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101.
In visual search tasks, the relative proportions of target-present and -absent trials have important effects on behavior. Miss error rates rise as target prevalence decreases (Wolfe, Horowitz, & Kenner, Nature 435, 439-440, 2005). At the same time, search termination times on target-absent trials become shorter (Wolfe & Van Wert, Current Biology 20, 121-124, 2010). These effects must depend on some implicit or explicit knowledge of the current prevalence. What is the nature of that knowledge? In Experiment 1, we conducted visual search tasks at three levels of prevalence (6%, 50%, and 94%) and analyzed performance as a function of "local prevalence," the prevalence over the last n trials. The results replicated the usual effects of overall prevalence but revealed only weak or absent effects of local prevalence. In Experiment 2, the overall prevalence in a block of trials was 20%, 50%, or 80%. However, a 100%-valid cue informed observers of the prevalence on the next trial. These explicit cues had a modest effect on target-absent RTs, but explicit expectation could not explain the full prevalence effect. We conclude that observers predict prevalence on the basis of an assessment of a relatively long prior history. Each trial contributes a small amount to that assessment, and this can be modulated but not overruled by explicit instruction. 相似文献
102.
Although growth in head circumference (HC) during infancy is known to predict later childhood outcomes, the mechanisms underlying this association with later sociocognitive abilities remain undetermined. Thus, using a sample of 241 pairs of normally developing Japanese twins, this study investigated the underpinnings of the association between HC growth (difference between HC at birth and at 10 months) and sociocognitive abilities at 19 months as measured by 10 items from the M-CHAT. Phenotypic correlations between HC at birth and sociocognitive abilities and between HC growth and sociocognitive abilities were marginal and not significant. However, multivariate genetic analyses using Cholesky decomposition revealed that genetic influences on HC growth and those on sociocognitive abilities were negatively associated. On the other hand, shared and nonshared environmental influences on HC growth were positively associated with influences on sociocognitive abilities. Genetic and environmental influences on HC at birth were not significantly associated with influences on sociocognitive abilities. These results help to clarify the role of brain growth during infancy in the subsequent development of sociocognitive abilities and highlight the importance of examining the different roles of genetic and environmental influences in studies of these areas. 相似文献
103.
Previous studies have noted that writing processes are impaired by task-irrelevant background sound. However, what makes sound distracting to writing processes has remained unaddressed. The experiment reported here investigated whether the semanticity of irrelevant speech contributes to disruption of writing processes beyond the acoustic properties of the sound. The participants wrote stories against a background of normal speech, spectrally-rotated speech (i.e., a meaningless sound with marked acoustic resemblance to speech) or silence. Normal speech impaired quantitative (e.g., number of characters produced) and qualitative/semantic (e.g., uncorrected typing errors, proposition generation) aspects of the written material, in comparison with the other two sound conditions, and it increased the duration of pauses between words. No difference was found between the silent and the rotated-speech condition. These results suggest that writing is susceptible to disruption from the semanticity of speech but not especially susceptible to disruption from the acoustic properties of speech. 相似文献
104.
Multisystemic Therapy (MST) has been found to be effective in reducing youth antisocial behavior, but little is known about the process and impact of MST from the perspective of families themselves. This qualitative study explored parents' and young people's experiences of MST, focusing on aspects of the intervention that promoted or limited change. Thirty-seven semistructured interviews were conducted with a consecutive sample of 21 families (21 parent interviews, 16 young people) who had participated in a randomized controlled trial of MST for young offenders in the United Kingdom. Thematic analysis yielded 10 themes, organized into two domains: (a) engagement in MST and initial processes of change captures the central importance of the therapeutic relationship and the MST engagement model in families' positive experiences of MST; and (b) outcomes are complex reflects the range of positive outcomes reported (notably increased parental confidence and skills, improved family relationships, a return to education, and greater reflection and aspiration on the part of the young person) and mixed behavior outcomes. Even when the young person had reoffended, respondents indicated a range of other benefits for the family. The findings support the MST theory of change as well as point to some outcomes not usually measured in MST outcome studies. They also suggest some adaptations that may increase the impact of the intervention, including more attention to the influence of deviant peers, and ongoing support for families struggling to maintain strategies beyond the prescribed treatment period. 相似文献
105.
Credé M Harms P Niehorster S Gaye-Valentine A 《Journal of personality and social psychology》2012,102(4):874-888
Researchers often use very abbreviated (e.g., 1-item, 2-item) measures of personality traits due to their convenience and ease of use as well as the belief that such measures can adequately capture an individual's personality. Using data from 2 samples (N = 437 employees, N = 355 college students), we show that this practice, particularly the use of single-item measures, can lead researchers to substantially underestimate the role that personality traits play in influencing important behaviors and thereby overestimate the role played by new constructs. That is, the use of very short measures of personality may substantially increase both the Type 1 and Type 2 error rates. We argue that even slightly longer measures can substantially increase the validity of research findings without significant inconvenience to the researcher or research participants. 相似文献
106.
