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281.
Ageism has resulted in overstated expectations regarding the inevitable deterioration in human capabilities, such as visual perception, with age (Rowe and Kahn in Science, 237, 143?C149, 1987; Grant in Health and Social Work, 21, 9?C15, 1996). Human visual perception, however, is of a largely constructive nature, evidenced in the complementary interactions between top-down inputs (e.g., expectations) and bottom-up stimuli (Engel et al. in National Review of Neuroscience, 2(10), 704?C716, 2001; Miller and Cohen in, Annual Review of Neuroscience, 24, 167-202, 2001). Based on this constructive nature, we hypothesized that visual perception may be better than is typically expected. In three experiments, we demonstrated the malleability of visual acuity using a conditioning procedure involving manipulations in bottom-up stimuli. Experimental groups read a book excerpt with one letter in decreased font size, while the control groups read the same book excerpt with all letters in the same font size. Experiment 1 (N?=?112) examined whether visual acuity could be enhanced for a specific letter. Experiment 2 (N?=?70) assessed whether visual acuity could be enhanced for a non-conditioned letter, while Experiment 3 (N?=?108) evaluated whether the visual conditioning effects would transfer to all non-conditioned letters. Visual acuity for experimental groups was significantly better than that in the control groups, speaking to the general malleability of our visual sense.  相似文献   
282.
Little is known about positive development across the transition from adolescence to young adulthood. The purpose of this paper was to use longitudinal data from a large community sample, the Australian Temperament Project, to investigate prospective associations between positive development at age 19?C20?years and changes in social, health, and behavioral outcomes at 23?C24?years. Data from 890 young adults (61.7% women) were analyzed using path analysis. Emotional health, physical well-being, friendship quality, reduced antisocial behavior, and positive development in young adulthood were predicted by higher levels of positive development in late adolescence, after controlling for baseline levels of respective outcomes, gender, and family socioeconomic status. Parent relationship quality and alcohol use were not significantly predicted. Based on these findings, interventions promoting positive development during adolescence should be investigated as a potential means of yielding positive social, health, and behavioral consequences well into young adulthood.  相似文献   
283.
Autobiographical memory research documents increased access in the number of memories recalled by emerging adults (ages 18–25) with stable, clearly defined self-concepts. Very little research has examined the relationship between self-concept clarity and the episodic and semantic components of emerging adults’ autobiographical recollections. This study examined the relationship between episodic and semantic autobiographical memory and self-concept clarity in 100 undergraduate students. Contrary to previous findings, which indicated that stable self-beliefs may be used to facilitate access to episodic memories, the results suggested that self-concept clarity may not be associated with memory specificity. Instead, self-concept clarity was associated with recall of events involving cooperative social interactions. Results further showed that older age was associated with higher SCC. The implications of these results are discussed within the context of the theoretical literature concerning the relation between autobiographical memory and the development of the self-concept during emerging adulthood.  相似文献   
284.
Interactive display systems give users flexibility to tailor their visual displays to different tasks and situations. However, in order for such flexibility to be beneficial, users need to understand how to tailor displays to different tasks (to possess "metarepresentational competence"). Recent research suggests that people may desire more complex and realistic displays than are most effective (Smallman & St. John, 2005). In Experiment 1, undergraduate students were tested on a comprehension task with geospatial displays (weather maps) that varied in the number of extraneous variables displayed. Their metacognitive judgments about the relative effectiveness of the displays were also solicited. Extraneous variables slowed response time and increased errors, but participants favored complex maps that looked more realistic about one third of the time. In Experiment 2, the eye fixations of undergraduate students were monitored as they performed the comprehension task. Complex maps that looked more realistic led to more eye fixations on both task-relevant and task-irrelevant regions of the displays. Experiment 3 compared performance of experienced meteorologists and undergraduate students on the comprehension and metacognitive tasks. Meteorologists were as likely as undergraduate students to prefer geographically complex (realistic) displays and more likely than undergraduates to opt for displays that added extraneous weather variables. However, meteorologists were also slower and less accurate with complex than with simple displays. This work highlights the importance of empirically testing principles of visual display design and suggests some limits to metarepresentational competence.  相似文献   
285.
