixed complex span tasks have shown differences when compared to unfixed tasks in terms of recall from WM as well as the latent structure of WM. After establishing a fixed presentation rate from a pilot study, the LoP span task presented memoranda in red or blue font that were immediately followed by two processing words that matched the memoranda in terms of font color or semantic relatedness. On presentation of the processing words, participants made deep or shallow processing decisions for each of the memoranda before a cue to recall them from WM. Participants also completed delayed recall of the memoranda. Results indicated that LoP affected delayed recall, but not immediate recall from WM. These results suggest that fixing temporal parameters of the LoP span task does not moderate the null LoP effect in WM, and further indicate that WM and long-term episodic memory are dissociable on the basis of LoP effects.

  7. The Influence of Levels of Processing on Recall from Working Memory and Delayed Recall Tasks

    ERIC Educational Resources Information Center

    Loaiza, Vanessa M.; McCabe, David P.; Youngblood, Jessie L.; Rose, Nathan S.; Myerson, Joel

    2011-01-01

    Recent research in working memory has highlighted the similarities involved in retrieval from complex span tasks and episodic memory tasks, suggesting that these tasks are influenced by similar memory processes. In the present article, the authors manipulated the level of processing engaged when studying to-be-remembered words during a reading…

  8. Measuring Working Memory With Digit Span and the Letter-Number Sequencing Subtests From the WAIS-IV: Too Low Manipulation Load and Risk for Underestimating Modality Effects.

    PubMed

    Egeland, Jens

    2015-01-01

    The Wechsler Adult Intelligence Scale (WAIS) is one of the most frequently used tests among psychologists. In the fourth edition of the test (WAIS-IV), the subtests Digit Span and Letter-Number Sequencing are expanded for better measurement of working memory (WM). However, it is not clear whether the new extended tasks contribute sufficient complexity to be sensitive measures of manipulation WM, nor do we know to what degree WM capacity differs between the visual and the auditory modality because the WAIS-IV only tests the auditory modality. Performance by a mixed sample of 226 patients referred for neuropsychological examination on the Digit Span and Letter-Number Sequencing subtests from the WAIS-IV and on Spatial Span from the Wechsler Memory Scale-Third Edition was analyzed in two confirmatory factor analyses to investigate whether a unitary WM model or divisions based on modality or level/complexity best fit the data. The modality model showed the best fit when analyzing summed scores for each task as well as scores for the longest span. The clinician is advised to apply tests with higher manipulation load and to consider testing visual span as well before drawing conclusions about impaired WM from the WAIS-IV.

  9. Covert retrieval in working memory impacts the phenomenological characteristics remembered during episodic memory.

    PubMed

    Loaiza, Vanessa M; Borovanska, Borislava M

    2018-01-01

    Much research has investigated the qualitative experience of retrieving events from episodic memory (EM). The present study investigated whether covert retrieval in WM increases the phenomenological characteristics that participants find memorable in EM using tasks that distract attention from the maintenance of memoranda (i.e., complex span; Experiment 1) relative to tasks that do not (i.e., short or long list lengths of simple span; Experiments 1 and 2). Participants rated the quality of the phonological, semantic, and temporal-contextual characteristics remembered during a delayed memory characteristics questionnaire (MCQ). Whereas an advantage of the complex over simple span items was observed for each characteristic (Experiment 1), no such difference was observed between short and long trials of simple span (Experiment 2). These results are consistent with the view that covert retrieval in WM promotes content-context bindings that are later accessible from EM for both objective performance and subjective details of the remembered information. Copyright © 2017 Elsevier Inc. All rights reserved.

  10. 75 FR 45477 - Drawbridge Operation Regulation; Company Canal, Bourg, LA

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-03

    ... deviation from the regulation governing the operation of the LA 24 vertical lift span bridge across Company... from the operating schedule of the vertical lift span bridge across Company Canal at mile 8.1 in Bourg...), the vertical lift span of the bridge currently opens on signal except that, from 10 p.m. to 6 a.m. the...

  11. Short-term and long-term memory in early temporal lobe dysfunction.

    PubMed

    Hershey, T; Craft, S; Glauser, T A; Hale, S

    1998-01-01

    Following medial temporal damage, mature humans are impaired in retaining new information over long delays but not short delays. The question of whether a similar dissociation occurs in children was addressed by testing children (ages 7-16) with unilateral temporal lobe epilepsy (TLE) and controls on short- and long-term memory tasks, including a spatial delayed response task (SDR). Early-onset TLE did not affect performance on short delays on SDR, but it did impair performance at the longest delay (60 s), similar to adults with unilateral medial temporal damage. In addition, early-onset TLE affected performance on pattern recall, spatial span, and verbal span with rehearsal interference. No differences were found on story recall or on a response inhibition task.

  12. A Holistic Model for Wellness and Prevention over the Life Span.

    ERIC Educational Resources Information Center

    Witmer, J. Melvin; Sweeney, Thomas J.

    1992-01-01

    Presents integrated paradigm for wellness and prevention over the life span for purpose of theory building, research, clinical application, education, advocacy, and consciousness raising. Model described includes 11 characteristics desirable for optimal health and functioning. Notes characteristics are expressed through five life tasks of…

  13. Spatial versus verbal memory impairments in patients with fibromyalgia.

    PubMed

    Kim, Seong-Ho; Kim, Sang-Hyon; Kim, Seong-Kyu; Nam, Eun Jung; Han, Seung Woo; Lee, Seung Jae

    2012-05-01

    Mounting evidence suggests that individuals with fibromyalgia (FM) have impairments in general cognitive functions. However, few studies have explored the possibility of dissociation between verbal and visuospatial memory impairments in FM. Therefore, the purpose of this study was to investigate the asymmetrical impairment of cognitive functions between verbal and visuospatial memory and between short-term and long-term memory. Neuropsychological assessments were carried out on 23 female patients with FM and 24 healthy female controls. Verbal memory abilities were assessed using the Korean version of the Rey auditory verbal learning test (KAVLT) and digit span task, and visuospatial memory abilities were assessed using the Korean version of the Rey complex figure test (KCFT) and spatial span task. The analysis of covariance was used to assess group differences in performance on cognitive tests after controlling for depression. The two groups did not significantly differ in terms of age, years of education, or in their estimated verbal and performance IQ, but FM patients reported more severe depressive symptoms than did controls on the Beck depression inventory. Significant group differences were found in immediate and delayed recall on the KCFT (F (1,44) = 6.49, p = 0.014 and F (1,44) = 6.96, p = 0.011, respectively), whereas no difference was found in immediate and delayed recall on the KAVLT. In terms of short-term memory, neither the digit span task nor spatial span task showed any difference between groups, regardless of whether repetition was forward or backward. These findings suggest that spatial memory abilities may be more impaired than verbal memory abilities in patients with FM.

  14. Interactions of cognitive and auditory abilities in congenitally blind individuals.

    PubMed

    Rokem, Ariel; Ahissar, Merav

    2009-02-01

    Congenitally blind individuals have been found to show superior performance in perceptual and memory tasks. In the present study, we asked whether superior stimulus encoding could account for performance in memory tasks. We characterized the performance of a group of congenitally blind individuals on a series of auditory, memory and executive cognitive tasks and compared their performance to that of sighted controls matched for age, education and musical training. As expected, we found superior verbal spans among congenitally blind individuals. Moreover, we found superior speech perception, measured by resilience to noise, and superior auditory frequency discrimination. However, when memory span was measured under conditions of equivalent speech perception, by adjusting the signal to noise ratio for each individual to the same level of perceptual difficulty (80% correct), the advantage in memory span was completely eliminated. Moreover, blind individuals did not possess any advantage in cognitive executive functions, such as manipulation of items in memory and math abilities. We propose that the short-term memory advantage of blind individuals results from better stimulus encoding, rather than from superiority at subsequent processing stages.

  15. Commentary: Working memory training and ADHD - where does its potential lie? Reflections on Chacko et al. (2014).

    PubMed

    Gathercole, Susan E

    2014-03-01

    Chacko et al.'s investigation of the clinical utility of WM training to alleviate key symptoms of ADHD is timely and substantial, and marks a significant point in cognitive training research. Cogmed Working Memory Training (CWMT) involves intensive practice on multiple memory span tasks that increase in difficulty as performance improves with practice. Relative to a placebo version in which the span level of the memory tasks are kept at a low fixed level, Chacko et al. () found that CWMT boosted the performance of children with ADHD on short-term memory (STM) tasks similar to trained activities. Complex WM span measures sharing little overlap with the structure of training activities were not enhanced. Neither did active CWMT ameliorate classic symptoms of ADHD such as parent or teacher ratings of attentional problems, or direct measures of motor impulsivity and sustained attention. Reading, spelling, comprehension or mathematics scores similarly showed no response to training. © 2014 The Authors. Journal of Child Psychology and Psychiatry. © 2014 Association for Child and Adolescent Mental Health.

  16. Age trends for failures of sustained attention.

    PubMed

    Carriere, Jonathan S A; Cheyne, J Allan; Solman, Grayden J F; Smilek, Daniel

    2010-09-01

    Recent research has revealed an age-related reduction in errors in a sustained attention task, suggesting that sustained attention abilities improve with age. Such results seem paradoxical in light of the well-documented age-related declines in cognitive performance. In the present study, performance on the sustained attention to response task (SART) was assessed in a supplemented archival sample of 638 individuals between 14 and 77 years old. SART errors and response speed appeared to decline in a linear fashion as a function of age throughout the age span studied. In contrast, other measures of sustained attention (reaction time coefficient of variation), anticipation, and omissions) showed a decrease early in life and then remained unchanged for the rest of the life span. Thus, sustained attention shows improvements with maturation in early adulthood but then does not change with aging in older adults. On the other hand, aging across the entire life span leads to a more strategic (i.e., slower) response style that reduces the overt and critical consequences (i.e., SART errors) of momentary task disengagement. (c) 2010 APA, all rights reserved.

  17. No Evidence for Temporal Decay in Working Memory

    ERIC Educational Resources Information Center

    Lewandowsky, Stephan; Oberauer, Klaus

    2009-01-01

    What drives forgetting in working memory? Recent evidence suggests that in a complex-span task in which an irrelevant processing task alternates with presentation of the memoranda, recall declines when the time taken to complete the processing task is extended while holding the time for rehearsal in between processing steps constant (Portrat,…

  18. Superior parietal lobule dysfunction in a homogeneous group of dyslexic children with a visual attention span disorder.

    PubMed

    Peyrin, C; Démonet, J F; N'Guyen-Morel, M A; Le Bas, J F; Valdois, S

    2011-09-01

    A visual attention (VA) span disorder has been reported in dyslexic children as potentially responsible for their poor reading outcome. The purpose of the current paper was to identify the cerebral correlates of this VA span disorder. For this purpose, 12 French dyslexic children with severe reading and VA span disorders and 12 age-matched control children were engaged in a categorisation task under fMRI. Two flanked and isolated conditions were designed which both involved multiple-element simultaneous visual processing but taxed visual attention differently. For skilled readers, flanked stimuli processing activated a large bilateral cortical network comprising the superior and inferior parietal cortex, the inferior temporal cortex, the striate and extrastriate visual cortex, the middle frontal cortex and the anterior cingulate cortex while the less attention-demanding task of isolated stimuli only activated the inferior occipito-temporal cortex bilaterally. With respect to controls, the dyslexic children showed significantly reduced activation within bilateral parietal and temporal areas during flanked processing, but no difference during the isolated condition. The neural correlates of the processes involved in attention-demanding multi-element processing tasks were more specifically addressed by contrasting the flanked and the isolated conditions. This contrast elicited activation of the left precuneus/superior parietal lobule in the controls, but not in the dyslexic children. These findings provide new insights on the role of parietal regions, in particular the left superior parietal lobule, in the visual attention span and in developmental dyslexia. Copyright © 2010 Elsevier Inc. All rights reserved.

  19. Rate of Visual Information Pick-Up in Learning Disabled and Normal Boys.

    ERIC Educational Resources Information Center

    Bryant, Susan K.; And Others

    1983-01-01

    A span-of-apprehension task and a backward masking technique were combined to allow measurement of the apprehension span of a sample of 34 learning disabled and normal boys about 8 to 13 years old at various time intervals following stimulus presentation. (Author/SW)

  20. Increased distractibility in schizotypy: Independent of individual differences in working memory capacity?

    PubMed

    Marsh, John E; Vachon, François; Sörqvist, Patrik

    2017-03-01

    Individuals with schizophrenia typically show increased levels of distractibility. This has been attributed to impaired working memory capacity (WMC), since lower WMC is typically associated with higher distractibility, and schizophrenia is typically associated with impoverished WMC. Here, participants performed verbal and spatial serial recall tasks that were accompanied by to-be-ignored speech tokens. For the few trials wherein one speech token was replaced with a different token, impairment was produced to task scores (a deviation effect). Participants subsequently completed a schizotypy questionnaire and a WMC measure. Higher schizotypy scores were associated with lower WMC (as measured with operation span, OSPAN), but WMC and schizotypy scores explained unique variance in relation to the mean magnitude of the deviation effect. These results suggest that schizotypy is associated with heightened domain-general distractibility, but that this is independent of its relationship with WMC.

  1. A theoretical framework for negotiating the path of emergency management multi-agency coordination.

    PubMed

    Curnin, Steven; Owen, Christine; Paton, Douglas; Brooks, Benjamin

    2015-03-01

    Multi-agency coordination represents a significant challenge in emergency management. The need for liaison officers working in strategic level emergency operations centres to play organizational boundary spanning roles within multi-agency coordination arrangements that are enacted in complex and dynamic emergency response scenarios creates significant research and practical challenges. The aim of the paper is to address a gap in the literature regarding the concept of multi-agency coordination from a human-environment interaction perspective. We present a theoretical framework for facilitating multi-agency coordination in emergency management that is grounded in human factors and ergonomics using the methodology of core-task analysis. As a result we believe the framework will enable liaison officers to cope more efficiently within the work domain. In addition, we provide suggestions for extending the theory of core-task analysis to an alternate high reliability environment. Copyright © 2014 Elsevier Ltd and The Ergonomics Society. All rights reserved.

  2. Aging of theory of mind: the influence of educational level and cognitive processing.

    PubMed

    Li, Xiaoming; Wang, Kai; Wang, Fan; Tao, Qian; Xie, Yu; Cheng, Qi

    2013-01-01

    Previous studies of theory of mind (ToM) in old age have provided mixed results. We predicted that educational level and cognitive processing are two factors influencing the pattern of the aging of ToM. To test this hypothesis, a younger group who received higher education (mean age 20.46 years), an older group with an education level equal to that of the young group (mean age 76.29 years), and an older group with less education (mean age 73.52 years) were recruited. ToM tasks included the following tests: the second-order false-belief task, the faux-pas task, the eyes test, and tests of fundamental aspects of cognitive function that included two background tests (memory span and processing speed) and three subcomponents of executive function (inhibition, updating, and shifting). We found that the younger group and the older group with equally high education outperformed the older group with less education in false-belief and faux-pas tasks. However, there was no significant difference between the two former groups. The three groups of participants performed equivalently in the eyes test as well as in control tasks (false-belief control question, faux-pas control question, faux-pas control story, and Eyes Test control task). The younger group outperformed the other two groups in the cognitive processing tasks. Mediation analyses showed that difficulties in inhibition, memory span, and processing speed mediated the age differences in false-belief reasoning. Also, the variables of inhibition, updating, memory span, and processing speed mediated age-related variance in faux-pas. Discussion focused on the links between ToM aging, educational level, and cognitive processing. Supported by Chinese National Natural Science Foundation (number: 30870766) and Anhui Province Natural Science Foundation (number: 11040606M166).

  3. Monitoring the capacity of working memory: Executive control and effects of listening effort

    PubMed Central

    Amichetti, Nicole M.; Stanley, Raymond S.; White, Alison G.

    2013-01-01

    In two experiments, we used an interruption-and-recall (IAR) task to explore listeners’ ability to monitor the capacity of working memory as new information arrived in real time. In this task, listeners heard recorded word lists with instructions to interrupt the input at the maximum point that would still allow for perfect recall. Experiment 1 demonstrated that the most commonly selected segment size closely matched participants’ memory span, as measured in a baseline span test. Experiment 2 showed that reducing the sound level of presented word lists to a suprathreshold but effortful listening level disrupted the accuracy of matching selected segment sizes with participants’ memory spans. The results are discussed in terms of whether online capacity monitoring may be subsumed under other, already enumerated working memory executive functions (inhibition, set shifting, and memory updating). PMID:23400826

  4. Long-Term Episodic Memory in Children with Attention-Deficit/Hyperactivity Disorder

    ERIC Educational Resources Information Center

    Skowronek, Jeffrey S.; Leichtman, Michelle D.; Pillemer, David B.

    2008-01-01

    Twenty-nine grade-matched 4th-8th-grade males, 12 with attention-deficit/hyperactivity disorder (ADHD) (age M = 12.2 years, SD = 1.48), and 17 without (age M = 11.5, SD = 1.59), completed two working memory tasks (digit span and the Simon game) and three long-term episodic memory tasks (a personal event memory task, story memory task, and picture…

  5. 25. VIEW EAST IN BRIDGE TENDER'S HOUSE, (left) ORIGINAL LEVERS ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    25. VIEW EAST IN BRIDGE TENDER'S HOUSE, (left) ORIGINAL LEVERS FOR GASOLINE ENGINE OPERATION OF SWING-SPAN, (right) PANEL F ELECTRIC OPERATION OF GATES AND SWING-SPAN; new bridge located in background - Tipers Bridge, Spanning Great Wicomico River at State Route 200, Kilmarnock, Lancaster County, VA

  6. 40 CFR 63.11224 - What are my monitoring, installation, operation, and maintenance requirements?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... assurance or control activities (including, as applicable, calibration checks and required zero and span... applicable, calibration checks and required zero and span adjustments) do not constitute monitoring... required zero and span adjustments), you must conduct all monitoring in continuous operation at all times...

  7. 40 CFR 63.11224 - What are my monitoring, installation, operation, and maintenance requirements?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... assurance or control activities (including, as applicable, calibration checks and required zero and span... applicable, calibration checks and required zero and span adjustments) do not constitute monitoring... required zero and span adjustments), you must conduct all monitoring in continuous operation at all times...

  8. Generalization of Auditory Sensory and Cognitive Learning in Typically Developing Children.

    PubMed

    Murphy, Cristina F B; Moore, David R; Schochat, Eliane

    2015-01-01

    Despite the well-established involvement of both sensory ("bottom-up") and cognitive ("top-down") processes in literacy, the extent to which auditory or cognitive (memory or attention) learning transfers to phonological and reading skills remains unclear. Most research has demonstrated learning of the trained task or even learning transfer to a closely related task. However, few studies have reported "far-transfer" to a different domain, such as the improvement of phonological and reading skills following auditory or cognitive training. This study assessed the effectiveness of auditory, memory or attention training on far-transfer measures involving phonological and reading skills in typically developing children. Mid-transfer was also assessed through untrained auditory, attention and memory tasks. Sixty 5- to 8-year-old children with normal hearing were quasi-randomly assigned to one of five training groups: attention group (AG), memory group (MG), auditory sensory group (SG), placebo group (PG; drawing, painting), and a control, untrained group (CG). Compliance, mid-transfer and far-transfer measures were evaluated before and after training. All trained groups received 12 x 45-min training sessions over 12 weeks. The CG did not receive any intervention. All trained groups, especially older children, exhibited significant learning of the trained task. On pre- to post-training measures (test-retest), most groups exhibited improvements on most tasks. There was significant mid-transfer for a visual digit span task, with highest span in the MG, relative to other groups. These results show that both sensory and cognitive (memory or attention) training can lead to learning in the trained task and to mid-transfer learning on a task (visual digit span) within the same domain as the trained tasks. However, learning did not transfer to measures of language (reading and phonological awareness), as the PG and CG improved as much as the other trained groups. Further research is required to investigate the effects of various stimuli and lengths of training on the generalization of sensory and cognitive learning to literacy skills.

  9. Applicability of the Compensatory Encoding Model in Foreign Language Reading: An Investigation with Chinese College English Language Learners

    PubMed Central

    Han, Feifei

    2017-01-01

    While some first language (L1) reading models suggest that inefficient word recognition and small working memory tend to inhibit higher-level comprehension processes; the Compensatory Encoding Model maintains that slow word recognition and small working memory do not normally hinder reading comprehension, as readers are able to operate metacognitive strategies to compensate for inefficient word recognition and working memory limitation as long as readers process a reading task without time constraint. Although empirical evidence is accumulated for support of the Compensatory Encoding Model in L1 reading, there is lack of research for testing of the Compensatory Encoding Model in foreign language (FL) reading. This research empirically tested the Compensatory Encoding Model in English reading among Chinese college English language learners (ELLs). Two studies were conducted. Study one focused on testing whether reading condition varying time affects the relationship between word recognition, working memory, and reading comprehension. Students were tested on a computerized English word recognition test, a computerized Operation Span task, and reading comprehension in time constraint and non-time constraint reading. The correlation and regression analyses showed that the strength of association was much stronger between word recognition, working memory, and reading comprehension in time constraint than that in non-time constraint reading condition. Study two examined whether FL readers were able to operate metacognitive reading strategies as a compensatory way of reading comprehension for inefficient word recognition and working memory limitation in non-time constraint reading. The participants were tested on the same computerized English word recognition test and Operation Span test. They were required to think aloud while reading and to complete the comprehension questions. The think-aloud protocols were coded for concurrent use of reading strategies, classified into language-oriented strategies, content-oriented strategies, re-reading, pausing, and meta-comment. The correlation analyses showed that while word recognition and working memory were only significantly related to frequency of language-oriented strategies, re-reading, and pausing, but not with reading comprehension. Jointly viewed, the results of the two studies, complimenting each other, supported the applicability of the Compensatory Encoding Model in FL reading with Chinese college ELLs. PMID:28522984

  10. Applicability of the Compensatory Encoding Model in Foreign Language Reading: An Investigation with Chinese College English Language Learners.

    PubMed

    Han, Feifei

    2017-01-01

    While some first language (L1) reading models suggest that inefficient word recognition and small working memory tend to inhibit higher-level comprehension processes; the Compensatory Encoding Model maintains that slow word recognition and small working memory do not normally hinder reading comprehension, as readers are able to operate metacognitive strategies to compensate for inefficient word recognition and working memory limitation as long as readers process a reading task without time constraint. Although empirical evidence is accumulated for support of the Compensatory Encoding Model in L1 reading, there is lack of research for testing of the Compensatory Encoding Model in foreign language (FL) reading. This research empirically tested the Compensatory Encoding Model in English reading among Chinese college English language learners (ELLs). Two studies were conducted. Study one focused on testing whether reading condition varying time affects the relationship between word recognition, working memory, and reading comprehension. Students were tested on a computerized English word recognition test, a computerized Operation Span task, and reading comprehension in time constraint and non-time constraint reading. The correlation and regression analyses showed that the strength of association was much stronger between word recognition, working memory, and reading comprehension in time constraint than that in non-time constraint reading condition. Study two examined whether FL readers were able to operate metacognitive reading strategies as a compensatory way of reading comprehension for inefficient word recognition and working memory limitation in non-time constraint reading. The participants were tested on the same computerized English word recognition test and Operation Span test. They were required to think aloud while reading and to complete the comprehension questions. The think-aloud protocols were coded for concurrent use of reading strategies, classified into language-oriented strategies, content-oriented strategies, re-reading, pausing, and meta-comment. The correlation analyses showed that while word recognition and working memory were only significantly related to frequency of language-oriented strategies, re-reading, and pausing, but not with reading comprehension. Jointly viewed, the results of the two studies, complimenting each other, supported the applicability of the Compensatory Encoding Model in FL reading with Chinese college ELLs.

  11. Working memory span in mild cognitive impairment. Influence of processing speed and cognitive reserve.

    PubMed

    Facal, David; Juncos-Rabadán, Onésimo; Pereiro, Arturo X; Lojo-Seoane, Cristina

    2014-04-01

    Mild cognitive impairment (MCI) often includes episodic memory impairment, but can also involve other types of cognitive decline. Although previous studies have shown poorer performance of MCI patients in working memory (WM) span tasks, different MCI subgroups were not studied. In the present exploratory study, 145 participants underwent extensive cognitive evaluation, which included three different WM span tasks, and were classified into the following groups: multiple-domain amnestic MCI (mda-MCI), single-domain amnestic MCI (sda-MCI), and controls. General linear model was conducted by considering the WM span tasks as the within-subject factor; the group (mda-MCI, sda-MCI, and controls) as the inter-subject factor; and processing speed, vocabulary and age as covariates. Multiple linear regression models were also used to test the influence of processing speed, vocabulary, and other cognitive reserve (CR) proxies. Results indicate different levels of impairment of WM, with more severe impairment in mda-MCI patients. The differences were still present when processing resources and CR were controlled. Between-group differences can be understood as a manifestation of the greater severity and widespread memory impairment in mda-MCI patients and may contribute to a better understanding of continuum from normal controls to mda-MCI patients. Processing speed and CR have a limited influence on WM scores, reducing but not removing differences between groups.

  12. Anxiety and working memory capacity: A meta-analysis and narrative review.

    PubMed

    Moran, Tim P

    2016-08-01

    Cognitive deficits are now widely recognized to be an important component of anxiety. In particular, anxiety is thought to restrict the capacity of working memory by competing with task-relevant processes. The evidence for this claim, however, has been mixed. Although some studies have found restricted working memory in anxiety, others have not. Within studies that have found impairments, there is little agreement regarding the boundary conditions of the anxiety/WMC association. The aim of this review is to critically evaluate the evidence for anxiety-related deficits in working memory capacity. First, a meta-analysis of 177 samples (N = 22,061 individuals) demonstrated that self-reported measures of anxiety are reliably related to poorer performance on measures of working memory capacity (g = -.334, p < 10-29). This finding was consistent across complex span (e.g., OSPAN; g = -.342, k = 30, N = 3,196, p = .000001), simple span (e.g., digit span; g = -.318, k = 127, N = 17,547, p < 10-17), and dynamic span tasks (e.g., N-Back; g = -.437, k = 20, N = 1,318, p = .000003). Second, a narrative review of the literature revealed that anxiety, whether self-reported or experimentally induced, is related to poorer performance across a wide variety of tasks. Finally, the review identified a number of methodological limitations common in the literature as well as avenues for future research. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

  13. Administration of Neuropsychological Tests Using Interactive Voice Response Technology in the Elderly: Validation and Limitations

    PubMed Central

    Miller, Delyana Ivanova; Talbot, Vincent; Gagnon, Michèle; Messier, Claude

    2013-01-01

    Interactive voice response (IVR) systems are computer programs, which interact with people to provide a number of services from business to health care. We examined the ability of an IVR system to administer and score a verbal fluency task (fruits) and the digit span forward and backward in 158 community dwelling people aged between 65 and 92 years of age (full scale IQ of 68–134). Only six participants could not complete all tasks mostly due to early technical problems in the study. Participants were also administered the Wechsler Intelligence Scale fourth edition (WAIS-IV) and Wechsler Memory Scale fourth edition subtests. The IVR system correctly recognized 90% of the fruits in the verbal fluency task and 93–95% of the number sequences in the digit span. The IVR system typically underestimated the performance of participants because of voice recognition errors. In the digit span, these errors led to the erroneous discontinuation of the test: however the correlation between IVR scoring and clinical scoring was still high (93–95%). The correlation between the IVR verbal fluency and the WAIS-IV Similarities subtest was 0.31. The correlation between the IVR digit span forward and backward and the in-person administration was 0.46. We discuss how valid and useful IVR systems are for neuropsychological testing in the elderly. PMID:23950755

  14. Are factors related to dual-task performance in people with Parkinson's disease dependent on the type of dual task?

    PubMed

    Strouwen, Carolien; Molenaar, Esther A L M; Keus, Samyra H J; Münks, Liesbeth; Heremans, Elke; Vandenberghe, Wim; Bloem, Bastiaan R; Nieuwboer, Alice

    2016-02-01

    Impaired dual-task performance significantly impacts upon functional mobility in people with Parkinson's disease (PD). The aim of this study was to identify determinants of dual-task performance in people with PD in three different dual tasks to assess their possible task-dependency. We recruited 121 home-dwelling patients with PD (mean age 65.93 years; mean disease duration 8.67 years) whom we subjected to regular walking (control condition) and to three dual-task conditions: walking combined with a backwards Digit Span task, an auditory Stroop task and a Mobile Phone task. We measured dual-task gait velocity using the GAITRite mat and dual-task reaction times and errors on the concurrent tasks as outcomes. Motor, cognitive and descriptive variables which correlated to dual-task performance (p < 0.20) were entered into a stepwise forward multiple linear regression model. Single-task gait velocity and executive function, tested by the alternating intake test, was significantly associated with gait velocity during the Digit Span (R(2) = 0.65; p < 0.001), the Stroop (R(2) = 0.73; p < 0.001) and the Mobile Phone task (R(2) = 0.62; p < 0.001). In addition, disease severity proved correlated to gait velocity during the Stroop task. Age was a surplus determinant of gait velocity while using a mobile phone. Single-task gait velocity and executive function as measured by a verbal fluency switching task were independent determinants of dual-task gait performance in people with PD. In contrast to expectation, these factors were the same across different tasks, supporting the robustness of the findings. Future study needs to determine whether these factors predict dual-task abnormalities prospectively. Copyright © 2015 Elsevier Ltd. All rights reserved.

  15. Cognitive load selectively influences the interruptive effect of pain on attention.

    PubMed

    Moore, David J; Eccleston, Christopher; Keogh, Edmund

    2017-10-01

    Pain is known to interrupt attentional performance. Such interference effects seem to occur preferentially for tasks that are complex and/or difficult. However, few studies have directly manipulated memory load in the context of pain interference to test this view. Therefore, this study examines the effect of experimental manipulations of both memory load and pain on 3 tasks previously found to be sensitive to pain interference. Three experiments were conducted. A different task was examined in each experiment, each comprising of a high- and low-cognitive load versions of the task. Experiment 1 comprised an attention span (n-back) task, experiment 2 an attention switching task, and experiment 3 a divided attention task. Each task was conducted under painful and nonpainful conditions. Within the pain condition, an experimental thermal pain induction protocol was administered at the same time participants completed the task. The load manipulations were successful in all experiments. Pain-related interference occurred under the high-load condition but only for the attention span task. No effect of pain was found on either the attentional switching or divided attention task. These results suggest that while cognitive load may influence the interruptive effect of pain on attention, this effect may be selective. Because pain affected the high-load version of the n-back task but did not interrupt performance on attentional switching or dual-task paradigms, this means that our findings did not completely support our hypotheses. Future research should explore further the parameters and conditions under which pain-related interference occurs.

  16. 78 FR 6208 - Drawbridge Operating Regulations; Gulf Intracoastal Waterway, Belle Chasse, LA

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-01-30

    ... operating schedule that governs the Louisiana State Route 23 (LA 23) vertical lift span bridge, also known... State Route 23 (LA 23) vertical lift span bridge, also known as the Judge Perez Bridge, across the Gulf... 23 vertical lift span drawbridge across the Gulf Intracoastal Waterway (Algiers Alternate Route...

  17. Modeling Working Memory Tasks on the Item Level

    ERIC Educational Resources Information Center

    Luo, Dasen; Chen, Guopeng; Zen, Fanlin; Murray, Bronwyn

    2010-01-01

    Item responses to Digit Span and Letter-Number Sequencing were analyzed to develop a better-refined model of the two working memory tasks using the finite mixture (FM) modeling method. Models with ordinal latent traits were found to better account for the independent sources of the variability in the tasks than those with continuous traits, and…

  18. Visuospatial Working Memory in Intuitive Geometry, and in Academic Achievement in Geometry

    ERIC Educational Resources Information Center

    Giofre, David; Mammarella, Irene C.; Ronconi, Lucia; Cornoldi, Cesare

    2013-01-01

    A study was conducted on the involvement of visuospatial working memory (VSWM) in intuitive geometry and in school performance in geometry at secondary school. A total of 166 pupils were administered: (1) six VSWM tasks, comprising simple storage and complex span tasks; and (2) the intuitive geometry task devised by Dehaene, Izard, Pica, and…

  19. Happiness increases verbal and spatial working memory capacity where sadness does not: Emotion, working memory and executive control.

    PubMed

    Storbeck, Justin; Maswood, Raeya

    2016-08-01

    The effects of emotion on working memory and executive control are often studied in isolation. Positive mood enhances verbal and impairs spatial working memory, whereas negative mood enhances spatial and impairs verbal working memory. Moreover, positive mood enhances executive control, whereas negative mood has little influence. We examined how emotion influences verbal and spatial working memory capacity, which requires executive control to coordinate between holding information in working memory and completing a secondary task. We predicted that positive mood would improve both verbal and spatial working memory capacity because of its influence on executive control. Positive, negative and neutral moods were induced followed by completing a verbal (Experiment 1) or spatial (Experiment 2) working memory operation span task to assess working memory capacity. Positive mood enhanced working memory capacity irrespective of the working memory domain, whereas negative mood had no influence on performance. Thus, positive mood was more successful holding information in working memory while processing task-irrelevant information, suggesting that the influence mood has on executive control supersedes the independent effects mood has on domain-specific working memory.

  20. Effects of a Short Strategy Training on Metacognitive Monitoring across the Life-Span

    ERIC Educational Resources Information Center

    von der Linden, Nicole; Löffler, Elisabeth; Schneider, Wolfgang

    2015-01-01

    The present study was conducted to explore the potential positive influence of a short strategy training on metacognitive monitoring competencies covering a life-span approach. Participants of four age groups (3rd-grade children, adolescents, younger and older adults) concluded a paired-associate learning task. Additionally, they gave delayed…

  1. Working Memory Span Development: A Time-Based Resource-Sharing Model Account

    ERIC Educational Resources Information Center

    Barrouillet, Pierre; Gavens, Nathalie; Vergauwe, Evie; Gaillard, Vinciane; Camos, Valerie

    2009-01-01

    The time-based resource-sharing model (P. Barrouillet, S. Bernardin, & V. Camos, 2004) assumes that during complex working memory span tasks, attention is frequently and surreptitiously switched from processing to reactivate decaying memory traces before their complete loss. Three experiments involving children from 5 to 14 years of age…

  2. Working memory span in Persian-speaking children with speech sound disorders and normal speech development.

    PubMed

    Afshar, Mohamad Reza; Ghorbani, Ali; Rashedi, Vahid; Jalilevand, Nahid; Kamali, Mohamad

    2017-10-01

    The aim of this study was to compare working memory span in Persian-speaking preschool children with speech sound disorder (SSD) and their typically speaking peers. Additionally, the study aimed to examine Non-Word Repetition (NWR), Forward Digit Span (FDS) and Backward Digit Span (BDS) in four groups of children with varying severity levels of SSD. The participants in this study comprised 35 children with SSD and 35 typically developing (TD) children -matched for age and sex-as a control group. The participants were between the age range of 48 and 72 months. Two components of working memory including phonological loop and central executive were compared between two groups. We used two tasks (NWR and FDS) to assess phonological loop component, and one task (BDS) to assess central executive component. Percentage of correct consonants (PCC) was used to calculate the severity of SSD. Significant differences were observed between the two groups in all tasks that assess working memory (p < 0.001). In addition, the comparison of the phonological loop of working memory between the various severity groups indicated significant differences between different severities of both NWR and FDS tasks among the SSD children (p < 0.001). Nevertheless, comparison of the central executive between various severity groups, which was assessed with the BDS task, did not show any significant differences (p > 0.05). The result showed that PCC scores in TD children were associated with NWR (p < 0.001), FDS (p = 0.001), and BDS (p < 0.001). Furthermore, PCC scores in SSD children were associated with NWR and FDS (p < 0.001), but not with BDS (p > 0.05). The working memory skills were weaker in SSD children, in comparison to TD children. In addition, children with varying levels of severity of SSD differed in terms of NWR and FSD, but not BDS. Copyright © 2017 Elsevier B.V. All rights reserved.

  3. GluN2B-containing NMDA receptors and AMPA receptors in medial prefrontal cortex are necessary for odor span in rats.

    PubMed

    Davies, Don A; Greba, Quentin; Howland, John G

    2013-01-01

    Working memory is a type of short-term memory involved in the maintenance and manipulation of information essential for complex cognition. While memory span capacity has been extensively studied in humans as a measure of working memory, it has received considerably less attention in rodents. Our aim was to examine the role of the N-methyl-D-aspartate (NMDA) and α-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) glutamate receptors in odor span capacity using systemic injections or infusions of receptor antagonists into the medial prefrontal cortex (mPFC). Long Evans rats were trained on a well-characterized odor span task (OST). Initially, rats were trained to dig for a food reward in sand followed by training on a non-match to sample discrimination using sand scented with household spices. The rats were then required to perform a serial delayed non-match to sample procedure which was their odor span. Systemic injection of the broad spectrum NMDA receptor antagonist 3-(2-Carboxypiperazin-4-yl)propyl-1-phosphonic acid (CPP) (10 mg/kg) or the GluN2B-selective antagonist Ro 25-6981 (10 mg/kg but not 6 mg/kg) significantly reduced odor span capacity. Infusions of the GluN2B- selective antagonist Ro 25-6981 (2.5 μg/hemisphere) into mPFC reduced span capacity, an effect that was nearly significant (p = 0.069). Infusions of the AMPA receptor antagonist 6-cyano-7-nitroquinoxaline-2,3-dione (CNQX) (1.25 μg/hemisphere) into mPFC reduced span capacity and latency for the rats to make a choice in the task. These results demonstrate span capacity in rats depends on ionotropic glutamate receptor activation in the mPFC. Further understanding of the circuitry underlying span capacity may aid in the novel therapeutic drug development for persons with working memory impairments as a result of disorders such as schizophrenia and Alzheimer's disease.

  4. Neurofeedback training of EEG alpha rhythm enhances episodic and working memory.

    PubMed

    Hsueh, Jen-Jui; Chen, Tzu-Shan; Chen, Jia-Jin; Shaw, Fu-Zen

    2016-07-01

    Neurofeedback training (NFT) of the alpha rhythm has been used for several decades but is still controversial in regards to its trainability and effects on working memory. Alpha rhythm of the frontoparietal region are associated with either the intelligence or memory of healthy subjects and are also related to pathological states. In this study, alpha NFT effects on memory performances were explored. Fifty healthy participants were recruited and randomly assigned into a group receiving a 8-12-Hz amplitude (Alpha) or a group receiving a random 4-Hz amplitude from the range of 7 to 20 Hz (Ctrl). Three NFT sessions per week were conducted for 4 weeks. Working memory was assessed by both a backward digit span task and an operation span task, and episodic memory was assessed using a word pair task. Four questionnaires were used to assess anxiety, depression, insomnia, and cognitive function. The Ctrl group had no change in alpha amplitude and duration. In contrast, the Alpha group showed a progressive significant increase in the alpha amplitude and total alpha duration of the frontoparietal region. Accuracies of both working and episodic memories were significantly improved in a large proportion of participants of the Alpha group, particularly for those with remarkable alpha-amplitude increases. Scores of four questionnaires fell in a normal range before and after NFT. The current study provided supporting evidence for alpha trainability within a small session number compared with that of therapy. The findings suggested the enhancement of working and episodic memory through alpha NFT. Hum Brain Mapp 37:2662-2675, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  5. Spatial abilities across the adult life span.

    PubMed

    Borella, Erika; Meneghetti, Chiara; Ronconi, Lucia; De Beni, Rossana

    2014-02-01

    The study investigates age-related effects across the adult life span on spatial abilities (testing subabilities based on a distinction between spatial visualization, mental rotation, and perspective taking) and spatial self-assessments. The sample consisted of 454 participants (223 women and 231 men) from 20 to 91 years of age. Results showed nonlinear age-related effects for spatial visualization and perspective taking but linear effects for mental rotation; few or no age-related effects were found for spatial self-assessments. Working memory accounted for only a small proportion of the variance in all spatial tasks and had no effect on spatial self-assessments. Overall, our findings suggest that the influence of age on spatial skills across the adult life span is considerable, but the effects of age change as a function of the spatial task considered, and the effect on spatial self-assessment is more marginal.