Previous research suggests that the own-race bias (ORB) in memory for faces is a result of other-race faces receiving less visual attention at encoding. As women typically display an own-gender bias in memory for faces and men do not, we investigated whether face gender and sex of viewer influenced visual attention and memory for own- and other-race faces, and if preferential viewing of own-race faces contributed to the ORB in memory. Participants viewed pairs of female or male own- and other-race faces while their viewing time was recorded. Afterwards, they completed a surprise memory test. We found that (1) other-race males received the initial focus of attention, (2) own-race faces were viewed longer than other-race faces over time, although the difference was larger for female faces, and (3) even though longer viewing time increased the probability of remembering a face, it did not explain the magnified ORB in memory for female faces. Importantly, these findings highlight that face gender moderates attentional responses to and memory for own- and other-race faces. 相似文献
107.
The study aims at investigating the dynamics of visual information processing during sequential control of attentional selection. By combining two different traditional paradigms we show for the first time that during rapid selection of visual targets, encoding of a new target stimulus is facilitated by suppression of the preceding relevant stimulus category (Backward Blink; BB). Such inhibition would operate to reduce interference from previously stored information, in order to facilitate the instantiation of a new attentional episode. Results suggest that the same underlying inhibitory mechanism might contribute to two different attentional effects, specifically, the switch cost and the Attentional Blink, suggesting a general inhibitory mechanism of attentional control, with broad implications for understanding how the brain perceives any task-relevant stimulus. 相似文献
108.
This study examined links between two distinct facets of empathy-empathic accuracy and perceived empathic effort-and one's own and one's partner's relationship satisfaction. Using a video recall procedure, participants (n = 156 couples in committed relationships) reported on their own emotions and their perceptions of partners' emotions and partners' empathic intentions during moments of high affect in laboratory-based discussions of upsetting events. Partners' data were correlated as a measure of how accurately they were able to read what the other was feeling and to what degree they felt the other was trying to be empathic at those moments. The perception of empathic effort by one's partner was more strongly linked with both men's and women's relationship satisfaction than empathic accuracy. Men's relationship satisfaction was related to the ability to read their partners' positive emotions accurately, whereas women's relationship satisfaction was related to their partners' ability to read women's negative emotions accurately. Women's ability to read their husbands' negative emotions was positively linked to both men's and women's relationship satisfaction. Findings suggest that the perception of a partner's empathic effort-as distinct from empathic accuracy-is uniquely informative in understanding how partners may derive relationship satisfaction from empathic processes. When working with couples in treatment, heightening partners' perceptions of each other's empathic effort, and helping partners learn to demonstrate effort, may represent particularly powerful opportunities for improving satisfaction in relationships. 相似文献
109.
Exploring the associations between coping patterns for everyday stressors and mental health in young schoolchildren 总被引:1,自引:0,他引:1
The purposes of this study were to explore the structure of coping with everyday stressors in a young nonclinical population and examine the relationship between coping and mental health. A total of 1324 children from 91 second-grade classes in 35 schools participated. Mental health was assessed using the parent and teacher forms of the Strengths and Difficulties Questionnaire (Goodman, 1997), and coping was assessed by the Kidcope (Spirito et al., 1988) self-report checklist. Exploratory and confirmatory factor analyses suggested a three-factor structure of coping. Latent-variable regression analysis indicated that coping categories including both active and emotional strategies were associated with fewer mental health problems, whereas withdrawal and oppositional coping strategies were associated with greater mental health problems. With some important exceptions, the results replicated previous studies of adults and adolescents. The need for new, more comprehensive coping assessments is highlighted. 相似文献
110.
BackgroundIntolerance of uncertainly (IU), cognitive avoidance (CA) and positive beliefs about worry (PB) independently predict worry frequency in older adolescents and adults, and when targeted together in treatment produce significant reductions in both worry and anxiety in this age range. The present study addresses a gap in the literature by testing whether a cognitive model of excessive worry and anxiety incorporating these process variables is applicable to children and adolescents.MethodPrimary and secondary school students (n = 515; aged 7–19 years) completed modified self-report measures of worry frequency, anxiety, IU, CA and PB and a path analysis undertaken to test whether IU was a higher order variable for CA and PB and whether the relationship between IU/CA/PB and anxiety was mediated by worry frequency.ResultsSignificant (bivariate) correlations were observed between the measures of IU, PB, CA, worry and anxiety across the age range. However separate path models had to be fitted for children (aged 7–12 years) and adolescents (aged 13–19) with PB being dropped from the child model. CA was related to anxiety only through worry in children while IU showed direct paths to worry and anxiety in both children and adolescents.ConclusionsCognitive models of persistent worry in adults and older adolescents may, with some modification, have applicability to children. Further testing and refinement of these cognitive models of worry may lead to improvements in existing treatments for anxious youth. 相似文献