Objective: To empirically identify the appropriate symptom threshold for hyperactivity-impulsivity for diagnosis of ADHD in adults. Method: Participants were 88 adults (M [SD] age = 41.69 [11.78] years, 66% female, 16% minority) meeting formal DSM-IV criteria for ADHD combined or predominantly inattentive subtypes based on a structured diagnostic interview keyed to DSM-IV (Conners' Adult ADHD Diagnostic Interview for DSM-IV [CAADID]). All participants also completed the Conners' Adult ADHD Rating Scale (CAARS), which was normed on the general adult population and includes subscales for DSM-IV inattentive and DSM-IV hyperactive-impulsive symptoms. A T-score threshold of 65 (at least 1.5 SD above population mean) on the CAARS DSM-IV hyperactive-impulsive dimension was used to identify participants with empirically elevated symptom severity. Results: Of 88 participating adults, 48 (55%) had a T-score of at least 65 (1.5 SD) on the CAARS DSM-IV Hyperactive-Impulsive scale. Of these, only 25 (52%) met the DSM-IV cutoff of six hyperactive-impulsive symptoms on the CAADID. Thus, approximately half of those who reported empirically elevated hyperactive-impulsive complaints on the CAARS did not concurrently meet the six-symptom DSM-IV cutoff on the CAADID. An alternative cutoff of four hyperactive-impulsive symptoms on the CAADID captured 39 (81%) cases identified by the CAARS. Conclusion: In adults, mandating at least six hyperactive-impulsive symptoms excludes a significant percentage (almost half) of adults who are at least 1.5 SD above the population mean on a dimensional measure of hyperactivity-impulsivity. These data provide a compelling basis for lowering the symptom threshold of hyperactivity-impulsivity for adults in the DSM-5.  相似文献   
286.
Bilingualism: consequences for mind and brain   总被引:1,自引:0,他引:1  
Building on earlier evidence showing a beneficial effect of bilingualism on children's cognitive development, we review recent studies using both behavioral and neuroimaging methods to examine the effects of bilingualism on cognition in adulthood and explore possible mechanisms for these effects. This research shows that bilingualism has a somewhat muted effect in adulthood but a larger role in older age, protecting against cognitive decline, a concept known as 'cognitive reserve'. We discuss recent evidence that bilingualism is associated with a delay in the onset of symptoms of dementia. Cognitive reserve is a crucial research area in the context of an aging population; the possibility that bilingualism contributes to cognitive reserve is therefore of growing importance as populations become increasingly diverse.  相似文献   
287.
Although the study of brain states is an old one in neuroscience, there has been growing interest in brain state specification owing to MRI studies tracing brain connectivity at rest. In this review, we summarize recent research on three relatively well-described brain states: the resting, alert, and meditation states. We explore the neural correlates of maintaining a state or switching between states, and argue that the anterior cingulate cortex and striatum play a critical role in state maintenance, whereas the insula has a major role in switching between states. Brain state may serve as a predictor of performance in a variety of perceptual, memory, and problem solving tasks. Thus, understanding brain states is critical for understanding human performance.  相似文献   
288.
This paper examines the effects of group performance anxiety on the attrition of women and minorities from science, math, and engineering majors. While past research has relied primarily on the academic deficits and lower socioeconomic status of women and minorities to explain their absence from these fields, we focus on the impact of stereotype threat—the anxiety caused by the expectation of being judged based on a negative group stereotype. Using data from the National Longitudinal Survey of Freshmen, our findings indicate that minorities experience stereotype threat more strongly than whites, although women do not suffer from stereotype threat more than men. Our findings also reveal that stereotype threat has a significant positive effect on the likelihood of women, minorities, and surprisingly, white men leaving science, technology, engineering and math majors.  相似文献   
289.
This study aims at illustrating the interest of a methodology of exploration of identity dynamics, the IMIS(Zavalloni & Louis-Guerin, 1984), for the elaboration of the professional project. Psychosocial identity is a system of representations of oneself and the world animated by the paradox of being identical and distinct at the same time. This system justifies ways of thought and action, that are retrieved in identity strategies. Action is presented as a medium-term project, endowed with a function of regulation of identity and capability representations that it conveys and validates(Costalat-Founeau, 2008). The project therefore leans upon the cognitive substrate of experience. Action doesn’t follow the project, both are interwoven in a common perspective defined by intentional objectives(Young & Valach, 2006).  相似文献   
290.
Sustained treatment attendance has been reported to be poor in publicly funded community-based clinic settings serving children and families. Several child and family characteristics have been shown to predict attendance in community-based care, but virtually no research has been conducted to examine how experiences in care, including psychotherapists' within-session practices, influence client attendance. The goal of this exploratory study was to examine how observed practice within sessions, in particular the extent to which therapists delivered elements consistent with evidence-based practices, impacts total number of sessions attended, while accounting for an array of other potential predictors. Participants include 181 children ages 4-13 and their parents entering a new episode of care for disruptive behavior problems in publicly funded clinics. Data sources include administrative billing records on treatment attendance; coded videotaped treatment sessions; and self-reports from children, parents, and therapists. Results indicate that parent education, service funding source, parent alliance with therapist, and therapist experience predicted number of sessions attended; intensity of evidence-based treatment techniques delivered to children was marginally associated with attendance (p = .059). Implications for improving engagement in community-based care are discussed.  相似文献   
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