  6. Work Skills for Prevocational Training.

    ERIC Educational Resources Information Center

    Skaggs, Donald Ray

    A prevocational work skills training program for moderately retarded students emphasizes the need for developmentally appropriate tasks, concern for increasing students' attention span, orderly arrangement within tasks, and increased proficiency after training. Major units in the program focus on concepts of similarity and difference, large and…

  7. 76 FR 72309 - Drawbridge Operation Regulations; Chelsea River, Chelsea and East Boston, MA

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-11-23

    ... installed new vertical lift bridge span will undergo testing for three weeks. This deviation requires a four hour advance notice for bridge openings during the lift span test period. DATES: This deviation is... facilities located upstream from the new bridge. The lift span at the new bridge will be operated by the...

  8. 39. View of bridge operators controls in the control house ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    39. View of bridge operators controls in the control house facing south. Controls on the right are for the south span and on the left for the north span. The large dial indicator towards the top of the picture is a position indicator for the south span. Also present is a marine radio for talking to marine traffic and control ropes for the horn and siren. - Henry Ford Bridge, Spanning Cerritos Channel, Los Angeles-Long Beach Harbor, Los Angeles, Los Angeles County, CA

  9. 76 FR 40237 - Drawbridge Operation Regulation; Illinois Waterway, Near Morris, IL

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-07-08

    ... allow removal of the existing lift span and installation of the replacement lift span. This deviation... position for eighty-four hours while the existing lift span is removed and the replacement lift span is...

  10. The relations between network-operation and topological-property in a scale-free and small-world network with community structure

    NASA Astrophysics Data System (ADS)

    Ma, Fei; Yao, Bing

    2017-10-01

    It is always an open, demanding and difficult task for generating available model to simulate dynamical functions and reveal inner principles from complex systems and networks. In this article, due to lots of real-life and artificial networks are built from series of simple and small groups (components), we discuss some interesting and helpful network-operation to generate more realistic network models. In view of community structure (modular topology), we present a class of sparse network models N(t , m) . At the moment, we capture the fact the N(t , 4) has not only scale-free feature, which means that the probability that a randomly selected vertex with degree k decays as a power-law, following P(k) ∼k-γ, where γ is the degree exponent, but also small-world property, which indicates that the typical distance between two uniform randomly chosen vertices grows proportionally to logarithm of the order of N(t , 4) , namely, relatively shorter diameter and lower average path length, simultaneously displays higher clustering coefficient. Next, as a new topological parameter correlating to reliability, synchronization capability and diffusion properties of networks, the number of spanning trees over a network is studied in more detail, an exact analytical solution for the number of spanning trees of the N(t , 4) is obtained. Based on the network-operation, part hub-vertex linking with each other will be helpful for structuring various network models and investigating the rules related with real-life networks.

  11. Running Memory for Clinical Handoffs: A Look at Active and Passive Processing.

    PubMed

    Anderson-Montoya, Brittany L; Scerbo, Mark W; Ramirez, Dana E; Hubbard, Thomas W

    2017-05-01

    The goal of the present study was to examine the effects of domain-relevant expertise on running memory and the ability to process handoffs of information. In addition, the role of active or passive processing was examined. Currently, there is little research that addresses how individuals with different levels of expertise process information in running memory when the information is needed to perform a real-world task. Three groups of participants differing in their level of clinical expertise (novice, intermediate, and expert) performed an abstract running memory span task and two tasks resembling real-world activities, a clinical handoff task and an air traffic control (ATC) handoff task. For all tasks, list length and the amount of information to be recalled were manipulated. Regarding processing strategy, all participants used passive processing for the running memory span and ATC tasks. The novices also used passive processing for the clinical task. The experts, however, appeared to use more active processing, and the intermediates fell in between. Overall, the results indicated that individuals with clinical expertise and a developed mental model rely more on active processing of incoming information for the clinical task while individuals with little or no knowledge rely on passive processing. The results have implications about how training should be developed to aid less experienced personnel identify what information should be included in a handoff and what should not.

  12. 78 FR 48608 - Drawbridge Operation Regulation; Atlantic Intracoastal Waterway (AIWW), Chesapeake, VA

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-08-09

    ... maintenance of the moveable spans on the structure. The current operating schedule for the bridge is set out... deviation from the operating schedule that governs the operation of the I64 Bridge across the Atlantic... necessary to facilitate maintenance work on the moveable spans. This temporary deviation allows the...

  13. Working Memory in Early-School-Age Children with Asperger's Syndrome

    ERIC Educational Resources Information Center

    Cui, Jifang; Gao, Dingguo; Chen, Yinghe; Zou, Xiaobing; Wang, Ya

    2010-01-01

    Using a battery of working memory span tasks and n-back tasks, this study aimed to explore working memory functions in early-school-age children with Asperger's syndrome (AS). Twelve children with AS and 29 healthy children matched on age and IQ were recruited. Results showed: (a) children with AS performed better in digit and word recall tasks,…

  14. A Processing Approach to the Working Memory/Long-Term Memory Distinction: Evidence from the Levels-of-Processing Span Task

    ERIC Educational Resources Information Center

    Rose, Nathan S.; Craik, Fergus I. M.

    2012-01-01

    Recent theories suggest that performance on working memory (WM) tasks involves retrieval from long-term memory (LTM). To examine whether WM and LTM tests have common principles, Craik and Tulving's (1975) levels-of-processing paradigm, which is known to affect LTM, was administered as a WM task: Participants made uppercase, rhyme, or…

  15. Measuring working memory capacity in children using adaptive tasks: Example validation of an adaptive complex span.

    PubMed

    Gonthier, Corentin; Aubry, Alexandre; Bourdin, Béatrice

    2018-06-01

    Working memory tasks designed for children usually present trials in order of ascending difficulty, with testing discontinued when the child fails a particular level. Unfortunately, this procedure comes with a number of issues, such as decreased engagement from high-ability children, vulnerability of the scores to temporary mind-wandering, and large between-subjects variations in number of trials, testing time, and proactive interference. To circumvent these problems, the goal of the present study was to demonstrate the feasibility of assessing working memory using an adaptive testing procedure. The principle of adaptive testing is to dynamically adjust the level of difficulty as the task progresses to match the participant's ability. We used this method to develop an adaptive complex span task (the ACCES) comprising verbal and visuo-spatial subtests. The task presents a fixed number of trials to all participants, allows for partial credit scoring, and can be used with children regardless of ability level. The ACCES demonstrated satisfying psychometric properties in a sample of 268 children aged 8-13 years, confirming the feasibility of using adaptive tasks to measure working memory capacity in children. A free-to-use implementation of the ACCES is provided.

  16. Balancing the Demands of Two Tasks: An Investigation of Cognitive-Motor Dual-Tasking in Relapsing Remitting Multiple Sclerosis.

    PubMed

    Butchard-MacDonald, Emma; Paul, Lorna; Evans, Jonathan J

    2018-03-01

    People with relapsing remitting multiple sclerosis (PwRRMS) suffer disproportionate decrements in gait under dual-task conditions, when walking and a cognitive task are combined. There has been much less investigation of the impact of cognitive demands on balance. This study investigated whether: (1) PwRRMS show disproportionate decrements in postural stability under dual-task conditions compared to healthy controls, and (2) dual-task decrements are associated with everyday dual-tasking difficulties. The impact of mood, fatigue, and disease severity on dual-tasking was also examined. A total of 34 PwRRMS and 34 matched controls completed cognitive (digit span) and balance (movement of center of pressure on Biosway on stable and unstable surfaces) tasks under single- and dual-task conditions. Everyday dual-tasking was measured using the Dual-Tasking Questionnaire. Mood was measured by the Hospital Anxiety & Depression Scale. Fatigue was measured via the Modified Fatigue Index Scale. No differences in age, gender, years of education, estimated pre-morbid IQ, or baseline digit span between groups. Compared with controls, PwRRMS showed significantly greater decrement in postural stability under dual-task conditions on an unstable surface (p=.007), but not a stable surface (p=.679). Balance decrement scores were not correlated with everyday dual-tasking difficulties or fatigue. Stable surface balance decrement scores were significantly associated with levels of anxiety (rho=0.527; p=.001) and depression (rho=0.451; p=.007). RRMS causes dual-tasking difficulties, impacting balance under challenging conditions, which may contribute to increased risk of gait difficulties and falls. The relationship between anxiety/depression and dual-task decrement suggests that emotional factors may be contributing to dual-task difficulties. (JINS, 2018, 24, 247-258).

  17. Lifespan development of pro- and anti-saccades: multiple regression models for point estimates.

    PubMed

    Klein, Christoph; Foerster, Friedrich; Hartnegg, Klaus; Fischer, Burkhart

    2005-12-07

    The comparative study of anti- and pro-saccade task performance contributes to our functional understanding of the frontal lobes, their alterations in psychiatric or neurological populations, and their changes during the life span. In the present study, we apply regression analysis to model life span developmental effects on various pro- and anti-saccade task parameters, using data of a non-representative sample of 327 participants aged 9 to 88 years. Development up to the age of about 27 years was dominated by curvilinear rather than linear effects of age. Furthermore, the largest developmental differences were found for intra-subject variability measures and the anti-saccade task parameters. Ageing, by contrast, had the shape of a global linear decline of the investigated saccade functions, lacking the differential effects of age observed during development. While these results do support the assumption that frontal lobe functions can be distinguished from other functions by their strong and protracted development, they do not confirm the assumption of disproportionate deterioration of frontal lobe functions with ageing. We finally show that the regression models applied here to quantify life span developmental effects can also be used for individual predictions in applied research contexts or clinical practice.

  18. Short-Term Memory Stages in Sign vs. Speech: The Source of the Serial Span Discrepancy

    PubMed Central

    Hall, Matthew L.

    2011-01-01

    Speakers generally outperform signers when asked to recall a list of unrelated verbal items. This phenomenon is well established, but its source has remained unclear. In this study, we evaluate the relative contribution of the three main processing stages of short-term memory – perception, encoding, and recall – in this effect. The present study factorially manipulates whether American Sign Language (ASL) or English was used for perception, memory encoding, and recall in hearing ASL-English bilinguals. Results indicate that using ASL during both perception and encoding contributes to the serial span discrepancy. Interestingly, performing recall in ASL slightly increased span, ruling out the view that signing is in general a poor choice for short-term memory. These results suggest that despite the general equivalence of sign and speech in other memory domains, speech-based representations are better suited for the specific task of perception and memory encoding of a series of unrelated verbal items in serial order through the phonological loop. This work suggests that interpretation of performance on serial recall tasks in English may not translate straightforwardly to serial tasks in sign language. PMID:21450284

  19. Impaired Letter-String Processing in Developmental Dyslexia: What Visual-to-Phonology Code Mapping Disorder?

    ERIC Educational Resources Information Center

    Valdois, Sylviane; Lassus-Sangosse, Delphine; Lobier, Muriel

    2012-01-01

    Poor parallel letter-string processing in developmental dyslexia was taken as evidence of poor visual attention (VA) span, that is, a limitation of visual attentional resources that affects multi-character processing. However, the use of letter stimuli in oral report tasks was challenged on its capacity to highlight a VA span disorder. In…

  20. Developmental Dyslexia: Exploring How Much Phonological and Visual Attention Span Disorders Are Linked to Simultaneous Auditory Processing Deficits

    ERIC Educational Resources Information Center

    Lallier, Marie; Donnadieu, Sophie; Valdois, Sylviane

    2013-01-01

    The simultaneous auditory processing skills of 17 dyslexic children and 17 skilled readers were measured using a dichotic listening task. Results showed that the dyslexic children exhibited difficulties reporting syllabic material when presented simultaneously. As a measure of simultaneous visual processing, visual attention span skills were…

  1. Time Constraints and Resource Sharing in Adults' Working Memory Spans

    ERIC Educational Resources Information Center

    Barrouillet, Pierre; Bernardin, Sophie; Camos, Valerie

    2004-01-01

    This article presents a new model that accounts for working memory spans in adults, the time-based resource-sharing model. The model assumes that both components (i.e., processing and maintenance) of the main working memory tasks require attention and that memory traces decay as soon as attention is switched away. Because memory retrievals are…

  2. Do Dyslexic Individuals Present a Reduced Visual Attention Span? Evidence from Visual Recognition Tasks of Non-Verbal Multi-Character Arrays

    ERIC Educational Resources Information Center

    Yeari, Menahem; Isser, Michal; Schiff, Rachel

    2017-01-01

    A controversy has recently developed regarding the hypothesis that developmental dyslexia may be caused, in some cases, by a reduced visual attention span (VAS). To examine this hypothesis, independent of phonological abilities, researchers tested the ability of dyslexic participants to recognize arrays of unfamiliar visual characters. Employing…

  3. Developmental Change in Proactive Interference across the Life Span: Evidence from Two Working Memory Tasks

    ERIC Educational Resources Information Center

    Loosli, Sandra V.; Rahm, Benjamin; Unterrainer, Josef M.; Weiller, Cornelius; Kaller, Christoph P.

    2014-01-01

    Working memory (WM) as the ability to temporarily maintain and manipulate various kinds of information is known to be affected by proactive interference (PI) from previously relevant contents, but studies on developmental changes in the susceptibility to PI are scarce. In the present study, we investigated life span development of item-specific…

  4. MIT CSAIL and Lincoln Laboratory Task Force Report

    DTIC Science & Technology

    2016-08-01

    projects have been very diverse, spanning several areas of CSAIL concentration, including robotics, big data analytics , wireless communications...spanning several areas of CSAIL concentration, including robotics, big data analytics , wireless communications, computing architectures and...to machine learning systems and algorithms, such as recommender systems, and “Big Data ” analytics . Advanced computing architectures broadly refer to

  5. On the Nature of Forgetting and the Processing--Storage Relationship in Reading Span Performance

    ERIC Educational Resources Information Center

    Saito, Satoru; Miyake, Akira

    2004-01-01

    Four experiments examined the nature of forgetting and the processing--storage relationship during performance on a prevalent working memory task, the reading span test. Using two different presentation paradigms, Experiments 1 and 2 replicated Towse, Hitch, and Hutton's (1998, 2000) finding that the Short-Final lists, which presented a long…

  6. Predicting performance on the Columbia Card Task: effects of personality characteristics, mood, and executive functions.

    PubMed

    Buelow, Melissa T

    2015-04-01

    Behavioral measures of risky decision making are frequently used by researchers and clinicians; however, most of these measures are strongly associated with personality characteristics and state mood. The present study sought to examine personality, mood, and executive function predictors of performance on a newer measure of decision making, the Columbia Card Task (CCT). Participants were 489 undergraduate students who completed either the hot or cold version of the CCT as well as measures of state mood, impulsive sensation seeking, behavioral inhibition and activation systems, and executive functions (Wisconsin Card Sort Task; Digit Span). Results indicated that performance on the CCT-cold was predicted by Wisconsin Card Sort Task errors, and Digit Span predicted the CCT-hot. In addition, significant correlations were found between the CCT information use variables and the predictor variables. Implications for the utility of the CCT as a clinical instrument and its relationship with other measures of decision making are discussed. © The Author(s) 2014.

  7. Syntactic Recursion Facilitates and Working Memory Predicts Recursive Theory of Mind

    PubMed Central

    Arslan, Burcu; Hohenberger, Annette; Verbrugge, Rineke

    2017-01-01

    In this study, we focus on the possible roles of second-order syntactic recursion and working memory in terms of simple and complex span tasks in the development of second-order false belief reasoning. We tested 89 Turkish children in two age groups, one younger (4;6–6;5 years) and one older (6;7–8;10 years). Although second-order syntactic recursion is significantly correlated with the second-order false belief task, results of ordinal logistic regressions revealed that the main predictor of second-order false belief reasoning is complex working memory span. Unlike simple working memory and second-order syntactic recursion tasks, the complex working memory task required processing information serially with additional reasoning demands that require complex working memory strategies. Based on our results, we propose that children’s second-order theory of mind develops when they have efficient reasoning rules to process embedded beliefs serially, thus overcoming a possible serial processing bottleneck. PMID:28072823

  8. Working memory training and transfer in older adults.

    PubMed

    Richmond, Lauren L; Morrison, Alexandra B; Chein, Jason M; Olson, Ingrid R

    2011-12-01

    There has been a great deal of interest, both privately and commercially, in using working memory training exercises to improve general cognitive function. However, many of the laboratory findings for older adults, a group in which this training is of utmost interest, are discouraging due to the lack of transfer to other tasks and skills. Importantly, improvements in everyday functioning remain largely unexamined in relation to WM training. We trained working memory in older adults using a task that encourages transfer in young adults (Chein & Morrison, 2010). We tested transfer to measures of working memory (e.g., Reading Span), everyday cognitive functioning [the Test of Everyday Attention (TEA) and the California Verbal Learning Test (CVLT)], and other tasks of interest. Relative to controls, trained participants showed transfer improvements in Reading Span and the number of repetitions on the CVLT. Training group participants were also significantly more likely to self-report improvements in everyday attention. Our findings support the use of ecological tasks as a measure of transfer in an older adult population.

  9. The visual attention span deficit in Chinese children with reading fluency difficulty.

    PubMed

    Zhao, Jing; Liu, Menglian; Liu, Hanlong; Huang, Chen

    2018-02-01

    With reading development, some children fail to learn to read fluently. However, reading fluency difficulty (RFD) has not been fully investigated. The present study explored the underlying mechanism of RFD from the aspect of visual attention span. Fourteen Chinese children with RFD and fourteen age-matched normal readers participated. The visual 1-back task was adopted to examine visual attention span. Reaction time and accuracy were recorded, and relevant d-prime (d') scores were computed. Results showed that children with RFD exhibited lower accuracy and lower d' values than the controls did in the visual 1-back task, revealing a visual attention span deficit. Further analyses on d' values revealed that the attention distribution seemed to exhibit an inverted U-shaped pattern without lateralization for normal readers, but a W-shaped pattern with a rightward bias for children with RFD, which was discussed based on between-group variation in reading strategies. Results of the correlation analyses showed that visual attention span was associated with reading fluency at the sentence level for normal readers, but was related to reading fluency at the single-character level for children with RFD. The different patterns in correlations between groups revealed that visual attention span might be affected by the variation in reading strategies. The current findings extend previous data from alphabetic languages to Chinese, a logographic language with a particularly deep orthography, and have implications for reading-dysfluency remediation. Copyright © 2017 Elsevier Ltd. All rights reserved.

  10. 76 FR 12 - Drawbridge Operation Regulations; New Haven Harbor, Quinnipiac and Mill Rivers, New Haven, CT

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-01-03

    ... to keep one lift span closed to facilitate scheduled bridge maintenance. DATES: This deviation is... temporary deviation the Ferry Street Bridge may keep one lift span in the closed position from 8 a.m. on... January 13, 2011. One lift span shall remain operational at all times. In accordance with 33 CFR 117.35(e...

  11. Rethinking the connection between working memory and language impairment.

    PubMed

    Archibald, Lisa M D; Harder Griebeling, Katherine

    2016-05-01

    Working memory deficits have been found for children with specific language impairment (SLI) on tasks imposing increasing short-term memory load with or without additional, consistent (and simple) processing load. To examine the processing function of working memory in children with low language (LL) by employing tasks imposing increasing processing loads with constant storage demands individually adjusted based on each participant's short-term memory capacity. School-age groups with LL (n = 17) and typical language with either average (n = 28) or above-average nonverbal intelligence (n = 15) completed complex working memory-span tasks varying processing load while keeping storage demands constant, varying storage demands while keeping processing load constant, simple storage-span tasks, and measures of language and nonverbal intelligence. Teachers completed questionnaires about cognition and learning. Significantly lower scores were found for the LL than either matched group on storage-based tasks, but no group differences were found on the tasks varying processing load. Teachers' ratings of oral expression and mathematics abilities discriminated those who did or did not complete the most challenging cognitive tasks. The results implicate a deficit in the phonological storage but not in the central executive component of working memory for children with LL. Teacher ratings may reveal personality traits related to perseverance of effort in cognitive research. © 2015 Royal College of Speech and Language Therapists.

  12. The impact of cognitive load on delayed recall.

    PubMed

    Camos, Valérie; Portrat, Sophie

    2015-08-01

    Recent studies have suggested that long-term retention of items studied in a working memory span task depends on the refreshing of memory items-more specifically, on the number of refreshing opportunities. However, it was previously shown that refreshing depends on the cognitive load of the concurrent task introduced in the working memory span task. Thus, cognitive load should determine the long-term retention of items assessed in a delayed-recall test if such retention relies on refreshing. In two experiments, while the amount of refreshing opportunities remained constant, we varied the cognitive load of the concurrent task by either introducing tasks differing in their attentional demands or varying the pace of the concurrent task. To verify that this effect was related to refreshing and not to any maintenance mechanism, we also manipulated the availability of subvocal rehearsal. Replicating previous results, increasing cognitive load reduced immediate recall. This increase also had a detrimental effect on delayed recall. Conversely, the addition of concurrent articulation reduced immediate but not delayed recall. This study shows that both working and episodic memory traces depend on the cognitive load of the concurrent task, whereas the use of rehearsal affects only working memory performance. These findings add further evidence of the dissociation between subvocal rehearsal and attentional refreshing.

  13. EEG activity during the spatial span task in young men: Differences between short-term and working memory.

    PubMed

    Guevara, Miguel Angel; Cruz Paniagua, Edwin Iván; Hernández González, Marisela; Sandoval Carrillo, Ivett Karina; Almanza Sepúlveda, Mayra Linné; Hevia Orozco, Jorge Carlos; Amezcua Gutiérrez, Claudia

    2018-03-15

    Short-term memory and working memory are two closely-related concepts that involve the prefrontal and parietal areas. These two types of memory have been evaluated by means of the spatial span task in its forward and backward conditions, respectively. To determine possible neurofunctional differences between them, this study recorded electroencephalographic activity (EEG) in the frontopolar (Fp1, Fp2), dorsolateral (F3, F4), and parietal (P3 and P4) areas during performance of the forward and backward conditions of this task in young men. The backward condition (an indicator of working memory) was characterized by fewer correct answers, higher absolute power (AP) of the delta band in dorsolateral areas, and a lower correlation between frontopolar and dorsolateral regions in the fast bands (alpha, beta and gamma), mainly in the right hemisphere. The prefrontal EEG changes during backward performance may be associated with the higher attentional demands and inhibition processes required to invert the order of reproduction of a sequence. These data provide evidence that the forward and backward conditions of the spatial span task can be distinguished on the basis of neurofunctional activity and performance, and that each one is associated with a distinct pattern of electrical activity and synchronization between prefrontal areas. The higher AP of the delta band and lower correlation of the fast bands, particularly between right prefrontal areas during the backward condition of this visuospatial task, suggest greater participation by the right prefrontal areas in working memory. Copyright © 2018 Elsevier B.V. All rights reserved.

  14. Cognitive features of psychotic states arising in late life (late paraphrenia).

    PubMed

    Almeida, O P; Howard, R J; Levy, R; David, A S; Morris, R G; Sahakian, B J

    1995-07-01

    The cognitive performance of 47 elderly psychotic patients with onset of symptoms in late life (late paraphrenia) was compared to that of 33 controls matched for age, sex, ethnic origin, number of years of education, and pre-morbid IQ as measured by the NART. Neuropsychological indices of general cognitive functioning (MMSE, CAMCOG, WAIS-R verbal and performance scores) showed that patients were performing the tasks at a significantly lower level than controls. Patients also showed a trend to have a lower span capacity than controls, particularly at the spatial span subtest. There was no obvious impairment of learning as measured by the digit and spatial recurring span tasks nor of simultaneous matching-to-sample ability. However, patients' performance on a delayed-matching-to-sample procedure was significantly worse than that of controls. In addition, patients performed worse than controls on the Recognition Memory Test for Faces, but not for Words. Finally, the performance of patients on tests assessing executive functioning (Verbal Fluency Test, Computerized Extra and Intra-Dimensional Shift Task, Computerized Spatial Working Memory Task, and Computerized Tower of London Task) was consistently worse than that of controls. These results suggest that psychotic states arising in late life are predominantly associated with a decline on measures of general cognitive ability and executive functioning. The neuropsychological meaning of these findings is discussed in the light of cognitive models of psychotic symptoms, as well as of schizophrenia and dementia research. We concluded that the lack of a clear pattern of impairment among these patients may be the result of their clinical and cognitive diversity.

  15. Promoting the experimental dialogue between working memory and chunking: Behavioral data and simulation.

    PubMed

    Portrat, Sophie; Guida, Alessandro; Phénix, Thierry; Lemaire, Benoît

    2016-04-01

    Working memory (WM) is a cognitive system allowing short-term maintenance and processing of information. Maintaining information in WM consists, classically, in rehearsing or refreshing it. Chunking could also be considered as a maintenance mechanism. However, in the literature, it is more often used to explain performance than explicitly investigated within WM paradigms. Hence, the aim of the present paper was (1) to strengthen the experimental dialogue between WM and chunking, by studying the effect of acronyms in a computer-paced complex span task paradigm and (2) to formalize explicitly this dialogue within a computational model. Young adults performed a WM complex span task in which they had to maintain series of 7 letters for further recall while performing a concurrent location judgment task. The series to be remembered were either random strings of letters or strings containing a 3-letter acronym that appeared in position 1, 3, or 5 in the series. Together, the data and simulations provide a better understanding of the maintenance mechanisms taking place in WM and its interplay with long-term memory. Indeed, the behavioral WM performance lends evidence to the functional characteristics of chunking that seems to be, especially in a WM complex span task, an attentional time-based mechanism that certainly enhances WM performance but also competes with other processes at hand in WM. Computational simulations support and delineate such a conception by showing that searching for a chunk in long-term memory involves attentionally demanding subprocesses that essentially take place during the encoding phases of the task.

  16. Automatic motor task selection via a bandit algorithm for a brain-controlled button

    NASA Astrophysics Data System (ADS)

    Fruitet, Joan; Carpentier, Alexandra; Munos, Rémi; Clerc, Maureen

    2013-02-01

    Objective. Brain-computer interfaces (BCIs) based on sensorimotor rhythms use a variety of motor tasks, such as imagining moving the right or left hand, the feet or the tongue. Finding the tasks that yield best performance, specifically to each user, is a time-consuming preliminary phase to a BCI experiment. This study presents a new adaptive procedure to automatically select (online) the most promising motor task for an asynchronous brain-controlled button. Approach. We develop for this purpose an adaptive algorithm UCB-classif based on the stochastic bandit theory and design an EEG experiment to test our method. We compare (offline) the adaptive algorithm to a naïve selection strategy which uses uniformly distributed samples from each task. We also run the adaptive algorithm online to fully validate the approach. Main results. By not wasting time on inefficient tasks, and focusing on the most promising ones, this algorithm results in a faster task selection and a more efficient use of the BCI training session. More precisely, the offline analysis reveals that the use of this algorithm can reduce the time needed to select the most appropriate task by almost half without loss in precision, or alternatively, allow us to investigate twice the number of tasks within a similar time span. Online tests confirm that the method leads to an optimal task selection. Significance. This study is the first one to optimize the task selection phase by an adaptive procedure. By increasing the number of tasks that can be tested in a given time span, the proposed method could contribute to reducing ‘BCI illiteracy’.

  17. Behavioral and Neural Correlates of Executive Function: Interplay between Inhibition and Updating Processes.

    PubMed

    Kim, Na Young; Wittenberg, Ellen; Nam, Chang S

    2017-01-01

    This study investigated the interaction between two executive function processes, inhibition and updating, through analyses of behavioral, neurophysiological, and effective connectivity metrics. Although, many studies have focused on behavioral effects of executive function processes individually, few studies have examined the dynamic causal interactions between these two functions. A total of twenty participants from a local university performed a dual task combing flanker and n-back experimental paradigms, and completed the Operation Span Task designed to measure working memory capacity. We found that both behavioral (accuracy and reaction time) and neurophysiological (P300 amplitude and alpha band power) metrics on the inhibition task (i.e., flanker task) were influenced by the updating load (n-back level) and modulated by working memory capacity. Using independent component analysis, source localization (DIPFIT), and Granger Causality analysis of the EEG time-series data, the present study demonstrated that manipulation of cognitive demand in a dual executive function task influenced the causal neural network. We compared connectivity across three updating loads (n-back levels) and found that experimental manipulation of working memory load enhanced causal connectivity of a large-scale neurocognitive network. This network contains the prefrontal and parietal cortices, which are associated with inhibition and updating executive function processes. This study has potential applications in human performance modeling and assessment of mental workload, such as the design of training materials and interfaces for those performing complex multitasking under stress.

  18. The relationship between sustained inattentional blindness and working memory capacity.

    PubMed

    Beanland, Vanessa; Chan, Esther Hiu Chung

    2016-04-01

    Inattentional blindness, whereby observers fail to detect unexpected stimuli, has been robustly demonstrated in a range of situations. Originally research focused primarily on how stimulus characteristics and task demands affect inattentional blindness, but increasingly studies are exploring the influence of observer characteristics on the detection of unexpected stimuli. It has been proposed that individual differences in working memory capacity predict inattentional blindness, on the assumption that higher working memory capacity confers greater attentional capacity for processing unexpected stimuli. Unfortunately, empirical investigations of the association between inattentional blindness and working memory capacity have produced conflicting findings. To help clarify this relationship, we examined the relationship between inattentional blindness and working memory capacity in two samples (Ns = 195, 147) of young adults. We used three common variants of sustained inattentional blindness tasks, systematically manipulating the salience of the unexpected stimulus and primary task practice. Working memory capacity, measured by automated operation span (both Experiments 1 & 2) and N-back (Experiment 1 only) tasks, did not predict detection of the unexpected stimulus in any of the inattentional blindness tasks tested. Together with previous research, this undermines claims that there is a robust relationship between inattentional blindness and working memory capacity. Rather, it appears that any relationship between inattentional blindness and working memory is either too small to have practical significance or is moderated by other factors and consequently varies with attributes such as the sample characteristics within a given study.

  19. Effect of Sudarshan Kriya (meditation) on gamma, alpha, and theta rhythm during working memory task.

    PubMed

    Chandra, Sushil; Sharma, Greeshma; Mittal, Alok Prakash; Jha, Devendra

    2016-01-01

    The present study focuses on analyzing the effects of Sudarshan Kriya yoga (SKY) on brain signals during a working memory (WM) task. To envision the significant effects of SKY on WM capacity (WMC), we chose a control group for contriving a cogent comparison that could be corroborated using statistical tests. A total of 25 subjects were taken in the study, of which 10 were allotted to a control group and 15 to an experimental group. Electroencephalograph was taken during a WM task, which was an automated operation span test before and after SKY with 90 days intervals. No SKY was given to the control group. t-test and one-way ANOVA were applied. SKY promoted the efficient use of energy and power spectral density (PSD) for different brain rhythms in the desired locations as depicted by the gamma (F8 channel), alpha, and theta 2 (F7 and FC5) bands. It was found that gamma PSD reduced for both phases of memory in the experimental group. Alpha energy increased during the retrieval phase in the experimental group after SKY. Theta 1 rhythm was not affected by SKY, but theta 2 had shown left hemispheric activation. Theta rhythm was associated with memory consolidation. SKY had shown minimized energy losses while performing the task. SKY can improve WMC by changing the brain rhythms such that energy is utilized efficiently in performing the task.

  20. 77 FR 25591 - Drawbridge Operation Regulation; Intracoastal Waterway, Chesapeake, VA

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-05-01

    ... replacing the lift joints of the drawbridge. This deviation restricts operation of the draw span, allowing... and to perform periodic maintenance. To facilitate replacement of the lift joints of the draw span...

  1. Episodic Long-Term Memory of Spoken Discourse Masked by Speech: What Is the Role for Working Memory Capacity?

    ERIC Educational Resources Information Center

    Sorqvist, Patrik; Ronnberg, Jerker

    2012-01-01

    Purpose: To investigate whether working memory capacity (WMC) modulates the effects of to-be-ignored speech on the memory of materials conveyed by to-be-attended speech. Method: Two tasks (reading span, Daneman & Carpenter, 1980; Ronnberg et al., 2008; and size-comparison span, Sorqvist, Ljungberg, & Ljung, 2010) were used to measure individual…

  2. User-assisted visual search and tracking across distributed multi-camera networks

    NASA Astrophysics Data System (ADS)

    Raja, Yogesh; Gong, Shaogang; Xiang, Tao

    2011-11-01

    Human CCTV operators face several challenges in their task which can lead to missed events, people or associations, including: (a) data overload in large distributed multi-camera environments; (b) short attention span; (c) limited knowledge of what to look for; and (d) lack of access to non-visual contextual intelligence to aid search. Developing a system to aid human operators and alleviate such burdens requires addressing the problem of automatic re-identification of people across disjoint camera views, a matching task made difficult by factors such as lighting, viewpoint and pose changes and for which absolute scoring approaches are not best suited. Accordingly, we describe a distributed multi-camera tracking (MCT) system to visually aid human operators in associating people and objects effectively over multiple disjoint camera views in a large public space. The system comprises three key novel components: (1) relative measures of ranking rather than absolute scoring to learn the best features for matching; (2) multi-camera behaviour profiling as higher-level knowledge to reduce the search space and increase the chance of finding correct matches; and (3) human-assisted data mining to interactively guide search and in the process recover missing detections and discover previously unknown associations. We provide an extensive evaluation of the greater effectiveness of the system as compared to existing approaches on industry-standard i-LIDS multi-camera data.

  3. Contextual knowledge reduces demands on working memory during reading.

    PubMed

    Miller, Lisa M Soederberg; Cohen, Jason A; Wingfield, Arthur

    2006-09-01

    An experiment is reported in which young, middle-aged, and older adults read and recalled ambiguous texts either with or without the topic title that supplied contextual knowledge. Within each of the age groups, the participants were divided into those with high or low working memory (WM) spans, with available WM capacity further manipulated by the presence or absence of an auditory target detection task concurrent with the reading task. Differences in reading efficiency (reading time per proposition recalled) between low WM span and high WM span groups were greater among readers who had access to contextual knowledge relative to those who did not, suggesting that contextual knowledge reduces demands on WM capacity. This position was further supported by the finding that increased age and attentional demands, two factors associated with reduced WM capacity, exaggerated the benefits of contextual knowledge on reading efficiency. The relative strengths of additional potential predictors of reading efficiency (e.g., interest, effort, and memory beliefs), along with knowledge, WM span, and age, are reported. Findings showed that contextual knowledge was the strongest predictor of reading efficiency even after controlling for the effects of all of the other predictors.

  4. Studying Different Tasks of Implicit Learning across Multiple Test Sessions Conducted on the Web

    PubMed Central

    Sævland, Werner; Norman, Elisabeth

    2016-01-01

    Implicit learning is usually studied through individual performance on a single task, with the most common tasks being the Serial Reaction Time (SRT) task, the Dynamic System Control (DSC) task, and Artificial Grammar Learning (AGL). Few attempts have been made to compare performance across different implicit learning tasks within the same study. The current study was designed to explore the relationship between performance on the DSC Sugar factory task and the Alternating Serial Reaction Time (ASRT) task. We also addressed another limitation of traditional implicit learning experiments, namely that implicit learning is usually studied in laboratory settings over a restricted time span lasting for less than an hour. In everyday situations, implicit learning is assumed to involve a gradual accumulation of knowledge across several learning episodes over a longer time span. One way to increase the ecological validity of implicit learning experiments could be to present the learning material repeatedly across shorter test sessions. This can most easily be done by using a web-based setup in which participants can access the material from home. We therefore created an online web-based system for measuring implicit learning that could be administered in either single or multiple sessions. Participants (n = 66) were assigned to either a single session or a multiple session condition. Learning occurred on both tasks, and awareness measures suggested that acquired knowledge was not fully conscious on either of the tasks. Learning and the degree of conscious awareness of the learned regularities were compared across conditions and tasks. On the DSC task, performance was not affected by whether learning had taken place in one or over multiple sessions. On the ASRT task, RT improvement across blocks was larger in the multiple-session condition. Learning in the two tasks was not related. PMID:27375512

  5. DRD4 long allele carriers show heightened attention to high-priority items relative to low-priority items.

    PubMed

    Gorlick, Marissa A; Worthy, Darrell A; Knopik, Valerie S; McGeary, John E; Beevers, Christopher G; Maddox, W Todd

    2015-03-01

    Humans with seven or more repeats in exon III of the DRD4 gene (long DRD4 carriers) sometimes demonstrate impaired attention, as seen in attention-deficit hyperactivity disorder, and at other times demonstrate heightened attention, as seen in addictive behavior. Although the clinical effects of DRD4 are the focus of much work, this gene may not necessarily serve as a "risk" gene for attentional deficits, but as a plasticity gene where attention is heightened for priority items in the environment and impaired for minor items. Here we examine the role of DRD4 in two tasks that benefit from selective attention to high-priority information. We examine a category learning task where performance is supported by focusing on features and updating verbal rules. Here, selective attention to the most salient features is associated with good performance. In addition, we examine the Operation Span (OSPAN) task, a working memory capacity task that relies on selective attention to update and maintain items in memory while also performing a secondary task. Long DRD4 carriers show superior performance relative to short DRD4 homozygotes (six or less tandem repeats) in both the category learning and OSPAN tasks. These results suggest that DRD4 may serve as a "plasticity" gene where individuals with the long allele show heightened selective attention to high-priority items in the environment, which can be beneficial in the appropriate context.

  6. DRD4 Long Allele Carriers Show Heightened Attention to High-Priority Items Relative to Low-Priority Items

    PubMed Central

    Gorlick, Marissa A.; Worthy, Darrell A.; Knopik, Valerie S.; McGeary, John E.; Beevers, Christopher G.; Maddox, W. Todd

    2014-01-01

    Humans with 7 or more repeats in exon III of the DRD4 gene (long DRD4 carriers) sometimes demonstrate impaired attention, as seen in ADHD, and at other times demonstrate heightened attention, as seen in addictive behavior. Though the clinical effects of DRD4 are the focus of much work, this gene may not necessarily serve as a ‘risk’ gene for attentional deficits, but as a plasticity gene where attention is heightened for priority items in the environment and impaired for minor items. Here we examine the role of DRD4 in two tasks that benefit from selective attention to high-priority information. We examine a category learning task where performance is supported by focusing on features and updating verbal rules. Here selective attention to the most salient features is associated with good performance. In addition, we examine the Operation Span Task (OSPAN), a working memory capacity task that relies on selective attention to update and maintain items in memory while also performing a secondary task. Long DRD4 carriers show superior performance relative to short DRD4 homozygotes (six or less tandem repeats) in both the category learning and OSPAN tasks. These results suggest that DRD4 may serve as a ‘plasticity’ gene where individuals with the long allele show heightened selective attention to high-priority items in the environment, which can be beneficial in the appropriate context. PMID:25244120

  7. Role of Working Memory in Children's Understanding Spoken Narrative: A Preliminary Investigation

    ERIC Educational Resources Information Center

    Montgomery, James W.; Polunenko, Anzhela; Marinellie, Sally A.

    2009-01-01

    The role of phonological short-term memory (PSTM), attentional resource capacity/allocation, and processing speed on children's spoken narrative comprehension was investigated. Sixty-seven children (6-11 years) completed a digit span task (PSTM), concurrent verbal processing and storage (CPS) task (resource capacity/allocation), auditory-visual…

  8. Age-Related Intraindividual Performance Variability with Practice

    ERIC Educational Resources Information Center

    Miller, Suzanne Bonneau; Odell, Katharine H.

