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991.
The primary aim of this paper is to analyze the concept of degrees of causal contribution for actual events and examine the
way in which it can be formally defined. This should go some way to filling out a gap in the legal and philosophical literature
on causation. By adopting the conception of a cause as a necessary element of a sufficient set (the so-called NESS test) we
show that the concept of degrees of causation can be given clear and even empirical meaning. We then apply a game theoretical
framework to derive a measure of causal contribution. Our favoured measure turns out to be a generalised version of the normalized
Penrose–Banzhaf index of voting power. 相似文献
992.
The aim of this investigation was to examine the time course and the relative contributions of perceptual and post-perceptual processes to categorical perception (CP) of color. A visual oddball task was used with standard and deviant stimuli from same (within-category) or different (between-category) categories, with chromatic separations for within- and between-category stimuli equated in Munsell Hue. CP was found on a behavioral version of the task, with faster RTs and greater accuracy for between- compared to within-category stimuli. On a neurophysiological version of the task, event-related potentials (ERPs) showed earlier latencies for P1 and N1 components at posterior locations to between- relative to within-category deviants, providing novel evidence for early perceptual processes on color CP. Enhanced P2 and P3 waves were also found for between- compared to within-category stimuli, indicating a role for later post-perceptual processes. 相似文献
993.
Several studies have demonstrated that acquired expertise influences aesthetic judgments. In this paradigm we used functional magnetic resonance imaging (fMRI) to study aesthetic judgments of visually presented architectural stimuli and control-stimuli (faces) for a group of architects and a group of non-architects. This design allowed us to test whether level of expertise modulates neural activity in brain areas associated with either perceptual processing, memory, or reward processing. We show that experts and non-experts recruit bilateral medial orbitofrontal cortex (OFC) and subcallosal cingulate gyrus differentially during aesthetic judgment, even in the absence of behavioural aesthetic rating differences between experts and non-experts. By contrast, activity in nucleus accumbens (NAcc) exhibits a differential response profile compared to OFC and subcallosal cingulate gyrus, suggesting a dissociable role between these regions in the reward processing of expertise. Finally, categorical responses (irrespective of aesthetic ratings) resulted in expertise effects in memory-related areas such as hippocampus and precuneus. These results highlight the fact that expertise not only modulates cognitive processing, but also modulates the response in reward related brain areas. 相似文献
994.
Performance Indicators in Math: Implications for Brief Experimental Analysis of Academic Performance
Brief experimental analysis (BEA) can be used to specify intervention characteristics that produce positive learning gains
for individual students. A key challenge to the use of BEA for intervention planning is the identification of performance
indicators (including topography of the skill, measurement characteristics, and decision criteria) that meaningfully relate
to longer term success in the learning environment. This study investigates the utility of various curriculum-based assessment
and measurement estimates of mathematics performance for predicting functional outcomes (i.e., retention of learned skills
over time and faster learning of related content in the future). All children in grades 2–5 at the participating school participated
in protocol-based computational fluency-building intervention 4 days per week for an entire school year. Specific criteria
were applied each week to systematically increase intervention difficulty classwide according to a pre-established sequence
of computational skill objectives. Three measurements were routinely obtained. Each week children completed a timed probe
of the skill for which intervention was currently occurring and a timed probe of previously mastered skills from the sequence
of computational skill objectives. Each month, all children completed a timed probe of mathematics skills representing computational
skills that students were expected to master by year’s end at each grade level. At all grade levels, learning a skill that
appeared early in the hierarchy or sequence of skills related positively to learning of future related and more complex computational
skills. Fluency criteria were specified that predicted retention of the skill over several months. 相似文献
995.
Ann Kathleen Burlew Candace S. Johnson Amanda M. Flowers Bridgette J. Peteet Kyna D. Griffith-Henry Natasha D. Buchanan 《Journal of child and family studies》2009,18(6):680-689
The consequences of the early onset of substance use on later outcomes are a public health concern. In the present study,
we examined neighborhood risk factors as a possible predictor of the onset of substance use in adolescents. In addition, we
assessed the potential buffering effects of parental supervision on the relationship between neighborhood risk and the onset
of substance use. The participants included 95, abstinent, African American 6th graders (mean age = 11.5 years) who enrolled
in one site of a national, multi-site study of high-risk youth participating in a federally sponsored program. In the 6th
and 8th grades, the participants completed self-report measures regarding substance use, perceived negative neighborhood activities
and parental supervision. Logistic regression analyses demonstrated that both exposure to negative neighborhood activities
and low parental supervision increase the onset of substance use by the 8th grade among African American adolescents. However,
the results suggested that parents can protect their adolescents from the impact of exposure to adverse neighborhood factors
by providing appropriate supervision. 相似文献
996.
