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891.
This study examined whether a briefly presented target was mislocalized toward a subjective contour. Observers manually reproduced the position of a briefly presented peripheral target circle above a central fixation cross. A luminance contour, a subjective contour, or a no-contour stimulus was presented in either the left of right visual field, and a no-contour control was presented in the opposite visual field. After these stimuli vanished, a target circle was then presented. Consequently, the degree of mislocalization toward the subjective and luminance contours was the same; this indicated that image integration at a coarse spatial scale cannot explain mislocalization. Experiment 2 revealed that the mislocalization in Experiment 1 was not a result of eye movements. Experiment 3 found that the spatial attention allocated at the location of the luminance and subjective contours was more than that allocated at the no-contour stimulus. An attentional shift toward the task-irrelevant stimulus resulted in a mislocalization of the target.  相似文献   
892.
The aim of the present fMRI study was to localize brain areas that were uniquely activated for phonological versus spatial working memory. Previous studies have reported inconsistent results, most likely because of methodological heterogeneity varying both stimuli and instructions in the same study. Here, identical consonant-vowel-consonant non-words were visually presented to the subjects in a 2-back paradigm under two different instructions; the subjects either had to memorize the non-words per se or their location. The results give evidence for a hemispheric organization of working memory, with dominance for processing of phonological information in the left hemisphere and frontal cortex, and spatial information in the right hemisphere and parietal cortex. The results also reflect a certain overlap between the neuronal network for working memory and processing of verbal and spatial material. These findings are discussed with regard to processing specificity and the extent that activated areas also may reflect perceptual processes.  相似文献   
893.
This study examined the relationship between PMS and emotion-related electromyographic facial activity at different phases of the menstrual cycle. Twenty-four women of reproductive age (12 with PMS, 12 controls) participated in two EMG sessions (T1 and T2) in which they were shown photographic images that can elicit various emotions (IAPS stimuli). T1 took place in the follicular phase, T2 in the luteal phase. The activity of the musculus depressor anguli oris ("depressor", expression of sadness) was measured. Depressor activity was compared to activity of musculus orbicularis oculi ("orbicularis"; expression of joy). ANOVA yielded a significant increase of the activity of the depressor at T2 in the PMS group. The PMS group showed more frequent depressor activity during the luteal than the follicular phase. Orbicularis activity did not change from T1 to T2. Conclusions: The PMS group experienced various visual stimuli in a more depressed way during the luteal phase.  相似文献   
894.
Verbal fluency tests are useful measures of acquired language impairment and cognitive decline of various etiologies. The aim of this study was to provide normative data for the Swedish population on the three verbal fluency tests, FAS, Animals and Verbs. A group of 165 healthy participants ranging from 16 to 89 years of age were assessed with the verbal fluency tests and tests of level of intellectual functioning. The sample was stratified by education, age and gender. Level of education had a substantial influence on the performance on verbal fluency, most clearly so in FAS and Verbs. Intellectual level had a positive and significant correlation with all measures of word fluency. Moreover, there was an interaction between age and gender such that women aged between 30 and 64 years outperformed elderly men on FAS and Verbs. Guidelines for instructions and scoring in Swedish are given in the article.  相似文献   
895.
This article illustrates ideas for bridging science and practice generated during the Division of Violence Prevention's (DVP) dissemination/implementation planning process. The difficulty of moving what is known about what works into broader use is near universal, and this planning process pushed us to look beyond the common explanations (e.g., providers were resistant/unwilling to change practice) and think about the multiple layers and systems involved. As part of this planning process, the Interactive Systems Framework for Dissemination and Implementation (ISF) was developed and then applied to the fields of child maltreatment and youth violence prevention. Challenges for each of the three systems in the ISF are discussed as well as and action and research ideas to address the challenges. Also described are actions taken by DVP in response to the planning process to illustrate how a funder can use the ISF to bridge science and practice.  相似文献   
896.
This experiment compared the effectiveness of an unlocked, mental health consumer-managed, crisis residential program (CRP) to a locked, inpatient psychiatric facility (LIPF) for adults civilly committed for severe psychiatric problems. Following screening and informed consent, participants (n = 393) were randomized to the CRP or the LIPF and interviewed at baseline and at 30-day, 6-month, and 1-year post admission. Outcomes were costs, level of functioning, psychiatric symptoms, self-esteem, enrichment, and service satisfaction. Treatment outcomes were compared using hierarchical linear models. Participants in the CRP experienced significantly greater improvement on interviewer-rated and self-reported psychopathology than did participants in the LIPF condition; service satisfaction was dramatically higher in the CRP condition. CRP-style facilities are a viable alternative to psychiatric hospitalization for many individuals facing civil commitment.  相似文献   
897.