    2007-01-01

    Fluctuations in cognitive task performance in older individuals have been reported. To examine intraindividual variability as a function of practice, 34 younger and 34 older female participants, aged 20-30 years and 70-82 years, respectively, performed a reading span task 16 times over four sessions. Each individual's recall accuracy was analyzed…

  9. The Structure of Visuospatial Memory in Adulthood

    ERIC Educational Resources Information Center

    Mammarella, Irene C.; Borella, Erika; Pastore, Massimiliano; Pazzaglia, Francesca

    2013-01-01

    The present study aimed to investigate the structure of visuospatial memory in adulthood. Adults 40-89 years of age (n = 160) performed simple storage and complex visuospatial span tasks. Simple storage tasks were distinguished into three presentation formats: (i) visual, which involved maintaining shapes and textures; (ii) spatial-sequential,…

  10. Everyday problem solving across the adult life span: solution diversity and efficacy.

    PubMed

    Mienaltowski, Andrew

    2011-10-01

    Everyday problem solving involves examining the solutions that individuals generate when faced with problems that take place in their everyday experiences. Problems can range from medication adherence and meal preparation to disagreeing with a physician over a recommended medical procedure or compromising with extended family members over where to host Thanksgiving dinner. Across the life span, research has demonstrated divergent patterns of change in performance based on the type of everyday problems used as well as based on the way that problem-solving efficacy is operationally defined. Advancing age is associated with worsening performance when tasks involve single-solution or fluency-based definitions of effectiveness. However, when efficacy is defined in terms of the diversity of strategies used, as well as by the social and emotional impact of solution choice on the individual, performance is remarkably stable and sometimes even improves in the latter half of life. This article discusses how both of these approaches to everyday problem solving inform research on the influence that aging has on everyday functioning. © 2011 New York Academy of Sciences.

  11. Everyday problem solving across the adult life span: solution diversity and efficacy

    PubMed Central

    Mienaltowski, Andrew

    2013-01-01

    Everyday problem solving involves examining the solutions that individuals generate when faced with problems that take place in their everyday experiences. Problems can range from medication adherence and meal preparation to disagreeing with a physician over a recommended medical procedure or compromising with extended family members over where to host Thanksgiving dinner. Across the life span, research has demonstrated divergent patterns of change in performance based on the type of everyday problems used as well as based on the way that problem-solving efficacy is operationally defined. Advancing age is associated with worsening performance when tasks involve single-solution or fluency-based definitions of effectiveness. However, when efficacy is defined in terms of the diversity of strategies used, as well as by the social and emotional impact of solution choice on the individual, performance is remarkably stable and sometimes even improves in the latter half of life. This article discusses how both of these approaches to everyday problem solving inform research on the influence that aging has on everyday functioning. PMID:22023569

  12. Is the frontal dysexecutive syndrome due to a working memory deficit? Evidence from patients with stroke.

    PubMed

    Roussel, Martine; Dujardin, Kathy; Hénon, Hilde; Godefroy, Olivier

    2012-07-01

    Although frontal dysexecutive disorders are frequently considered to be due to working memory deficit, this has not been systematically examined and very little evidence is available for impairment of working memory in frontal damage. The objective of this study was to examine the components of working memory, their anatomy and the relations with executive functions in patients with stroke involving the frontal or posterior cortex. The study population consisted of 29 patients (frontal: n=17; posterior: n=12) and 29 matched controls. Phonological loop (letter and word spans, phonological store; rehearsal process), visuospatial sketchpad (visuospatial span) and the central executive (working memory span, dual task and updating process) were examined. The group comparison analysis showed impairment in the frontal group of: (i) verbal spans (P<0.03); (ii) with a deficit of the rehearsal process (P=0.006); (iii) visuospatial span (P=0.04); (iv) working memory span (P=0.001) that disappeared after controlling for verbal span and (v) running memory (P=0.05) unrelated to updating conditions. The clinical anatomical correlation study showed that impairment of the central executive depended on frontal and posterior lesion. Cognitive dysexecutive disorders were observed in 11/20 patients with central executive deficit and an inverse dissociation was observed in two patients. Receiver operating characteristic curve analysis indicated that cognitive dysexecutive disorders had the highest ability to discriminate frontal lesions (area under curve=0.844, 95% confidence interval: 0.74-0.95; P=0.0001; central executive impairment: area under curve=0.732, 95% confidence interval: 0.57-0.82; P=0.006). This study reveals that frontal lesions induce mild impairment of short-term memory associated with a deficit of the rehearsal process supporting the role of the frontal lobe in this process; the central executive depends on lesions in the frontal lobe and posterior regions accounting for its low frequency and the negative results of group studies. Finally, the frontal dysexecutive syndrome cannot be attributed to central executive impairment, although it may contribute to some dysexecutive disorders.

  13. Expanding the mind's workspace: training and transfer effects with a complex working memory span task.

    PubMed

    Chein, Jason M; Morrison, Alexandra B

    2010-04-01

    In the present study, a novel working memory (WM) training paradigm was used to test the malleability of WM capacity and to determine the extent to which the benefits of this training could be transferred to other cognitive skills. Training involved verbal and spatial versions of a complex WM span task designed to emphasize simultaneous storage and processing requirements. Participants who completed 4 weeks of WM training demonstrated significant improvements on measures of temporary memory. These WM training benefits generalized to performance on the Stroop task and, in a novel finding, promoted significant increases in reading comprehension. The results are discussed in relation to the hypothesis that WM training affects domain-general attention control mechanisms and can thereby elicit far-reaching cognitive benefits. Implications include the use of WM training as a general tool for enhancing important cognitive skills.

  14. Task-level robot programming: Integral part of evolution from teleoperation to autonomy

    NASA Technical Reports Server (NTRS)

    Reynolds, James C.

    1987-01-01

    An explanation is presented of task-level robot programming and of how it differs from the usual interpretation of task planning for robotics. Most importantly, it is argued that the physical and mathematical basis of task-level robot programming provides inherently greater reliability than efforts to apply better known concepts from artificial intelligence (AI) to autonomous robotics. Finally, an architecture is presented that allows the integration of task-level robot programming within an evolutionary, redundant, and multi-modal framework that spans teleoperation to autonomy.

  15. 78 FR 18481 - Drawbridge Operation Regulations; Inner Harbor Navigation Canal, LA

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-03-27

    ... regulation governing the operation of the US 90 (Danzinger) vertical lift span drawbridge across the Inner... Lift Span Bridge across the Inner Harbor Navigation Canal, mile 3.10 at New Orleans, Orleans Parish...

  16. Working memory costs of task switching.

    PubMed

    Liefooghe, Baptist; Barrouillet, Pierre; Vandierendonck, André; Camos, Valérie

    2008-05-01

    Although many accounts of task switching emphasize the importance of working memory as a substantial source of the switch cost, there is a lack of evidence demonstrating that task switching actually places additional demands on working memory. The present study addressed this issue by implementing task switching in continuous complex span tasks with strictly controlled time parameters. A series of 4 experiments demonstrate that recall performance decreased as a function of the number of task switches and that the concurrent load of item maintenance had no influence on task switching. These results indicate that task switching induces a cost on working memory functioning. Implications for theories of task switching, working memory, and resource sharing are addressed.

  17. Effects of emotional content on working memory capacity.

    PubMed

    Garrison, Katie E; Schmeichel, Brandon J

    2018-02-13

    Emotional events tend to be remembered better than neutral events, but emotional states and stimuli may also interfere with cognitive processes that underlie memory performance. The current study investigated the effects of emotional content on working memory capacity (WMC), which involves both short term storage and executive attention control. We tested competing hypotheses in a preregistered experiment (N = 297). The emotional enhancement hypothesis predicts that emotional stimuli attract attention and additional processing resources relative to neutral stimuli, thereby making it easier to encode and store emotional information in WMC. The emotional impairment hypothesis, by contrast, predicts that emotional stimuli interfere with attention control and the active maintenance of information in working memory. Participants completed a common measure of WMC (the operation span task; Turner, M. L., & Engle, R. W. [1989]. Is working memory capacity task dependent? Journal of Memory and Language, 28, 127-154) that included either emotional or neutral words. Results revealed that WMC was reduced for emotional words relative to neutral words, consistent with the emotional impairment hypothesis.

  18. Neural dissociation of phonological and visual attention span disorders in developmental dyslexia: FMRI evidence from two case reports.

    PubMed

    Peyrin, C; Lallier, M; Démonet, J F; Pernet, C; Baciu, M; Le Bas, J F; Valdois, S

    2012-03-01

    A dissociation between phonological and visual attention (VA) span disorders has been reported in dyslexic children. This study investigates whether this cognitively-based dissociation has a neurobiological counterpart through the investigation of two cases of developmental dyslexia. LL showed a phonological disorder but preserved VA span whereas FG exhibited the reverse pattern. During a phonological rhyme judgement task, LL showed decreased activation of the left inferior frontal gyrus whereas this region was activated at the level of the controls in FG. Conversely, during a visual categorization task, FG demonstrated decreased activation of the parietal lobules whereas these regions were activated in LL as in the controls. These contrasted patterns of brain activation thus mirror the cognitive disorders' dissociation. These findings provide the first evidence for an association between distinct brain mechanisms and distinct cognitive deficits in developmental dyslexia, emphasizing the importance of taking into account the heterogeneity of the reading disorder. Copyright © 2012 Elsevier Inc. All rights reserved.

  19. Long-term effects of executive process training in young and old adults.

    PubMed

    Sandberg, Petra; Stigsdotter Neely, Anna

    2016-10-01

    Prior studies have examined the magnitude of training and transfer effects after process-based training in early and late adulthood. However, little is known about how long-lasting these effects are. Here we investigate the degree of stability of training gains and transfer effects in younger and older adults 18 months after completion of executive process training, tapping updating, inhibition, and shifting. From the original sample, 24 out of 30 older participants, and 19 out of 29 young adults, returned for follow-up assessment at which the criterion and transfer tests from pre- and post-test were re-administered. The results demonstrated stability of training gains in the updating criterion task (Letter Memory Running Span), and in a near transfer updating task (Number Memory Running Span) for both age groups. The young adults improved performance in two complex working memory tasks immediately after training. These transfer effects did not survive across time. Our results provide evidence that executive process training has its greatest effect on transfer tasks with a substantial process overlap with the trained tasks: only those effects are maintained over an 18 month period in both early and late adulthood.

  20. Working Memory Training and Speech in Noise Comprehension in Older Adults.

    PubMed

    Wayne, Rachel V; Hamilton, Cheryl; Jones Huyck, Julia; Johnsrude, Ingrid S

    2016-01-01

    Understanding speech in the presence of background sound can be challenging for older adults. Speech comprehension in noise appears to depend on working memory and executive-control processes (e.g., Heald and Nusbaum, 2014), and their augmentation through training may have rehabilitative potential for age-related hearing loss. We examined the efficacy of adaptive working-memory training (Cogmed; Klingberg et al., 2002) in 24 older adults, assessing generalization to other working-memory tasks (near-transfer) and to other cognitive domains (far-transfer) using a cognitive test battery, including the Reading Span test, sensitive to working memory (e.g., Daneman and Carpenter, 1980). We also assessed far transfer to speech-in-noise performance, including a closed-set sentence task (Kidd et al., 2008). To examine the effect of cognitive training on benefit obtained from semantic context, we also assessed transfer to open-set sentences; half were semantically coherent (high-context) and half were semantically anomalous (low-context). Subjects completed 25 sessions (0.5-1 h each; 5 sessions/week) of both adaptive working memory training and placebo training over 10 weeks in a crossover design. Subjects' scores on the adaptive working-memory training tasks improved as a result of training. However, training did not transfer to other working memory tasks, nor to tasks recruiting other cognitive domains. We did not observe any training-related improvement in speech-in-noise performance. Measures of working memory correlated with the intelligibility of low-context, but not high-context, sentences, suggesting that sentence context may reduce the load on working memory. The Reading Span test significantly correlated only with a test of visual episodic memory, suggesting that the Reading Span test is not a pure-test of working memory, as is commonly assumed.

  1. Working Memory Training and Speech in Noise Comprehension in Older Adults

    PubMed Central

    Wayne, Rachel V.; Hamilton, Cheryl; Jones Huyck, Julia; Johnsrude, Ingrid S.

    2016-01-01

    Understanding speech in the presence of background sound can be challenging for older adults. Speech comprehension in noise appears to depend on working memory and executive-control processes (e.g., Heald and Nusbaum, 2014), and their augmentation through training may have rehabilitative potential for age-related hearing loss. We examined the efficacy of adaptive working-memory training (Cogmed; Klingberg et al., 2002) in 24 older adults, assessing generalization to other working-memory tasks (near-transfer) and to other cognitive domains (far-transfer) using a cognitive test battery, including the Reading Span test, sensitive to working memory (e.g., Daneman and Carpenter, 1980). We also assessed far transfer to speech-in-noise performance, including a closed-set sentence task (Kidd et al., 2008). To examine the effect of cognitive training on benefit obtained from semantic context, we also assessed transfer to open-set sentences; half were semantically coherent (high-context) and half were semantically anomalous (low-context). Subjects completed 25 sessions (0.5–1 h each; 5 sessions/week) of both adaptive working memory training and placebo training over 10 weeks in a crossover design. Subjects' scores on the adaptive working-memory training tasks improved as a result of training. However, training did not transfer to other working memory tasks, nor to tasks recruiting other cognitive domains. We did not observe any training-related improvement in speech-in-noise performance. Measures of working memory correlated with the intelligibility of low-context, but not high-context, sentences, suggesting that sentence context may reduce the load on working memory. The Reading Span test significantly correlated only with a test of visual episodic memory, suggesting that the Reading Span test is not a pure-test of working memory, as is commonly assumed. PMID:27047370

  2. Transcranial direct current stimulation can enhance working memory in Huntington's disease.

    PubMed

    Eddy, Clare M; Shapiro, Kimron; Clouter, Andrew; Hansen, Peter C; Rickards, Hugh E

    2017-07-03

    Transcranial direct current stimulation (tDCS) combined with a cognitive task can enhance targeted aspects of cognitive functioning in clinical populations. The movement disorder Huntington's disease (HD) is associated with progressive cognitive impairment. Deficits in working memory (WM) can be apparent early in the disease and impact functional capacity. We investigated whether tDCS combined with cognitive training could improve WM in patients with HD, and if baseline clinical or cognitive measures may predict efficacy. Twenty participants with HD completed this crossover trial, undergoing 1.5mA anodal tDCS over left dorsolateral prefrontal cortex and sham stimulation on separate visits. Participants and assessor were blinded to condition order, which was randomised across participants. All participants completed baseline clinical and cognitive assessments. Pre- and post-stimulation tasks included digit reordering, computerised n-back tests and a Stroop task. During 15min of tDCS/sham stimulation, participants practiced 1- and 2-back WM tasks. Participants exhibited an increase in WM span on the digit re-ordering span task from pre- to post-stimulation after tDCS, but not after sham stimulation. Gains in WM were positively related to motor symptom ratings and negatively associated with verbal fluency scores. Patients with more severe motor symptoms showed greatest improvement, suggesting that motor symptom ratings may help identify patients who are most likely to benefit from tDCS. Dorsolateral prefrontal tDCS appears well tolerated in HD and enhances WM span compared to sham stimulation. Our findings strongly encourage further investigation of the extent to which tDCS combined with cognitive training could enhance everyday function in HD. ClinicalTrials.gov; NCT02216474 Brain stimulation in Movement Disorders; https://clinicaltrials.gov/ct2/show/NCT02216474. Copyright © 2017 Elsevier Inc. All rights reserved.

  3. Creativity and working memory capacity in sports: working memory capacity is not a limiting factor in creative decision making amongst skilled performers.

    PubMed

    Furley, Philip; Memmert, Daniel

    2015-01-01

    The goal of the study was to investigate the relationship between domain-general working memory capacity and domain-specific creativity amongst experienced soccer players. We administered the automated operation span task in combination with a domain-specific soccer creativity task to a group of 61 experienced soccer players to address the question whether an athlete's domain-specific creativity is restricted by their domain-general cognitive abilities (i.e., working memory capacity). Given that previous studies have either found a positive correlation, a negative correlation, or no correlation between working memory capacity and creativity, we analyzed the data in an exploratory manner by following recent recommendations to report effect-size estimations and their precision in form of 95% confidence intervals. The pattern of results provided evidence that domain-general working memory capacity is not associated with creativity in a soccer-specific creativity task. This pattern of results suggests that future research and theorizing on the role of working memory in everyday creative performance needs to distinguish between different types of creative performance while also taking the role of domain-specific experience into account.

  4. Creativity and working memory capacity in sports: working memory capacity is not a limiting factor in creative decision making amongst skilled performers

    PubMed Central

    Furley, Philip; Memmert, Daniel

    2015-01-01

    The goal of the study was to investigate the relationship between domain-general working memory capacity and domain-specific creativity amongst experienced soccer players. We administered the automated operation span task in combination with a domain-specific soccer creativity task to a group of 61 experienced soccer players to address the question whether an athlete’s domain-specific creativity is restricted by their domain-general cognitive abilities (i.e., working memory capacity). Given that previous studies have either found a positive correlation, a negative correlation, or no correlation between working memory capacity and creativity, we analyzed the data in an exploratory manner by following recent recommendations to report effect-size estimations and their precision in form of 95% confidence intervals. The pattern of results provided evidence that domain-general working memory capacity is not associated with creativity in a soccer-specific creativity task. This pattern of results suggests that future research and theorizing on the role of working memory in everyday creative performance needs to distinguish between different types of creative performance while also taking the role of domain-specific experience into account. PMID:25713552

  5. Electrophysiological indices of altered working memory processes in long-term ecstasy users.

    PubMed

    Nulsen, Claire; Fox, Allison; Hammond, Geoff

    2011-10-01

    The aim of this study was to determine the effect of light long-term ecstasy consumption on verbal short-term and working memory and to identify the cognitive processes contributing to task performance. Electroencephalogram was recorded while ecstasy users (N = 11), polydrug users (N = 13), and non-users (N = 13) completed forward and backward serial recognition tasks designed to engage verbal short-term memory and verbal working memory, respectively. All three groups displayed significantly lower digit-backward span than digit-forward span with ecstasy users displaying the greatest difference. The parietally distributed P3b was significantly smaller in the digits backward task than in the digits forward task in non-ecstasy-using controls. Ecstasy users did not show the reduced P3b component in the backward task that was seen in both non-ecstasy-using control groups. Ecstasy users' performance was suppressed more by the concurrent processing demands of the working memory task than that of the non-ecstasy-using controls. Non-ecstasy-using controls showed differential event-related potential wave forms in the short-term and working memory tasks, and this pattern was not seen in the ecstasy users. This is consistent with a reduction in the cognitive resources allocated to processing in working memory in ecstasy users. Copyright © 2011 John Wiley & Sons, Ltd.

  6. Influence of pharmacological manipulations of NMDA and cholinergic receptors on working versus reference memory in a dual component odor span task.

    PubMed

    MacQueen, David A; Dalrymple, Savannah R; Drobes, David J; Diamond, David M

    2016-06-01

    Developed as a tool to assess working memory capacity in rodents, the odor span task (OST) has significant potential to advance drug discovery in animal models of psychiatric disorders. Prior investigations indicate OST performance is impaired by systemic administration of N-methyl-d-aspartate receptor (NMDA-r) antagonists and is sensitive to cholinergic manipulations. The present study sought to determine whether an impairment in OST performance can be produced by systemic administration of the competitive NMDA-r antagonist 3-(2-carboxypiperazin-4-yl)propyl-1-phosphonic acid (CPP; 3, 10, 17 mg/kg i.p.) in a unique dual-component variant of the OST, and whether this impairment is ameliorated by nicotine (0.75 mg/kg i.p.). Male Sprague-Dawley rats were trained to asymptotic level of performance on a 24-trial two-comparison incrementing nonmatching to sample OST. In addition, rats were administered a two-comparison olfactory reference memory (RM) task, which was integrated into the OST. The RM task provided an assessment of the effects of drug administration on global behavioral measures, long-term memory and motivation. Several measures of working memory (span, longest run, and accuracy) were dose dependently impaired by CPP without adversely affecting RM. Analysis of drug effects across trial blocks demonstrated a significant impairment of performance even at low memory loads, suggesting a CPP-induced deficit of olfactory short-term memory that is not load-dependent. Although nicotine did not ameliorate CPP-induced impairments in span or accuracy, it did block the impairment in longest run produced by the 10 mg/kg dose of CPP. Overall, our results indicate that performance in our 24 odor two-comparison OST is capacity dependent and that CPP impaired OST working, but not reference, memory. © 2016 MacQueen et al.; Published by Cold Spring Harbor Laboratory Press.

  7. Management of the Space Physics Analysis Network (SPAN)

    NASA Technical Reports Server (NTRS)

    Green, James L.; Thomas, Valerie L.; Butler, Todd F.; Peters, David J.; Sisson, Patricia L.

    1990-01-01

    Here, the purpose is to define the operational management structure and to delineate the responsibilities of key Space Physics Analysis Network (SPAN) individuals. The management structure must take into account the large NASA and ESA science research community by giving them a major voice in the operation of the system. Appropriate NASA and ESA interfaces must be provided so that there will be adequate communications facilities available when needed. Responsibilities are delineated for the Advisory Committee, the Steering Committee, the Project Scientist, the Project Manager, the SPAN Security Manager, the Internetwork Manager, the Network Operations Manager, the Remote Site Manager, and others.

  8. Executive Function: Comparing Bilingual and Monolingual Iranian University Students

    ERIC Educational Resources Information Center

    Kazemeini, Toktam; Fadardi, Javad Salehi

    2016-01-01

    The study aimed to examine whether Kurdish-Persian early Bilingual university students (EBL) and Persian Monolingual university students (ML) differ on tasks of executive function (EF). Thirty male EBL and 30 male ML students from Ferdowsi University of Mashhad completed a Persian Stroop Color-Word task (SCWT), Backward Digit Span Test (BDST),…

  9. The Influence of Domain Knowledge on the Functional Capacity of Working Memory

    ERIC Educational Resources Information Center

    Ricks, Travis Rex; Wiley, Jennifer

    2009-01-01

    Theories of expertise have proposed that superior cognitive performance is in part due to increases in the functional capacity of working memory during domain-related tasks. Consistent with this approach Fincher-Kiefer et al. (1988), found that domain knowledge increased scores on baseball-related reading span tasks. The present studies extended…

  10. Cognitive Tasks as Predictors of Behavioral Competencies in the Aged.

    ERIC Educational Resources Information Center

    Cyr, J.; Stones, M. J.

    This paper discusses the quantitative and qualitative aspects of the relationship between cognitive abilities and behavioral competencies in elderly institutional residents. The former was assessed by an array of five cognitive measures: two Piagetian tasks, Set Test, WAIS Vocabulary and Digit Span subtests, and the WMS Associate Learning subtest;…

  11. Integrated and Independent Learning of Hand-Related Constituent Sequences

    ERIC Educational Resources Information Center

    Berner, Michael P.; Hoffmann, Joachim

    2009-01-01

    In almost all daily activities fingers of both hands are used in coordinated succession. The present experiments explored whether learning in such tasks pertains not only to the overall sequence spanning both hands but also to the constituent sequences of each hand. In a serial reaction time task, 2 repeating hand-related sequences were…

  12. Contribution of reactive and proactive control to children's working memory performance: Insight from item recall durations in response sequence planning.

    PubMed

    Chevalier, Nicolas; James, Tiffany D; Wiebe, Sandra A; Nelson, Jennifer Mize; Espy, Kimberly Andrews

    2014-07-01

    The present study addressed whether developmental improvement in working memory span task performance relies upon a growing ability to proactively plan response sequences during childhood. Two hundred thirteen children completed a working memory span task in which they used a touchscreen to reproduce orally presented sequences of animal names. Children were assessed longitudinally at 7 time points between 3 and 10 years of age. Twenty-one young adults also completed the same task. Proactive response sequence planning was assessed by comparing recall durations for the 1st item (preparatory interval) and subsequent items. At preschool age, the preparatory interval was generally shorter than subsequent item recall durations, whereas it was systematically longer during elementary school and in adults. Although children mostly approached the task reactively at preschool, they proactively planned response sequences with increasing efficiency from age 7 on, like adults. These findings clarify the nature of the changes in executive control that support working memory performance with age. (PsycINFO Database Record (c) 2014 APA, all rights reserved).

  13. Integrating planning and reactive control

    NASA Technical Reports Server (NTRS)

    Wilkins, David E.; Myers, Karen L.

    1994-01-01

    Our research is developing persistent agents that can achieve complex tasks in dynamic and uncertain environments. We refer to such agents as taskable, reactive agents. An agent of this type requires a number of capabilities. The ability to execute complex tasks necessitates the use of strategic plans for accomplishing tasks; hence, the agent must be able to synthesize new plans at run time. The dynamic nature of the environment requires that the agent be able to deal with unpredictable changes in its world. As such, agents must be able to react to unanticipated events by taking appropriate actions in a timely manner, while continuing activities that support current goals. The unpredictability of the world could lead to failure of plans generated for individual tasks. Agents must have the ability to recover from failures by adapting their activities to the new situation, or replanning if the world changes sufficiently. Finally, the agent should be able to perform in the face of uncertainty. The Cypress system, described here, provides a framework for creating taskable, reactive agents. Several features distinguish our approach: (1) the generation and execution of complex plans with parallel actions; (2) the integration of goal-driven and event driven activities during execution; (3) the use of evidential reasoning for dealing with uncertainty; and (4) the use of replanning to handle run-time execution problems. Our model for a taskable, reactive agent has two main intelligent components, an executor and a planner. The two components share a library of possible actions that the system can take. The library encompasses a full range of action representations, including plans, planning operators, and executable procedures such as predefined standard operating procedures (SOP's). These three classes of actions span multiple levels of abstraction.

  14. Integrating planning and reactive control

    NASA Astrophysics Data System (ADS)

    Wilkins, David E.; Myers, Karen L.

    1994-10-01

    Our research is developing persistent agents that can achieve complex tasks in dynamic and uncertain environments. We refer to such agents as taskable, reactive agents. An agent of this type requires a number of capabilities. The ability to execute complex tasks necessitates the use of strategic plans for accomplishing tasks; hence, the agent must be able to synthesize new plans at run time. The dynamic nature of the environment requires that the agent be able to deal with unpredictable changes in its world. As such, agents must be able to react to unanticipated events by taking appropriate actions in a timely manner, while continuing activities that support current goals. The unpredictability of the world could lead to failure of plans generated for individual tasks. Agents must have the ability to recover from failures by adapting their activities to the new situation, or replanning if the world changes sufficiently. Finally, the agent should be able to perform in the face of uncertainty. The Cypress system, described here, provides a framework for creating taskable, reactive agents. Several features distinguish our approach: (1) the generation and execution of complex plans with parallel actions; (2) the integration of goal-driven and event driven activities during execution; (3) the use of evidential reasoning for dealing with uncertainty; and (4) the use of replanning to handle run-time execution problems. Our model for a taskable, reactive agent has two main intelligent components, an executor and a planner. The two components share a library of possible actions that the system can take. The library encompasses a full range of action representations, including plans, planning operators, and executable procedures such as predefined standard operating procedures (SOP's). These three classes of actions span multiple levels of abstraction.

  15. Foraging across the life span: is there a reduction in exploration with aging?

    PubMed Central

    Mata, Rui; Wilke, Andreas; Czienskowski, Uwe

    2013-01-01

    Does foraging change across the life span, and in particular, with aging? We report data from two foraging tasks used to investigate age differences in search in external environments as well as internal search in memory. Overall, the evidence suggests that foraging behavior may undergo significant changes across the life span across internal and external search. In particular, we find evidence of a trend toward reduced exploration with increased age. We discuss these findings in light of theories that postulate a link between aging and reductions in novelty seeking and exploratory behavior. PMID:23616741

  16. Gait performance is not influenced by working memory when walking at a self-selected pace.

    PubMed

    Grubaugh, Jordan; Rhea, Christopher K

    2014-02-01

    Gait performance exhibits patterns within the stride-to-stride variability that can be indexed using detrended fluctuation analysis (DFA). Previous work employing DFA has shown that gait patterns can be influenced by constraints, such as natural aging or disease, and they are informative regarding a person's functional ability. Many activities of daily living require concurrent performance in the cognitive and gait domains; specifically working memory is commonly engaged while walking, which is considered dual-tasking. It is unknown if taxing working memory while walking influences gait performance as assessed by DFA. This study used a dual-tasking paradigm to determine if performance decrements are observed in gait or working memory when performed concurrently. Healthy young participants (N = 16) performed a working memory task (automated operation span task) and a gait task (walking at a self-selected speed on a treadmill) in single- and dual-task conditions. A second dual-task condition (reading while walking) was included to control for visual attention, but also introduced a task that taxed working memory over the long term. All trials involving gait lasted at least 10 min. Performance in the working memory task was indexed using five dependent variables (absolute score, partial score, speed error, accuracy error, and math error), while gait performance was indexed by quantifying the mean, standard deviation, and DFA α of the stride interval time series. Two multivariate analyses of variance (one for gait and one for working memory) were used to examine performance in the single- and dual-task conditions. No differences were observed in any of the gait or working memory dependent variables as a function of task condition. The results suggest the locomotor system is adaptive enough to complete a working memory task without compromising gait performance when walking at a self-selected pace.

  17. 76 FR 26606 - Drawbridge Operation Regulation; Illinois Waterway, Near Morris, IL

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-05-09

    ... allow removal of the existing lift span and installation of the replacement lift span. This deviation...-navigation position for eighty-four hours while the existing lift span is removed and the replacement lift...

  18. Human Factors in Training

    NASA Technical Reports Server (NTRS)

    Barshi, Immanuel; Byme, Vicky; Arsintescu, Lucia

    2008-01-01

    Future space missions will be significantly longer than current Shuttle missions and new systems will be more complex than current systems. Increasing communication delays between crews and Earth-based support means that astronauts need to be prepared to handle the unexpected on their own. As crews become more autonomous, their potential span of control and required expertise must grow to match their autonomy. It is not possible to train for every eventuality ahead of time on the ground, or to maintain trained skills across long intervals of disuse. To adequately prepare NASA personnel for these challenges, new training approaches, methodologies, and tools are required. This research project aims at developing these training capabilities. Training efforts in FY07 strongly focused on crew medical training, but also began exploring how Space Flight Resource Management training for Mission Operations Directorate (MOD) Flight Controllers could be integrated with systems training for optimal Mission Control Center operations. Beginning in January 2008, the training research effort will include team training prototypes and tools. The Training Task addresses Program risks that lie at the intersection of the following three risks identified by the Project: 1) Risk associated with poor task design; 2) Risk of error due to inadequate information; 3) Risk associated with reduced safety and efficiency due to poor human factors design.

  19. The Effect of Orthographic Depth on Letter String Processing: The Case of Visual Attention Span and Rapid Automatized Naming

    ERIC Educational Resources Information Center

    Antzaka, Alexia; Martin, Clara; Caffarra, Sendy; Schlöffel, Sophie; Carreiras, Manuel; Lallier, Marie

    2018-01-01

    The present study investigated whether orthographic depth can increase the bias towards multi-letter processing in two reading-related skills: visual attention span (VAS) and rapid automatized naming (RAN). VAS (i.e., the number of visual elements that can be processed at once in a multi-element array) was tested with a visual 1-back task and RAN…

  20. 77 FR 24147 - Drawbridge Operation Regulation; Mile 359.4, Missouri River, Kansas City, MO

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-04-23

    ... eight wire rope lifting cables that operate the lift span. This deviation allows the bridge to remain in the closed position while the lift cables are replaced. DATES: This deviation is effective from 10 p.m... cables that operate the lift span are replaced. The closure period will start at 10 p.m. on or about May...

  1. 77 FR 28488 - Drawbridge Operation Regulation; Upper Mississippi River, Hannibal, MO

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-05-15

    ... lifting cables that operate the lift span. This deviation allows the bridge to remain in the closed position while the lift cables are replaced. DATES: This deviation is effective from 9 a.m. to 3 p.m. on or... wire rope lifting cables that operate the lift span are replaced. The closure period will be from 9 a.m...

  2. Working memory recall precision is a more sensitive index than span.

    PubMed

    Zokaei, Nahid; Burnett Heyes, Stephanie; Gorgoraptis, Nikos; Budhdeo, Sanjay; Husain, Masud

    2015-09-01

    Delayed adjustment tasks have recently been developed to examine working memory (WM) precision, that is, the resolution with which items maintained in memory are recalled. However, despite their emerging use in experimental studies of healthy people, evaluation of patient populations is sparse. We first investigated the validity of adjustment tasks, comparing precision with classical span measures of memory across the lifespan in 114 people. Second, we asked whether precision measures can potentially provide a more sensitive measure of WM than traditional span measures. Specifically, we tested this hypothesis examining WM in a group with early, untreated Parkinson's disease (PD) and its modulation by subsequent treatment on dopaminergic medication. Span measures correlated with precision across the lifespan: in children, young, and elderly participants. However, they failed to detect changes in WM in PD patients, either pre- or post-treatment initiation. By contrast, recall precision was sensitive enough to pick up such changes. PD patients pre-medication were significantly impaired compared to controls, but improved significantly after 3 months of being established on dopaminergic medication. These findings suggest that precision methods might provide a sensitive means to investigate WM and its modulation by interventions in clinical populations. © 2014 The Authors Journal of Neuropsychology published by John Wiley & Sons Ltd on behalf of British Psychological Society.

  3. Time and resource limits on working memory: cross-age consistency in counting span performance.

    PubMed

    Ransdell, Sarah; Hecht, Steven

    2003-12-01

    This longitudinal study separated resource demand effects from those of retention interval in a counting span task among 100 children tested in grade 2 and again in grades 3 and 4. A last card large counting span condition had an equivalent memory load to a last card small, but the last card large required holding the count over a longer retention interval. In all three waves of assessment, the last card large condition was found to be less accurate than the last card small. A model predicting reading comprehension showed that age was a significant predictor when entered first accounting for 26% of the variance, but counting span accounted for a further 22% of the variance. Span at Wave 1 accounted for significant unique variance at Wave 2 and at Wave 3. Results were similar for math calculation with age accounting for 31% of the variance and counting span accounting for a further 34% of the variance. Span at Wave 1 explained unique variance in math at Wave 2 and at Wave 3.

  4. Revision of XLM-2013-1129 as invited by the Action Editor, Rebekah Smith

    PubMed Central

    Naveh-Benjamin, Moshe; Kilb, Angela; Maddox, Geoff; Thomas, Jenna; Fine, Hope; Chen, Tina; Cowan, Nelson

    2014-01-01

    Although older adults have lower working memory spans on average than young adults, we demonstrate in five experiments one way in which older adults paradoxically resemble higher-capacity young adults. Specifically, in a selective-listening task, older adults almost always failed to notice their names presented in an unattended channel. This is an exaggeration of what high-span young adults show, and the opposite of what low spans show. This striking finding in older adults remained significant after controlling for working memory span and for noticing their names in an attended channel. The findings were replicated when presentation rate was made slower and when the ear in which the unattended name was presented was controlled. These results point to an account of older adults’ performance involving not only an inhibition factor, which allows high-span young adults to suppress the channel to be ignored, but also an attentional capacity factor, with more unallocated capacity allowing low-span young adults to notice their names much more often than older adults with comparably low spans. PMID:24820668

  5. Learning to Mow Grass: IDF Adaptations to Hybrid Threats

    DTIC Science & Technology

    2017-05-25

    lie on a spectrum from tactical techniques to wholesale paradigm shift.7 This study examines military adaptations in the case of the Israeli Defense...against the hybrid threat in three case studies spanning the Second Lebanon War in 2006, Operation Cast Lead in 2008, and Operation Protective Edge in...hybrid threat in three case studies spanning the Second Lebanon War in 2006, Operation Cast Lead in 2008, and Operation Protective Edge in 2014. The

  6. Resting-State Network Topology Differentiates Task Signals across the Adult Life Span.

    PubMed

    Chan, Micaela Y; Alhazmi, Fahd H; Park, Denise C; Savalia, Neil K; Wig, Gagan S

    2017-03-08

    Brain network connectivity differs across individuals. For example, older adults exhibit less segregated resting-state subnetworks relative to younger adults (Chan et al., 2014). It has been hypothesized that individual differences in network connectivity impact the recruitment of brain areas during task execution. While recent studies have described the spatial overlap between resting-state functional correlation (RSFC) subnetworks and task-evoked activity, it is unclear whether individual variations in the connectivity pattern of a brain area (topology) relates to its activity during task execution. We report data from 238 cognitively normal participants (humans), sampled across the adult life span (20-89 years), to reveal that RSFC-based network organization systematically relates to the recruitment of brain areas across two functionally distinct tasks (visual and semantic). The functional activity of brain areas (network nodes) were characterized according to their patterns of RSFC: nodes with relatively greater connections to nodes in their own functional system ("non-connector" nodes) exhibited greater activity than nodes with relatively greater connections to nodes in other systems ("connector" nodes). This "activation selectivity" was specific to those brain systems that were central to each of the tasks. Increasing age was accompanied by less differentiated network topology and a corresponding reduction in activation selectivity (or differentiation) across relevant network nodes. The results provide evidence that connectional topology of brain areas quantified at rest relates to the functional activity of those areas during task. Based on these findings, we propose a novel network-based theory for previous reports of the "dedifferentiation" in brain activity observed in aging. SIGNIFICANCE STATEMENT Similar to other real-world networks, the organization of brain networks impacts their function. As brain network connectivity patterns differ across individuals, we hypothesized that individual differences in network connectivity would relate to differences in brain activity. Using functional MRI in a group of individuals sampled across the adult life span (20-89 years), we measured correlations at rest and related the functional connectivity patterns to measurements of functional activity during two independent tasks. Brain activity varied in relation to connectivity patterns revealed by large-scale network analysis. This relationship tracked the differences in connectivity patterns accompanied by older age, providing important evidence for a link between the topology of areal connectivity measured at rest and the functional recruitment of these areas during task performance. Copyright © 2017 Chan et al.

  7. Cognitive Control and Language across the Life Span: Does Labeling Improve Reactive Control?

    ERIC Educational Resources Information Center

    Lucenet, Joanna; Blaye, Agnès; Chevalier, Nicolas; Kray, Jutta

    2014-01-01

    How does cognitive control change with age, and what are the processes underlying these changes? This question has been extensively studied using versions of the task-switching paradigm, which allow participants to actively prepare for the upcoming task (Kray, Eber, & Karbach, 2008). Little is known, however, about age-related changes in this…

  8. Working Memory Training Does Not Improve Intelligence in Healthy Young Adults

    ERIC Educational Resources Information Center

    Chooi, Weng-Tink; Thompson, Lee A.

    2012-01-01

    Jaeggi and her colleagues claimed that they were able to improve fluid intelligence by training working memory. Subjects who trained their working memory on a dual n-back task for a period of time showed significant improvements in working memory span tasks and fluid intelligence tests such as the Raven's Progressive Matrices and the Bochumer…

  9. Investigating Sentence Processing and Language Segmentation in Explaining Children's Performance on a Sentence-Span Task

    ERIC Educational Resources Information Center

    Mainela-Arnold, Elina; Misra, Maya; Miller, Carol; Poll, Gerard H.; Park, Ji Sook

    2012-01-01

    Background: Children with poor language abilities tend to perform poorly on verbal working memory tasks. This result has been interpreted as evidence that limitations in working memory capacity may interfere with the development of a mature linguistic system. However, it is possible that language abilities, such as the efficiency of sentence…

  10. Response Inhibition and Its Relationship to Phonological Processing in Children with and without Dyslexia

    ERIC Educational Resources Information Center

    Schmid, Johanna M.; Labuhn, Andju S.; Hasselhorn, Marcus

    2011-01-01

    This study investigates response inhibition and its relationship to phonological processing in third-graders with and without dyslexia. Children with dyslexia (n = 20) and children without dyslexia (n = 16) were administered a stop signal task and a digit span forwards task. Initial analyses revealed phonological processing deficits in terms of a…

  11. 77 FR 19937 - Drawbridge Operation Regulation; Mile 21.6, Illinois Waterway, Hardin, IL

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-04-03

    ..., Illinois. The deviation is necessary to replace the main gear case that operates the lift span. The gear... end at 7 p.m. on April 5, 2012. Once the existing gear case is removed, the lift span will not be able...

