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971.
Effects of environmental variables on performance may be mediated by individual stress states. In this study the effects of jet-aircraft engine noise and signal salience on vigilance performance and self-reported stress state were examined. One hundred and ninety-two (96 female and 96 male) participants were randomly assigned to four experimental conditions consisting of 48 participants each resulting from the factorial combination of signal salience (high and low salience signals) and noise (95 dBA intermittent aircraft noise or quiet). Performance metrics and self-reported stress state (Task Engagement, Distress, and Worry) were collected. Performance in the noise conditions was significantly better than in the quiet conditions. Performance in the high salience conditions was significantly better than the low salience conditions. Noise elevated Task Engagement and low signal salience elevated Distress. Moreover, structural equation model analyses were used to examine stress state mediation between the experimental variables and performance. These analyses indicated Engagement mediates between noise and vigilance performance. 相似文献
972.
Two experiments are performed to investigate how luminance change contributes to prioritized selection of new over old elements. Experiment 1 demonstrates that observers prioritize items that undergo a luminance change irrespective of the direction of that change. Experiment 2 shows that foreknowledge concerning the direction of luminance change signaling the target does not allow observers to prioritize the selection of luminance onsets over offsets and vice versa. The results suggest that prioritized selection of new over old elements is mediated by a general mechanism that is sensitive to luminance change, irrespective of its direction. 相似文献
973.
974.
Lisa Winborn‐Kemmerer Joel E. Ringdahl David P. Wacker Kana Kitsukawa 《Journal of applied behavior analysis》2009,42(1):185-189
Preference for mand topography was evaluated for 2 individuals with developmental disabilities who exhibited problem behavior. The results of a functional analysis showed that each participant's problem behavior was maintained by social reinforcement. Participants were taught two novel mand topographies for the same functional reinforcer, and each proved to be effective in reducing problem behavior. Finally, preference for mand topography was assessed within a concurrent‐schedules design. Results indicated that functional communication training was an effective treatment, regardless of the mand used, and that each participant demonstrated a preference for one mand topography relative to the other. 相似文献
975.
David A Wilder Martisa Register Stanley Register Vedrana Bajagic Pamela L Neidert Rachel Thompson 《Journal of applied behavior analysis》2009,42(4):877-882
A functional analysis suggested that rumination exhibited by an adult with autism was maintained by automatic reinforcement. Next, a preference assessment with three flavor sprays (i.e., flavored sprays used by dieters) showed that apple pie spray was most preferred. Finally, the effects of fixed‐time delivery of the apple pie spray on levels of rumination were evaluated. The spray reduced rumination, and the participant was taught to self‐administer the spray. 相似文献
976.
One of the major functions of academic journals is to contribute to the evaluation of research activities and scientists. Invented more than 50 years ago, the ISI impact factor (IF) became the most important indicator of the quality of journals, in spite of well-known problems and critics such as the over-representation of English-language journals. This is a specific problem for French publishers and scientists; publishing in French is not valorising. Since 2007, the new SCImago Journal Rank Indicator (SJR) offers an alternative to the IF. SJR applies the Google algorithm (PageRank) to the journals of the SCOPUS bibliographic database that indexes more journals than ISI Web of Science. The goal of our study is to compare the two indicators for French academic journals, with three questions: Which is the coverage of French journals by ISI and SCOPUS (title number, scientific disciplines)? Which are the differences of the two indicators IF and SJR for the ranking of French journals? How do they cover the French academic journal publishing market (representativity)? The results of our study of 368 French journals with IF and/or SJR are in favour of the usage of the new indicator, at least as a complement to the IF. (1) Coverage: 166 journals are indexed by ISI (45%), 345 journals are indexed by SCOPUS (94%), 143 journals are indexed by both (39%). 82% of the journals are from STM, 18% are from SS&H. In particular, SCOPUS covers much better the medical and pharmacological sciences. (2) Ranking: The correlation of IF and SJR for the 143 journals with both indicators is high (0.76). The IF better differentiates the journals than the SJR indicator (155 vs. 89 rankings). On the other side, because of the larger source database, more French titles become visible on an international level through SJR than through IF. (3) Representativity: The SJR is more interesting and representative of the French academic journal publishing market than the IF (19% vs. 9%), especially for STM titles (38% vs. 19%), much less for SS&H titles (6% vs. 2%). Nevertheless, ISI (Web of Science) and SCOPUS index journals from only a small part of the French academic publishers (10%–20%). Again, SCOPUS is more representative than the ISI dababase (17% of the publishers vs. 10%). Methodological problems and perspective of a multidimensional evaluation are discussed. Our study compares the ISI impact factor (IF) with the new SJR for 368 French academic journals with IF and/or SJR. The results: The SJR coverage is better than of the IF (94% vs. 45%), especially in medical sciences. The correlation of IF and SJR for journals with both indicators is high (0.76). The IF better differentiates the journals than the SJR indicator (155 vs. 89 rankings). The SJR coverage is more representative of the French academic journal publishing market than ISI/IF (19% vs. 9%), especially for STM titles (38% vs. 19%), less for SS&H titles (6% vs. 2%). 相似文献
977.
