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971.
Katherine A. MacLean Stephen R. Aichele David A. Bridwell George R. Mangun Ewa Wojciulik Clifford D. Saron 《Attention, perception & psychophysics》2009,71(5):1042-1058
The ability to remain vigilant over long periods of time is critical for many everyday tasks, but controlled studies of visual sustained attention show that performance declines over time when observers are required to respond to rare stimulus events (targets) occurring in a sequence of standard stimulus events (nontargets). When target discrimination is perceptually difficult, this vigilance decrement manifests as a decline in perceptual sensitivity. We examined whether sudden-onset stimuli could act as exogenous attentional cues to improve sensitivity during a traditional sustained attention task. Sudden-onset cues presented immediately before each stimulus attenuated the sensitivity decrement, but only when stimulus timing (the interstimulus interval [ISI]) was constant. When stimulus timing was variable, exogenous cues increased overall sensitivity but did not prevent performance decline. Finally, independent of the effects of sudden onsets, a constant ISI improved vigilance performance. Our results demonstrate that exogenous attention enhances perceptual sensitivity during vigilance performance, but that this effect is dependent on observers’ being able to predict the timing of stimulus events. Such a result indicates a strong interaction between endogenous and exogenous attention during vigilance. We relate our findings to a resource model of vigilance, as well as to theories of endogenous and exogenous attention over short time periods. 相似文献
972.
973.
International Journal for Philosophy of Religion - 相似文献
974.
975.
976.
George Vass 《Heythrop Journal》2004,45(4):477-485
977.
978.
George E. Weaver 《Studia Logica》1994,53(2):325-342
This paper introduces the notion of syntactic feature to provide a unified treatment of earlier model theoretic proofs of both the compactness and interpolation theorems for a variety of two valued logics including sentential logic, first order logic, and a family of modal sentential logic includingM,B,S
4 andS
5. The compactness papers focused on providing a proof of the consequence formulation which exhibited the appropriate finite subset. A unified presentation of these proofs is given by isolating their essential feature and presenting it as an abstract principle about syntactic features. The interpolation papers focused on exhibiting the interpolant. A unified presentation of these proofs is given by isolating their essential feature and presenting it as a second abstract principle about syntactic features. This second principle reduces the problem of exhibiting the interpolant to that of establishing the existence of a family of syntactic features satisfying certain conditions. The existence of such features is established for a variety of logics (including those mentioned above) by purely combinatorial arguments.Presented byMelvin Fitting 相似文献
979.
George P. Knight Lynn M. Virdin Katheryn A. Ocampo Mark Roosa 《American journal of community psychology》1994,22(6):767-783
Recently there has been concern over the need for mental health research within ethnic minority populations, particularly
Hispanic populations. Although there has been research focusing upon the similarity of mental health problems among Hispanic
and Anglo-American samples, the absence of information regarding the cross-ethnic measurement equivalence of the assessment
tools used in these comparisons seriously limits the interpretability of these findings. The two reported studies were designed
to (a) examine the cross-ethnic functional and scalar equivalence of several mental health measures by examining the interrelations
of these mental health indicators and examining the regression equations using negative life events to predict mental health
outcomes; and (b) compare several mental health indicators among Hispanic and Anglo-American 8- to 14-year-old children. Findings
suggest considerable cross-ethnic functional and scalar equivalence for the measure of depression, conduct disorders, and
negative life events. In addition, findings indicate that the Hispanic children scored higher in depression than did the Anglo-American
children, but this difference could be a function of differences in SES. The reader is cautioned that the present samples
included only English-speaking and primarily Mexican American children.
This study was funded by the National Institute for Mental Health Grant 2-P50-MH39246-06 to support the Preventive Intervention
Research Center at Arizona State University. The authors gratefully acknowledge the contributions made by Tim Ayers, Carolyn
Berg, Leah Gensheimer, Joanne Gersten, Nancy Groppenbacher, Lisa Jack, Lillian Lengua, Marcia Michaels, Irwin Sandler, and
Jerome Short. 相似文献
980.
John Patton George Fitchet Carrie Doehring Ph.D. Henry T. Close Arlene Brewster PhD Theodore R. Stoneberg Ph.D. Gary C. Augustin Ph.D. Charles Hart Homer Bain Ph.D. James B. Ashbrook Stuart A. Plummer Alexandra M. Hepburn Ph.D. 《Pastoral Psychology》1994,42(5):365-391
Private Practice Youngstown, Ohio 44512 相似文献