  12. 75 FR 76279 - Drawbridge Operation Regulation; Upper Mississippi River, Burlington, IA

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-12-08

    ... bridge owner time to replace the swing span with a lift span and to construct the right descending tower... the Truman-Hobbs alteration. The new lift span will be set in place and the right descending tower...

  13. The impact of instructional context on classroom on-task behavior: a matched comparison of children with ADHD and non-ADHD classmates.

    PubMed

    Imeraj, Lindita; Antrop, Inge; Sonuga-Barke, Edmund; Deboutte, Dirk; Deschepper, Ellen; Bal, Sarah; Roeyers, Herbert

    2013-08-01

    Classroom inattentiveness is an important reason for clinical referral of children with ADHD and a strong predictor of their educational achievement. This study investigates classroom on-task behavior of Flemish children with ADHD withdrawn from medication as a function of instructional context. Thirty-one pairs of children (one with ADHD and one age- and sex-matched control; 25 boys and 6 girls 6 to 12years of age) were observed in their classroom environment during two consecutive school days. On-task behavior (time on-task and on-task span) of ADHD and non-ADHD individuals was compared in different class contexts (i.e., different class structures and academic content types). Individualized teacher supervision was simultaneously assessed. Generalized estimation equation analyses showed that children with ADHD were significantly less on-task than controls during individual work and whole class group teaching, but not during small group work, and had significantly shorter on-task span during academic tasks (mathematics, language, and sciences) and instructional transitions between tasks, but not during music and arts. These effects persisted even after controlling for the higher levels of teacher supervision observed for ADHD pupils (7%) across all contexts (vs. 4% in controls). Findings suggest that despite receiving more overall teacher supervision, children with ADHD displayed lower levels of on-task behavior in settings that place high self-regulatory, information processing, and motivational demands on them. This finding may have initial implications for classroom interventions in this population. Copyright © 2013 Society for the Study of School Psychology. Published by Elsevier Ltd. All rights reserved. Published by Elsevier Ltd. All rights reserved.

  14. A Virtual Object-Location Task for Children: Gender and Videogame Experience Influence Navigation; Age Impacts Memory and Completion Time.

    PubMed

    Rodriguez-Andres, David; Mendez-Lopez, Magdalena; Juan, M-Carmen; Perez-Hernandez, Elena

    2018-01-01

    The use of virtual reality-based tasks for studying memory has increased considerably. Most of the studies that have looked at child population factors that influence performance on such tasks have been focused on cognitive variables. However, little attention has been paid to the impact of non-cognitive skills. In the present paper, we tested 52 typically-developing children aged 5-12 years in a virtual object-location task. The task assessed their spatial short-term memory for the location of three objects in a virtual city. The virtual task environment was presented using a 3D application consisting of a 120″ stereoscopic screen and a gamepad interface. Measures of learning and displacement indicators in the virtual environment, 3D perception, satisfaction, and usability were obtained. We assessed the children's videogame experience, their visuospatial span, their ability to build blocks, and emotional and behavioral outcomes. The results indicate that learning improved with age. Significant effects on the speed of navigation were found favoring boys and those more experienced with videogames. Visuospatial skills correlated mainly with ability to recall object positions, but the correlation was weak. Longer paths were related with higher scores of withdrawal behavior, attention problems, and a lower visuospatial span. Aggressiveness and experience with the device used for interaction were related with faster navigation. However, the correlations indicated only weak associations among these variables.

  15. Individual differences in learning and transfer: stable tendencies for learning exemplars versus abstracting rules.

    PubMed

    McDaniel, Mark A; Cahill, Michael J; Robbins, Mathew; Wiener, Chelsea

    2014-04-01

    We hypothesize that during training some learners may focus on acquiring the particular exemplars and responses associated with the exemplars (termed exemplar learners), whereas other learners attempt to abstract underlying regularities reflected in the particular exemplars linked to an appropriate response (termed rule learners). Supporting this distinction, after training (on a function-learning task), participants displayed an extrapolation profile reflecting either acquisition of the trained cue-criterion associations (exemplar learners) or abstraction of the function rule (rule learners; Studies 1a and 1b). Further, working memory capacity (measured by operation span [Ospan]) was associated with the tendency to rely on rule versus exemplar processes. Studies 1c and 2 examined the persistence of these learning tendencies on several categorization tasks. Study 1c showed that rule learners were more likely than exemplar learners (indexed a priori by extrapolation profiles) to resist using idiosyncratic features (exemplar similarity) in generalization (transfer) of the trained category. Study 2 showed that the rule learners but not the exemplar learners performed well on a novel categorization task (transfer) after training on an abstract coherent category. These patterns suggest that in complex conceptual tasks, (a) individuals tend to either focus on exemplars during learning or on extracting some abstraction of the concept, (b) this tendency might be a relatively stable characteristic of the individual, and (c) transfer patterns are determined by that tendency.

  16. The relation of saturated fats and dietary cholesterol to childhood cognitive flexibility.

    PubMed

    Khan, Naiman A; Raine, Lauren B; Drollette, Eric S; Scudder, Mark R; Hillman, Charles H

    2015-10-01

    Identification of health behaviors and markers of physiological health associated with childhood cognitive function has important implications for public health policy targeted toward cognitive health throughout the life span. Although previous studies have shown that aerobic fitness and obesity exert contrasting effects on cognitive flexibility among prepubertal children, the extent to which diet plays a role in cognitive flexibility has received little attention. Accordingly, this study examined associations between saturated fats and cholesterol intake and cognitive flexibility, assessed using a task switching paradigm, among prepubertal children between 7 and 10 years (N = 150). Following adjustment of confounding variables (age, sex, socioeconomic status, IQ, VO2max, and BMI), children consuming diets higher in saturated fats exhibited longer reaction time during the task condition requiring greater amounts of cognitive flexibility. Further, increasing saturated fat intake and dietary cholesterol were correlated with greater switch costs, reflecting impaired ability to maintain multiple task sets in working memory and poorer efficiency of cognitive control processes involved in task switching. These data are among the first to indicate that children consuming diets higher in saturated fats and cholesterol exhibit compromised ability to flexibly modulate their cognitive operations, particularly when faced with greater cognitive challenge. Future longitudinal and intervention studies are necessary to comprehensively characterize the interrelationships between diet, aerobic fitness, obesity, and children's cognitive abilities. Copyright © 2015 Elsevier Ltd. All rights reserved.

  17. Effects of Working Memory Capacity on Metacognitive Monitoring: A Study of Group Differences Using a Listening Span Test.

    PubMed

    Komori, Mie

    2016-01-01

    Monitoring is an executive function of working memory that serves to update novel information, focusing attention on task-relevant targets, and eliminating task-irrelevant noise. The present research used a verbal working memory task to examine how working memory capacity limits affect monitoring. Participants performed a Japanese listening span test that included maintenance of target words and listening comprehension. On each trial, participants responded to the target word and then immediately estimated confidence in recall performance for that word (metacognitive judgment). The results confirmed significant differences in monitoring accuracy between high and low capacity groups in a multi-task situation. That is, confidence judgments were superior in high vs. low capacity participants in terms of absolute accuracy and discrimination. The present research further investigated how memory load and interference affect underestimation of successful recall. The results indicated that the level of memory load that reduced word recall performance and led to an underconfidence bias varied according to participants' memory capacity. In addition, irrelevant information associated with incorrect true/ false decisions (secondary task) and word recall within the current trial impaired monitoring accuracy in both participant groups. These findings suggest that interference from unsuccessful decisions only influences low, but not high, capacity participants. Therefore, monitoring accuracy, which requires high working memory capacity, improves metacognitive abilities by inhibiting task-irrelevant noise and focusing attention on detecting task-relevant targets or useful retrieval cues, which could improve actual cognitive performance.

  18. Reaction time inconsistency in a spatial stroop task: age-related differences through childhood and adulthood.

    PubMed

    Williams, Benjamin R; Strauss, Esther H; Hultsch, David F; Hunter, Michael A

    2007-07-01

    Age-related differences in inconsistency of reaction time (RT) across the life span were examined on a task with differing levels of demand on executive control. A total of 546 participants, aged 5 to 76 years, completed a spatial Stroop task that permitted observations under three conditions (congruent, incongruent, and neutral) according to the correspondence between the required response (based on stimulus direction) and stimulus location. An interference effect was observed across all ages. Analyses of neutral condition data replicated previous research demonstrating RT inconsistency follows a U-shaped developmental curve across the life span. The relationship between age and inconsistency, however, depended on condition: inconsistency in the congruent condition was higher than inconsistency in both the neutral and incongruent conditions across middle-aged groups. Reaction time inconsistency may reflect processing efficiency that is maximal in young adulthood and may also be sensitive to fluctuations in performance that reflect momentarily highly efficient responding.

  19. The relationship between phonological memory, receptive vocabulary, and fast mapping in young children with specific language impairment.

    PubMed

    Gray, Shelley

    2006-10-01

    This study assessed the fast mapping performance of children with specific language impairment (SLI) across the preschool to kindergarten age span in relation to their phonological memory and vocabulary development. Fifty-three children diagnosed with SLI and 53 children with normal language (NL) matched for age and gender (30 three-year-olds, 18 four-year-olds, 28 five-year-olds, and 30 six-year-olds) participated. Children's phonological memory was assessed using nonword repetition and digit span tasks. Receptive vocabulary was assessed using the Peabody Picture Vocabulary Test-III. Children learned the names for 8 objects during 2 fast mapping tasks. Overall, the NL group demonstrated significantly better performance on phonological memory and vocabulary measures across the age span; however, performance on the fast mapping task differed significantly only at age 5. Phonological memory and existing receptive vocabulary did not predict fast mapping ability. The phonological memory skills of preschoolers with NL and SLI followed a similar developmental pattern, but the SLI group consistently scored significantly lower than the NL group. Overall, the NL group showed significantly better receptive vocabulary, with evidence that between-group differences increased at age 6. Neither short-term phonological memory nor receptive vocabulary predicted fast mapping comprehension or production performance, even though both have been shown to correlate with later stages of word learning.

  20. 75 FR 55475 - Drawbridge Operation Regulation; Pequonnock River, Bridgeport, CT

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-09-13

    ... two bridges because the draw spans of the bridges have been removed. DATES: This rule is effective... removing the operation regulations for two moveable draw bridges that no longer have moveable spans. Under... litigation, eliminate ambiguity, and reduce burden. Protection of Children We have analyzed this rule under...

  1. The Contribution of Verbal Working Memory to Deaf Children’s Oral and Written Production

    PubMed Central

    Arfé, Barbara; Rossi, Cristina; Sicoli, Silvia

    2015-01-01

    This study investigated the contribution of verbal working memory to the oral and written story production of deaf children. Participants were 29 severely to profoundly deaf children aged 8–13 years and 29 hearing controls, matched for grade level. The children narrated a picture story orally and in writing and performed a reading comprehension test, the Wechsler Intelligence Scale for Children-Fourth Edition forward digit span task, and a reading span task. Oral and written stories were analyzed at the microstructural (i.e., clause) and macrostructural (discourse) levels. Hearing children’s stories scored higher than deaf children’s at both levels. Verbal working memory skills contributed to deaf children’s oral and written production over and above age and reading comprehension skills. Verbal rehearsal skills (forward digit span) contributed significantly to deaf children’s ability to organize oral and written stories at the microstructural level; they also accounted for unique variance at the macrostructural level in writing. Written story production appeared to involve greater verbal working memory resources than oral story production. PMID:25802319

  2. Development of a Semi-Span Test Capability at the National Transonic Facility

    NASA Technical Reports Server (NTRS)

    Gatlin, G. M.; Parker, P. A.; Owens, L. R., Jr.

    2001-01-01

    A need for low-speed, high Reynolds number test capabilities has been identified for the design and development of advanced subsonic transport high-lift systems. In support of this need, multiple investigations have been conducted in the National Transonic Facility (NTF) at the NASA Langley Research Center to develop a semi-span testing capability that will provide the low-speed, flight Reynolds number data currently unattainable using conventional sting-mounted, full-span models. Although a semi-span testing capability will effectively double the Reynolds number capability over full-span models, it does come at the expense of contending with the issue of the interaction of the flow over the model with the windtunnel wall boundary layer. To address this issue the size and shape of the semi-span model mounting geometry have been investigated, and the results are presented herein. The cryogenic operating environment of the NTF produced another semi-span test technique issue in that varying thermal gradients have developed on the large semi-span balance. The suspected cause of these thermal gradients and methods to eliminate them are presented. Data are also presented that demonstrate the successful elimination of these varying thermal gradients during cryogenic operations.

  3. 23 CFR 650.809 - Movable span bridges.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 23 Highways 1 2011-04-01 2011-04-01 false Movable span bridges. 650.809 Section 650.809 Highways FEDERAL HIGHWAY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION ENGINEERING AND TRAFFIC OPERATIONS BRIDGES, STRUCTURES, AND HYDRAULICS Navigational Clearances for Bridges § 650.809 Movable span bridges. A fixed bridge...

  4. 23 CFR 650.809 - Movable span bridges.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 23 Highways 1 2010-04-01 2010-04-01 false Movable span bridges. 650.809 Section 650.809 Highways FEDERAL HIGHWAY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION ENGINEERING AND TRAFFIC OPERATIONS BRIDGES, STRUCTURES, AND HYDRAULICS Navigational Clearances for Bridges § 650.809 Movable span bridges. A fixed bridge...

  5. The Development of Memory Maintenance: Children's Use of Phonological Rehearsal and Attentional Refreshment in Working Memory Tasks

    ERIC Educational Resources Information Center

    Tam, Helen; Jarrold, Christopher; Baddeley, Alan D.; Sabatos-DeVito, Maura

    2010-01-01

    Past research suggests that children begin to phonologically rehearse at around 7 years of age. Less is known regarding the development of refreshment, an attention-based maintenance mechanism. Therefore, the use of these two maintenance methods by 6- and 8-year-olds was assessed using memory span tasks that varied in their opportunities for…

  6. The Developmental Influence of Primary Memory Capacity on Working Memory and Academic Achievement

    ERIC Educational Resources Information Center

    Hall, Debbora; Jarrold, Christopher; Towse, John N.; Zarandi, Amy L.

    2015-01-01

    In this study, we investigate the development of primary memory capacity among children. Children between the ages of 5 and 8 completed 3 novel tasks (split span, interleaved lists, and a modified free-recall task) that measured primary memory by estimating the number of items in the focus of attention that could be spontaneously recalled in…

  7. The Effects of Multiple Exemplar Training on a Working Memory Task Involving Sequential Responding in Children with Autism

    ERIC Educational Resources Information Center

    Baltruschat, Lisa; Hasselhorn, Marcus; Tarbox, Jonathan; Dixon, Dennis R.; Najdowski, Adel; Mullins, Ryan David; Gould, Evelyn

    2012-01-01

    This study is part of a programmatic line of research into the use of basic positive reinforcement procedures for improving working memory in children with autism spectrum disorders. The authors evaluated the effects of multiple exemplar training, utilizing positive reinforcement, on performance of a "digit span backwards" task--a test of working…

  8. Beyond Capacity Limitations: Determinants of Word Recall Performance on Verbal Working Memory Span Tasks in Children with SLI

    ERIC Educational Resources Information Center

    Mainela-Arnold, Elina; Evans, Julia L.

    2005-01-01

    Reduced verbal working memory capacity has been proposed as a possible account of language impairments in specific language impairment (SLI). Studies have shown, however, that differences in strength of linguistic representations in the form of word frequency affect list recall and performance on verbal working memory tasks. This suggests that…

  9. Older Adults Do Not Notice Their Names: A New Twist to a Classic Attention Task

    ERIC Educational Resources Information Center

    Naveh-Benjamin, Moshe; Kilb, Angela; Maddox, Geoffrey B.; Thomas, Jenna; Fine, Hope C.; Chen, Tina; Cowan, Nelson

    2014-01-01

    Although working memory spans are, on average, lower for older adults than young adults, we demonstrate in 5 experiments a way in which older adults paradoxically resemble higher capacity young adults. Specifically, in a selective-listening task, older adults almost always failed to notice their names presented in an unattended channel. This is an…

  10. 40 CFR 60.13 - Monitoring requirements.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... operators of a CEMS installed in accordance with the provisions of this part, must check the zero (or low...) calibration drifts at least once each operating day in accordance with a written procedure. The zero and span must, at a minimum, be adjusted whenever either the 24-hour zero drift or the 24-hour span drift...

  11. Dopamine treatment and cognitive functioning in individuals with Parkinson's disease: the "cognitive flexibility" hypothesis seems to work.

    PubMed

    Costa, Alberto; Peppe, Antonella; Mazzù, Ilenia; Longarzo, Mariachiara; Caltagirone, Carlo; Carlesimo, Giovanni A

    2014-01-01

    Previous data suggest that (i) dopamine modulates the ability to implement nonroutine schemata and update operations (flexibility processes) and that (ii) dopamine-related improvement may be related to baseline dopamine levels in target pathways (inverted U-shaped hypothesis). To investigate above hypotheses in individuals with Parkinson's disease (PD). Twenty PD patients were administered tasks varying as to flexibility load in two treatment conditions: (i) "off" condition, about 18 hours after dopamine dose and (ii) "on" condition, after dopamine administration. PD patients were separated into two groups: low performers (i.e., performance on Digit Span Backward below the sample mean) and high performers (i.e., performance above the mean). Twenty healthy individuals performed the tasks in two sessions without taking drugs. Passing from the "off" to the "on" state, only low performer PD patients significantly improved their performance on high-flexibility measures (interference condition of the Stroop test; P < 0.05); no significant effect was found on low-flexibility tasks. These findings document that high-flexibility processes are sensitive to dopamine neuromodulation in the early phases of PD. This is in line with the hypothesis that striatal dopamine pathways, affected early by PD, are precociously implicated in the expression of cognitive disorders in these individuals.

  12. Short-term Memory in Childhood Dyslexia: Deficient Serial Order in Multiple Modalities.

    PubMed

    Cowan, Nelson; Hogan, Tiffany P; Alt, Mary; Green, Samuel; Cabbage, Kathryn L; Brinkley, Shara; Gray, Shelley

    2017-08-01

    In children with dyslexia, deficits in working memory have not been well-specified. We assessed second-grade children with dyslexia, with and without concomitant specific language impairment, and children with typical development. Immediate serial recall of lists of phonological (non-word), lexical (digit), spatial (location) and visual (shape) items were included. For the latter three modalities, we used not only standard span but also running span tasks, in which the list length was unpredictable to limit mnemonic strategies. Non-word repetition tests indicated a phonological memory deficit in children with dyslexia alone compared with those with typical development, but this difference vanished when these groups were matched for non-verbal intelligence and language. Theoretically important deficits in serial order memory in dyslexic children, however, persisted relative to matched typically developing children. The deficits were in recall of (1) spoken digits in both standard and running span tasks and (2) spatial locations, in running span only. Children with dyslexia with versus without language impairment, when matched on non-verbal intelligence, had comparable serial order memory, but differed in phonology. Because serial orderings of verbal and spatial elements occur in reading, the careful examination of order memory may allow a deeper understanding of dyslexia and its relation to language impairment. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

  13. The effects of experimental pain and induced optimism on working memory task performance.

    PubMed

    Boselie, Jantine J L M; Vancleef, Linda M G; Peters, Madelon L

    2016-07-01

    Pain can interrupt and deteriorate executive task performance. We have previously shown that experimentally induced optimism can diminish the deteriorating effect of cold pressor pain on a subsequent working memory task (i.e., operation span task). In two successive experiments we sought further evidence for the protective role of optimism on pain-induced working memory impairments. We used another working memory task (i.e., 2-back task) that was performed either after or during pain induction. Study 1 employed a 2 (optimism vs. no-optimism)×2 (pain vs. no-pain)×2 (pre-score vs. post-score) mixed factorial design. In half of the participants optimism was induced by the Best Possible Self (BPS) manipulation, which required them to write and visualize about a life in the future where everything turned out for the best. In the control condition, participants wrote and visualized a typical day in their life (TD). Next, participants completed either the cold pressor task (CPT) or a warm water control task (WWCT). Before (baseline) and after the CPT or WWCT participants working memory performance was measured with the 2-back task. The 2-back task measures the ability to monitor and update working memory representation by asking participants to indicate whether the current stimulus corresponds to the stimulus that was presented 2 stimuli ago. Study 2 had a 2 (optimism vs. no-optimism)×2 (pain vs. no-pain) mixed factorial design. After receiving the BPS or control manipulation, participants completed the 2-back task twice: once with painful heat stimulation, and once without any stimulation (counter-balanced order). Continuous heat stimulation was used with temperatures oscillating around 1°C above and 1°C below the individual pain threshold. In study 1, the results did not show an effect of cold pressor pain on subsequent 2-back task performance. Results of study 2 indicated that heat pain impaired concurrent 2-back task performance. However, no evidence was found that optimism protected against this pain-induced performance deterioration. Experimentally induced pain impairs concurrent but not subsequent working memory task performance. Manipulated optimism did not counteract pain-induced deterioration of 2-back performance. It is important to explore factors that may diminish the negative impact of pain on the ability to function in daily life, as pain itself often cannot be remediated. We are planning to conduct future studies that should shed further light on the conditions, contexts and executive operations for which optimism can act as a protective factor. Copyright © 2016 Scandinavian Association for the Study of Pain. Published by Elsevier B.V. All rights reserved.

  14. An application of multiattribute decision analysis to the Space Station Freedom program. Case study: Automation and robotics technology evaluation

    NASA Technical Reports Server (NTRS)

    Smith, Jeffrey H.; Levin, Richard R.; Carpenter, Elisabeth J.

    1990-01-01

    The results are described of an application of multiattribute analysis to the evaluation of high leverage prototyping technologies in the automation and robotics (A and R) areas that might contribute to the Space Station (SS) Freedom baseline design. An implication is that high leverage prototyping is beneficial to the SS Freedom Program as a means for transferring technology from the advanced development program to the baseline program. The process also highlights the tradeoffs to be made between subsidizing high value, low risk technology development versus high value, high risk technology developments. Twenty one A and R Technology tasks spanning a diverse array of technical concepts were evaluated using multiattribute decision analysis. Because of large uncertainties associated with characterizing the technologies, the methodology was modified to incorporate uncertainty. Eight attributes affected the rankings: initial cost, operation cost, crew productivity, safety, resource requirements, growth potential, and spinoff potential. The four attributes of initial cost, operations cost, crew productivity, and safety affected the rankings the most.

  15. STAR Algorithm Integration Team - Facilitating operational algorithm development

    NASA Astrophysics Data System (ADS)

    Mikles, V. J.

    2015-12-01

    The NOAA/NESDIS Center for Satellite Research and Applications (STAR) provides technical support of the Joint Polar Satellite System (JPSS) algorithm development and integration tasks. Utilizing data from the S-NPP satellite, JPSS generates over thirty Environmental Data Records (EDRs) and Intermediate Products (IPs) spanning atmospheric, ocean, cryosphere, and land weather disciplines. The Algorithm Integration Team (AIT) brings technical expertise and support to product algorithms, specifically in testing and validating science algorithms in a pre-operational environment. The AIT verifies that new and updated algorithms function in the development environment, enforces established software development standards, and ensures that delivered packages are functional and complete. AIT facilitates the development of new JPSS-1 algorithms by implementing a review approach based on the Enterprise Product Lifecycle (EPL) process. Building on relationships established during the S-NPP algorithm development process and coordinating directly with science algorithm developers, the AIT has implemented structured reviews with self-contained document suites. The process has supported algorithm improvements for products such as ozone, active fire, vegetation index, and temperature and moisture profiles.

  16. Skilled deaf readers have an enhanced perceptual span in reading.

    PubMed

    Bélanger, Nathalie N; Slattery, Timothy J; Mayberry, Rachel I; Rayner, Keith

    2012-07-01

    Recent evidence suggests that, compared with hearing people, deaf people have enhanced visual attention to simple stimuli viewed in the parafovea and periphery. Although a large part of reading involves processing the fixated words in foveal vision, readers also utilize information in parafoveal vision to preprocess upcoming words and decide where to look next. In the study reported here, we investigated whether auditory deprivation affects low-level visual processing during reading by comparing the perceptual span of deaf signers who were skilled and less-skilled readers with the perceptual span of skilled hearing readers. Compared with hearing readers, the two groups of deaf readers had a larger perceptual span than would be expected given their reading ability. These results provide the first evidence that deaf readers' enhanced attentional allocation to the parafovea is used during complex cognitive tasks, such as reading.

  17. 77 FR 57024 - Drawbridge Operation Regulation; Tombigbee River, AL

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-09-17

    ... lift span bridge across the Tombigbee River at Naheola, Marengo and Choctaw Counties, Alabama. The... MNBR vertical lift span bridge crosses the Tombigbee River at mile 128.6 (Black Warrior Tombigbee... Meridian and Bigbee Railroad (MNBR) vertical lift span bridge across the Tombigbee River, mile 128.6 (Black...

  18. 77 FR 25655 - Drawbridge Operation Regulation; Tombigbee River, AL

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-05-01

    ... Meridian and Bigbee Railroad (MNBR) vertical lift span bridge across the Tombigbee River at Naheola... The MNBR vertical lift span bridge crosses the Tombigbee River at mile 128.6 (Black Warrior Tombigbee... Railroad (MNBR) vertical lift span bridge across the Tombigbee River, mile 128.6 (Black Warrior Tombigbee...

  19. Common constraints limit Korean and English character recognition in peripheral vision.

    PubMed

    He, Yingchen; Kwon, MiYoung; Legge, Gordon E

    2018-01-01

    The visual span refers to the number of adjacent characters that can be recognized in a single glance. It is viewed as a sensory bottleneck in reading for both normal and clinical populations. In peripheral vision, the visual span for English characters can be enlarged after training with a letter-recognition task. Here, we examined the transfer of training from Korean to English characters for a group of bilingual Korean native speakers. In the pre- and posttests, we measured visual spans for Korean characters and English letters. Training (1.5 hours × 4 days) consisted of repetitive visual-span measurements for Korean trigrams (strings of three characters). Our training enlarged the visual spans for Korean single characters and trigrams, and the benefit transferred to untrained English symbols. The improvement was largely due to a reduction of within-character and between-character crowding in Korean recognition, as well as between-letter crowding in English recognition. We also found a negative correlation between the size of the visual span and the average pattern complexity of the symbol set. Together, our results showed that the visual span is limited by common sensory (crowding) and physical (pattern complexity) factors regardless of the language script, providing evidence that the visual span reflects a universal bottleneck for text recognition.

  20. Common constraints limit Korean and English character recognition in peripheral vision

    PubMed Central

    He, Yingchen; Kwon, MiYoung; Legge, Gordon E.

    2018-01-01

    The visual span refers to the number of adjacent characters that can be recognized in a single glance. It is viewed as a sensory bottleneck in reading for both normal and clinical populations. In peripheral vision, the visual span for English characters can be enlarged after training with a letter-recognition task. Here, we examined the transfer of training from Korean to English characters for a group of bilingual Korean native speakers. In the pre- and posttests, we measured visual spans for Korean characters and English letters. Training (1.5 hours × 4 days) consisted of repetitive visual-span measurements for Korean trigrams (strings of three characters). Our training enlarged the visual spans for Korean single characters and trigrams, and the benefit transferred to untrained English symbols. The improvement was largely due to a reduction of within-character and between-character crowding in Korean recognition, as well as between-letter crowding in English recognition. We also found a negative correlation between the size of the visual span and the average pattern complexity of the symbol set. Together, our results showed that the visual span is limited by common sensory (crowding) and physical (pattern complexity) factors regardless of the language script, providing evidence that the visual span reflects a universal bottleneck for text recognition. PMID:29327041

  1. Narrative abilities, memory and attention in children with a specific language impairment.

    PubMed

    Duinmeijer, Iris; de Jong, Jan; Scheper, Annette

    2012-01-01

    While narrative tasks have proven to be valid measures for detecting language disorders, measuring communicative skills and predicting future academic performance, research into the comparability of different narrative tasks has shown that outcomes are dependent on the type of task used. Although many of the studies detecting task differences touch upon the fact that tasks place differential demands on cognitive abilities like auditory attention and memory, few studies have related specific narrative tasks to these cognitive abilities. Examining this relation is especially warranted for children with specific language impairment (SLI), who are characterized by language problems, but often have problems in other cognitive domains as well. In the current research, a comparison was made between a story retelling task (The Bus Story) and a story generation task (The Frog Story) in a group of children with SLI (n= 34) and a typically developing group (n= 38) from the same age range. In addition to the two narrative tasks, sustained auditory attention (TEA-Ch) and verbal working memory (WISC digit span and the Dutch version of the CVLT-C word list recall) were measured. Correlations were computed between the narrative, the memory and the attention scores. A group comparison showed that the children with SLI scored significantly worse than the typically developing children on several narrative measures as well as on sustained auditory attention and verbal working memory. A within-subjects comparison of the scores on the two narrative tasks showed a contrast between the tasks on several narrative measures. Furthermore, correlational analyses showed that, on the level of plot structure, the story generation task correlated with sustained auditory attention, while the story retelling task correlated with word list recall. Mean length of utterance (MLU) on the other hand correlated with digit span but not with sustained auditory attention. While children with SLI have problems with narratives in general, their performance is also dependent on the specific elicitation task used for research or diagnostics. Various narrative tasks generate different scores and are differentially correlated to cognitive skills like attention and memory, making the selection of a given task crucial in the clinical setting. © 2012 Royal College of Speech and Language Therapists.

  2. Intact short-term memory and impaired executive functions in obsessive compulsive disorder.

    PubMed

    Demeter, Gyula; Racsmány, Mihály; Csigó, Katalin; Harsányi, András; Németh, Attila; Döme, László

    2013-01-30

    Previous neuropsychological studies produced inconsistent results with tasks tapping short-term verbal and visual-spatial memory and executive functions in obsessive compulsive disorder (OCD). The aim of this study was to investigate the presence of deficits in these cognitive domains. A further goal was to describe the distribution of patients in different impairment ranges for all functions, and clarify the relationship between symptom severity and cognitive impairments. Thirty patients with OCD (DSM-IV) and 30 healthy volunteers were compared using well-known neuropsychological tasks. We assessed short-term verbal memory with the Digit Span Forward and Digit Span Backward Tasks, short-term visual-spatial memory with the Corsi Block Tapping Task, while we measured the level of executive functions with the StroopTask and the Wisconsin Card Sorting Test (WCST). Compared with a matched healthy control group, the performance of OCD patients was in the impaired range only in the two executive tasks. We find a significant positive correlations between the Y-BOCS (Yale-Brown Obsessive Compulsive Scale) total scores and the number of perseverative responses (r(28) = 0.409, p < 0.05) and perseverative errors (r(28) = 0.385, p < 0.05) in the WCST. Our results gave evidence that executive functions are impaired while short-term memory is intact in OCD. This is in line with neuropsychological model of OCD that the deficit of cognitive and behavioral inhibition are responsible for the main cognitive findings of this disorder, most prevalently the deficit in set shifting and prepotent response inhibition.

  3. A Virtual Object-Location Task for Children: Gender and Videogame Experience Influence Navigation; Age Impacts Memory and Completion Time

    PubMed Central

    Rodriguez-Andres, David; Mendez-Lopez, Magdalena; Juan, M.-Carmen; Perez-Hernandez, Elena

    2018-01-01

    The use of virtual reality-based tasks for studying memory has increased considerably. Most of the studies that have looked at child population factors that influence performance on such tasks have been focused on cognitive variables. However, little attention has been paid to the impact of non-cognitive skills. In the present paper, we tested 52 typically-developing children aged 5–12 years in a virtual object-location task. The task assessed their spatial short-term memory for the location of three objects in a virtual city. The virtual task environment was presented using a 3D application consisting of a 120″ stereoscopic screen and a gamepad interface. Measures of learning and displacement indicators in the virtual environment, 3D perception, satisfaction, and usability were obtained. We assessed the children’s videogame experience, their visuospatial span, their ability to build blocks, and emotional and behavioral outcomes. The results indicate that learning improved with age. Significant effects on the speed of navigation were found favoring boys and those more experienced with videogames. Visuospatial skills correlated mainly with ability to recall object positions, but the correlation was weak. Longer paths were related with higher scores of withdrawal behavior, attention problems, and a lower visuospatial span. Aggressiveness and experience with the device used for interaction were related with faster navigation. However, the correlations indicated only weak associations among these variables. PMID:29674988

  4. Cognitive and behavioural dispositions in offspring at high risk for alcoholism.

    PubMed

    Kumar, Rajesh; Kumar, Keshav Janakiprasad; Benegal, Vivek

    2018-06-01

    Offspring with family history of alcoholism are considered to be at high risk for alcoholism. The present study sought to expand our understanding of cognitive and behavioural dispositions associated with executive control and self-regulation in alcohol naïve offspring with and without family history of alcoholism. Sample comprised of alcohol naive offspring in two groups: (i) at high risk (n = 34) and (ii) at low risk for alcoholism (n = 34). Both groups were matched on age (+/-1 year), education (+/-1 year) and gender. Measures used were: Mini-International Neuropsychiatric Interview, Family Interview for Genetic Studies, Socio-demographic Data Sheet, Annett's Handedness Questionnaire, Barratt's Impulsiveness Scale-version 11, Digit Span Test, Spatial Span Test, Tower of London, Wisconsin Card Sorting Test, Iowa Gambling Task (IGT) and Game of Dice Task (GDT). Results showed that alcohol naive offspring at high risk for alcoholism reported significantly high impulsivity and demonstrated significant differences on executive functions and decision making tasks. Correlation analysis revealed that high impulsivity was significantly associated with poor performance on explicit decision making task (GDT) and executive function task (WCST). There was no significant correlation between two decision making tasks (IGT and GDT) in both groups and performance on IGT was not significantly associated with impulsivity and executive functions. The present study indicates cognitive and behavioural dispositions in alcohol naive offspring at high risk for alcoholism and support the sub-optimal balance between reflective and impulsive system responsible for addiction. Furthermore, present study supports separability between two different types of decision making tasks. Copyright © 2018 Elsevier B.V. All rights reserved.

  5. Pupillary Responses as a Biomarker of Diminished Effort Associated With Defeatist Attitudes and Negative Symptoms in Schizophrenia.

    PubMed

    Granholm, Eric; Ruiz, Ivan; Gallegos-Rodriguez, Yuliana; Holden, Jason; Link, Peter C

    2016-10-15

    The hypothesis that defeatist performance attitudes are associated with decreased goal-directed task effort and negative symptoms in consumers with schizophrenia was investigated by using pupillary responses as a biomarker of task effort. Pupillary dilation during cognitive tasks provides a biomarker of effort devoted to the task, with greater dilation indicating greater effort. Defeatist attitudes were assessed in 149 consumers with schizophrenia or schizoaffective disorder and 50 healthy control subjects, and consumers were divided into three groups (tertile split) with respect to severity of defeatist attitudes. Pupillary dilation responses were recorded during a digit-span task with three-, six-, and nine-digit spans. Effort allocation (pupillary responses) to the task increased as the processing load increased from low (three-digit) to moderate (six-digit) demands in healthy control subjects and consumers with schizophrenia with mild and moderate severity of defeatist attitudes. In contrast, consumers with severe defeatist attitudes did not increase their effort when processing demands increased from low to moderate loads. These consumers showed significantly less effort in the six-digit condition relative to consumers with mild defeatist attitudes. Moreover, consumers with severe defeatist attitudes showed significantly greater severity of negative symptoms relative to consumers with mild defeatist attitudes and negative symptoms were significantly correlated with defeatist attitudes. These results suggest a relationship between defeatist performance attitudes, goal-directed task effort indexed by pupillary responses, and negative symptoms in schizophrenia. The findings have implications for using cognitive therapy to reduce defeatist attitudes that may contribute to diminished effort and negative symptoms in schizophrenia. Published by Elsevier Inc.

  6. Older Women's Development: A Comparison of Women in Their 60s and 80s on a Measure of Erikson's Developmental Tasks.

    ERIC Educational Resources Information Center

    Norman, Suzanne M.; McCluskey-Fawcett, Kathleen; Ashcraft, Lisa

    2002-01-01

    Compares women from two ages groups in order to understand their development across the life span. Measures of Psychosocial Development, which assesses Erikson's developmental stages, were administered to 41 women in 2 cohorts (ages 60-70, ages 80-90). Age group differences in the resolution of Erikson's identity and trust developmental tasks were…

  7. 40 CFR 60.753 - Operational standards for collection and control systems.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Performance for Municipal Solid Waste Landfills § 60.753 Operational standards for collection and control... that gas is collected from each area, cell, or group of cells in the MSW landfill in which solid waste... two calibration gases are required, a zero and span, and ambient air may be used as the span; (iv) A...

  8. 40 CFR 60.753 - Operational standards for collection and control systems.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Performance for Municipal Solid Waste Landfills § 60.753 Operational standards for collection and control... that gas is collected from each area, cell, or group of cells in the MSW landfill in which solid waste... two calibration gases are required, a zero and span, and ambient air may be used as the span; (iv) A...

  9. The smartphone and the driver's cognitive workload: A comparison of Apple, Google, and Microsoft's intelligent personal assistants.

    PubMed

    Strayer, David L; Cooper, Joel M; Turrill, Jonna; Coleman, James R; Hopman, Rachel J

    2017-06-01

    The goal of this research was to examine the impact of voice-based interactions using 3 different intelligent personal assistants (Apple's Siri , Google's Google Now for Android phones, and Microsoft's Cortana ) on the cognitive workload of the driver. In 2 experiments using an instrumented vehicle on suburban roadways, we measured the cognitive workload of drivers when they used the voice-based features of each smartphone to place a call, select music, or send text messages. Cognitive workload was derived from primary task performance through video analysis, secondary-task performance using the Detection Response Task (DRT), and subjective mental workload. We found that workload was significantly higher than that measured in the single-task drive. There were also systematic differences between the smartphones: The Google system placed lower cognitive demands on the driver than the Apple and Microsoft systems, which did not differ. Video analysis revealed that the difference in mental workload between the smartphones was associated with the number of system errors, the time to complete an action, and the complexity and intuitiveness of the devices. Finally, surprisingly high levels of cognitive workload were observed when drivers were interacting with the devices: "on-task" workload measures did not systematically differ from that associated with a mentally demanding Operation Span (OSPAN) task. The analysis also found residual costs associated using each of the smartphones that took a significant time to dissipate. The data suggest that caution is warranted in the use of smartphone voice-based technology in the vehicle because of the high levels of cognitive workload associated with these interactions. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  10. Publishing data from electronic health records while preserving privacy: a survey of algorithms.

    PubMed

    Gkoulalas-Divanis, Aris; Loukides, Grigorios; Sun, Jimeng

    2014-08-01

    The dissemination of Electronic Health Records (EHRs) can be highly beneficial for a range of medical studies, spanning from clinical trials to epidemic control studies, but it must be performed in a way that preserves patients' privacy. This is not straightforward, because the disseminated data need to be protected against several privacy threats, while remaining useful for subsequent analysis tasks. In this work, we present a survey of algorithms that have been proposed for publishing structured patient data, in a privacy-preserving way. We review more than 45 algorithms, derive insights on their operation, and highlight their advantages and disadvantages. We also provide a discussion of some promising directions for future research in this area. Copyright © 2014 Elsevier Inc. All rights reserved.