The aim of this study is to establish a link between the father-child attachment and the quality of the sibling relationships for school-age children, by taking into account the theoretical and methodological evolution of this specific attachment. Fifty-seven fathers answered the Questionnaire of Opening up to the World [Défi jeunesse, 8 (2002) 6–12], which defines the father-child attachment (or activation) on two axes: the stimulation (social, cognitive and emotional) and the paternal control exercised over the child. The Questionnaire “Sibling Relationships in Young Children” [Troupel, O., 2006. Attachement fraternel, styles de relations et des interactions de tutelle au sein des fratries de jeunes enfants : effet modulateur de la représentation des relations fraternelles de l’aîné. Thèse de doctorat nouveau régime, université de Toulouse–Le-Mirail] gives insight into the quality of sibships. Children, with a secure attachment to their father, demonstrate a higher level of cooperation with their elder sibling than the other children, in particular those which receive excessive control and little stimulation from their fathers. The hypothesis that the stimulation of the second-born child by the father on the peer side is directly linked to the quality of the sibships is not confirmed. Other results on father-child attachment and sibships are discussed. 相似文献
978.
A. Soubelet 《Psychologie Fran?aise》2009,(4):363-378
Although intuitively plausible, the evidence relevant to the mental exercise hypothesis is currently mixed. One of the main controversial issues concerning the investigation of this hypothesis has to do with how cognitive stimulation is assessed. The mental exercise hypothesis was here tested with a subjective and self-reported measure of cognitive stimulation. Overall, results have supported that a greater engagement in cognitively stimulating activities was associated with higher levels of cognitive functioning. However, the rate of cognitive decline with advancing age was not reduced for people who were more mentally active. Of great interest, the subjective measure of cognitive engagement have supported that cognitive demands assessed by participants on activities varied as a function of participants’ cognitive resources: lower cognitive resources were associated with lower perceived cognitive demands. 相似文献
979.
Laine M Tuokkola T Hiltunen J Vorobyev V Bliss I Baddeley A Rinne JO 《Scandinavian journal of psychology》2009,50(1):33-40
Using positron emission tomography (PET), we explored the neural correlates of an executive function, dual tasking, in patients with amnestic mild cognitive impairment (aMCI) and in elderly controls. The experiment employed simple auditory and visual tasks that were presented both in isolation and simultaneously to create a task condition requiring enhanced attentional control. Behaviorally, both groups performed well, albeit the patients made more errors on the visual task. The PET analysis focused at prefrontal regions where group differences in task-related activation patterns were expected. During dual task performance, the patients showed attenuated activity in the left inferior frontal region when compared to the controls. This suggests abnormalities in the neural processes underlying attentional control in aMCI. 相似文献
980.
Michelle Y. Kibby Judith M. Kroese Hillery Krebbs Crystal E. Hill George W. Hynd 《Brain and language》2009,111(1):46-54
Limited research has been conducted on the structure of the pars triangularis (PT) in dyslexia despite functional neuroimaging research finding it may play a role in phonological processing. Furthermore, research to date has not examined PT size in ADHD even though the right inferior frontal region has been implicated in the disorder. Hence, one of the purposes of this study was to examine the structure of the PT in dyslexia and ADHD. The other purposes included examining the PT in relation to overall expressive language ability and in relation to several specific linguistic functions given language functioning often is affected in both dyslexia and ADHD. Participants included 50 children: 10 with dyslexia, 15 with comorbid dyslexia/ADHD, 15 with ADHD, and 10 controls. Using a 2 (dyslexia or not) × 2 (ADHD or not) MANCOVA, findings revealed PT length and shape were comparable between those with and without dyslexia. However, children with ADHD had smaller right PT lengths than those without ADHD, and right anterior ascending ramus length was related to attention problems in the total sample. In terms of linguistic functioning, presence of an extra sulcus in the left PT was related to poor expressive language ability. In those with adequate expressive language functioning, left PT length was related to phonological awareness, phonological short-term memory and rapid automatic naming (RAN). Right PT length was related to RAN and semantic processing. Further work on PT morphology in relation to ADHD and linguistic functioning is warranted. 相似文献