Working memory is one of several putative core neurocognitive processes in attention-deficit/hyperactivity disorder (ADHD). The present work seeks to determine whether visual–spatial working memory is sensitive to motivational incentives, a laboratory analogue of behavioral treatment. Participants were 21 children (ages 7–10) with a diagnosis of ADHD-combined type. Participants completed a computerized spatial span task designed to assess storage of visual–spatial information (forward span) and manipulation of the stored information (backward span). The spatial span task was completed twice on the same day, once with a performance-based incentive (trial-wise feedback and points redeemable for prizes) and once without incentives. Participants performed significantly better on the backward span when rewarded for correct responses, compared to the no incentive condition. However, incentives had no effect on performance during the forward span. These findings may suggest the use of motivational incentives improved manipulation, but not storage, of visual–spatial information among children with ADHD. Possible explanations for the differential incentive effects are discussed, including the possibility that incentives prevented a vigilance decrement as task difficulty and time on task increased.  相似文献   
898.
Although materials informing parents about children’s mental health (CMH) problems can improve outcomes, we know relatively little about the design factors that might influence their utilization of available resources. We used a discrete choice conjoint experiment to model the information preferences of parents seeking mental health services for 6 to 18 year olds. Parents completed 30 choice tasks presenting experimentally varied combinations of 20 four-level CMH information content, transfer process, and outcome attributes. Latent class analysis revealed three segments with different preferences. Parents in the Action segment (43%) chose materials providing step-by-step solutions to behavioral or emotional problems. They preferred weekly meetings with other parents and coaching calls from a therapist. The Information segment (41%) chose materials helping them understand rather than solve their child’s problems. These parents were more sensitive to logistical factors such as receiving information in groups, the location where information was available, the modality in which the information was presented, and the time required to obtain and use the information. The Overwhelmed segment (16%) reported more oppositional and conduct problems, felt their children’s difficulties exerted a greater adverse impact on family functioning, and reported higher personal depression scores than those in the Action or Information segments. Nonetheless, they did not choose information about, or solutions to, the problems their children presented. Simulations predicted that maximizing utilization and realizing the potential benefits of CMH information would require knowledge transfer strategies consistent with each segment’s preferences.
Charles E. CunninghamEmail:
  相似文献   
899.
Data from lesion studies suggest that the ability to perceive speech sounds, as measured by auditory comprehension tasks, is supported by temporal lobe systems in both the left and right hemisphere. For example, patients with left temporal lobe damage and auditory comprehension deficits (i.e., Wernicke's aphasics), nonetheless comprehend isolated words better than one would expect if their speech perception system had been largely destroyed (70-80% accuracy). Further, when comprehension fails in such patients their errors are more often semantically-based, than-phonemically based. The question addressed by the present study is whether this ability of the right hemisphere to process speech sounds is a result of plastic reorganization following chronic left hemisphere damage, or whether the ability exists in undamaged language systems. We sought to test these possibilities by studying auditory comprehension in acute left versus right hemisphere deactivation during Wada procedures. A series of 20 patients undergoing clinically indicated Wada procedures were asked to listen to an auditorily presented stimulus word, and then point to its matching picture on a card that contained the target picture, a semantic foil, a phonemic foil, and an unrelated foil. This task was performed under three conditions, baseline, during left carotid injection of sodium amytal, and during right carotid injection of sodium amytal. Overall, left hemisphere injection led to a significantly higher error rate than right hemisphere injection. However, consistent with lesion work, the majority (75%) of these errors were semantic in nature. These findings suggest that auditory comprehension deficits are predominantly semantic in nature, even following acute left hemisphere disruption. This, in turn, supports the hypothesis that the right hemisphere is capable of speech sound processing in the intact brain.  相似文献   
900.
In decision situations of everyday life, the potential positive or negative consequences of a decision are often specified and the associated probabilities are known or they are principally calculable ("decisions under risk"). On the basis of correlations reported in patient studies, it has been recently proposed that decisions under risk involve strategic components, i.e. calculation of the risk, as well as emotional processes, i.e. processing feedback from previous decisions. However, the potential impact of calculative strategies on decision-making under risk has not been investigated systematically, so far. In the current study, we examined 42 healthy subjects (21 females) with the Game of Dice Task measuring decisions under risk, and a questionnaire assessing strategy application in items comparable to the choices in the Game of Dice Task. In addition, the subjects performed the Iowa Gambling Task, examining decision-making under ambiguity, and a neuropsychological test battery focusing on executive functions. Results indicate that deciding advantageously in a decision-making task with explicit and stable rules is linked to applying calculative strategies. In contrast, individuals who decide intuitively prefer risky or disadvantageous choices in the Game of Dice Task. Applying calculative strategies was correlated with executive functions but not with performance on the Iowa Gambling Task. The results support the view that calculative processes and strategies may improve decision-making under explicit risk conditions.  相似文献   
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