  11. BigBOSS: The Ground-Based Stage IV BAO Experiment

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Schlegel, David; Bebek, Chris; Heetderks, Henry

    2009-04-01

    The BigBOSS experiment is a proposed DOE-NSF Stage IV ground-based dark energy experiment to study baryon acoustic oscillations (BAO) and the growth of structure with an all-sky galaxy redshift survey. The project is designed to unlock the mystery of dark energy using existing ground-based facilities operated by NOAO. A new 4000-fiber R=5000 spectrograph covering a 3-degree diameter field will measure BAO and redshift space distortions in the distribution of galaxies and hydrogen gas spanning redshifts from 0.2< z< 3.5. The Dark Energy Task Force figure of merit (DETF FoM) for this experiment is expected to be equal to that ofmore » a JDEM mission for BAO with the lower risk and cost typical of a ground-based experiment.« less

  12. Sex differences in spatial memory using serial and search tasks.

    PubMed

    Shah, Darshna S; Prados, Jose; Gamble, Jasmin; De Lillo, Carlo; Gibson, Claire L

    2013-11-15

    The present study assessed the spatial abilities of male and female human participants using different versions of the non-navigational Corsi block-tapping test (CBT) and a search task. Males performed significantly better than females on the standard manual version of the CBT; however, the standard CBT does not allow discrimination between spatial memory span and the role of spatial organisational factors (structure, path length and presence of crossings) in the sequences to recall. These organisational factors were assessed, therefore, in an experiment in which 7-block-sequences had to be recalled in a computerised version of the CBT. No sex differences in performance were observed on the computerised CBT, indicating that males do not make better use of spatial organisational principles. Accordingly, sex differences observed in the manual CBT are likely to rely upon differences in memory span between males and females. In the search task, participants could locate a goal by reference to a Euclidian space (the geometry of a virtual enclose) or to proximal non-geometric cues. Both male and female participants showed a preference for the non-geometric cues, which overshadowed learning about the geometric cues when the two sets were available simultaneously during the training stage. These results indicate that sex differences do exist in those tests which are dependent on memory span. Sex differences were absent, however, in spatial organisational skills or in the usage of Euclidian and egocentric strategies to solve problems relying on spatial ability. Copyright © 2013 Elsevier B.V. All rights reserved.

  13. Extending the Query Language of a Data Warehouse for Patient Recruitment.

    PubMed

    Dietrich, Georg; Ertl, Maximilian; Fette, Georg; Kaspar, Mathias; Krebs, Jonathan; Mackenrodt, Daniel; Störk, Stefan; Puppe, Frank

    2017-01-01

    Patient recruitment for clinical trials is a laborious task, as many texts have to be screened. Usually, this work is done manually and takes a lot of time. We have developed a system that automates the screening process. Besides standard keyword queries, the query language supports extraction of numbers, time-spans and negations. In a feasibility study for patient recruitment from a stroke unit with 40 patients, we achieved encouraging extraction rates above 95% for numbers and negations and ca. 86% for time spans.

  14. 77 FR 42432 - Drawbridge Operation Regulations; Niantic River, Niantic, CT

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-07-19

    ... work on machinery and the lift span. DATES: This deviation is effective from 9 p.m. on July 15, 2012... order to facilitate completion of machinery installation and lift span work at the new railroad bridge... and lift span work may continue. This scenario was presented to the Amtrak Annual Boaters Meeting on...

  15. Neuropsychological correlates of sustained attention in schizophrenia.

    PubMed

    Chen, E Y; Lam, L C; Chen, R Y; Nguyen, D G; Chan, C K; Wilkins, A J

    1997-04-11

    We employed a simple and relatively undemanding task of monotone counting for the assessment of sustained attention in schizophrenic patients. The monotone counting task has been validated neuropsychologically and is particularly sensitive to right prefrontal lesions. We compared the performance of schizophrenic patients with age- and education-matched controls. We then explored the extent to which a range of commonly employed neuropsychological tasks in schizophrenia research are related to attentional impairment as measured in this way. Monotone counting performance was found to be correlated with digit span (WAIS-R-HK), information (WAIS-R-HK), comprehension (WAIS-R-HK), logical memory (immediate recall) (Weschler Memory Scale, WMS), and visual reproduction (WMS). Multiple regression analysis also identified visual reproduction, digit span and comprehension as significant predictors of attention performance. In contrast, logical memory (delay recall) (WMS), similarity (WAIS-R-HK), semantic fluency, and Wisconsin Card Sorting Test (perseverative errors) were not correlated with attention. In addition, no significant correlation between sustained attention and symptoms was found. These findings are discussed in the context of a weakly modular cognitive system where attentional impairment may contribute selectively to a range of other cognitive deficits.

  16. Hippocampal Structure Predicts Statistical Learning and Associative Inference Abilities during Development.

    PubMed

    Schlichting, Margaret L; Guarino, Katharine F; Schapiro, Anna C; Turk-Browne, Nicholas B; Preston, Alison R

    2017-01-01

    Despite the importance of learning and remembering across the lifespan, little is known about how the episodic memory system develops to support the extraction of associative structure from the environment. Here, we relate individual differences in volumes along the hippocampal long axis to performance on statistical learning and associative inference tasks-both of which require encoding associations that span multiple episodes-in a developmental sample ranging from ages 6 to 30 years. Relating age to volume, we found dissociable patterns across the hippocampal long axis, with opposite nonlinear volume changes in the head and body. These structural differences were paralleled by performance gains across the age range on both tasks, suggesting improvements in the cross-episode binding ability from childhood to adulthood. Controlling for age, we also found that smaller hippocampal heads were associated with superior behavioral performance on both tasks, consistent with this region's hypothesized role in forming generalized codes spanning events. Collectively, these results highlight the importance of examining hippocampal development as a function of position along the hippocampal axis and suggest that the hippocampal head is particularly important in encoding associative structure across development.

  17. Executive function and attention span in euthymic patients with bipolar 1 disorder.

    PubMed

    Normala, I; Abdul, Hamid A R; Azlin, B; Nik Ruzyanei, N J; Hazli, Z; Shah, S A

    2010-09-01

    This is a cross sectional comparison study to assess executive function and attention span in euthymic patients with bipolar 1 disorder. It compares the performance of these two cognitive domains in 40 patients with bipolar 1 disorder to that of 40 healthy normal subjects using Trail Making (TMT), Digit Span (Forward and Backward) and Verbal Fluency (VF) tests. The association between demographic, clinical characteristics and performance in all tests were examined. Patients with bipolar illness showed significant impairment with moderate to large effect sizes (VF = 0.67, TMT A = 0.52, TMT B = 0.81, Digit Forward = 0.97, Digit backward = 1.10) in all tasks of executive and attention functioning. These impairments are observed in the absence of active mood symptoms while duration and severity of illness are not found to have an effect on both cognitive domains. Medications received by patients with bipolar disorder have significant association with performance on executive tasks. The results of this study add on to the existing global evidence of cognitive impairment in bipolar illness despite its cross cultural differences. Its presence in the absence of mania, depression or mixed episode indicates that cognitive impairment is stable even after symptoms recovery.

  18. 37. View of the control house on the north tower ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    37. View of the control house on the north tower from the north span facing north. Note mirror and video camera used by bridge operator to check for vessel traffic prior to operating the bridge, loudspeaker and sirens to warn pedestrians and boaters. - Henry Ford Bridge, Spanning Cerritos Channel, Los Angeles-Long Beach Harbor, Los Angeles, Los Angeles County, CA

  19. Detailed view of one (1) end of the swing span, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Detailed view of one (1) end of the swing span, supported on a rest pier, with the span in the closed position and in the train operational mode. Note the end truss bearing where a steel wedge is in the driven position to complete the end bearing arrangement. The wedges are power-driven through the machinery crank arms shown, thus forcing the ends of the swing span truss upward. Note: The top of the old stone pies has been encased with a concrete collar to hold stone masonry together and strengthen truss bearing points. - Bridgeport Swing Span Bridge, Spanning Tennessee River, Bridgeport, Jackson County, AL

  20. Collimator optimization in myocardial perfusion SPECT using the ideal observer and realistic background variability for lesion detection and joint detection and localization tasks

    NASA Astrophysics Data System (ADS)

    Ghaly, Michael; Du, Yong; Links, Jonathan M.; Frey, Eric C.

    2016-03-01

    In SPECT imaging, collimators are a major factor limiting image quality and largely determine the noise and resolution of SPECT images. In this paper, we seek the collimator with the optimal tradeoff between image noise and resolution with respect to performance on two tasks related to myocardial perfusion SPECT: perfusion defect detection and joint detection and localization. We used the Ideal Observer (IO) operating on realistic background-known-statistically (BKS) and signal-known-exactly (SKE) data. The areas under the receiver operating characteristic (ROC) and localization ROC (LROC) curves (AUCd, AUCd+l), respectively, were used as the figures of merit for both tasks. We used a previously developed population of 54 phantoms based on the eXtended Cardiac Torso Phantom (XCAT) that included variations in gender, body size, heart size and subcutaneous adipose tissue level. For each phantom, organ uptakes were varied randomly based on distributions observed in patient data. We simulated perfusion defects at six different locations with extents and severities of 10% and 25%, respectively, which represented challenging but clinically relevant defects. The extent and severity are, respectively, the perfusion defect’s fraction of the myocardial volume and reduction of uptake relative to the normal myocardium. Projection data were generated using an analytical projector that modeled attenuation, scatter, and collimator-detector response effects, a 9% energy resolution at 140 keV, and a 4 mm full-width at half maximum (FWHM) intrinsic spatial resolution. We investigated a family of eight parallel-hole collimators that spanned a large range of sensitivity-resolution tradeoffs. For each collimator and defect location, the IO test statistics were computed using a Markov Chain Monte Carlo (MCMC) method for an ensemble of 540 pairs of defect-present and -absent images that included the aforementioned anatomical and uptake variability. Sets of test statistics were computed for both tasks and analyzed using ROC and LROC analysis methodologies. The results of this study suggest that collimators with somewhat poorer resolution and higher sensitivity than those of a typical low-energy high-resolution (LEHR) collimator were optimal for both defect detection and joint detection and localization tasks in myocardial perfusion SPECT for the range of defect sizes investigated. This study also indicates that optimizing instrumentation for a detection task may provide near-optimal performance on the more challenging detection-localization task.

  1. Avoiding the Potential Pitfalls of Using Negative Priming Tasks in Developmental Studies: Assessing Inhibitory Control in Children, Adolescents, and Adults

    ERIC Educational Resources Information Center

    Pritchard, Verena E.; Neumann, Ewald

    2009-01-01

    Despite being ignored, visual distractors often produce traceable negative priming (NP) effects that can be used to investigate inhibitory processes. Robust NP effects are typically found with young adults, but not with children. Using 2 different NP tasks, the authors compared NP in 5 different age groups spanning 5 to 25 years of age. The 1st…

  2. Differences in Attainment and Performance in a Foreign Language: The Role of Working Memory Capacity

    ERIC Educational Resources Information Center

    Gilabert, Roger; Munoz, Carmen

    2010-01-01

    The goal of this study is to investigate the role of working memory capacity in L2 attainment and performance. The study uses an L1 reading span task to measure working memory of a group of 59 high-intermediate/advanced learners of English, and a film retelling task to measure their oral production. The analysis first showed a moderate to high…

  3. Beyond Capacity Limitations II: Effects of Lexical Processes on Word Recall in Verbal Working Memory Tasks in Children with and without Specific Language Impairment

    ERIC Educational Resources Information Center

    Mainela-Arnold, Elina; Evans, Julia L.; Coady, Jeffry

    2010-01-01

    Purpose: This study investigated the impact of lexical processes on target word recall in sentence span tasks in children with and without specific language impairment (SLI). Method: Participants were 42 children (ages 8;2-12;3 [years;months]): 21 with SLI and 21 typically developing peers matched on age and nonverbal IQ. Children completed a…

  4. Effects of electromagnetic fields emitted by GSM phones on working memory: a meta-analysis.

    PubMed

    Zubko, O; Gould, R L; Gay, H C; Cox, H J; Coulson, M C; Howard, R J

    2017-02-01

    Current treatments for Alzheimer's Disease (AD) do not affect the course of the illness and brain stimulation techniques are increasingly promoted as potential therapeutic interventions for AD. This study reviews the effects of electromagnetic field (EMF) exposure versus sham exposure on working memory (WM) performance of healthy human participants. Online literature databases and previous systematic reviews were searched for studies of EMF and WM in participants without reported memory problems. Two thousand eight hundred and fifty seven studies were identified, and 10 studies met the inclusion criteria. An assessment of study quality was completed, and separate, random effects meta-analyses were conducted for each of the three WM tasks included: n-back, substitution and digit span forward. No differences were found between participants exposed to active EMF versus sham conditions in any of the three working memory tasks examined. Results indicate that EMF does not affect WM during the n-back, substitution and digit-span tasks. Future studies should focus on the possible effects of chronic exposure to EMF in older adults with AD using a battery of comparable WM and attention tasks, before EMF can be seriously considered as a potential modulator of WM in AD. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

  5. Good distractions: Testing the effects of listening to an audiobook on driving performance in simple and complex road environments.

    PubMed

    Nowosielski, Robert J; Trick, Lana M; Toxopeus, Ryan

    2018-02-01

    Distracted driving (driving while performing a secondary task) causes many collisions. Most research on distracted driving has focused on operating a cell-phone, but distracted driving can include eating while driving, conversing with passengers or listening to music or audiobooks. Although the research has focused on the deleterious effects of distraction, there may be situations where distraction improves driving performance. Fatigue and boredom are also associated with collision risk and it is possible that secondary tasks can help alleviate the effects of fatigue and boredom. Furthermore, it has been found that individuals with high levels of executive functioning as measured by the OSPAN (Operation Span) task show better driving while multitasking. In this study, licensed drivers were tested in a driving simulator (a car body surrounded by screens) that simulated simple or complex roads. Road complexity was manipulated by increasing traffic, scenery, and the number of curves in the drive. Participants either drove, or drove while listening to an audiobook. Driving performance was measured in terms of braking response time to hazards (HRT): the time required to brake in response to pedestrians or vehicles that suddenly emerged from the periphery into the path of the vehicle, speed, standard deviation of speed, standard deviation of lateral position (SDLP). Overall, braking times to hazards were higher on the complex drive than the simple one, though the effects of secondary tasks such as audiobooks were especially deleterious on the complex drive. In contrast, on the simple drive, driving while listening to an audiobook lead to faster HRT. We found evidence that individuals with high OSPAN scores had faster HRTs when listening to an audiobook. These results suggest that there are environmental and individual factors behind difference in the allocation of attention while listening to audiobooks while driving. Copyright © 2017 Elsevier Ltd. All rights reserved.

  6. On the design of fault-tolerant robotic manipulator systems

    NASA Technical Reports Server (NTRS)

    Tesar, Delbert

    1993-01-01

    Robotic systems are finding increasing use in space applications. Many of these devices are going to be operational on board the Space Station Freedom. Fault tolerance has been deemed necessary because of the criticality of the tasks and the inaccessibility of the systems to maintenance and repair. Design for fault tolerance in manipulator systems is an area within robotics that is without precedence in the literature. In this paper, we will attempt to lay down the foundations for such a technology. Design for fault tolerance demands new and special approaches to design, often at considerable variance from established design practices. These design aspects, together with reliability evaluation and modeling tools, are presented. Mechanical architectures that employ protective redundancies at many levels and have a modular architecture are then studied in detail. Once a mechanical architecture for fault tolerance has been derived, the chronological stages of operational fault tolerance are investigated. Failure detection, isolation, and estimation methods are surveyed, and such methods for robot sensors and actuators are derived. Failure recovery methods are also presented for each of the protective layers of redundancy. Failure recovery tactics often span all of the layers of a control hierarchy. Thus, a unified framework for decision-making and control, which orchestrates both the nominal redundancy management tasks and the failure management tasks, has been derived. The well-developed field of fault-tolerant computers is studied next, and some design principles relevant to the design of fault-tolerant robot controllers are abstracted. Conclusions are drawn, and a road map for the design of fault-tolerant manipulator systems is laid out with recommendations for a 10 DOF arm with dual actuators at each joint.

  7. 77 FR 14689 - Drawbridge Operation Regulation; Berwick Bay (Atchafalaya River), Morgan City, LA

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-13

    ... Fe (BNSF) Railway Company vertical lift span bridge across Berwick Bay, mile 0.4, (Atchafalaya River... vertical lift span railroad bridge across Berwick Bay, mile 0.4 (Atchafalaya River, mile 17.5), at Morgan City, St. Mary Parish, Louisiana. The vertical lift span bridge has a vertical clearance of 6.4 feet...

  8. Long-term semantic representations moderate the effect of attentional refreshing on episodic memory.

    PubMed

    Loaiza, Vanessa M; Duperreault, Kayla A; Rhodes, Matthew G; McCabe, David P

    2015-02-01

    The McCabe effect (McCabe, Journal of Memory and Language 58:480-494, 2008) refers to an advantage in episodic memory (EM) retrieval for memoranda studied in complex span versus simple span tasks, particularly for memoranda presented in earlier serial positions. This finding has been attributed to the necessity to refresh memoranda during complex span tasks that, in turn, promotes content-context binding in working memory (WM). Several frameworks have conceptualized WM as being embedded in long-term memory. Thus, refreshing may be less efficient when memoranda are not well-established in long-term semantic memory (SM). To investigate this, we presented words and nonwords in simple and complex span trials in order to manipulate the long-term semantic representations of the memoranda with the requirement to refresh the memoranda during WM. A recognition test was administered that required participants to make a remember-know decision for each memorandum recognized as old. The results replicated the McCabe effect, but only for words, and the beneficial effect of refreshing opportunities was exclusive to recollection. These results extend previous research by indicating that the predictive relationship between WM refreshing and long-term EM is specific to recollection and, furthermore, moderated by representations in long-term SM. This supports the predictions of WM frameworks that espouse the importance of refreshing in content-context binding, but also those that view WM as being an activated subset of and, therefore, constrained by the contents of long-term memory.

  9. Generalizing the dynamic field theory of spatial cognition across real and developmental time scales

    PubMed Central

    Simmering, Vanessa R.; Spencer, John P.; Schutte, Anne R.

    2008-01-01

    Within cognitive neuroscience, computational models are designed to provide insights into the organization of behavior while adhering to neural principles. These models should provide sufficient specificity to generate novel predictions while maintaining the generality needed to capture behavior across tasks and/or time scales. This paper presents one such model, the Dynamic Field Theory (DFT) of spatial cognition, showing new simulations that provide a demonstration proof that the theory generalizes across developmental changes in performance in four tasks—the Piagetian A-not-B task, a sandbox version of the A-not-B task, a canonical spatial recall task, and a position discrimination task. Model simulations demonstrate that the DFT can accomplish both specificity—generating novel, testable predictions—and generality—spanning multiple tasks across development with a relatively simple developmental hypothesis. Critically, the DFT achieves generality across tasks and time scales with no modification to its basic structure and with a strong commitment to neural principles. The only change necessary to capture development in the model was an increase in the precision of the tuning of receptive fields as well as an increase in the precision of local excitatory interactions among neurons in the model. These small quantitative changes were sufficient to move the model through a set of quantitative and qualitative behavioral changes that span the age range from 8 months to 6 years and into adulthood. We conclude by considering how the DFT is positioned in the literature, the challenges on the horizon for our framework, and how a dynamic field approach can yield new insights into development from a computational cognitive neuroscience perspective. PMID:17716632

  10. Enhancing cognition with video games: a multiple game training study.

    PubMed

    Oei, Adam C; Patterson, Michael D

    2013-01-01

    Previous evidence points to a causal link between playing action video games and enhanced cognition and perception. However, benefits of playing other video games are under-investigated. We examined whether playing non-action games also improves cognition. Hence, we compared transfer effects of an action and other non-action types that required different cognitive demands. We instructed 5 groups of non-gamer participants to play one game each on a mobile device (iPhone/iPod Touch) for one hour a day/five days a week over four weeks (20 hours). Games included action, spatial memory, match-3, hidden- object, and an agent-based life simulation. Participants performed four behavioral tasks before and after video game training to assess for transfer effects. Tasks included an attentional blink task, a spatial memory and visual search dual task, a visual filter memory task to assess for multiple object tracking and cognitive control, as well as a complex verbal span task. Action game playing eliminated attentional blink and improved cognitive control and multiple-object tracking. Match-3, spatial memory and hidden object games improved visual search performance while the latter two also improved spatial working memory. Complex verbal span improved after match-3 and action game training. Cognitive improvements were not limited to action game training alone and different games enhanced different aspects of cognition. We conclude that training specific cognitive abilities frequently in a video game improves performance in tasks that share common underlying demands. Overall, these results suggest that many video game-related cognitive improvements may not be due to training of general broad cognitive systems such as executive attentional control, but instead due to frequent utilization of specific cognitive processes during game play. Thus, many video game training related improvements to cognition may be attributed to near-transfer effects.

  11. Computerized spatial delayed recognition span task: a specific tool to assess visuospatial working memory

    PubMed Central

    Satler, Corina; Belham, Flávia Schechtman; Garcia, Ana; Tomaz, Carlos; Tavares, Maria Clotilde H.

    2015-01-01

    A new tablet device version (IOS platform) of the Spatial Delayed Recognition Span Task (SDRST) was developed with the aim of investigating visuospatial Working Memory (WM) abilities based on touchscreen technology. This new WM testing application will be available to download for free in Apple Store app (“SDRST app”). In order to verify the feasibility of this computer-based task, we conducted three experiments with different manipulations and groups of participants. We were interested in investigating if (1) the SDRST is sensitive enough to tap into cognitive differences brought by aging and dementia; (2) different experimental manipulations work successfully; (3) cortical brain activations seen in other WM tasks are also demonstrated here; and (4) non-human primates are able to answer the task. Performance (scores and response time) was better for young than older adults and higher for the latter when compared to Alzheimer’s disease (AD) patients. All groups performed better with facial stimuli than with images of scenes and with emotional than with neutral stimuli. Electrophysiology data showed activation on prefrontal and frontal areas of scalp, theta band activity on the midline area, and gamma activity in left temporal area. There are all scalp regions known to be related to attention and WM. Besides those data, our sample of adult captive capuchin monkeys (Sapajus libidinosus) answered the task above chance level. Taken together, these results corroborate the reliability of this new computer-based SDRST as a measure of visuospatial WM in clinical and non-clinical populations as well as in non-human primates. Its tablet app allows the task to be administered in a wide range of settings, including hospitals, homes, schools, laboratories, universities, and research institutions. PMID:25964758

  12. Computerized spatial delayed recognition span task: a specific tool to assess visuospatial working memory.

    PubMed

    Satler, Corina; Belham, Flávia Schechtman; Garcia, Ana; Tomaz, Carlos; Tavares, Maria Clotilde H

    2015-01-01

    A new tablet device version (IOS platform) of the Spatial Delayed Recognition Span Task (SDRST) was developed with the aim of investigating visuospatial Working Memory (WM) abilities based on touchscreen technology. This new WM testing application will be available to download for free in Apple Store app ("SDRST app"). In order to verify the feasibility of this computer-based task, we conducted three experiments with different manipulations and groups of participants. We were interested in investigating if (1) the SDRST is sensitive enough to tap into cognitive differences brought by aging and dementia; (2) different experimental manipulations work successfully; (3) cortical brain activations seen in other WM tasks are also demonstrated here; and (4) non-human primates are able to answer the task. Performance (scores and response time) was better for young than older adults and higher for the latter when compared to Alzheimer's disease (AD) patients. All groups performed better with facial stimuli than with images of scenes and with emotional than with neutral stimuli. Electrophysiology data showed activation on prefrontal and frontal areas of scalp, theta band activity on the midline area, and gamma activity in left temporal area. There are all scalp regions known to be related to attention and WM. Besides those data, our sample of adult captive capuchin monkeys (Sapajus libidinosus) answered the task above chance level. Taken together, these results corroborate the reliability of this new computer-based SDRST as a measure of visuospatial WM in clinical and non-clinical populations as well as in non-human primates. Its tablet app allows the task to be administered in a wide range of settings, including hospitals, homes, schools, laboratories, universities, and research institutions.

  13. Outsourcing cognitive control to the environment: adult age differences in the use of task cues.

    PubMed

    Spieler, Daniel H; Mayr, Ulrich; LaGrone, Susan

    2006-10-01

    When an initial phase of cued task switching is followed by a phase of single-task trials, older adults show difficulties changing to the more efficient single-task mode of processing (Mayr & Liebscher, 2001). In Experiment 1, we show that these costs follow older adults' continued tendency to inspect task cues even though these provide no new information. In Experiment 2, we included a condition in which task cues were eliminated from the display after the task-switching phase. In this condition, older adults behaved the same as younger adults, suggesting that the presence of the task cue is critical for observing age differences while switching from a "high-control" to a "low-control" mode of processing. We discuss our results in terms of a life-span shift with regard to the reliance on internal versus external sources of information under conditions of high-control demands.

  14. Theorizing and researching levels of processing in self-regulated learning.

    PubMed

    Winne, Philip H

    2018-03-01

    Deep versus surface knowledge is widely discussed by educational practitioners. A corresponding construct, levels of processing, has received extensive theoretical and empirical attention in learning science and psychology. In both arenas, lower levels of information and shallower levels of processing are predicted and generally empirically demonstrated to limit knowledge learners gain, curtail what they can do with newly acquired knowledge, and shorten the life span of recently acquired knowledge. I recapitulate major accounts of levels or depth of information and information processing to set a stage for conceptualizing, first, self-regulated learning (SRL) from this perspective and, second, how a "levels-sensitive" approach might be implemented in research about SRL. I merge the levels construct into a model of SRL (Winne, 2011, Handbook of self-regulation of learning and performance (pp. 15-32), New York: Routledge; Winne, 2017b, Handbook of self-regulation of learning and performance (2 nd ed.), New York: Routledge; Winne & Hadwin, 1998, Metacognition in educational theory and practice (pp. 277-304). Mahwah, NJ: Lawrence Erlbaum) conceptually and with respect to operationally defining the levels construct in the context of SRL in relation to each of the model's four phases - surveying task conditions, setting goals and planning, engaging the task, and composing major adaptations for future tasks. Select illustrations are provided for each phase of SRL. Regarding phase 3, a software system called nStudy is introduced as state-of-the-art instrumentation for gathering fine-grained, time-stamped trace data about information learners select for processing and operations they use to process that information. Self-regulated learning can be viewed through a lens of the levels construct, and operational definitions can be designed to research SRL with respect to levels. While information can be organized arbitrarily deeply, the levels construct may not be particularly useful for distinguishing among processes except in a sense that, because processes in SRL operate on information with depth, they epiphenomenally acquire characteristics of levels. Thus, SRL per se is not a deeper kind of processing. Instead, it is processing more complex - deeper - information about a different topic, namely processes for learning. © 2017 The British Psychological Society.

  15. 75 FR 18055 - Drawbridge Operation Regulation; Mermentau River, Grand Chenier, LA

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-04-09

    ... electrical and mechanical repairs pertaining to the bridge's main span drive assembly and system components... in order to perform electrical and mechanical repairs pertaining to the bridge's main span drive...

  16. 33 CFR 117.929 - Durham Creek.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... OPERATION REGULATIONS Specific Requirements South Carolina § 117.929 Durham Creek. The removable span of the... Charleston of an emergency in the Bushy Park Reservoir, the span shall be removed as soon as possible to...

  17. 33 CFR 117.929 - Durham Creek.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... OPERATION REGULATIONS Specific Requirements South Carolina § 117.929 Durham Creek. The removable span of the... Charleston of an emergency in the Bushy Park Reservoir, the span shall be removed as soon as possible to...

  18. Detail of middle panel at pivot pier and above the ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Detail of middle panel at pivot pier and above the two (2) center supports. The middle panel chords (not shown) were made strong enough to provide for the full bending moment with the span open and arms swinging. The middle posts support the operator's house. When closed, the bridge acts as two (2) separate simple spans, except a small amount of negative bending is accommodated due to a continuous condition. - Bridgeport Swing Span Bridge, Spanning Tennessee River, Bridgeport, Jackson County, AL

  19. The influence of linguistic and cognitive factors on the time course of verb-based implicit causality.

    PubMed

    Koornneef, Arnout; Dotlačil, Jakub; van den Broek, Paul; Sanders, Ted

    2016-01-01

    In three eye-tracking experiments the influence of the Dutch causal connective "want" (because) and the working memory capacity of readers on the usage of verb-based implicit causality was examined. Experiments 1 and 2 showed that although a causal connective is not required to activate implicit causality information during reading, effects of implicit causality surfaced more rapidly and were more pronounced when a connective was present in the discourse than when it was absent. In addition, Experiment 3 revealed that-in contrast to previous claims-the activation of implicit causality is not a resource-consuming mental operation. Moreover, readers with higher and lower working memory capacities behaved differently in a dual-task situation. Higher span readers were more likely to use implicit causality when they had all their working memory resources at their disposal. Lower span readers showed the opposite pattern as they were more likely to use the implicit causality cue in the case of an additional working memory load. The results emphasize that both linguistic and cognitive factors mediate the impact of implicit causality on text comprehension. The implications of these results are discussed in terms of the ongoing controversies in the literature-that is, the focusing-integration debate and the debates on the source of implicit causality.

  20. Beyond Capacity Limitations: Determinants of Word Recall Performance on Verbal Working Memory Span Tasks in Children With SLI

    PubMed Central

    Mainela-Arnold, Elina; Evans, Julia L.

    2016-01-01

    Reduced verbal working memory capacity has been proposed as a possible account of language impairments in specific language impairment (SLI). Studies have shown, however, that differences in strength of linguistic representations in the form of word frequency affect list recall and performance on verbal working memory tasks. This suggests that verbal memory capacity and long-term linguistic knowledge may not be distinct constructs. It has been suggested that linguistic representations in SLI are weak in ways that result in a breakdown in language processing on tasks that require manipulation of unfamiliar material. In this study, the effects of word frequency, long-term linguistic knowledge, and serial order position on recall performance in the competing language processing task (CLPT) were investigated in 10 children with SLI and 10 age-matched peers (age 8 years 6 months to 12 years 4 months). The children with SLI recalled significantly fewer target words on the CLPT as compared with their age-matched controls. The SLI group did not differ, however, in their ability to recall target words having high word frequency but were significantly poorer in their ability to recall words on the CLPT having low word frequency. Differences in receptive and expressive language abilities also appeared closely related to performance on the CLPT, suggesting that working memory capacity is not distinct from language knowledge and that degraded linguistic representations may have an effect on performance on verbal working memory span tasks in children with SLI. PMID:16378481

  1. Cognition and speech-in-noise recognition: the role of proactive interference.

    PubMed

    Ellis, Rachel J; Rönnberg, Jerker

    2014-01-01

    Complex working memory (WM) span tasks have been shown to predict speech-in-noise (SIN) recognition. Studies of complex WM span tasks suggest that, rather than indexing a single cognitive process, performance on such tasks may be governed by separate cognitive subprocesses embedded within WM. Previous research has suggested that one such subprocess indexed by WM tasks is proactive interference (PI), which refers to difficulties memorizing current information because of interference from previously stored long-term memory representations for similar information. The aim of the present study was to investigate phonological PI and to examine the relationship between PI (semantic and phonological) and SIN perception. A within-subjects experimental design was used. An opportunity sample of 24 young listeners with normal hearing was recruited. Measures of resistance to, and release from, semantic and phonological PI were calculated alongside the signal-to-noise ratio required to identify 50% of keywords correctly in a SIN recognition task. The data were analyzed using t-tests and correlations. Evidence of release from and resistance to semantic interference was observed. These measures correlated significantly with SIN recognition. Limited evidence of phonological PI was observed. The results show that capacity to resist semantic PI can be used to predict SIN recognition scores in young listeners with normal hearing. On the basis of these findings, future research will focus on investigating whether tests of PI can be used in the treatment and/or rehabilitation of hearing loss. American Academy of Audiology.

  2. LG based decision aid for naval tactical action officer's (TAO) workstation

    NASA Astrophysics Data System (ADS)

    Stilman, Boris; Yakhnis, Vladimir; Umanskiy, Oleg; Boyd, Ron

    2005-05-01

    In the increasingly NetCentric battlespace of the 21st century, Stilman Advanced Strategies Linguistic Geometry software has the potential to revolutionize the way that the Navy fights in two key areas: as a Tactical Decision Aid and for creating a relevant Common Operating Picture. Incorporating STILMAN's software into a prototype Tactical Action Officers (TAO) workstation as a Tactical Decision Aid (TDA) will allow warfighters to manage their assets more intelligently and effectively. This prototype workstation will be developed using human-centered design principles and will be an open, component-based architecture for combat control systems for future small surface combatants. It will integrate both uninhabited vehicles and onboard sensors and weapon systems across a squadron of small surface combatants. In addition, the hypergame representation of complex operations provides a paradigm for the presentation of a common operating picture to operators and personnel throughout the command hierarchy. In the hypergame technology there are game levels that span the range from the tactical to the global strategy level, with each level informing the others. This same principle will be applied to presenting the relevant common operating picture to operators. Each operator will receive a common operating picture that is appropriate for their level in the command hierarchy. The area covered by this operating picture and the level of detail contained within it will be dependent upon the specific tasks the operator is performing (supervisory vice tactical control) and the level of the operator (or command personnel) within the command hierarchy. Each level will inform the others to keep the picture concurrent and up-to-date.

  3. How a Multidimensional View of Perceived Organizational Support Impacts Self-Efficacy and Task Understanding during Training for Boundary Spanning Tasks

    DTIC Science & Technology

    2008-03-01

    Literature Review Chapter Overview This chapter provides an overview of recent studies and research on theory and application of self-efficacy...from the literature and how it has been used in predicting success in varying measures of performance. Self-efficacy Many psychological theories ...shown to positively affect training outcomes (Bandura, 1977, Salas & Cannon-Bowers, 2001). Theories of expectancy and self-efficacy suggest 10

  4. 77 FR 72737 - Drawbridge Operation Regulation; Mile 359.4, Missouri River, Kansas City, MO

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-12-06

    ... counterweight cables that facilitate movement of the lift span. This deviation allows the bridge to remain in... movement of the lift span are replaced. The closure period will start at 7 a.m. on February 11, 2013, and continue through 11 p.m. on March 2, 2013. Once the counterweight cables are removed, the lift span will...

  5. 76 FR 76298 - Drawbridge Operation Regulation; Old Brazos River, Freeport, Brazoria County, TX

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-12-07

    ... deviation allows the bridge to remain closed to navigation for four days to replace lift cables. DATES: This... deviation will allow the lift span of the bridge to remain in the closed-to-navigation position in order for.... The project involves the replacement of the old swing span with the current vertical lift span. Vessel...

  6. The Role of Visual Processing Speed in Reading Speed Development

    PubMed Central

    Lobier, Muriel; Dubois, Matthieu; Valdois, Sylviane

    2013-01-01

    A steady increase in reading speed is the hallmark of normal reading acquisition. However, little is known of the influence of visual attention capacity on children's reading speed. The number of distinct visual elements that can be simultaneously processed at a glance (dubbed the visual attention span), predicts single-word reading speed in both normal reading and dyslexic children. However, the exact processes that account for the relationship between the visual attention span and reading speed remain to be specified. We used the Theory of Visual Attention to estimate visual processing speed and visual short-term memory capacity from a multiple letter report task in eight and nine year old children. The visual attention span and text reading speed were also assessed. Results showed that visual processing speed and visual short term memory capacity predicted the visual attention span. Furthermore, visual processing speed predicted reading speed, but visual short term memory capacity did not. Finally, the visual attention span mediated the effect of visual processing speed on reading speed. These results suggest that visual attention capacity could constrain reading speed in elementary school children. PMID:23593117

  7. Young Skilled Deaf Readers Have an Enhanced Perceptual Span in Reading.

    PubMed

    Bélanger, Nathalie N; Lee, Michelle; Schotter, Elizabeth R

    2017-04-27

    Recently, Bélanger, Slattery, Mayberry and Rayner (2012) showed, using the moving window paradigm, that profoundly deaf adults have a wider perceptual span during reading relative to hearing adults matched on reading level. This difference might be related to the fact that deaf adults allocate more visual attention to simple stimuli in the parafovea (Bavelier, Dye & Hauser, 2006). Importantly, this reorganization of visual attention in deaf individuals is already manifesting in deaf children (Dye, Hauser & Bavelier, 2009). This leads to questions about the time course of the emergence of an enhanced perceptual span (which is under attentional control; Rayner, 2014; Miellet, O'Donnell, & Sereno, 2009) in young deaf readers. The present research addressed this question by comparing the perceptual spans of young deaf readers (age 7-15) and young hearing children (age 7-15). Young deaf readers, like deaf adults, were found to have a wider perceptual span relative to their hearing peers matched on reading level, suggesting that strong and early reorganization of visual attention in deaf individuals goes beyond the processing of simple visual stimuli and emerges into more cognitively complex tasks, such as reading.

  8. Comparing the visual spans for faces and letters

    PubMed Central

    He, Yingchen; Scholz, Jennifer M.; Gage, Rachel; Kallie, Christopher S.; Liu, Tingting; Legge, Gordon E.

    2015-01-01

    The visual span—the number of adjacent text letters that can be reliably recognized on one fixation—has been proposed as a sensory bottleneck that limits reading speed (Legge, Mansfield, & Chung, 2001). Like reading, searching for a face is an important daily task that involves pattern recognition. Is there a similar limitation on the number of faces that can be recognized in a single fixation? Here we report on a study in which we measured and compared the visual-span profiles for letter and face recognition. A serial two-stage model for pattern recognition was developed to interpret the data. The first stage is characterized by factors limiting recognition of isolated letters or faces, and the second stage represents the interfering effect of nearby stimuli on recognition. Our findings show that the visual span for faces is smaller than that for letters. Surprisingly, however, when differences in first-stage processing for letters and faces are accounted for, the two visual spans become nearly identical. These results suggest that the concept of visual span may describe a common sensory bottleneck that underlies different types of pattern recognition. PMID:26129858

  9. The role of visual processing speed in reading speed development.

    PubMed

    Lobier, Muriel; Dubois, Matthieu; Valdois, Sylviane

    2013-01-01

    A steady increase in reading speed is the hallmark of normal reading acquisition. However, little is known of the influence of visual attention capacity on children's reading speed. The number of distinct visual elements that can be simultaneously processed at a glance (dubbed the visual attention span), predicts single-word reading speed in both normal reading and dyslexic children. However, the exact processes that account for the relationship between the visual attention span and reading speed remain to be specified. We used the Theory of Visual Attention to estimate visual processing speed and visual short-term memory capacity from a multiple letter report task in eight and nine year old children. The visual attention span and text reading speed were also assessed. Results showed that visual processing speed and visual short term memory capacity predicted the visual attention span. Furthermore, visual processing speed predicted reading speed, but visual short term memory capacity did not. Finally, the visual attention span mediated the effect of visual processing speed on reading speed. These results suggest that visual attention capacity could constrain reading speed in elementary school children.

  10. Good Holders, Bad Shufflers: An Examination of Working Memory Processes and Modalities in Children with and without Attention-Deficit/Hyperactivity Disorder.