Amanda W. Harrell Sterett H. Mercer Melissa E. DeRosier 《Journal of child and family studies》2009,18(4):378-387
We evaluated the efficacy of a social skills training intervention designed to improve adolescents’ social, emotional and
behavioral adjustment, Social Skills Group Intervention-Adolescent (S.S.GRIN-A). Seventy-four adolescents (ages 13–16 years)
and their parents were randomly assigned to either the treatment group (N = 40) or a wait-list control group (N = 34). Adolescents in the treatment and control groups were compared on global self-concept, social self-efficacy, internalizing
problems, and externalizing problems pre- and post-intervention. Youth in the treatment group demonstrated enhanced global
self-concept, increased social self-efficacy, and decreased internalizing problems as compared to youth in the control group.
No differences in externalizing behavior were found. We discuss the effectiveness of S.S.GRIN-A as a general program designed
for addressing a range of adjustment issues and social skill deficits in adolescents. 相似文献
997.
Martin P Baenziger J Macdonald M Siegler IC Poon LW 《Journal of Adult Development》2009,16(4):199-208
This study assessed engaged lifestyle activities (e.g., volunteering, traveling, and public speaking) for centenarians of
the Georgia Centenarian Study. A total of 285 centenarians and near-centenarians (i.e., 98 years and older) and their proxy
informants participated in this study. The Mini-Mental Status Examination (MMSE) was assessed for all centenarians, and proxy
informants reported on lifestyle activities and personality traits of the centenarians. Results suggested that participants
who had volunteered, traveled, and those who had given public talks and balanced their checkbooks were more likely to show
relatively high mental status scores (i.e., MMSE > 17). Personality traits were found to be moderators in the relationship
between engaged lifestyle and mental status: Participants with high levels of Emotional Stability, Extraversion, Openness,
and Conscientiousness and with high levels of engaged lifestyle were more likely to show relatively high mental status scores
(i.e., MMSE > 17), whereas participants with low levels of Emotional Stability, Extraversion, Openness, Agreeableness, and
Conscientiousness and with low levels of engaged lifestyle were more likely to show relatively low mental status scores (i.e.,
MMSE < 18). The results suggest that engaged lifestyle, particularly in combination with personality traits, plays an important
role in the level of cognitive functioning among oldest old adults. 相似文献
998.
Samuel Shaki Martin H. Fischer William M. Petrusic 《Psychonomic bulletin & review》2009,16(2):328-331
This study compared the spatial representation of numbers in three groups of adults: Canadians, who read both English words
and Arabic numbers from left to right; Palestinians, who read Arabic words and Arabic-Indic numbers from right to left; and
Israelis, who read Hebrew words from right to left but Arabic numbers from left to right. Canadians associated small numbers
with left and large numbers with right space (the SNARC effect), Palestinians showed the reverse association, and Israelis
had no reliable spatial association for numbers. These results suggest that reading habits for both words and numbers contribute
to the spatial representation of numbers. 相似文献
999.
Scholz U La Marca R Nater UM Aberle I Ehlert U Hornung R Martin M Kliegel M 《Neurobiology of learning and memory》2009,91(1):89-92
Acute stress has been found to have negative and implementation intentions (IIs) to have positive effects on cognitive performance. This study was the first to examine the effects of IIs on executive action control under acute psychosocial stress. Forty-two male subjects aged 21-39 years were randomly assigned to the Trier Social Stress Test (TSST) versus a rest condition. In addition, the instruction to the executive task (a go no-go task) was manipulated (IIs versus standard instruction). After the stress test, a dual-task procedure including a go no-go task was conducted. The TSST resulted in increases in cortisol response, heart rate and state anxiety compared to the rest condition. Acute stress significantly impaired go no-go performance, but only in the group without IIs. We conclude that under acute stress conditions executive functioning is reduced, but the use of IIs can be an effective strategy to overcome this negative effect. 相似文献
1000.