    PubMed

    Simone, Ashley N; Bédard, Anne-Claude V; Marks, David J; Halperin, Jeffrey M

    2016-01-01

    The aim of this study was to examine working memory (WM) modalities (visual-spatial and auditory-verbal) and processes (maintenance and manipulation) in children with and without attention-deficit/hyperactivity disorder (ADHD). The sample consisted of 63 8-year-old children with ADHD and an age- and sex-matched non-ADHD comparison group (N=51). Auditory-verbal and visual-spatial WM were assessed using the Digit Span and Spatial Span subtests from the Wechsler Intelligence Scale for Children Integrated - Fourth Edition. WM maintenance and manipulation were assessed via forward and backward span indices, respectively. Data were analyzed using a 3-way Group (ADHD vs. non-ADHD)×Modality (Auditory-Verbal vs. Visual-Spatial)×Condition (Forward vs. Backward) Analysis of Variance (ANOVA). Secondary analyses examined differences between Combined and Predominantly Inattentive ADHD presentations. Significant Group×Condition (p=.02) and Group×Modality (p=.03) interactions indicated differentially poorer performance by those with ADHD on backward relative to forward and visual-spatial relative to auditory-verbal tasks, respectively. The 3-way interaction was not significant. Analyses targeting ADHD presentations yielded a significant Group×Condition interaction (p=.009) such that children with ADHD-Predominantly Inattentive Presentation performed differentially poorer on backward relative to forward tasks compared to the children with ADHD-Combined Presentation. Findings indicate a specific pattern of WM weaknesses (i.e., WM manipulation and visual-spatial tasks) for children with ADHD. Furthermore, differential patterns of WM performance were found for children with ADHD-Predominantly Inattentive versus Combined Presentations. (JINS, 2016, 22, 1-11).

  11. Do dyslexic individuals present a reduced visual attention span? Evidence from visual recognition tasks of non-verbal multi-character arrays.

    PubMed

    Yeari, Menahem; Isser, Michal; Schiff, Rachel

    2017-07-01

    A controversy has recently developed regarding the hypothesis that developmental dyslexia may be caused, in some cases, by a reduced visual attention span (VAS). To examine this hypothesis, independent of phonological abilities, researchers tested the ability of dyslexic participants to recognize arrays of unfamiliar visual characters. Employing this test, findings were rather equivocal: dyslexic participants exhibited poor performance in some studies but normal performance in others. The present study explored four methodological differences revealed between the two sets of studies that might underlie their conflicting results. Specifically, in two experiments we examined whether a VAS deficit is (a) specific to recognition of multi-character arrays as wholes rather than of individual characters within arrays, (b) specific to characters' position within arrays rather than to characters' identity, or revealed only under a higher attention load due to (c) low-discriminable characters, and/or (d) characters' short exposure. Furthermore, in this study we examined whether pure dyslexic participants who do not have attention disorder exhibit a reduced VAS. Although comorbidity of dyslexia and attention disorder is common and the ability to sustain attention for a long time plays a major rule in the visual recognition task, the presence of attention disorder was neither evaluated nor ruled out in previous studies. Findings did not reveal any differences between the performance of dyslexic and control participants on eight versions of the visual recognition task. These findings suggest that pure dyslexic individuals do not present a reduced visual attention span.

  12. 78 FR 40393 - Drawbridge Operation Regulations; Piscataqua River, Portsmouth, NH and Kittery, ME

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-07-05

    ... of the lift span. This deviation is necessary to allow New Hampshire Department of Transportation's... deviation to facilitate necessary alignment and adjustments to the recently installed main lift span. Under...

  13. The capacity for ethical decisions: the relationship between working memory and ethical decision making.

    PubMed

    Martin, April; Bagdasarov, Zhanna; Connelly, Shane

    2015-04-01

    Although various models of ethical decision making (EDM) have implicitly called upon constructs governed by working memory capacity (WMC), a study examining this relationship specifically has not been conducted. Using a sense making framework of EDM, we examined the relationship between WMC and various sensemaking processes contributing to EDM. Participants completed an online assessment comprised of a demographic survey, intelligence test, various EDM measures, and the Automated Operation Span task to determine WMC. Results indicated that WMC accounted for unique variance above and beyond ethics education, exposure to ethical issues, and intelligence in several sensemaking processes. Additionally, a marginally significant effect of WMC was also found with reference to EDM. Individual differences in WMC appear likely to play an important role in the ethical decision-making process, and future researchers may wish to consider their potential influences.

  14. Dichotic and dichoptic digit perception in normal adults.

    PubMed

    Lawfield, Angela; McFarland, Dennis J; Cacace, Anthony T

    2011-06-01

    Verbally based dichotic-listening experiments and reproduction-mediated response-selection strategies have been used for over four decades to study perceptual/cognitive aspects of auditory information processing and make inferences about hemispheric asymmetries and language lateralization in the brain. Test procedures using dichotic digits have also been used to assess for disorders of auditory processing. However, with this application, limitations exist and paradigms need to be developed to improve specificity of the diagnosis. Use of matched tasks in multiple sensory modalities is a logical approach to address this issue. Herein, we use dichotic listening and dichoptic viewing of visually presented digits for making this comparison. To evaluate methodological issues involved in using matched tasks of dichotic listening and dichoptic viewing in normal adults. A multivariate assessment of the effects of modality (auditory vs. visual), digit-span length (1-3 pairs), response selection (recognition vs. reproduction), and ear/visual hemifield of presentation (left vs. right) on dichotic and dichoptic digit perception. Thirty adults (12 males, 18 females) ranging in age from 18 to 30 yr with normal hearing sensitivity and normal or corrected-to-normal visual acuity. A computerized, custom-designed program was used for all data collection and analysis. A four-way repeated measures analysis of variance (ANOVA) evaluated the effects of modality, digit-span length, response selection, and ear/visual field of presentation. The ANOVA revealed that performances on dichotic listening and dichoptic viewing tasks were dependent on complex interactions between modality, digit-span length, response selection, and ear/visual hemifield of presentation. Correlation analysis suggested a common effect on overall accuracy of performance but isolated only an auditory factor for a laterality index. The variables used in this experiment affected performances in the auditory modality to a greater extent than in the visual modality. The right-ear advantage observed in the dichotic-digits task was most evident when reproduction mediated response selection was used in conjunction with three-digit pairs. This effect implies that factors such as "speech related output mechanisms" and digit-span length (working memory) contribute to laterality effects in dichotic listening performance with traditional paradigms. Thus, the use of multiple-digit pairs to avoid ceiling effects and the application of verbal reproduction as a means of response selection may accentuate the role of nonperceptual factors in performance. Ideally, tests of perceptual abilities should be relatively free of such effects. American Academy of Audiology.

  15. Working memory training may increase working memory capacity but not fluid intelligence.

    PubMed

    Harrison, Tyler L; Shipstead, Zach; Hicks, Kenny L; Hambrick, David Z; Redick, Thomas S; Engle, Randall W

    2013-12-01

    Working memory is a critical element of complex cognition, particularly under conditions of distraction and interference. Measures of working memory capacity correlate positively with many measures of real-world cognition, including fluid intelligence. There have been numerous attempts to use training procedures to increase working memory capacity and thereby performance on the real-world tasks that rely on working memory capacity. In the study reported here, we demonstrated that training on complex working memory span tasks leads to improvement on similar tasks with different materials but that such training does not generalize to measures of fluid intelligence.

  16. Collections and user tools for utilization of persistent identifiers in cyberinfrastructures

    NASA Astrophysics Data System (ADS)

    Weigel, T.

    2014-12-01

    The main use of persistent identifiers (PIDs) for data objects has so far been for formal publication and citation purposes with a focus on long-term availability and trust. This core use case has now evolved and broadened to include basic data management tasks as identifiers are increasingly seen as a possible anchor element in the deluge of data for purposes of large-scale automation of tasks. The European Data Infrastructure (EUDAT) for instance uses PIDs in their back-end services and distinctly so for entities where the identifier may be more persistent than a resource with limited lifetime. Despite breaking with the traditional metaphor, this offers new opportunities for data management and end-user tools, but also requires a clear demonstrated benefit of value-added services because en masse identifier assignment does not come at zero costs. There are several obstacles to overcome when establishing identifiers at large scale. The administration of large numbers of identifiers can be cumbersome if they are treated in an isolated manner. Here, identifier collections can enable automated mass operations on groups of associated objects. Several use cases rely on base information that is rapidly available from the identifier systems without the need to retrieve objects, yet they will not work efficiently if the information is not consistently typed. Tools that span cyberinfrastructures and address scientific end-users unaware of the varying back-ends must overcome such obstacles. The Working Group on PID Information Types of the Research Data Alliance (RDA) has developed an interface specification and prototype to access and manipulate typed base information. Concrete prototypes for identifier collections exist as well. We will present some first data and provenance tracking tools that make extensive use of these recent developments and address different user needs that span from administrative tasks to individual end-user services with particular focus on data available from the Earth System Grid Federation (ESGF). We will compare the tools along their respective use cases with existing approaches and discuss benefits and limitations.

  17. 77 FR 25889 - Drawbridge Operation Regulations; Niantic River, Niantic, CT

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-05-02

    ... 20 nights to facilitate completion of work on machinery and the lift span. DATES: This deviation is... completion of machinery installation and lift span work at the new Niantic River RR Bridge. To facilitate...

  18. Comprehensive neurocognitive assessment of patients with anorexia nervosa.

    PubMed

    Phillipou, Andrea; Gurvich, Caroline; Castle, David Jonathan; Abel, Larry Allen; Rossell, Susan Lee

    2015-12-22

    To utilise a comprehensive cognitive battery to gain a better understanding of cognitive performance in anorexia nervosa (AN). Twenty-six individuals with AN and 27 healthy control participants matched for age, gender and premorbid intelligence, participated in the study. A standard cognitive battery, the Measurement and Treatment Research to Improve Cognition in Schizophrenia Consensus Cognitive Battery, was used to investigate performance on seven cognitive domains with the use of 10 different tasks: speed of processing [Brief Assessment Of Cognition In Schizophrenia: Symbol Coding, Category Fluency: Animal Naming (Fluency) and Trail Making Test: Part A], attention/vigilance [Continuous Performance Test - Identical Pairs (CPT-IP)], working memory [Wechsler Memory Scale (WMS(®)-III): Spatial Span, and Letter-Number Span (LNS)], verbal learning [Hopkins Verbal Learning Test - Revised], visual learning [Brief Visuospatial Memory Test - Revised], reasoning and problem solving [Neuropsychological Assessment Battery: Mazes], and social cognition [Mayer-Salovey-Caruso Emotional Intelligence Test: Managing Emotions]. Statistical analyses involved the use of multivariate and univariate analyses of variance. Analyses conducted on the cognitive domain scores revealed no overall significant difference between groups nor any interaction between group and domain score [F(1,45) = 0.73, P = 0.649]. Analyses conducted on each of the specific tasks within the cognitive domains revealed significantly slower reaction times for false alarm responses on the CPT-IP task in AN [F(1,51) = 12.80, P < 0.01, Cohen's d = 0.982] and a trend towards poorer performance in AN on the backward component of the WMS(®)-III Spatial Span task [F(1,51) = 5.88, P = 0.02, Cohen's d = -0.665]. The finding of slower reaction times of false alarm responses is, however, limited due to the small number of false alarm responses for either group. The findings are discussed in terms of poorer capacity to manipulate and process visuospatial material in AN.

  19. Negative emotional experiences arouse rumination and affect working memory capacity.

    PubMed

    Curci, Antonietta; Lanciano, Tiziana; Soleti, Emanuela; Rimé, Bernard

    2013-10-01

    Following an emotional experience, individuals are confronted with the persistence of ruminative thoughts that disturb the undertaking of other activities. In the present study, we experimentally tested the idea that experiencing a negative emotion triggers a ruminative process that drains working memory (WM) resources normally devoted to other tasks. Undergraduate participants of high versus low WM capacity were administered the operation-word memory span test (OSPAN) as a measure of availability of WM resources preceding and following the presentation of negative emotional versus neutral material. Rumination was assessed immediately after the second OSPAN session and at a 24-hr delay. Results showed that both the individual's WM capacity and the emotional valence of the material influenced WM performance and the persistence of ruminative thoughts. Following the experimental induction, rumination mediated the relationship between the negative emotional state and the concomitant WM performance. Based on these results, we argue that ruminative processes deplete WM resources, making them less available for concurrent tasks; in addition, rumination tends to persist over time. These findings have implications for the theoretical modeling of the long-term effects of emotions in both daily life and clinical contexts.

  20. Ordered short-term memory differs in signers and speakers: Implications for models of short-term memory

    PubMed Central

    Bavelier, Daphne; Newport, Elissa L.; Hall, Matt; Supalla, Ted; Boutla, Mrim

    2008-01-01

    Capacity limits in linguistic short-term memory (STM) are typically measured with forward span tasks in which participants are asked to recall lists of words in the order presented. Using such tasks, native signers of American Sign Language (ASL) exhibit smaller spans than native speakers (Boutla, Supalla, Newport, & Bavelier, 2004). Here, we test the hypothesis that this population difference reflects differences in the way speakers and signers maintain temporal order information in short-term memory. We show that native signers differ from speakers on measures of short-term memory that require maintenance of temporal order of the tested materials, but not on those in which temporal order is not required. In addition, we show that, in a recall task with free order, bilingual subjects are more likely to recall in temporal order when using English than ASL. We conclude that speakers and signers do share common short-term memory processes. However, whereas short-term memory for spoken English is predominantly organized in terms of temporal order, we argue that this dimension does not play as great a role in signers’ short-term memory. Other factors that may affect STM processes in signers are discussed. PMID:18083155

  1. Skilled Deaf Readers have an Enhanced Perceptual Span in Reading

    PubMed Central

    Bélanger, Nathalie N.; Slattery, Timothy J.; Mayberry, Rachel I.; Rayner, Keith

    2013-01-01

    Recent evidence suggests that deaf people have enhanced visual attention to simple stimuli in the parafovea in comparison to hearing people. Although a large part of reading involves processing the fixated words in foveal vision, readers also utilize information in parafoveal vision to pre-process upcoming words and decide where to look next. We investigated whether auditory deprivation affects low-level visual processing during reading, and compared the perceptual span of deaf signers who were skilled and less skilled readers to that of skilled hearing readers. Compared to hearing readers, deaf readers had a larger perceptual span than would be expected by their reading ability. These results provide the first evidence that deaf readers’ enhanced attentional allocation to the parafovea is used during a complex cognitive task such as reading. PMID:22683830

  2. Spelling difficulties in school-aged girls with attention-deficit/hyperactivity disorder: behavioral, psycholinguistic, cognitive, and graphomotor correlates.

    PubMed

    Åsberg Johnels, Jakob; Kopp, Svenny; Gillberg, Christopher

    2014-01-01

    Writing difficulties are common among children with attention-deficit/hyperactivity disorder (ADHD), but the nature of these difficulties has not been well studied. Here we relate behavioral, psycholinguistic, cognitive (memory/executive), and graphomotor measures to spelling skills in school-age girls with ADHD (n = 30) and an age-matched group of typically developed spellers (TYPSP, n = 35). When subdividing the ADHD group into those with poor (ADHDPSP, n = 19) and typical spelling (ADHDTYPSP, n = 11), the two subgroups did not differ with regard to inattentive or hyperactive-impulsive symptom severity according to parent or teacher ratings. Both ADHD subgroups also had equally severe difficulties in graphomotor control-handwriting and (parent ratings of) written expression as compared to the TYPSP group. In contrast, ADHDPSP had problems relative to ADHDTYPSP and TYPSP on phonological and orthographic recoding (choice tasks) and verbal memory (digit span) and were more likely to make commissions on a continuous performance task (CPT). Further analyses using the collapsed ADHD group showed that both digit span and the presence of CPT commissions predicted spelling performance independently of each other. Finally, results showed that phonological recoding skills mediated the association between digit span and spelling performance in ADHD. Theoretical and educational implications are discussed. © Hammill Institute on Disabilities 2012.

  3. Reduced Short-Term Memory Span in Aphasia and Susceptibility to Interference: Contribution of Material-Specific Maintenance Deficits

    PubMed Central

    Barde, Laura H.F.; Schwartz, Myrna F.; Chrysikou, Evangelia G.; Thompson-Schill, Sharon L.

    2010-01-01

    Semantic short-term memory (STM) deficits have been traditionally defined as an inability to maintain semantic representations over a delay (R. Martin, Shelton & Yaffee, 1994). Yet some patients with semantic STM deficits make numerous intrusions of items from previously presented lists, thus presenting an interesting paradox: Why should an inability to maintain semantic representations produce an increase in intrusions from earlier lists? In this study, we investigated the relationship between maintenance deficits and susceptibility to interference in a group of 20 aphasic patients characterized with weak semantic or weak phonological STM. Patients and matched control participants performed a modified item-recognition task designed to elicit semantic or phonological interference from list items located one, two, or three trials back (Hamilton & R. Martin, 2007). Controls demonstrated significant effects of interference in both versions of the task. Interference in patients was predicted by the type and severity of their STM deficit; that is, shorter semantic spans were associated with greater semantic interference and shorter phonological spans were associated with greater phonological interference. We interpret these results through a new perspective, the reactivation hypothesis, and we discuss their importance for accounts emphasizing the contribution of maintenance mechanisms for STM impairments in aphasia as well as susceptibility to interference. PMID:19925813

  4. Human Factors in Training

    NASA Technical Reports Server (NTRS)

    Barshi, Immanuel; Byrne, Vicky; Arsintescu, Lucia; Connell, Erin

    2010-01-01

    Future space missions will be significantly longer than current shuttle missions and new systems will be more complex than current systems. Increasing communication delays between crews and Earth-based support means that astronauts need to be prepared to handle the unexpected on their own. As crews become more autonomous, their potential span of control and required expertise must grow to match their autonomy. It is not possible to train for every eventuality ahead of time on the ground, or to maintain trained skills across long intervals of disuse. To adequately prepare NASA personnel for these challenges, new training approaches, methodologies, and tools are required. This research project aims at developing these training capabilities. By researching established training principles, examining future needs, and by using current practices in space flight training as test beds, both in Flight Controller and Crew Medical domains, this research project is mitigating program risks and generating templates and requirements to meet future training needs. Training efforts in Fiscal Year 09 (FY09) strongly focused on crew medical training, but also began exploring how Space Flight Resource Management training for Mission Operations Directorate (MOD) Flight Controllers could be integrated with systems training for optimal Mission Control Center (MCC) operations. The Training Task addresses Program risks that lie at the intersection of the following three risks identified by the Project: 1) Risk associated with poor task design; 2) Risk of error due to inadequate information; and 3) Risk associated with reduced safety and efficiency due to poor human factors design.

  5. Human Factors in Training

    NASA Technical Reports Server (NTRS)

    Barshi, Immanuel; Byrne, Vicky; Arsintescu, Lucia; Connell, Erin; Sandor, Aniko

    2009-01-01

    Future space missions will be significantly longer than current shuttle missions and new systems will be more complex than current systems. Increasing communication delays between crews and Earth-based support means that astronauts need to be prepared to handle the unexpected on their own. As crews become more autonomous, their potential span of control and required expertise must grow to match their autonomy. It is not possible to train for every eventuality ahead of time on the ground, or to maintain trained skills across long intervals of disuse. To adequately prepare NASA personnel for these challenges, new training approaches, methodologies, and tools are required. This research project aims at developing these training capabilities. By researching established training principles, examining future needs, and by using current practices in space flight training as test beds, both in Flight Controller and Crew Medical domains, this research project is mitigating program risks and generating templates and requirements to meet future training needs. Training efforts in Fiscal Year 08 (FY08) strongly focused on crew medical training, but also began exploring how Space Flight Resource Management training for Mission Operations Directorate (MOD) Flight Controllers could be integrated with systems training for optimal Mission Control Center (MCC) operations. The Training Task addresses Program risks that lie at the intersection of the following three risks identified by the Project: (1) Risk associated with poor task design (2) Risk of error due to inadequate information (3) Risk associated with reduced safety and efficiency due to poor human factors design

  6. Impaired letter-string processing in developmental dyslexia: what visual-to-phonology code mapping disorder?

    PubMed

    Valdois, Sylviane; Lassus-Sangosse, Delphine; Lobier, Muriel

    2012-05-01

    Poor parallel letter-string processing in developmental dyslexia was taken as evidence of poor visual attention (VA) span, that is, a limitation of visual attentional resources that affects multi-character processing. However, the use of letter stimuli in oral report tasks was challenged on its capacity to highlight a VA span disorder. In particular, report of poor letter/digit-string processing but preserved symbol-string processing was viewed as evidence of poor visual-to-phonology code mapping, in line with the phonological theory of developmental dyslexia. We assessed here the visual-to-phonological-code mapping disorder hypothesis. In Experiment 1, letter-string, digit-string and colour-string processing was assessed to disentangle a phonological versus visual familiarity account of the letter/digit versus symbol dissociation. Against a visual-to-phonological-code mapping disorder but in support of a familiarity account, results showed poor letter/digit-string processing but preserved colour-string processing in dyslexic children. In Experiment 2, two tasks of letter-string report were used, one of which was performed simultaneously to a high-taxing phonological task. Results show that dyslexic children are similarly impaired in letter-string report whether a concurrent phonological task is simultaneously performed or not. Taken together, these results provide strong evidence against a phonological account of poor letter-string processing in developmental dyslexia. Copyright © 2012 John Wiley & Sons, Ltd.

  7. Inhibitory Control and Working Memory in Post-Institutionalized Children

    PubMed Central

    Merz, Emily C.; McCall, Robert B.; Wright, Amanda J.; Luna, Beatriz

    2013-01-01

    Inhibitory control and working memory were examined in post-institutionalized (PI) children adopted into United States families from Russian institutions. The PI sample originated from institutions that were less severely depriving than those represented in previous studies and approximated the level of psychosocial deprivation, which is characterized by adequate physical resources but a lack of consistent and responsive caregiving. PI children (N=75; 29 male) ranged in age from 8–17 years (M=12.97; SD=3.03) and were grouped according to whether they were adopted after 14 months or before 9 months. A non-adopted comparison group (N=133; 65 male) ranged in age from 8–17 years (M=12.26; SD=2.75). PI children adopted after 14 months of age displayed poorer performance on the stop-signal and spatial span tasks relative to PI children adopted before 9 months of age after controlling for age at assessment. The two PI groups did not differ in their performance on a spatial self-ordered search task. Older-adopted PI children also showed poorer spatial span task performance compared to non-adopted children, but younger-adopted PI children did not. Task performance was significantly associated with parent-rated hyperactive-impulsive behavior in everyday contexts. These findings suggest that exposure to prolonged early institutional deprivation may be linked with inhibitory control and working memory difficulties years after adoption. PMID:23519375

  8. Intra-individual variability across cognitive task in drug-naïve pediatric patients with obsessive compulsive disorder.

    PubMed

    Okazaki, Kosuke; Yamamuro, Kazuhiko; Iida, Junzo; Ota, Toyosaku; Nakanishi, Yoko; Matsuura, Hiroki; Uratani, Mitsuhiro; Sawada, Satomi; Azechi, Takahiro; Kishimoto, Naoko; Kishimoto, Toshifumi

    2018-06-01

    Attention deficit is commonly observed in several psychiatric conditions. In particular, patients with attention deficit hyperactivity disorder exhibit not only attention deficit, but also intra-individual variability in response times (IIV-RT) during the performance of cognitive tasks related to attention span and sustained attention. Although obsessive compulsive disorder (OCD) is commonly observed across childhood, little is known about abnormalities in IIV-RT during the auditory odd-ball task, and how these changes relate to event-related potentials (ERPs) components. In the present study, we compared the ERPs of 15 adolescent and pediatric patients with OCD with 15 healthy age, sex, and IQ-matched controls. We found that tau of IIV-TR was not significantly different between the OCD group and controls, whereas the OCD group exhibited lower mu and sigma compared to controls. Furthermore, we revealed that P300 amplitude was significantly attenuated in the OCD group at Fz, C3, and C4, compared with controls. The present study thereby provided the first evidence that individuals with pediatric or adolescent OCD exhibit lower variability in reaction time in IIV-RT during an auditory odd-ball task than controls. These results suggest that there are no impairments in attention span and sustained attention in pediatric and adolescent patients with OCD. Copyright © 2018 Elsevier B.V. All rights reserved.

  9. Hydrocortisone infusion exerts dose- and sex-dependent effects on attention to emotional stimuli.

    PubMed

    Breitberg, Alaina; Drevets, Wayne C; Wood, Suzanne E; Mah, Linda; Schulkin, Jay; Sahakian, Barbara J; Erickson, Kristine

    2013-03-01

    Glucocorticoid administration has been shown to exert complex effects on cognitive and emotional processing. In the current study we investigated the effects of glucocorticoid administration on attention towards emotional words, using an Affective Go/No-go task on which healthy humans have shown an attentional bias towards positive as compared to negative words. Healthy volunteers received placebo and either low-dose (0.15mg/kg) or high-dose (0.45mg/kg) hydrocortisone intravenously during two separate visits in a double-blind, randomized design. Seventy-five minutes post-infusion, the subjects performed tests of attention (Rapid Visual Information Processing [RVIP]), spatial working memory (Spatial Span) and emotional processing (Affective Go/No-go task [AGNG]). On the attention task, performance was impaired under both hydrocortisone doses relative to placebo, though the effect on error rate was not significant after controlling for age; Spatial Span performance was unaffected by hydrocortisone administration. On the AGNG task, relative to the placebo condition the low-dose hydrocortisone infusion decreased response time to emotional words while high-dose hydrocortisone increased response time. In the females specifically, both high and low dose hydrocortisone administration attenuated the normal attentional bias toward positively valenced words. These data suggest that, in healthy women, the modulation of attention by the emotional salience of stimuli is influenced by glucocorticoid hormone concentrations. Copyright © 2012 Elsevier Inc. All rights reserved.

  10. Nuclear plants gain integrated information systems

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Villavicencio-Ramirez, A.; Rodriquez-Alvarez, J.M.

    1994-10-01

    With the objective of simplifying the complex mesh of computing devices employed within nuclear power plants, modern technology and integration techniques are being used to form centralized (but backed up) databases and distributed processing and display networks. Benefits are immediate as a result of the integration and the use of standards. The use of a unique data acquisition and database subsystem optimizes the high costs of engineering, as this task is done only once for the life span of the system. This also contributes towards a uniform user interface and allows for graceful expansion and maintenance. This article features anmore » integrated information system, Sistema Integral de Informacion de Proceso (SIIP). The development of this system enabled the Laguna Verde Nuclear Power plant to fully use the already existing universe of signals and its related engineering during all plant conditions, namely, start up, normal operation, transient analysis, and emergency operation. Integrated systems offer many advantages over segregated systems, and this experience should benefit similar development efforts in other electric power utilities, not only for nuclear but also for other types of generating plants.« less

  11. 78 FR 9588 - Drawbridge Operation Regulations; Saugus River, Lynn and Revere, MA

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-02-11

    ... scaffolding be attached to the bascule lift span to access work area. DATES: This deviation is effective from... facilitate rehabilitation of the bridge towers that requires scaffolding be attached to the bascule lift span...

  12. Executive functions as endophenotypes in ADHD: evidence from the Cambridge Neuropsychological Test Battery (CANTAB).

    PubMed

    Gau, Susan Shur-Fen; Shang, Chi-Yung

    2010-07-01

    Little is known about executive functions among unaffected siblings of children with attention deficit/hyperactivity disorder (ADHD), and there is lack of such information from non-Western countries. We examined verbal and nonverbal executive functions in adolescents with ADHD, unaffected siblings and controls to test whether executive functions could be potential endophenotypes for ADHD. We assessed 279 adolescents (age range: 11-17 years) with a childhood diagnosis of DSM-IV ADHD, 136 biological siblings (108 unaffected, 79.4%), and 173 unaffected controls by using psychiatric interviews, the Wechsler Intelligence Scale for Children - 3rd edition (WISC-III), including digit spans, and the tasks involving executive functions of the Cambridge Neuropsychological Test Automated Battery (CANTAB): Intra-dimensional/Extra-dimensional Shifts (IED), Spatial Span (SSP), Spatial Working Memory (SWM), and Stockings of Cambridge (SOC). Compared with the controls, adolescents with ADHD and unaffected siblings had a significantly shorter backward digit span, more extra-dimensional shift errors in the IED, shorter spatial span length in the SSP, more total errors and poorer strategy use in the SWM, and fewer problems solved in the minimum number of moves and shorter initial thinking time in the SOC. The magnitudes of the differences in the SWM and SOC increased with increased task difficulties. In general, neither persistent ADHD nor comorbidity was associated with increased deficits in executive functions among adolescents with ADHD. The lack of much difference in executive dysfunctions between unaffected siblings and ADHD adolescents suggests that executive dysfunctions may be useful cognitive endophenotypes for ADHD genetic studies.

  13. Stable and Dynamic Coding for Working Memory in Primate Prefrontal Cortex

    PubMed Central

    Watanabe, Kei; Funahashi, Shintaro; Stokes, Mark G.

    2017-01-01

    Working memory (WM) provides the stability necessary for high-level cognition. Influential theories typically assume that WM depends on the persistence of stable neural representations, yet increasing evidence suggests that neural states are highly dynamic. Here we apply multivariate pattern analysis to explore the population dynamics in primate lateral prefrontal cortex (PFC) during three variants of the classic memory-guided saccade task (recorded in four animals). We observed the hallmark of dynamic population coding across key phases of a working memory task: sensory processing, memory encoding, and response execution. Throughout both these dynamic epochs and the memory delay period, however, the neural representational geometry remained stable. We identified two characteristics that jointly explain these dynamics: (1) time-varying changes in the subpopulation of neurons coding for task variables (i.e., dynamic subpopulations); and (2) time-varying selectivity within neurons (i.e., dynamic selectivity). These results indicate that even in a very simple memory-guided saccade task, PFC neurons display complex dynamics to support stable representations for WM. SIGNIFICANCE STATEMENT Flexible, intelligent behavior requires the maintenance and manipulation of incoming information over various time spans. For short time spans, this faculty is labeled “working memory” (WM). Dominant models propose that WM is maintained by stable, persistent patterns of neural activity in prefrontal cortex (PFC). However, recent evidence suggests that neural activity in PFC is dynamic, even while the contents of WM remain stably represented. Here, we explored the neural dynamics in PFC during a memory-guided saccade task. We found evidence for dynamic population coding in various task epochs, despite striking stability in the neural representational geometry of WM. Furthermore, we identified two distinct cellular mechanisms that contribute to dynamic population coding. PMID:28559375

  14. Performance Assessment Examples from the Quality Performance Assessment Network

    ERIC Educational Resources Information Center

    Kuriacose, Christina

    2017-01-01

    In this brief article, Christina Kuriacose provides four sample performance assessments. Spanning grade levels, these assessments are strong examples of teacher-developed performance assessments from schools within the Center for Collaborative Education's Quality Performance Assessment network. These performance tasks demonstrate the pedagogical…

  15. Marital Therapy with Older Couples.

    ERIC Educational Resources Information Center

    Qualls, Sara Honn

    1993-01-01

    Presents basic information concerning normal aging that therapists need to understand sources of conflict and distress in older or caregiving couples. Describes unique aspects of assessment and intervention with older couples. Examines marital satisfaction across life span, including factors that alter marital functioning, developmental tasks and…

  16. Annual Report Nucelar Energy Research and Development Program Nuclear Energy Research Initiative

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hively, LM

    2003-02-13

    NERI Project No.2000-0109 began in August 2000 and has three tasks. The first project year addressed Task 1, namely development of nonlinear prognostication for critical equipment in nuclear power facilities. That work is described in the first year's annual report (ORNLTM-2001/195). The current (second) project year (FY02) addresses Task 2, while the third project year will address Tasks 2-3. This report describes the work for the second project year, spanning August 2001 through August 2002, including status of the tasks, issues and concerns, cost performance, and status summary of tasks. The objective of the second project year's work is amore » compelling demonstration of the nonlinear prognostication algorithm using much more data. The guidance from Dr. Madeline Feltus (DOE/NE-20) is that it would be preferable to show forewarning of failure for different kinds of nuclear-grade equipment, as opposed to many different failure modes from one piece of equipment. Long-term monitoring of operational utility equipment is possible in principle, but is not practically feasible for the following reason. Time and funding constraints for this project do not allow us to monitor the many machines (thousands) that will be necessary to obtain even a few failure sequences, due to low failure rates (<10{sup -3}/year) in the operational environment. Moreover, the ONLY way to guarantee a controlled failure sequence is to seed progressively larger faults in the equipment or to overload the equipment for accelerated tests. Both of these approaches are infeasible for operational utility machinery, but are straight-forward in a test environment. Our subcontractor has provided such test sequences. Thus, we have revised Tasks 2.1-2.4 to analyze archival test data from such tests. The second phase of our work involves validation of the nonlinear prognostication over the second and third years of the proposed work. Recognizing the inherent limitations outlined in the previous paragraph, Dr. Feltus urged Oak Ridge National Laboratory (ORNL) to contact other researchers for additional data from other test equipment. Consequently, we have revised the work plan for Tasks 2.1-2.2, with corresponding changes to the work plan as shown in the Status Summary of NERI Tasks. The revised tasks are as follows: Task 2.1--ORNL will obtain test data from a subcontractor and other researchers for various test equipment. This task includes development of a test plan or a description of the historical testing, as appropriate: test facility, equipment to be tested, choice of failure mode(s), testing protocol, data acquisition equipment, and resulting data from the test sequence. ORNL will analyze this data for quality, and subsequently via the nonlinear paradigm for prognostication. Task 2.2--ORNL will evaluate the prognostication capability of the nonlinear paradigm. The comparison metrics for reliability of the predictions will include the true positives, true negatives, and the forewarning times. Task 2.3--ORNL will improve the nonlinear paradigm as appropriate, in accord with the results of Tasks 2.1-2.2, to maximize the rate of true positive and true negative indications of failure. Maximal forewarning time is also highly desirable. Task 2.4--ORNL will develop advanced algorithms for the phase-space distribution function (PS-DF) pattern change recognition, based on the results of Task 2.3. This implementation will provide a capability for automated prognostication, as part of the maintenance decision-making. Appendix A provides a detailed description of the analysis methods, which include conventional statistics, traditional nonlinear measures, and ORNL's patented nonlinear PSDM. The body of this report focuses on results of this analysis.« less

  17. Sex-related differences in attention and memory.

    PubMed

    Solianik, Rima; Brazaitis, Marius; Skurvydas, Albertas

    2016-01-01

    The sex differences and similarities in cognitive abilities is a continuing topic of major interest. Besides, the influences of trends over time and possible effects of sex steroid and assessment time on cognition have expanded the necessity to re-evaluate differences between men and women. Therefore, the aim of this study was to compare cognitive performance between men and women in a strongly controlled experiment. In total, 28 men and 25 women were investigated. Variables of body temperature and heart rate were assessed. A cognitive test battery was used to assess attention (visual search, unpredictable task switching as well as complex visual search and predictable task switching tests) and memory (forced visual memory, forward digit span and free recall test). The differences in heart rate and body temperatures between men and women were not significant. There were no differences in the mean values of attention and memory abilities between men and women. Coefficients of variation of unpredictable task switching response and forward digit span were lower (P<0.05) in men. Coefficients of variation positively correlated (P<0.05) with attention task incorrect response and negatively correlated (P<0.05) with correct answers in the memory task. Current study showed no sex differences in the mean values of cognition, whereas higher intra-individual variability of short-term memory and attention switching was identified in women, indicating that their performance was lower on these cognitive abilities. Copyright © 2016 The Lithuanian University of Health Sciences. Production and hosting by Elsevier Urban & Partner Sp. z o.o. All rights reserved.

  18. Age-Related Differences in Multiple Task Monitoring

    PubMed Central

    Todorov, Ivo; Del Missier, Fabio; Mäntylä, Timo

    2014-01-01

    Coordinating multiple tasks with narrow deadlines is particularly challenging for older adults because of age related decline in cognitive control functions. We tested the hypothesis that multiple task performance reflects age- and gender-related differences in executive functioning and spatial ability. Young and older adults completed a multitasking session with four monitoring tasks as well as separate tasks measuring executive functioning and spatial ability. For both age groups, men exceeded women in multitasking, measured as monitoring accuracy. Individual differences in executive functioning and spatial ability were independent predictors of young adults' monitoring accuracy, but only spatial ability was related to sex differences. For older adults, age and executive functioning, but not spatial ability, predicted multitasking performance. These results suggest that executive functions contribute to multiple task performance across the adult life span and that reliance on spatial skills for coordinating deadlines is modulated by age. PMID:25215609

  19. Age-related differences in multiple task monitoring.

    PubMed

    Todorov, Ivo; Del Missier, Fabio; Mäntylä, Timo

    2014-01-01

    Coordinating multiple tasks with narrow deadlines is particularly challenging for older adults because of age related decline in cognitive control functions. We tested the hypothesis that multiple task performance reflects age- and gender-related differences in executive functioning and spatial ability. Young and older adults completed a multitasking session with four monitoring tasks as well as separate tasks measuring executive functioning and spatial ability. For both age groups, men exceeded women in multitasking, measured as monitoring accuracy. Individual differences in executive functioning and spatial ability were independent predictors of young adults' monitoring accuracy, but only spatial ability was related to sex differences. For older adults, age and executive functioning, but not spatial ability, predicted multitasking performance. These results suggest that executive functions contribute to multiple task performance across the adult life span and that reliance on spatial skills for coordinating deadlines is modulated by age.

  20. Task experience and children’s working memory performance: A perspective from recall timing

    PubMed Central

    Towse, John N.; Cowan, Nelson; Horton, Neil J.; Whytock, Shealagh

    2008-01-01

    Working memory is an important theoretical construct among children, and measures of its capacity predict a range of cognitive skills and abilities. Data from 9-and 11-year-old children illustrate how a chronometric analysis of recall can complement and elaborate recall accuracy in advancing our understanding of working memory. A reading span task was completed by 130 children, 75 of whom were tested on two occasions, with sequence length either increasing or decreasing during test administration. Substantial pauses occur during participants’ recall sequences and they represent consistent performance traits over time, whilst also varying with recall circumstances and task history. Recall pauses help to predict reading and number skills, alongside as well as separate from levels of recall accuracy. The task demands of working memory change as a function of task experience, with a combination of accuracy and response timing in novel task situations being the strongest predictor of cognitive attainment. PMID:18473637

  1. Automation of the novel object recognition task for use in adolescent rats

    PubMed Central

    Silvers, Janelle M.; Harrod, Steven B.; Mactutus, Charles F.; Booze, Rosemarie M.

    2010-01-01

    The novel object recognition task is gaining popularity for its ability to test a complex behavior which relies on the integrity of memory and attention systems without placing undue stress upon the animal. While the task places few requirements upon the animal, it traditionally requires the experimenter to observe the test phase directly and record behavior. This approach can severely limit the number of subjects which can be tested in a reasonable period of time, as training and testing occur on the same day and span several hours. The current study was designed to test the feasibility of automation of this task for adolescent rats using standard activity chambers, with the goals of increased objectivity, flexibility, and throughput of subjects. PMID:17719091

  2. Balanced bifrontal transcranial direct current stimulation enhances working memory in adults with high-functioning autism: a sham-controlled crossover study.

    PubMed

    van Steenburgh, J Jason; Varvaris, Mark; Schretlen, David J; Vannorsdall, Tracy D; Gordon, Barry

    2017-01-01

    Working memory (WM) often is impaired in autism spectrum disorder (ASD). Such impairment may underlie core deficits in cognition and social functioning. Transcranial direct current stimulation (tDCS) has been shown to enhance WM in both healthy adults and clinical populations, but its efficacy in ASD is unknown. We predicted that bifrontal tDCS would improve WM performances of adults with high-functioning autism during active stimulation compared to sham stimulation and that such enhancement would generalize to an untrained task. Twelve adults with high-functioning ASD engaged in a battery of WM tasks that included backward spatial span, backward digit span, spatial n -back and letter n -back. While engaged, 40 min of 1.5 mA bifrontal stimulation was applied over the left and the right dorsolateral prefrontal cortices (DLPFC). Using a single-blind crossover design, each participant received left anodal/right cathodal stimulation, right anodal/left cathodal stimulation, or sham stimulation, in randomized counterbalanced order on three separate days. Following tDCS, participants again engaged in letter and spatial n -back tasks before taking the Brief Test of Attention (BTA). We used repeated-measures ANOVA to compare overall performance on the WM battery as measured by a composite of z -scores for all five measures. Post hoc ANOVAs, t tests, Friedman's tests, and Wilcoxon signed-rank tests were used to measure the online and offline effects of tDCS and to assess performances on individual measures. Compared to sham stimulation, both left DLPFC anodal stimulation ( t 11  = 5.4, p  = 0.0002) and right DLPFC anodal stimulation ( t 11  = 3.57, p  = 0.004) improved overall WM performance. Left anodal stimulation ( t 11  = 3.9, p  = 0.003) and right anodal stimulation ( t 11  = 2.7, p  = 0.019) enhanced performances during stimulation. Enhancement transferred to an untrained task 50 min after right anodal stimulation (z 11  = 2.263, p  = 0.024). The tasks that showed the largest effects of active stimulation were spatial span backward ( z 11  = 2.39, p  = 0.017) and BTA ( z 11  = 2.263, p  = 0.024). In adults with high-functioning ASD, active bifrontal tDCS given during WM tasks appears to improve performance. TDCS benefits also transferred to an untrained task completed shortly after stimulation. These results suggest that tDCS can improve WM task performance and could reduce some core deficits of autism. NCT01602263.

  3. Effects of visual span on reading speed and parafoveal processing in eye movements during sentence reading.

    PubMed

    Risse, Sarah

    2014-07-15

    The visual span (or ‘‘uncrowded window’’), which limits the sensory information on each fixation, has been shown to determine reading speed in tasks involving rapid serial visual presentation of single words. The present study investigated whether this is also true for fixation durations during sentence reading when all words are presented at the same time and parafoveal preview of words prior to fixation typically reduces later word-recognition times. If so, a larger visual span may allow more efficient parafoveal processing and thus faster reading. In order to test this hypothesis, visual span profiles (VSPs) were collected from 60 participants and related to data from an eye-tracking reading experiment. The results confirmed a positive relationship between the readers’ VSPs and fixation-based reading speed. However, this relationship was not determined by parafoveal processing. There was no evidence that individual differences in VSPs predicted differences in parafoveal preview benefit. Nevertheless, preview benefit correlated with reading speed, suggesting an independent effect on oculomotor control during reading. In summary, the present results indicate a more complex relationship between the visual span, parafoveal processing, and reading speed than initially assumed. © 2014 ARVO.

  4. A class of vertex-edge-growth small-world network models having scale-free, self-similar and hierarchical characters

    NASA Astrophysics Data System (ADS)

    Ma, Fei; Su, Jing; Hao, Yongxing; Yao, Bing; Yan, Guanghui

    2018-02-01

    The problem of uncovering the internal operating function of network models is intriguing, demanded and attractive in researches of complex networks. Notice that, in the past two decades, a great number of artificial models are built to try to answer the above mentioned task. Based on the different growth ways, these previous models can be divided into two categories, one type, possessing the preferential attachment, follows a power-law P(k) ∼k-γ, 2 < γ < 3. The other has exponential-scaling feature, P(k) ∼α-k. However, there are no models containing above two kinds of growth ways to be presented, even the study of interconnection between these two growth manners in the same model is lacking. Hence, in this paper, we construct a class of planar and self-similar graphs motivated from a new attachment way, vertex-edge-growth network-operation, more precisely, the couple of both them. We report that this model is sparse, small world and hierarchical. And then, not only is scale-free feature in our model, but also lies the degree parameter γ(≈ 3 . 242) out the typical range. Note that, we suggest that the coexistence of multiple vertex growth ways will have a prominent effect on the power-law parameter γ, and the preferential attachment plays a dominate role on the development of networks over time. At the end of this paper, we obtain an exact analytical expression for the total number of spanning trees of models and also capture spanning trees entropy which we have compared with those of their corresponding component elements.

  5. Discerning measures of conscious brain processes associated with superior early motor performance: Capacity, coactivation, and character.

    PubMed

    van Duijn, Tina; Buszard, Tim; Hoskens, Merel C J; Masters, Rich S W

    2017-01-01

    This study explored the relationship between working memory (WM) capacity, corticocortical communication (EEG coherence), and propensity for conscious control of movement during the performance of a complex far-aiming task. We were specifically interested in the role of these variables in predicting motor performance by novices. Forty-eight participants completed (a) an assessment of WM capacity (an adapted Rotation Span task), (b) a questionnaire that assessed the propensity to consciously control movement (the Movement Specific Reinvestment Scale), and (c) a hockey push-pass task. The hockey push-pass task was performed in a single task (movement only) condition and a combined task (movement plus decision) condition. Electroencephalography (EEG) was used to examine brain activity during the single task. WM capacity best predicted single task performance. WM capacity in combination with T8-Fz coherence (between the visuospatial and motor regions of the brain) best predicted combined task performance. We discuss the implied roles of visuospatial information processing capacity, neural coactivation, and propensity for conscious processing during performance of complex motor tasks. © 2017 Elsevier B.V. All rights reserved.

  6. Simulator study of flight characteristics of several large, dissimilar, cargo transport airplanes during approach and landing

    NASA Technical Reports Server (NTRS)

    Grantham, W. D.; Smith, P. M.; Deal, P. L.; Neely, W. R., Jr.

    1984-01-01

    A six-degree-of-freedom, ground based simulator study is conducted to evaluate the low-speed flight characteristics of four dissimilar cargo transport airplanes. These characteristics are compared with those of a large, present-day (reference) transport configuration similar to the Lockheed C-5A airplane. The four very large transport concepts evaluated consist of single-fuselage, twin-fuselage, triple-fuselage, and span-loader configurations. The primary piloting task is the approach and landing operation. The results of his study indicate that all four concepts evaluated have unsatisfactory longitudinal and lateral directional low speed flight characteristics and that considerable stability and control augmentation would be required to improve these characteristics (handling qualities) to a satisfactory level. Through the use of rate command/attitude hold augmentation in the pitch and roll axes, and the use of several turn-coordination features, the handling qualities of all four large transports simulated are improved appreciably.

  7. Effects of Extreme Sleep Deprivation on Human Performance

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Tuan Tran; Kimberly R. Raddatz; Elizabeth T. Cady

    Sleep is a fundamental recuperative process for the nervous system. Disruption of this homeostatic drive can lead to severe impairments of the operator’s ability to perceive, recognize, and respond to emergencies and/or unanticipated events, putting the operator at risk. Therefore, establishing a comprehensive understanding of how sleep deprivation influences human performance is essential in order to counter fatigue or to develop mitigation strategies. The goal of the present study was to examine the psychological effects of prolonged sleep deprivation (approx. 75 hrs) over a four-day span on a general aviation pilot flying a fixed-based flight simulator. During the study, amore » series of tasks were employed every four hours in order to examine the pilot’s perceptual and higher level cognitive abilities. Overall, results suggest that the majority of cognitive and perceptual degradation occurs between 30-40 hours into the flight. Limitations and future research directions are also discussed.« less

  8. Working memory training using mental calculation impacts regional gray matter of the frontal and parietal regions.

    PubMed

    Takeuchi, Hikaru; Taki, Yasuyuki; Sassa, Yuko; Hashizume, Hiroshi; Sekiguchi, Atsushi; Fukushima, Ai; Kawashima, Ryuta

    2011-01-01

    Training working memory (WM) improves performance on untrained cognitive tasks and alters functional activity. However, WM training's effects on gray matter morphology and a wide range of cognitive tasks are still unknown. We investigated this issue using voxel-based morphometry (VBM), various psychological measures, such as non-trained WM tasks and a creativity task, and intensive adaptive training of WM using mental calculations (IATWMMC), all of which are typical WM tasks. IATWMMC was associated with reduced regional gray matter volume in the bilateral fronto-parietal regions and the left superior temporal gyrus. It improved verbal letter span and complex arithmetic ability, but deteriorated creativity. These results confirm the training-induced plasticity in psychological mechanisms and the plasticity of gray matter structures in regions that have been assumed to be under strong genetic control.

  9. Infants' development of object permanence: a refined methodology and new evidence of Piaget's hypothesized ordinality.

    PubMed

    Kramer, J A; Hill, K T; Cohen, L B

    1975-03-01

    To investigate Piaget's theory of object concept development, a series of 6 tasks was administered in a combined longitudinal/cross-sectional design incorporating a number of methodological controls. The tasks spanned the entire sensorimotor period and included single versus sequential displacements combined with visible or invisible hidings. 36 infants from 5 to 32 months of age at initial testing were drawn equally from day-care and home settings. All infants received the 6 tasks during each of 3 testing sessions over a 6-month period. Clear evidence was obtained for task ordinality as proposed by Piaget, with ordinality coefficients ranging from .71 to .82 for the 3 testing sessions. Performance changes across the 3 sessions were also ordinal in 80% of the cases. Expected age, task, and session effects and accompanying interactions were also obtained.

  10. Using Stimulant Drugs in the Classroom.

    ERIC Educational Resources Information Center

    Barkley, Russell A.

    1979-01-01

    Research is reviewed on the effects of stimulant drugs on the classroom behavior and academic achievement of hyperactive children. Results indicate that stimulant drugs do not appreciably improve academic achievement, but are effective in improving attention span, on-task behavior, activity level, and disruptive behavior. (Author/MH)

  11. Video game-based exercises for balance rehabilitation: a single-subject design.

    PubMed

    Betker, Aimee L; Szturm, Tony; Moussavi, Zahra K; Nett, Cristabel

    2006-08-01

    To investigate whether coupling foot center of pressure (COP)-controlled video games to standing balance exercises will improve dynamic balance control and to determine whether the motivational and challenging aspects of the video games would increase a subject's desire to perform the exercises and complete the rehabilitation process. Case study, pre- and postexercise. University hospital outpatient clinic. A young adult with excised cerebellar tumor, 1 middle-aged adult with single right cerebrovascular accident, and 1 middle-aged adult with traumatic brain injury. A COP-controlled, video game-based exercise system. The following were calculated during 12 different tasks: the number of falls, range of COP excursion, and COP path length. Postexercise, subjects exhibited a lower fall count, decreased COP excursion limits for some tasks, increased practice volume, and increased attention span during training. The COP-controlled video game-based exercise regime motivated subjects to increase their practice volume and attention span during training. This in turn improved subjects' dynamic balance control.

  12. Maintenance of item and order information in verbal working memory.

    PubMed

    Camos, Valérie; Lagner, Prune; Loaiza, Vanessa M

    2017-09-01

    Although verbal recall of item and order information is well-researched in short-term memory paradigms, there is relatively little research concerning item and order recall from working memory. The following study examined whether manipulating the opportunity for attentional refreshing and articulatory rehearsal in a complex span task differently affected the recall of item- and order-specific information of the memoranda. Five experiments varied the opportunity for articulatory rehearsal and attentional refreshing in a complex span task, but the type of recall was manipulated between experiments (item and order, order only, and item only recall). The results showed that impairing attentional refreshing and articulatory rehearsal similarly affected recall regardless of whether the scoring procedure (Experiments 1 and 4) or recall requirements (Experiments 2, 3, and 5) reflected item- or order-specific recall. This implies that both mechanisms sustain the maintenance of item and order information, and suggests that the common cumulative functioning of these two mechanisms to maintain items could be at the root of order maintenance.

  13. Intelligence as the efficiency of cue-driven retrieval from secondary memory.

    PubMed

    Liesefeld, Heinrich René; Hoffmann, Eugenia; Wentura, Dirk

    2016-01-01

    Complex-span (working-memory-capacity) tasks are among the most successful predictors of intelligence. One important contributor to this relationship is the ability to efficiently employ cues for the retrieval from secondary memory. Presumably, intelligent individuals can considerably restrict their memory search sets by using such cues and can thereby improve recall performance. We here test this assumption by experimentally manipulating the validity of retrieval cues. When memoranda are drawn from the same semantic category on two successive trials of a verbal complex-span task, the category is a very strong retrieval cue on its first occurrence (strong-cue trial) but loses some of its validity on its second occurrence (weak-cue trial). If intelligent individuals make better use of semantic categories as retrieval cues, their recall accuracy suffers more from this loss of cue validity. Accordingly, our results show that less variance in intelligence is explained by recall accuracy on weak-cue compared with strong-cue trials.

  14. Signed language working memory capacity of signed language interpreters and deaf signers.

    PubMed

    Wang, Jihong; Napier, Jemina

    2013-04-01

    This study investigated the effects of hearing status and age of signed language acquisition on signed language working memory capacity. Professional Auslan (Australian sign language)/English interpreters (hearing native signers and hearing nonnative signers) and deaf Auslan signers (deaf native signers and deaf nonnative signers) completed an Auslan working memory (WM) span task. The results revealed that the hearing signers (i.e., the professional interpreters) significantly outperformed the deaf signers on the Auslan WM span task. However, the results showed no significant differences between the native signers and the nonnative signers in their Auslan working memory capacity. Furthermore, there was no significant interaction between hearing status and age of signed language acquisition. Additionally, the study found no significant differences between the deaf native signers (adults) and the deaf nonnative signers (adults) in their Auslan working memory capacity. The findings are discussed in relation to the participants' memory strategies and their early language experience. The findings present challenges for WM theories.

  15. Enhancing Cognition with Video Games: A Multiple Game Training Study

    PubMed Central

    Oei, Adam C.; Patterson, Michael D.

    2013-01-01

    Background Previous evidence points to a causal link between playing action video games and enhanced cognition and perception. However, benefits of playing other video games are under-investigated. We examined whether playing non-action games also improves cognition. Hence, we compared transfer effects of an action and other non-action types that required different cognitive demands. Methodology/Principal Findings We instructed 5 groups of non-gamer participants to play one game each on a mobile device (iPhone/iPod Touch) for one hour a day/five days a week over four weeks (20 hours). Games included action, spatial memory, match-3, hidden- object, and an agent-based life simulation. Participants performed four behavioral tasks before and after video game training to assess for transfer effects. Tasks included an attentional blink task, a spatial memory and visual search dual task, a visual filter memory task to assess for multiple object tracking and cognitive control, as well as a complex verbal span task. Action game playing eliminated attentional blink and improved cognitive control and multiple-object tracking. Match-3, spatial memory and hidden object games improved visual search performance while the latter two also improved spatial working memory. Complex verbal span improved after match-3 and action game training. Conclusion/Significance Cognitive improvements were not limited to action game training alone and different games enhanced different aspects of cognition. We conclude that training specific cognitive abilities frequently in a video game improves performance in tasks that share common underlying demands. Overall, these results suggest that many video game-related cognitive improvements may not be due to training of general broad cognitive systems such as executive attentional control, but instead due to frequent utilization of specific cognitive processes during game play. Thus, many video game training related improvements to cognition may be attributed to near-transfer effects. PMID:23516504

  16. Indicators of suboptimal performance embedded in the Wechsler Memory Scale-Fourth Edition (WMS-IV).

    PubMed

    Bouman, Zita; Hendriks, Marc P H; Schmand, Ben A; Kessels, Roy P C; Aldenkamp, Albert P

    2016-01-01

    Recognition and visual working memory tasks from the Wechsler Memory Scale-Fourth Edition (WMS-IV) have previously been documented as useful indicators for suboptimal performance. The present study examined the clinical utility of the Dutch version of the WMS-IV (WMS-IV-NL) for the identification of suboptimal performance using an analogue study design. The patient group consisted of 59 mixed-etiology patients; the experimental malingerers were 50 healthy individuals who were asked to simulate cognitive impairment as a result of a traumatic brain injury; the last group consisted of 50 healthy controls who were instructed to put forth full effort. Experimental malingerers performed significantly lower on all WMS-IV-NL tasks than did the patients and healthy controls. A binary logistic regression analysis was performed on the experimental malingerers and the patients. The first model contained the visual working memory subtests (Spatial Addition and Symbol Span) and the recognition tasks of the following subtests: Logical Memory, Verbal Paired Associates, Designs, Visual Reproduction. The results showed an overall classification rate of 78.4%, and only Spatial Addition explained a significant amount of variation (p < .001). Subsequent logistic regression analysis and receiver operating characteristic (ROC) analysis supported the discriminatory power of the subtest Spatial Addition. A scaled score cutoff of <4 produced 93% specificity and 52% sensitivity for detection of suboptimal performance. The WMS-IV-NL Spatial Addition subtest may provide clinically useful information for the detection of suboptimal performance.

  17. Portable wireless neurofeedback system of EEG alpha rhythm enhances memory.

    PubMed

    Wei, Ting-Ying; Chang, Da-Wei; Liu, You-De; Liu, Chen-Wei; Young, Chung-Ping; Liang, Sheng-Fu; Shaw, Fu-Zen

    2017-11-13

    Effect of neurofeedback training (NFT) on enhancement of cognitive function or amelioration of clinical symptoms is inconclusive. The trainability of brain rhythm using a neurofeedback system is uncertainty because various experimental designs are used in previous studies. The current study aimed to develop a portable wireless NFT system for alpha rhythm and to validate effect of the NFT system on memory with a sham-controlled group. The proposed system contained an EEG signal analysis device and a smartphone with wireless Bluetooth low-energy technology. Instantaneous 1-s EEG power and contiguous 5-min EEG power throughout the training were developed as feedback information. The training performance and its progression were kept to boost usability of our device. Participants were blinded and randomly assigned into either the control group receiving random 4-Hz power or Alpha group receiving 8-12-Hz power. Working memory and episodic memory were assessed by the backward digital span task and word-pair task, respectively. The portable neurofeedback system had advantages of a tiny size and long-term recording and demonstrated trainability of alpha rhythm in terms of significant increase of power and duration of 8-12 Hz. Moreover, accuracies of the backward digital span task and word-pair task showed significant enhancement in the Alpha group after training compared to the control group. Our tiny portable device demonstrated success trainability of alpha rhythm and enhanced two kinds of memories. The present study suggest that the portable neurofeedback system provides an alternative intervention for memory enhancement.

  18. The role of age, working memory, and response inhibition in deviance distraction: A cross-sectional study.

    PubMed

    Leiva, Alicia; Andrés, Pilar; Servera, Mateu; Verbruggen, Frederick; Parmentier, Fabrice B R

    2016-09-01

    Sounds deviating from an otherwise repeated or structured sequence capture attention and affect performance in an ongoing visual task negatively, testament to the balance between selective attention and change detection. Although deviance distraction has been the object of much research, its modulation across the life span has been more scarcely addressed. Recent findings suggest possible connections with working memory and response inhibition. In this study we measured the performance of children and young and older adults in a cross-modal oddball task (deviance distraction), a working memory task (working memory capacity), and a response inhibition task (ability to voluntarily inhibit an already planned action) with the aim to establish the contribution of the latter 2 to the first. Older adults exhibited significantly more deviance distraction than children and young adults (who did not differ from each other). Working memory capacity mediated deviance distraction in children and older adults (though in opposite directions) but not in young adults. Response inhibition capacities did not mediate deviance distraction in any of the age groups. Altogether the results suggest that although the increase in deviance distraction observed in old age may partly reflect the relative impairment of working memory mechanisms, there is no straightforward and stable relation between working memory capacity and deviance distraction across the life span. Furthermore, our results indicate that deviance distraction is unlikely to reflect the temporary inhibition of responses. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

  19. Using Real Colors to Transform Organizational Culture

    ERIC Educational Resources Information Center

    Roback, Paul

    2017-01-01

    Extension educators are frequently tasked with strengthening organizations they collaborate with or provide education to. When a county government in Wisconsin experienced significant personnel changes in a span of less than 18 months, department heads contacted Extension to request professional development and team-building education for their…

  20. Study Identifies Best Pavement Practices in Wet-Freeze Climates : Research Spotlight

    DOT National Transportation Integrated Search

    2017-01-01

    In 2015, Michigan Public Act 175 established the Roads Innovation Task Force. It directed MDOT to determine how the agency could improve the effective life span of state highways, with a goal of 50- to 75-year pavement longevity and reduced costs. MD...

  1. Classification of functional near-infrared spectroscopy signals corresponding to the right- and left-wrist motor imagery for development of a brain-computer interface.

    PubMed

    Naseer, Noman; Hong, Keum-Shik

    2013-10-11

    This paper presents a study on functional near-infrared spectroscopy (fNIRS) indicating that the hemodynamic responses of the right- and left-wrist motor imageries have distinct patterns that can be classified using a linear classifier for the purpose of developing a brain-computer interface (BCI). Ten healthy participants were instructed to imagine kinesthetically the right- or left-wrist flexion indicated on a computer screen. Signals from the right and left primary motor cortices were acquired simultaneously using a multi-channel continuous-wave fNIRS system. Using two distinct features (the mean and the slope of change in the oxygenated hemoglobin concentration), the linear discriminant analysis classifier was used to classify the right- and left-wrist motor imageries resulting in average classification accuracies of 73.35% and 83.0%, respectively, during the 10s task period. Moreover, when the analysis time was confined to the 2-7s span within the overall 10s task period, the average classification accuracies were improved to 77.56% and 87.28%, respectively. These results demonstrate the feasibility of an fNIRS-based BCI and the enhanced performance of the classifier by removing the initial 2s span and/or the time span after the peak value. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  2. Job task characteristics of Australian emergency services volunteers during search and rescue operations.

    PubMed

    Silk, Aaron; Lenton, Gavin; Savage, Robbie; Aisbett, Brad

    2018-02-01

    Search and rescue operations are necessary in locating, assisting and recovering individuals lost or in distress. In Australia, land-based search and rescue roles require a range of physically demanding tasks undertaken in dynamic and challenging environments. The aim of the current research was to identify and characterise the physically demanding tasks inherent to search and rescue operation personnel within Australia. These aims were met through a subjective job task analysis approach. In total, 11 criterion tasks were identified by personnel. These tasks were the most physically demanding, frequently occurring and operationally important tasks to these specialist roles. Muscular strength was the dominant fitness component for 7 of the 11 tasks. In addition to the discrete criterion tasks, an operational scenario was established. With the tasks and operational scenario identified, objective task analysis procedures can be undertaken so that practitioners can implement evidence-based strategies, such as physical selection procedures and task-based physical training programs, commensurate with the physical demands of search and rescue job roles. Practitioner Summary: The identification of physically demanding tasks amongst specialist emergency service roles predicates health and safety strategies which can be incorporated into organisations. Knowledge of physical task parameters allows employers to mitigate injury risk through the implementation of strategies modelled on the precise physical demands of the role.

  3. 12. Interior detail of bridge operator's house showing generator and ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    12. Interior detail of bridge operator's house showing generator and bridge operator, Mr. Gene Amonette, facing west. - Palm Valley Bridge, County Road 210 spanning Intracoastal Waterway, Ponte Vedra Beach, St. Johns County, FL

  4. What is working memory capacity, and how can we measure it?

    PubMed Central

    Wilhelm, Oliver; Hildebrandt, Andrea; Oberauer, Klaus

    2013-01-01

    A latent variable study examined whether different classes of working-memory tasks measure the same general construct of working-memory capacity (WMC). Data from 270 subjects were used to examine the relationship between Binding, Updating, Recall-N-back, and Complex Span tasks, and the relations of WMC with secondary memory measures, indicators of cognitive control from two response-conflict paradigms (Simon task and Eriksen flanker task), and fluid intelligence. Confirmatory factor analyses support the concept of a general WMC factor. Results from structural-equation modeling show negligible relations of WMC with response-conflict resolution, and very strong relations of WMC with secondary memory and fluid intelligence. The findings support the hypothesis that individual differences in WMC reflect the ability to build, maintain and update arbitrary bindings. PMID:23898309

  5. Task-dependent signal variations in EEG error-related potentials for brain-computer interfaces.

    PubMed

    Iturrate, I; Montesano, L; Minguez, J

    2013-04-01

    A major difficulty of brain-computer interface (BCI) technology is dealing with the noise of EEG and its signal variations. Previous works studied time-dependent non-stationarities for BCIs in which the user's mental task was independent of the device operation (e.g., the mental task was motor imagery and the operational task was a speller). However, there are some BCIs, such as those based on error-related potentials, where the mental and operational tasks are dependent (e.g., the mental task is to assess the device action and the operational task is the device action itself). The dependence between the mental task and the device operation could introduce a new source of signal variations when the operational task changes, which has not been studied yet. The aim of this study is to analyse task-dependent signal variations and their effect on EEG error-related potentials. The work analyses the EEG variations on the three design steps of BCIs: an electrophysiology study to characterize the existence of these variations, a feature distribution analysis and a single-trial classification analysis to measure the impact on the final BCI performance. The results demonstrate that a change in the operational task produces variations in the potentials, even when EEG activity exclusively originated in brain areas related to error processing is considered. Consequently, the extracted features from the signals vary, and a classifier trained with one operational task presents a significant loss of performance for other tasks, requiring calibration or adaptation for each new task. In addition, a new calibration for each of the studied tasks rapidly outperforms adaptive techniques designed in the literature to mitigate the EEG time-dependent non-stationarities.

  6. Task-dependent signal variations in EEG error-related potentials for brain-computer interfaces

    NASA Astrophysics Data System (ADS)

    Iturrate, I.; Montesano, L.; Minguez, J.

    2013-04-01

    Objective. A major difficulty of brain-computer interface (BCI) technology is dealing with the noise of EEG and its signal variations. Previous works studied time-dependent non-stationarities for BCIs in which the user’s mental task was independent of the device operation (e.g., the mental task was motor imagery and the operational task was a speller). However, there are some BCIs, such as those based on error-related potentials, where the mental and operational tasks are dependent (e.g., the mental task is to assess the device action and the operational task is the device action itself). The dependence between the mental task and the device operation could introduce a new source of signal variations when the operational task changes, which has not been studied yet. The aim of this study is to analyse task-dependent signal variations and their effect on EEG error-related potentials.Approach. The work analyses the EEG variations on the three design steps of BCIs: an electrophysiology study to characterize the existence of these variations, a feature distribution analysis and a single-trial classification analysis to measure the impact on the final BCI performance.Results and significance. The results demonstrate that a change in the operational task produces variations in the potentials, even when EEG activity exclusively originated in brain areas related to error processing is considered. Consequently, the extracted features from the signals vary, and a classifier trained with one operational task presents a significant loss of performance for other tasks, requiring calibration or adaptation for each new task. In addition, a new calibration for each of the studied tasks rapidly outperforms adaptive techniques designed in the literature to mitigate the EEG time-dependent non-stationarities.

  7. Tuning the heat transfer medium and operating conditions in magnetic refrigeration

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ghahremani, Mohammadreza, E-mail: mghahrem@shepherd.edu; Dept. of Electrical and Computer Engineering, The George Washington University, Washington DC 20052; Aslani, Amir

    A new experimental test bed has been designed, built, and tested to evaluate the effect of the system’s parameters on a reciprocating Active Magnetic Regenerator (AMR) near room temperature. Bulk gadolinium was used as the refrigerant, silicon oil as the heat transfer medium, and a magnetic field of 1.3 T was cycled. This study focuses on the methodology of single stage AMR operation conditions to get a high temperature span near room temperature. Herein, the main objective is not to report the absolute maximum attainable temperature span seen in an AMR system, but rather to find the system’s optimal operatingmore » conditions to reach that maximum span. The results of this research show that there is a optimal operating frequency, heat transfer fluid flow rate, flow duration, and displaced volume ratio in any AMR system. By optimizing these parameters in our AMR apparatus the temperature span between the hot and cold ends increased by 24%. The optimized values are system dependent and need to be determined and measured for any AMR system by following the procedures that are introduced in this research. It is expected that such optimization will permit the design of a more efficient magnetic refrigeration system.« less

  8. Performance tasks for operator-skills research.

    DOT National Transportation Integrated Search

    1966-06-01

    The selection, development, and operation of several tasks for use in skilled-operator-performance research are described. The tasks are intended, collectively, to sample a broad spectrum of abilities required by complex operator systems; individuall...

  9. Expanded pharmacy technician roles: Accepting verbal prescriptions and communicating prescription transfers.

    PubMed

    Frost, Timothy P; Adams, Alex J

    2017-11-01

    As the role of the clinical pharmacist continues to develop and advance, it is critical to ensure pharmacists can operate in a practice environment and workflow that supports the full deployment of their clinical skills. When pharmacy technician roles are optimized, patient safety can be enhanced and pharmacists may dedicate more time to advanced clinical services. Currently, 17 states allow technicians to accept verbal prescriptions called in by a prescriber or prescriber's agent, or transfer a prescription order from one pharmacy to another. States that allow these activities generally put few legal limitations on them, and instead defer to the professional judgment of the supervising pharmacist whether to delegate these tasks or not. These activities were more likely to be seen in states that require technicians to be registered and certified, and in states that have accountability mechanisms (e.g., discipline authority) in place for technicians. There is little evidence to suggest these tasks cannot be performed safely and accurately by appropriately trained technicians, and the track record of success with these tasks spans four decades in some states. Pharmacists can adopt strong practice policies and procedures to mitigate the risk of harm from verbal orders, such as instituting read-back/spell-back techniques, or requiring the indication for each phoned-in medication, among other strategies. Pharmacists may also exercise discretion in deciding to whom to delegate these tasks. As the legal environment becomes more permissive, we foresee investment in more robust education and training of technicians to cover these activities. Thus, with the adoption of robust practice policies and procedures, delegation of verbal orders and prescription transfers can be safe and effective, remove undue stress on pharmacists, and potentially free up pharmacist time for higher-order clinical care. Copyright © 2016 Elsevier Inc. All rights reserved.

  10. 77 FR 12514 - Drawbridge Operation Regulation; Hood Canal, WA

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-01

    ... of 45 minutes during and after openings of the draw span. The stopped road traffic on this two-lane... hundred feet unless the maximum opening of 600 feet is requested. The current regulations remain in effect... three navigational openings for vessel passage, the movable floating span, subject to this proposed...

  11. 26. VIEW FROM EAST IN BRIDGE TENDER'S HOUSE, LEVERS FOR ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    26. VIEW FROM EAST IN BRIDGE TENDER'S HOUSE, LEVERS FOR GASOLINE ENGINE OPERATION FOR BRIDGE AND THEIR CONNECTIONS TO CONTROL RODS ON DOWNSTREAM SIDE OF SWING-SPAN; new bridge located in background - Tipers Bridge, Spanning Great Wicomico River at State Route 200, Kilmarnock, Lancaster County, VA

  12. 77 FR 57020 - Drawbridge Operation Regulation; Carlin Bayou, LA

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-09-17

    ... lift bridge across Carlin Bayou in Delcambre, Iberia Parish, Louisiana. The bridge currently remains in... meeting was requested, and none was held. B. Basis and Purpose The LDRR vertical lift span bridge crosses... when the lift span is in the closed-to-navigation position, mariners may call the LDRR Signal...

  13. Effects of dual task difficulty in motor and cognitive performance: Differences between adults and adolescents.

    PubMed

    Bustillo-Casero, Pilar; Villarrasa-Sapiña, Israel; García-Massó, Xavier

    2017-10-01

    In the present study our aim was to compare dual-task performance in thirteen adolescents and fifteen young adults while concurrently performing a cognitive and a motor task. The postural control variables were obtained under three different conditions: i) bipedal stance, ii) tandem stance and iii) unipedal stance. The cognitive task consisted of a backward digit span test in which the participants were asked to memorize a sequence of numbers and then repeat the number in reverse order at three different difficulty levels (i.e. with 3, 4 and 5 digits). The difficulty of the cognitive task was seen to have different effects on adolescents and young adults. Adolescents seem to prioritize postural control during high difficulty postural conditions while a cross-domain competition model appeared in easy postural conditions. Copyright © 2017 Elsevier B.V. All rights reserved.

  14. Effects of Cogmed working memory training on cognitive performance.

    PubMed

    Etherton, Joseph L; Oberle, Crystal D; Rhoton, Jayson; Ney, Ashley

    2018-04-16

    Research on the cognitive benefits of working memory training programs has produced inconsistent results. Such research has frequently used laboratory-specific training tasks, or dual-task n-back training. The current study used the commercial Cogmed Working Memory (WM) Training program, involving several different training tasks involving visual and auditory input. Healthy college undergraduates were assigned to either the full Cogmed training program of 25, 40-min training sessions; an abbreviated Cogmed program of 25, 20-min training sessions; or a no-contact control group. Pretest and posttest measures included multiple measures of attention, working memory, fluid intelligence, and executive functions. Although improvement was observed for the full training group for a digit span task, no training-related improvement was observed for any of the other measures. Results of the study suggest that WM training does not improve performance on unrelated tasks or enhance other cognitive abilities.

  15. The Influence of Positive Mood on Different Aspects of Cognitive Control

    PubMed Central

    Martin, Elizabeth A.; Kerns, John G.

    2010-01-01

    Some evidence suggests that positive mood influences cognitive control. The current research investigated whether positive mood has differential effects on two aspects of cognitive control, working memory and prepotent response inhibition. In Study 1, following either a positive or neutral mood induction, participants completed the Running Memory Span (RMS), a measure primarily of working memory storage capacity, and the Stroop task, a measure of prepotent response inhibition. Results were that the positive mood group performed worse on the RMS task but not on the Stroop task. In Study 2, participants completed the RMS and another measure of prepotent response inhibition, the Flanker task. Results were that when in a positive mood state participants performed worse on the RMS but not on the Flanker task. Overall, this research suggests that positive mood has differential effects on cognitive control, impairing working memory but having no effect on prepotent response inhibition. PMID:21399720

  16. The development of memory efficiency and value-directed remembering across the life span: a cross-sectional study of memory and selectivity.

    PubMed

    Castel, Alan D; Humphreys, Kathryn L; Lee, Steve S; Galván, Adriana; Balota, David A; McCabe, David P

    2011-11-01

    Although attentional control and memory change considerably across the life span, no research has examined how the ability to strategically remember important information (i.e., value-directed remembering) changes from childhood to old age. The present study examined this in different age groups across the life span (N = 320, 5-96 years old). A selectivity task was used in which participants were asked to study and recall items worth different point values in order to maximize their point score. This procedure allowed for measures of memory quantity/capacity (number of words recalled) and memory efficiency/selectivity (the recall of high-value items relative to low-value items). Age-related differences were found for memory capacity, as young adults recalled more words than the other groups. However, in terms of selectivity, younger and older adults were more selective than adolescents and children. The dissociation between these measures across the life span illustrates important age-related differences in terms of memory capacity and the ability to selectively remember high-value information.

  17. Modulation of Frontoparietal Neurovascular Dynamics in Working Memory

    PubMed Central

    Ardestani, Allen; Shen, Wei; Darvas, Felix; Toga, Arthur W.; Fuster, Joaquin M.

    2016-01-01

    Our perception of the world is represented in widespread, overlapping, and interactive neuronal networks of the cerebral cortex. A majority of physiological studies on the subject have focused on oscillatory synchrony as the binding mechanism for representation and transmission of neural information. Little is known, however, about the stability of that synchrony during prolonged cognitive operations that span more than just a few seconds. The present research, in primates, investigated the dynamic patterns of oscillatory synchrony by two complementary recording methods, surface field potentials (SFPs) and near-infrared spectroscopy (NIRS). The signals were first recorded during the resting state to examine intrinsic functional connectivity. The temporal modulation of coactivation was then examined on both signals during performance of working memory ( WM) tasks with long delays (memory retention epochs). In both signals, the peristimulus period exhibited characteristic features in frontal and parietal regions. Examination of SFP signals over delays lasting tens of seconds, however, revealed alternations of synchronization and desynchronization. These alternations occurred within the same frequency bands observed in the peristimulus epoch, without a specific correspondence between any definite cognitive process (e.g., WM) and synchrony within a given frequency band. What emerged instead was a correlation between the degree of SFP signal fragmentation (in time, frequency, and brain space) and the complexity and efficiency of the task being performed. In other words, the incidence and extent of SFP transitions between synchronization and desynchronization—rather than the absolute degree of synchrony—augmented in correct task performance compared with incorrect performance or in a control task without WM demand. An opposite relationship was found in NIRS: increasing task complexity induced more uniform, rather than fragmented, NIRS coactivations. These findings indicate that the particular features of neural oscillations cannot be linearly mapped to cognitive functions. Rather, information and the cognitive operations performed on it are primarily reflected in their modulations over time. The increased complexity and fragmentation of electrical frequencies in WM may reflect the activation of hierarchically diverse cognits (cognitive networks) in that condition. Conversely, the homogeneity in coherence of NIRS responses may reflect the cumulative vascular reactions that accompany that neuroelectrical proliferation of frequencies and the longer time constant of the NIRS signal. These findings are directly relevant to the mechanisms mediating cognitive processes and to physiologically based interpretations of functional brain imaging. PMID:26679214

  18. Memory Span and General Intelligence: A Latent-Variable Approach

    ERIC Educational Resources Information Center

    Colom, Roberto; Abad, Francisco J.; Rebollo, Irene; Chun Shih, Pei

    2005-01-01

    There are several studies showing that working memory and intelligence are strongly related. However, working memory tasks require simultaneous processing and storage, so the causes of their relationship with intelligence are currently a matter of discussion. The present study examined the simultaneous relationships among short-term memory (STM),…

  19. Sensory and Cognitive Determinants of Reading Speed

    ERIC Educational Resources Information Center

    Jackson, Mark D.; McClelland, James L.

    1975-01-01

    Fast and average readers were tested on four tasks. Fast readers appear to pick up more information per fixation on structured textual material, and had a greater span of apprehension for unrelated elements. Results disagree with the view that reading speed depends solely on ability to infer missing information. (CHK)

  20. The Relationships between Cognitive Ability and Dynamic Decision Making

    ERIC Educational Resources Information Center

    Gonzalez, C.; Thomas, R.P.; Vanyukov, P.

    2005-01-01

    This study investigated the relationships between cognitive ability (as assessed by the Raven Progressive Matrices Test [RPM] and the Visual-Span Test [VSPAN]) and individuals' performance in three dynamic decision making (DDM) tasks (i.e., regular Water Purification Plant [WPP], Team WPP, and Firechief). Participants interacted repeatedly with…

  1. Fatigue, Sleep Loss, and Confidence in Judgment

    ERIC Educational Resources Information Center

    Baranski, Joseph V.

    2007-01-01

    Sixty-four adults participated in a study examining the accuracy of metacognitive judgments during 28 hr of sleep deprivation (SD) and continuous cognitive work. Three tasks were studied (perceptual comparison, general knowledge, and mental addition), collectively spanning a range of cognitive abilities and levels of susceptibility to SD.…

  2. Short-Term Memory Coding in Children with Intellectual Disabilities

    ERIC Educational Resources Information Center

    Henry, Lucy

    2008-01-01

    To examine visual and verbal coding strategies, I asked children with intellectual disabilities and peers matched for MA and CA to perform picture memory span tasks with phonologically similar, visually similar, long, or nonsimilar named items. The CA group showed effects consistent with advanced verbal memory coding (phonological similarity and…

  3. Serial Recall and Nonword Repetition in Reading Disabled Children.

    ERIC Educational Resources Information Center

    Roodenrys, Steven; Stokes, Julie

    2001-01-01

    Examines the performance on verbal short-term memory tasks of specifically reading disabled children relative to reading-age matched and chronological-age matched control groups. Examines memory span for words, highly wordlike nonwords and less wordlike nonwords, speech rates for these items, and nonword repetition. Suggests that there is a…

  4. Consequences of Stress for Public School Superintendents

    ERIC Educational Resources Information Center

    Carroll, Kathy J.

    2010-01-01

    Scope and Method of Study: This study is a quantitative study of Oklahoma Public School Superintendents. The data was collected by surveys using an online format. Data was analyzed to determine correlation and predictive values of the four specific stress factors: conflict mediating stress, boundary spanning stress, task based stress and role…

  5. THE YOUNG ADULT--A CONCEPTUAL FRAMEWORK. SUMMARY.

    ERIC Educational Resources Information Center

    CHICKERING, ARTHUR W.

    THE DEVELOPMENTAL STAGE SPANNING THE YEARS FROM 18 TO 25 MUST BE STUDIED SEPARATELY FROM OTHER DEVELOPMENTAL STAGES. THE DEVELOPMENTAL TASKS OF THIS PERIOD ARE RELATED TO, BUT SUBSTANTIALLY DIFFERENT FROM, THOSE OF BOTH ADOLESCENCE AND ADULTHOOD. THE SEVEN MAJOR DEVELOPMENTAL VECTORS FOR THE YOUNG ADULT INCLUDE DEVELOPMENT OF COMPETENCE,…

  6. Measurement of Assertive Behavior: Construct and Predictive Validity of Self-Report, Role-Playing, and In-Vivo Measures.

    ERIC Educational Resources Information Center

    Burkhart, Barry R.

    1979-01-01

    Seventy-five subjects, who spanned the range of assertiveness, completed two self-report measures of assertiveness, eight role-playing situations involving positive and negative assertiveness, and a telephone in-vivo task. Correlations between the three measurement methods were examined. (Author/SJL)

  7. Life Span Changes in Visual Enumeration: The Number Discrimination Task.

    ERIC Educational Resources Information Center

    Trick, Lana M.; And Others

    1996-01-01

    Ninety-eight participants from 5 age groups with mean ages of 6, 8, 10, 22, and 72 years were tested in a series of speeded number discriminations. Found that response time slope as a function of number size decreased with age for numbers in the 1-4 range. (MDM)

  8. Processing Determinants of Reading Speed.

    ERIC Educational Resources Information Center

    Jackson, Mark D.; McClelland, James L.

    1979-01-01

    Two groups of undergraduates differing in reading ability were tested on a number of reaction-time tasks designed to determine the speed of encoding visual information at several different levels, tests of sensory functions, verbal and quantitative reasoning ability, short-term auditory memory span, and ability to comprehend spoken text.…

  9. Sensation seeking and visual selective attention in adults with HIV/AIDS.

    PubMed

    Hardy, David J; Castellon, Steven A; Hinkin, Charles H; Levine, Andrew J; Lam, Mona N

    2008-11-01

    The association between sensation seeking and visual selective attention was examined in 31 adults with the Human Immunodeficiency Virus (HIV). Sensation seeking was measured with Zuckerman's Sensation Seeking Scale Form V (SSS-V). Selective attention was assessed with a perceptual span task, where a target letter-character must be identified in a quickly presented array of nontarget letter-characters. As predicted, sensation seeking was strongly associated (R(2) = .229) with perceptual span performance in the array size 12 condition, where selective attention demands were greatest, but not in the easier conditions. The Disinhibition, Boredom Susceptibility, and Experience Seeking subscales of the SSS-V were associated with span performance. It is argued that personality factors such as sensation seeking may play a significant role in selective attention and related cognitive abilities in HIV positive adults. Furthermore, sensation seeking differences might explain certain inconsistencies in the HIV neuropsychology literature.

  10. Interactions of age and cognitive functions in predicting decision making under risky conditions over the life span.

    PubMed

    Brand, Matthias; Schiebener, Johannes

    2013-01-01

    Little is known about how normal healthy aging affects decision-making competence. In this study 538 participants (age 18-80 years) performed the Game of Dice Task (GDT). Subsamples also performed the Iowa Gambling Task as well as tasks measuring logical thinking and executive functions. In a moderated regression analysis, the significant interaction between age and executive components indicates that older participants with good executive functioning perform well on the GDT, while older participants with reduced executive functions make more risky choices. The same pattern emerges for the interaction of age and logical thinking. Results demonstrate that age and cognitive functions act in concert in predicting the decision-making performance.

  11. The suppression effect in visuospatial and verbal working memory span tasks in patients with Alzheimer's disease: a 2-year follow-up study.

    PubMed

    Elosúa, M Rosa; Peinado, Matías; Contreras, María José; Reales, J Manuel; Montoro, Pedro R

    2016-10-01

    This study adapted a new task to assess visuospatial and verbal working memory impairments in patients with Alzheimer Disease (AD), including an executive strategy of information suppression. The aim was to examine the visuospatial and verbal difficulties, and additionally to explore the average sex differences, during a 2-year follow-up study. The results indicated that patients with AD showed a significantly lower performance, compared with healthy elderly controls, especially with the suppression of information required in this new task. However, suppression did not lead to a significantly greater decline in the performance of patients when compared with the control group.

  12. A Decision Aid for Addressing Supervisor Span of Control Problems

    DTIC Science & Technology

    1984-01-01

    34 SNALRT 2880 2880 2880 9 20 30 <- SAMMO 2880 1440 720 3 21 6 SMAINT 1440 1440 1440 5 22 40 "" SMED 1440 1440 1440 5 23 20 , TASK LIBRARY FOR THREE...5 22 60 SMED 1440 1440 1440 5 23 20 TASK LIBRARY FOR FOUR LAUNCHER PLATOON MOVE 1440 480 240 7 1 8 2 1 3 50 4 3 -------------_ 5 57 m 6 1 •7 1 8 50 9...2880 2880 9 20 30 SAMMO 2880 720 360 3 21 6 SMAINT 1440 1440 1440 5 22 80 SMED 1440 1440 1440 5 23 20 TASK LIBRARY FOR FIVE LAUNCHER PLATOON MOVE 1440

  13. Episodic, semantic and procedural memory in a case of amnesia at an early age.

    PubMed

    Ostergaard, A L

    1987-01-01

    The patient C.C. developed an amnesic syndrome at the age of 10 yr. Like adult amnesics, C.C. demonstrated impaired episodic memory for both verbal and visual materials although immediate memory span was spared. However, striking deficits were also observed on a wide variety of semantic memory tasks, including reading vocabulary and verbal fluency tests, semantic classification and lexical decision tasks and tests of verbal intelligence. On the other hand, C.C. showed normal learning and retention of two procedural tasks. It was argued that this evidence is inconsistent with the view that the amnesic syndrome represents a selective defect of episodic memory that leaves semantic memory relatively unaffected.

  14. Evidence for deficits in the temporal attention span of poor readers.

    PubMed

    Visser, Troy A W

    2014-01-01

    While poor reading is often associated with phonological deficits, many studies suggest that visual processing might also be impaired. In particular, recent research has indicated that poor readers show impaired spatial visual attention spans in partial and whole report tasks. Given the similarities between competition-based accounts for reduced visual attention span and similar explanations for impairments in sequential object processing, the present work examined whether poor readers show deficits in their "temporal attention span"--that is, their ability to rapidly and accurately process sequences of consecutive target items. Poor and normal readers monitored a sequential stream of visual items for two (TT condition) or three (TTT condition) consecutive target digits. Target identification was examined using both unconditional and conditional measures of accuracy in order to gauge the overall likelihood of identifying a target and the likelihood of identifying a target given successful identification of previous items. Compared to normal readers, poor readers showed small but consistent deficits in identification across targets whether unconditional or conditional accuracy was used. Additionally, in the TTT condition, final-target conditional accuracy was poorer than unconditional accuracy, particularly for poor readers, suggesting a substantial cost arising from processing the previous two targets that was not present in normal readers. Mirroring the differences found between poor and normal readers in spatial visual attention span, the present findings suggest two principal differences between the temporal attention spans of poor and normal readers. First, the consistent pattern of reduced performance across targets suggests increased competition amongst items within the same span for poor readers. Second, the steeper decline in final target performance amongst poor readers in the TTT condition suggests a reduction in the extent of their temporal attention span.

  15. Effects of task demands on the early neural processing of fearful and happy facial expressions

    PubMed Central

    Itier, Roxane J.; Neath-Tavares, Karly N.

    2017-01-01

    Task demands shape how we process environmental stimuli but their impact on the early neural processing of facial expressions remains unclear. In a within-subject design, ERPs were recorded to the same fearful, happy and neutral facial expressions presented during a gender discrimination, an explicit emotion discrimination and an oddball detection tasks, the most studied tasks in the field. Using an eye tracker, fixation on the face nose was enforced using a gaze-contingent presentation. Task demands modulated amplitudes from 200–350ms at occipito-temporal sites spanning the EPN component. Amplitudes were more negative for fearful than neutral expressions starting on N170 from 150–350ms, with a temporo-occipital distribution, whereas no clear effect of happy expressions was seen. Task and emotion effects never interacted in any time window or for the ERP components analyzed (P1, N170, EPN). Thus, whether emotion is explicitly discriminated or irrelevant for the task at hand, neural correlates of fearful and happy facial expressions seem immune to these task demands during the first 350ms of visual processing. PMID:28315309

  16. Aging and consumer decision making

    PubMed Central

    Carpenter, Stephanie M.; Yoon, Carolyn

    2013-01-01

    Research on consumer decision making and aging is especially important for fostering a better understanding of ways to maintain consumer satisfaction and high decision quality across the life span. We provide a review of extant research on the effects of normal aging on cognition and decision processes and how these age-related processes are influenced by task environment, meaningfulness of the task, and consumer expertise. We consider how research centered on these topics generates insights about changes in consumption decisions that occur with aging and identify a number of gaps and directions for future research. PMID:22360794

  17. Accessibility limits recall from visual working memory.

    PubMed

    Rajsic, Jason; Swan, Garrett; Wilson, Daryl E; Pratt, Jay

    2017-09-01

    In this article, we demonstrate limitations of accessibility of information in visual working memory (VWM). Recently, cued-recall has been used to estimate the fidelity of information in VWM, where the feature of a cued object is reproduced from memory (Bays, Catalao, & Husain, 2009; Wilken & Ma, 2004; Zhang & Luck, 2008). Response error in these tasks has been largely studied with respect to failures of encoding and maintenance; however, the retrieval operations used in these tasks remain poorly understood. By varying the number and type of object features provided as a cue in a visual delayed-estimation paradigm, we directly assess the nature of retrieval errors in delayed estimation from VWM. Our results demonstrate that providing additional object features in a single cue reliably improves recall, largely by reducing swap, or misbinding, responses. In addition, performance simulations using the binding pool model (Swan & Wyble, 2014) were able to mimic this pattern of performance across a large span of parameter combinations, demonstrating that the binding pool provides a possible mechanism underlying this pattern of results that is not merely a symptom of one particular parametrization. We conclude that accessing visual working memory is a noisy process, and can lead to errors over and above those of encoding and maintenance limitations. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  18. Modulation of the attentional span by foveal and parafoveal task load: An ERP study using attentional probes.

    PubMed

    Kornrumpf, Benthe; Sommer, Werner

    2015-09-01

    Due to capacity limitation, visual attention must be focused to a limited region of the visual field. Nevertheless, it is assumed that the size of that region may vary with task demands. We aimed to obtain direct evidence for the modulation of visuospatial attention as a function of foveal and parafoveal task load. Participants were required to fixate the center word of word triplets. In separate task blocks, either just the fixated word or both the fixated and the parafoveal word to the right should be semantically classified. The spatiotemporal distribution of attention was assessed with task-irrelevant probes flashed briefly at center or parafoveal positions, during or in between word presentation trials. The N1 component of the ERP elicited by intertrial probes at possible target positions increased with task demands within a block. These results suggest the recruitment of additional attentional resources rather than a redistribution of a fixed resource pool, which persists across trials. © 2015 Society for Psychophysiological Research.

  19. Mastering social and organization goals: strategy use by two children with Asperger syndrome during cognitive orientation to daily occupational performance.

    PubMed

    Rodger, Sylvia; Vishram, Alysha

    2010-11-01

    Preliminary data supports the effectiveness of Cognitive Orientation to (daily) Occupational Performance (CO-OP) for children with Asperger syndrome (AS). Children with AS often experience social and organizational difficulties spanning daily occupations. This case study explored the pattern of Global Strategies and Domain-Specific Strategies (DSS) use, the type of guidance, and dimensions of time on task used by two children with AS (aged 10 and 12 years) in addressing social and organizational goals during the CO-OP intervention. Coding of the videotaped CO-OP sessions suggested that both children (a) utilized all the Global strategies, particularly "understanding the context” and "plan"; (b) used six common DSS, namely transitional supports, affective supports, attending, task-specification, task modification, and supplementing task knowledge, with task-specification being most prominent; (c) required minimal guidance while "doing"; and (d) engaged in considerable time "talking about the task.” The results provide initial insights into strategies that may enable children with AS to achieve social and organizational goals.

  20. Executive functioning as a predictor of children's mathematics ability: inhibition, switching, and working memory.

    PubMed

    Bull, R; Scerif, G

    2001-01-01

    Children's mathematical skills were considered in relation to executive functions. Using multiple measures--including the Wisconsin Card Sorting Task (WCST), dual-task performance, Stroop task, and counting span-it was found that mathematical ability was significantly correlated with all measures of executive functioning, with the exception of dual-task performance. Furthermore, regression analyses revealed that each executive function measure predicted unique variance in mathematics ability. These results are discussed in terms of a central executive with diverse functions (Shallice & Burgess, 1996) and with recent evidence from Miyake, et al. (2000) showing the unity and diversity among executive functions. It is proposed that the particular difficulties for children of lower mathematical ability are lack of inhibition and poor working memory, which result in problems with switching and evaluation of new strategies for dealing with a particular task. The practical and theoretical implications of these results are discussed, along with suggestions for task changes and longitudinal studies that would clarify theoretical and developmental issues related to executive functioning.

  1. 40 CFR 60.13 - Monitoring requirements.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... operators of a CEMS installed in accordance with the provisions of this part, must check the zero (or low...) calibration drifts at least once daily in accordance with a written procedure. The zero and span must, as a minimum, be adjusted whenever either the 24-hour zero drift or the 24-hour span drift exceeds two times...

  2. 40 CFR 60.13 - Monitoring requirements.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... operators of a CEMS installed in accordance with the provisions of this part, must check the zero (or low...) calibration drifts at least once daily in accordance with a written procedure. The zero and span must, as a minimum, be adjusted whenever either the 24-hour zero drift or the 24-hour span drift exceeds two times...

  3. 40 CFR 60.13 - Monitoring requirements.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... operators of a CEMS installed in accordance with the provisions of this part, must check the zero (or low...) calibration drifts at least once daily in accordance with a written procedure. The zero and span must, as a minimum, be adjusted whenever either the 24-hour zero drift or the 24-hour span drift exceeds two times...

  4. 77 FR 29927 - Drawbridge Operation Regulation; Carlin Bayou, LA

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-05-21

    ... Louisiana and Delta Railroad (LDRR) vertical lift bridge across Carlin Bayou in Delcambre, Iberia Parish... comply with the requirements of 33 CFR part 117.41. C. Basis and Purpose The LDRR vertical lift span... lift span is in the closed-to-navigation position, mariners may call the LDRR Signal Supervisor at 337...

  5. 78 FR 36654 - Drawbridge Operation Regulation; Neches River, Beaumont, TX

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-06-19

    ... that governs the Kansas City Southern vertical lift span bridge across the Neches River, mile 19.5, at Beaumont, Texas. The deviation is necessary to replace the north vertical lift joints on the bridge. This... of the vertical lift span bridge across the Neches River at mile 19.5 in Beaumont, Texas. The...

  6. 78 FR 29020 - Drawbridge Operation Regulation; Neches River, Beaumont, TX

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-05-17

    ... that governs the Kansas City Southern vertical lift span bridge across the Neches River, mile 19.5, at Beaumont, Texas. The deviation is necessary to replace the north vertical lift joints on the bridge. This... of the vertical lift span bridge across the Neches River at mile 19.5 in Beaumont, Texas. The...

  7. 40 CFR 60.13 - Monitoring requirements.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... operators of a CEMS installed in accordance with the provisions of this part, must check the zero (or low...) calibration drifts at least once daily in accordance with a written procedure. The zero and span must, as a minimum, be adjusted whenever either the 24-hour zero drift or the 24-hour span drift exceeds two times...

  8. Brain and effort: brain activation and effort-related working memory in healthy participants and patients with working memory deficits.

    PubMed

    Engström, Maria; Landtblom, Anne-Marie; Karlsson, Thomas

    2013-01-01

    Despite the interest in the neuroimaging of working memory, little is still known about the neurobiology of complex working memory in tasks that require simultaneous manipulation and storage of information. In addition to the central executive network, we assumed that the recently described salience network [involving the anterior insular cortex (AIC) and the anterior cingulate cortex (ACC)] might be of particular importance to working memory tasks that require complex, effortful processing. Healthy participants (n = 26) and participants suffering from working memory problems related to the Kleine-Levin syndrome (KLS) (a specific form of periodic idiopathic hypersomnia; n = 18) participated in the study. Participants were further divided into a high- and low-capacity group, according to performance on a working memory task (listening span). In a functional magnetic resonance imaging (fMRI) study, participants were administered the reading span complex working memory task tapping cognitive effort. The fMRI-derived blood oxygen level dependent (BOLD) signal was modulated by (1) effort in both the central executive and the salience network and (2) capacity in the salience network in that high performers evidenced a weaker BOLD signal than low performers. In the salience network there was a dichotomy between the left and the right hemisphere; the right hemisphere elicited a steeper increase of the BOLD signal as a function of increasing effort. There was also a stronger functional connectivity within the central executive network because of increased task difficulty. The ability to allocate cognitive effort in complex working memory is contingent upon focused resources in the executive and in particular the salience network. Individual capacity during the complex working memory task is related to activity in the salience (but not the executive) network so that high-capacity participants evidence a lower signal and possibly hence a larger dynamic response.

  9. Brain and effort: brain activation and effort-related working memory in healthy participants and patients with working memory deficits

    PubMed Central

    Engström, Maria; Landtblom, Anne-Marie; Karlsson, Thomas

    2013-01-01

    Despite the interest in the neuroimaging of working memory, little is still known about the neurobiology of complex working memory in tasks that require simultaneous manipulation and storage of information. In addition to the central executive network, we assumed that the recently described salience network [involving the anterior insular cortex (AIC) and the anterior cingulate cortex (ACC)] might be of particular importance to working memory tasks that require complex, effortful processing. Method: Healthy participants (n = 26) and participants suffering from working memory problems related to the Kleine–Levin syndrome (KLS) (a specific form of periodic idiopathic hypersomnia; n = 18) participated in the study. Participants were further divided into a high- and low-capacity group, according to performance on a working memory task (listening span). In a functional magnetic resonance imaging (fMRI) study, participants were administered the reading span complex working memory task tapping cognitive effort. Principal findings: The fMRI-derived blood oxygen level dependent (BOLD) signal was modulated by (1) effort in both the central executive and the salience network and (2) capacity in the salience network in that high performers evidenced a weaker BOLD signal than low performers. In the salience network there was a dichotomy between the left and the right hemisphere; the right hemisphere elicited a steeper increase of the BOLD signal as a function of increasing effort. There was also a stronger functional connectivity within the central executive network because of increased task difficulty. Conclusion: The ability to allocate cognitive effort in complex working memory is contingent upon focused resources in the executive and in particular the salience network. Individual capacity during the complex working memory task is related to activity in the salience (but not the executive) network so that high-capacity participants evidence a lower signal and possibly hence a larger dynamic response. PMID:23616756

  10. 75 FR 50707 - Drawbridge Operation Regulation; Curtis Creek, Baltimore, MD

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-17

    ... double-leaf bascule drawbridge, has requested a temporary deviation from the current general operating... half of the draw spans to single-leaf operation. The drawbridge will operate as follows: (1) Closed to..., vessels openings will be provided if at least 48 hours advance notice is given; (2) Single leaf operation...

  11. 11. View of bridge operator's control cabin from Seekonk River ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    11. View of bridge operator's control cabin from Seekonk River looking northwest - India Point Railroad Bridge, Spanning Seekonk River between Providence & East Providence, Providence, Providence County, RI

  12. 33. Three bolts on railing outside control house on north ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    33. Three bolts on railing outside control house on north tower, one bolt on first handrail post of the north span (bridge is in the open position). As the bridge opens or closes the single bolt on the handrail post moves past the three stationary bolts. This system is used by the bridge operator to judge speed and position of the north span as it opens or closes. Based on these bolts movement of the north span is speeded up or slowed down and the brakes applied during the opening and closing process. View facing east. - Henry Ford Bridge, Spanning Cerritos Channel, Los Angeles-Long Beach Harbor, Los Angeles, Los Angeles County, CA

  13. 76 FR 19911 - Drawbridge Operation Regulation; Calcasieu River, Westlake, LA

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-04-11

    ... maintenance and updates to the bridge's operating system. This deviation allows the bridge to remain closed to...'s operating system while minimizing the exposure of personnel to hazards associated with performing... deviation from the operating schedule for the swing span bridge across the Calcasieu River, mile 36.4, at...

  14. 78 FR 18479 - Drawbridge Operation Regulations; Pass Manchac, LA

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-03-27

    ... governing the operation of the Canadian National (CN) Railroad automated bascule span drawbridge across Pass... necessary to upgrade the electrical drive system and replace the seals on the gear drive unit that operates... Operations, telephone 202-366-9826. SUPPLEMENTARY INFORMATION: The CN Railroad has requested a temporary...

  15. Do differences in visuospatial ability between senile dementias of the Alzheimer and Lewy body types reflect differences solely in mnemonic function?

    PubMed

    Sahgal, A; McKeith, I G; Galloway, P H; Tasker, N; Steckler, T

    1995-02-01

    Visuospatial memory was investigated in two groups of patients suffering from senile dementias of the Alzheimer (SDAT) or Lewy body (SDLT) types; a, third, age-matched, healthy control group was also included. The two patient groups were mildly demented and could not be distinguished from each other by traditional tests of cognitive function. A different pattern of performance emerged in the two groups on a computerised test of spatial working memory, which is a self-ordered pointing task requiring the subject to search for hidden tokens. An analysis of the pattern of errors revealed that the SDLT group made more of both possible types of error ("Within Search" and "Between Search") than the SDAT group. Neither patient groups' performance differed from each other when assessed on a computerised Corsi spatial span task. A measure of planning ability was obtained by examining search strategies. Although an index previously developed to measure the subject's use of a particular strategy in the spatial working memory task failed to detect any differences between the three groups, a novel index was calculated which focuses on performance within a search, and this revealed deficits in both demented groups. Since the two patient groups differed from each other in the spatial working memory, but not the Corsi spatial span, task, it is suggested that the differences between the two demented groups are not due to a specific mnemonic impairment, but reflect dysfunctions in non-mnemonic processes mediated by fronto-subcortical circuits, which are more severely damaged in SDLT.

  16. The contribution of general cognitive abilities and number abilities to different aspects of mathematics in children.

    PubMed

    Träff, Ulf

    2013-10-01

    This study examined the relative contributions of general cognitive abilities and number abilities to word problem solving, calculation, and arithmetic fact retrieval in a sample of 134 children aged 10 to 13 years. The following tasks were administered: listening span, visual matrix span, verbal fluency, color naming, Raven's Progressive Matrices, enumeration, number line estimation, and digit comparison. Hierarchical multiple regressions demonstrated that number abilities provided an independent contribution to fact retrieval and word problem solving. General cognitive abilities contributed to problem solving and calculation. All three number tasks accounted for a similar amount of variance in fact retrieval, whereas only the number line estimation task contributed unique variance in word problem solving. Verbal fluency and Raven's matrices accounted for an equal amount of variance in problem solving and calculation. The current findings demonstrate, in accordance with Fuchs and colleagues' developmental model of mathematical learning (Developmental Psychology, 2010, Vol. 46, pp. 1731-1746), that both number abilities and general cognitive abilities underlie 10- to 13-year-olds' proficiency in problem solving, whereas only number abilities underlie arithmetic fact retrieval. Thus, the amount and type of cognitive contribution to arithmetic proficiency varies between the different aspects of arithmetic. Furthermore, how closely linked a specific aspect of arithmetic is to the whole number representation systems is not the only factor determining the amount and type of cognitive contribution in 10- to 13-year-olds. In addition, the mathematical complexity of the task appears to influence the amount and type of cognitive support. Copyright © 2013 Elsevier Inc. All rights reserved.

  17. Intelligence and working memory systems: evidence of neural efficiency in alpha band ERD.

    PubMed

    Grabner, R H; Fink, A; Stipacek, A; Neuper, C; Neubauer, A C

    2004-07-01

    Starting from the well-established finding that brighter individuals display a more efficient brain function when performing cognitive tasks (i.e., neural efficiency), we investigated the relationship between intelligence and cortical activation in the context of working memory (WM) tasks. Fifty-five male (n=28) and female (n=27) participants worked on (1) a classical forward digit span task demanding only short-term memory (STM), (2) an attention-switching task drawing on the central executive (CE) of WM and (3) a WM task involving both STM storage and CE processes. During performance of these three types of tasks, cortical activation was quantified by the extent of Event-Related Desynchronization (ERD) in the alpha band of the human EEG. Correlational analyses revealed associations between the amount of ERD in the upper alpha band and intelligence in several brain regions. In all tasks, the males were more likely to display the negative intelligence-cortical activation relationship. Furthermore, stronger associations between ERD and intelligence were found for fluid rather than crystallized intelligence. Analyses also point to topographical differences in neural efficiency depending on sex, task type and the associated cognitive subsystems engaged during task performance.

  18. Offutt Air Force Base, Looking Glass Airborne Command Post, Operational ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Offutt Air Force Base, Looking Glass Airborne Command Post, Operational & Hangar Access Aprons, Spanning length of northeast half of Project Looking Glass Historic District, Bellevue, Sarpy County, NE

  19. Simple Predictions Fueled by Capacity Limitations: When Are They Successful?

    ERIC Educational Resources Information Center

    Gaissmaier, Wolfgang; Schooler, Lael J.; Rieskamp, Jorg

    2006-01-01

    Counterintuitively, Y. Kareev, I. Lieberman, and M. Lev (1997) found that a lower short-term memory capacity benefits performance on a correlation detection task. They assumed that people with low short-term memory capacity (low spans) perceived the correlations as more extreme because they relied on smaller samples, which are known to exaggerate…

  20. Time-Related Decay or Interference-Based Forgetting in Working Memory?

    ERIC Educational Resources Information Center

    Portrat, Sophie; Barrouillet, Pierre; Camos, Valerie

    2008-01-01

    The time-based resource-sharing model of working memory assumes that memory traces suffer from a time-related decay when attention is occupied by concurrent activities. Using complex continuous span tasks in which temporal parameters are carefully controlled, P. Barrouillet, S. Bernardin, S. Portrat, E. Vergauwe, & V. Camos (2007) recently…

  1. The Rural Elderly: Program Planning Guidelines.

    ERIC Educational Resources Information Center

    Coward, Raymond T.; Kerckhoff, Richard K.

    Designed for the rural practitioner, this manual offers a description of the major developmental tasks faced by individuals during the latter part of the life span and a summary of the major implications that research holds for building community programs for the rural elderly. Section II discusses two major assumptions: (1) because human beings…

  2. Aspects of Working Memory in L2 Learning

    ERIC Educational Resources Information Center

    Juffs, Alan; Harrington, Michael

    2011-01-01

    This article reviews research on working memory (WM) and its use in second language (L2) acquisition research. Recent developments in the model and issues surrounding the operationalization of the construct itself are presented, followed by a discussion of various methods of measuring WM. These methods include word and digit span tasks, reading,…

  3. Identifying Simple Numerical Stimuli: Processing Inefficiencies Exhibited by Arithmetic Learning Disabled Children.

    ERIC Educational Resources Information Center

    Koontz, Kristine L.; Berch, Daniel B.

    1996-01-01

    Children with arithmetic learning disabilities (n=16) and normally achieving controls (n=16) in grades 3-5 were administered a battery of computerized tasks. Memory spans for both letters and digits were found to be smaller among the arithmetic learning disabled children. Implications for teaching are discussed. (Author/CMS)

  4. Investigating the Effects of Veridicality on Age Differences in Verbal Working Memory

    ERIC Educational Resources Information Center

    Shake, Matthew C.; Perschke, Meghan K.

    2013-01-01

    In the typical loaded verbal working memory (WM) span task (e.g., Daneman & Carpenter, 1980), participants judge the veridicality of a series of sentences while simultaneously storing the sentence final word for later recall. Performance declines as the number of sentences is increased; aging exacerbates this decline. The present study examined…

  5. Seven Factors You'd Better Not Forget when Changing Attendance Boundaries.

    ERIC Educational Resources Information Center

    Hyland, Timothy F.

    1989-01-01

    Redrawing school attendance boundaries is one of the most sensitive tasks a school board faces. Factors to consider include the following: (1) life span of the change; (2) effective date; (3) racial balance; (4) resource equity; and (5) program, public, and financial impact. Outlines a process for developing redistricting plans. (MLF)

  6. Children's Conceptions of Work and Play: Exploring an Alternative to the Discounting Principle.

    ERIC Educational Resources Information Center

    Hennessey, Beth A.; Berger, Andrea R.

    Factors such as an expected reward have been shown to severely undermine individuals' intrinsic interest in a given task. This "overjustification effect," or "discounting principle," has been demonstrated across the life span, except in the case of young children, who have been shown to be incapable of engaging in this…

  7. A New Zero-Inflated Negative Binomial Methodology for Latent Category Identification

    ERIC Educational Resources Information Center

    Blanchard, Simon J.; DeSarbo, Wayne S.

    2013-01-01

    We introduce a new statistical procedure for the identification of unobserved categories that vary between individuals and in which objects may span multiple categories. This procedure can be used to analyze data from a proposed sorting task in which individuals may simultaneously assign objects to multiple piles. The results of a synthetic…

  8. Advances in Early Communication and Language Intervention

    ERIC Educational Resources Information Center

    Kaiser, Ann P.; Roberts, Megan Y.

    2011-01-01

    Learning to communicate using speech and language is a primary developmental task for young children. Delays in the acquisition of language are one of the earliest indicators of developmental deficits that may affect academic and social outcomes for individuals across the life span. In the period since the passage of PL 99-457, significant…

  9. Notetaking, Verbal Aptitude, & Listening Span: Factors Involved in Learning from Lectures.

    ERIC Educational Resources Information Center

    Walbaum, Sharlene D.

    Three variables (verbal aptitude, listening ability, and notetaking) that may mediate how much college students learn from a lecture were studied. Verbal aptitude was operationalized as a Verbal Scholastic Aptitude Test (VSAT) score. Listening ability was measured as the score on an auditory short-term memory task, using the serial running memory…

  10. Color Categories and Color Appearance

    ERIC Educational Resources Information Center

    Webster, Michael A.; Kay, Paul

    2012-01-01

    We examined categorical effects in color appearance in two tasks, which in part differed in the extent to which color naming was explicitly required for the response. In one, we measured the effects of color differences on perceptual grouping for hues that spanned the blue-green boundary, to test whether chromatic differences across the boundary…

  11. Performance of Deaf Children on Memory Tasks: Some Considerations.

    ERIC Educational Resources Information Center

    Green, Bernard L.

    1980-01-01

    This paper makes a start in the search for a fair test of prelingually deaf children's short-term visual memory ability by exploring the coding problems presented to them by the traditional digit-span test. It suggests that more research be devoted to the problem of stimulus-response compatibility. (Suthor/SJL)

  12. Bias in discriminating very mild dementia for older adults with different levels of education in Hong Kong.

    PubMed

    Chang, Jianfang; Tse, Chi-Shing; Leung, Grace Tak Yu; Fung, Ada Wai Tung; Hau, Kit-Tai; Chiu, Helen Fung Kum; Lam, Linda Chiu Wa

    2014-06-01

    Education has a profound effect on older adults' cognitive performance. In Hong Kong, some dementia screening tasks were originally designed for developed population with, on average, higher education. We compared the screening power of these tasks for Chinese older adults with different levels of education. Community-dwelling older adults who were healthy (N = 383) and with very mild dementia (N = 405) performed the following tasks: Mini-Mental State Examination, Alzheimer's Disease Assessment Scale-Cognitive subscales, Verbal Fluency, Abstract Thinking, and Visual/Digit Span. Logistic regression was used to examine the power of these tasks to predict Clinical Dementia Rating (CDR 0.5 vs. 0). Logistic regression analysis showed that while the screening power of the total scores in all tasks was similar for high and low education groups, there were education biases in some items of these tasks. The differential screening power in high and low education groups was not identical across items in some tasks. Thus, in cognitive assessments, we should exercise great caution when using these potentially biased items for older adults with limited education.

  13. Eye-fixation patterns of high- and low-span young and older adults: down the garden path and back again.

    PubMed

    Kemper, Susan; Crow, Angela; Kemtes, Karen

    2004-03-01

    Young and older adults' eye fixations were monitored as they read sentences with temporary ambiguities such as "The experienced soldiers warned about the dangers conducted the midnight raid." Their fixation patterns were similar except that older adults made many regressions. In a 2nd experiment, high- and low-span older adults were compared with high- and low-span young adults. Pint-pass fixations were similar, except low-span readers made many regressions and their total fixation times were longer. High-span readers also used the focus operator "only" (e.g., "Only experienced soldiers warned about the dangers.") to immediately resolve the temporary ambiguities. No age group differences were observed. These results are discussed with reference to theories of the role of working memory in sentence processing.

  14. Effects of lexical competition on immediate memory span for spoken words.

    PubMed

    Goh, Winston D; Pisoni, David B

    2003-08-01

    Current theories and models of the structural organization of verbal short-term memory are primarily based on evidence obtained from manipulations of features inherent in the short-term traces of the presented stimuli, such as phonological similarity. In the present study, we investigated whether properties of the stimuli that are not inherent in the short-term traces of spoken words would affect performance in an immediate memory span task. We studied the lexical neighbourhood properties of the stimulus items, which are based on the structure and organization of words in the mental lexicon. The experiments manipulated lexical competition by varying the phonological neighbourhood structure (i.e., neighbourhood density and neighbourhood frequency) of the words on a test list while controlling for word frequency and intra-set phonological similarity (family size). Immediate memory span for spoken words was measured under repeated and nonrepeated sampling procedures. The results demonstrated that lexical competition only emerged when a nonrepeated sampling procedure was used and the participants had to access new words from their lexicons. These findings were not dependent on individual differences in short-term memory capacity. Additional results showed that the lexical competition effects did not interact with proactive interference. Analyses of error patterns indicated that item-type errors, but not positional errors, were influenced by the lexical attributes of the stimulus items. These results complement and extend previous findings that have argued for separate contributions of long-term knowledge and short-term memory rehearsal processes in immediate verbal serial recall tasks.

  15. Performance impact of mutation operators of a subpopulation-based genetic algorithm for multi-robot task allocation problems.

    PubMed

    Liu, Chun; Kroll, Andreas

    2016-01-01

    Multi-robot task allocation determines the task sequence and distribution for a group of robots in multi-robot systems, which is one of constrained combinatorial optimization problems and more complex in case of cooperative tasks because they introduce additional spatial and temporal constraints. To solve multi-robot task allocation problems with cooperative tasks efficiently, a subpopulation-based genetic algorithm, a crossover-free genetic algorithm employing mutation operators and elitism selection in each subpopulation, is developed in this paper. Moreover, the impact of mutation operators (swap, insertion, inversion, displacement, and their various combinations) is analyzed when solving several industrial plant inspection problems. The experimental results show that: (1) the proposed genetic algorithm can obtain better solutions than the tested binary tournament genetic algorithm with partially mapped crossover; (2) inversion mutation performs better than other tested mutation operators when solving problems without cooperative tasks, and the swap-inversion combination performs better than other tested mutation operators/combinations when solving problems with cooperative tasks. As it is difficult to produce all desired effects with a single mutation operator, using multiple mutation operators (including both inversion and swap) is suggested when solving similar combinatorial optimization problems.

  16. 77 FR 27115 - Drawbridge Operation Regulation; Bayou Boeuf, Amelia, LA

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-05-09

    ... schedule that governs the Burlington Northern Santa Fe (BNSF) Railway Company swing span bridge across... docket, call Renee V. Wright, Program Manager, Docket Operations, telephone 202-366-9826. SUPPLEMENTARY...

  17. 17. DETAIL VIEW OF CUPOLA ATOP OPERATOR'S CABIN WHICH MOUNTS ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    17. DETAIL VIEW OF CUPOLA ATOP OPERATOR'S CABIN WHICH MOUNTS SIGNAL HORNS, WEATHER VANE - Sacramento River Bridge, Spanning Sacramento River at California State Highway 275, Sacramento, Sacramento County, CA

  18. Space applications of Automation, Robotics and Machine Intelligence Systems (ARAMIS). Volume 4: Application of ARAMIS capabilities to space project functional elements

    NASA Technical Reports Server (NTRS)

    Miller, R. H.; Minsky, M. L.; Smith, D. B. S.

    1982-01-01

    Applications of automation, robotics, and machine intelligence systems (ARAMIS) to space activities and their related ground support functions are studied, so that informed decisions can be made on which aspects of ARAMIS to develop. The specific tasks which will be required by future space project tasks are identified and the relative merits of these options are evaluated. The ARAMIS options defined and researched span the range from fully human to fully machine, including a number of intermediate options (e.g., humans assisted by computers, and various levels of teleoperation). By including this spectrum, the study searches for the optimum mix of humans and machines for space project tasks.

  19. Training improves reading speed in peripheral vision: is it due to attention?

    PubMed

    Lee, Hye-Won; Kwon, Miyoung; Legge, Gordon E; Gefroh, Joshua J

    2010-06-01

    Previous research has shown that perceptual training in peripheral vision, using a letter-recognition task, increases reading speed and letter recognition (S. T. L. Chung, G. E. Legge, & S. H. Cheung, 2004). We tested the hypothesis that enhanced deployment of spatial attention to peripheral vision explains this training effect. Subjects were pre- and post-tested with 3 tasks at 10° above and below fixation-RSVP reading speed, trigram letter recognition (used to construct visual-span profiles), and deployment of spatial attention (measured as the benefit of a pre-cue for target position in a lexical-decision task). Groups of five normally sighted young adults received 4 days of trigram letter-recognition training in upper or lower visual fields, or central vision. A control group received no training. Our measure of deployment of spatial attention revealed visual-field anisotropies; better deployment of attention in the lower field than the upper, and in the lower-right quadrant compared with the other three quadrants. All subject groups exhibited slight improvement in deployment of spatial attention to peripheral vision in the post-test, but this improvement was not correlated with training-related increases in reading speed and the size of visual-span profiles. Our results indicate that improved deployment of spatial attention to peripheral vision does not account for improved reading speed and letter recognition in peripheral vision.

  20. General Slowing and Education Mediate Task Switching Performance Across the Life-Span

    PubMed Central

    Moretti, Luca; Semenza, Carlo; Vallesi, Antonino

    2018-01-01

    Objective: This study considered the potential role of both protective factors (cognitive reserve, CR) and adverse ones (general slowing) in modulating cognitive flexibility in the adult life-span. Method: Ninety-eight individuals performed a task-switching (TS) paradigm in which we adopted a manipulation concerning the timing between the cue and the target. Working memory demands were minimized by using transparent cues. Additionally, indices of cognitive integrity, depression, processing speed and different CR dimensions were collected and used in linear models accounting for TS performance under the different time constraints. Results: The main results showed similar mixing costs and higher switching costs in older adults, with an overall age-dependent effect of general slowing on these costs. The link between processing speed and TS performance was attenuated when participants had more time to prepare. Among the different CR indices, formal education only was associated with reduced switch costs under time pressure. Discussion: Even though CR is often operationalized as a unitary construct, the present research confirms the benefits of using tools designed to distinguish between different CR dimensions. Furthermore, our results provide empirical support to the assumption that processing speed influence on executive performance depends on time constraints. Finally, it is suggested that whether age differences appear in terms of switch or mixing costs depends on working memory demands (which were low in our tasks with transparent cues). PMID:29780341

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