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161.
This paper reviews the international scientific evidence on the effectiveness of secondary prevention interventions for young drug users. The review provides insight into the effectiveness of interventions that have been evaluated using moderately strong research designs. Most of the studies included are from the United States of America. Some interventions are effective in reducing drug use and associated problems while others have no or mixed effect. Those successful in reducing drug use include behavior therapy, Minnesota 12-step programs, residential care, and general drug treatment. Those with either no effect or mixed effect include schools interventions. Involving parents and other agencies may enhance an intervention's effect. There is a lack of good quality studies outside the USA. Future interventions should focus on either low- or high-risk groups of young drug users. Future research should be conducted on a wider range of services for young people and include non-medical outcomes such as communication skills, schooling, employment, family relations, and economic costs. 相似文献
162.
Much current psychopathology research is framed by categorical constructs. Limitations of categorical constructs have been articulated, and dimensional constructs are often proposed as viable alternatives to categories of psychopathology. The purpose of this Special Section is to articulate and discuss diverse issues that arise in contemplating dimensional constructs as targets for psychopathology research. 相似文献
163.
In four experiments, we investigated the influence of timbre on perceived interval size. In Experiment 1, musically untrained participants heard two successive tones and rated the pitch distance between them. Tones were separated by six or seven semitones and varied in timbre. Pitch changes were accompanied by a congruent timbre change (e.g., ascending interval involving a shift from a dull to a bright timbre), an incongruent timbre change (e.g., ascending interval involving a shift from a bright to a dull timbre), or no timbre change. Ratings of interval size were strongly influenced by timbre. The six-semitone interval with a congruent timbre change was perceived to be larger than the seven-semitone interval with an incongruent timbre change (interval illusion). Experiment 2 revealed similar effects for musically trained participants. In Experiment 3, participants compared the size of two intervals presented one after the other. Effects of timbre were again observed, including evidence of an interval illusion. Experiment 4 confirmed that timbre manipulations did not distort the perceived pitch of tones. Changes in timbre can expand or contract the perceived size of intervals without distorting individual pitches. We discuss processes underlying interval size perception and their relation to pitch perception mechanisms. 相似文献
164.
We carried out three experiments to examine the influence of field of view and binocular viewing restrictions on absolute distance perception in real-world indoor environments. Few of the classical visual cues provide direct information for accurate absolute distance judgments to points in the environment beyond about 2 m from the viewer. Nevertheless, in previous work it has been found that visually directed walking tasks reveal accurate distance estimations in full-cue real-world environments to distances up to 20 m. In contrast, the same tasks in virtual environments produced with head-mounted displays (HMDs) show large compression of distance. Field of view and binocular viewing are common limitations in research with HMDs, and have been rarely studied under full pictorial-cue conditions in the context of distance perception in the real-world. Experiment 1 showed that the view of one's body and feet on the floor was not necessary for accurate distance perception. In experiment 2 we manipulated the horizontal and the vertical field of view along with head rotation and found that a restricted field of view did not affect the accuracy of distance estimations when head movement was allowed. Experiment 3 showed that performance with monocular viewing was equal to that with binocular viewing. These results have implications for the information needed to scale egocentric distance in the real-world and reduce the support for the hypothesis that a limited field of view or imperfections in binocular image presentation are the cause of the underestimation seen with HMDs. 相似文献
165.
The "tip of the fingers" phenomenon (TOF) for sign language parallels the "tip of the tongue" phenomenon (TOT) for spoken language. During a TOF, signers are sure they know a sign but cannot retrieve it. Although some theories collapse semantics and phonology in sign language and thus predict that TOFs should not occur, TOFs were elicited in the current study. Like TOTs, TOFs often resolve spontaneously, commonly involve targets that are proper names, and frequently include partial access to phonology. Specifically, signers were more likely to retrieve a target sign's handshape, location, and orientation than to retrieve its movement. Signers also frequently recalled the first letter of a finger-spelled word. The existence of TOFs supports two-stage retrieval and a division between semantics and phonology in American Sign Language. The partial phonological information available during TOFs suggests that phonological features are accessed more simultaneously during lexical access for signed language than during lexical access for spoken language. 相似文献
166.
Conceptual overlap and heterogeneity have long been noted as weaknesses of the Minnesota Multiphasic Personality Inventory's clinical scales. Restructured clinical (RC) scales recently were developed to address these concerns (A. Tellegen et al., 2003). The authors evaluated the psychometric properties of the RC scales in psychology clinic clients (N=285) and military veterans (N=567). The RC scales were as internally consistent as the clinical scales and correlated strongly with their original counterparts (except for RC3/Hysteria). They also were less intercorrelated, produced conceptually clearer relations with measures of personality and psychopathology, and yielded somewhat greater incremental utility than the clinical scales. Thus, the RC scales demonstrated several psychometric strengths while utilizing 60% fewer items, but the 2 sets of scales cannot be used interchangeably. Interpretive considerations are discussed. 相似文献
167.
Although hypochondriasis is associated with the costly use of unnecessary medical resources, this mental health problem remains largely neglected. A lack of clear conceptual models and valid measures has impeded accurate assessment and hindered progress. The Multidimensional Inventory of Hypochondriacal Traits (MIHT) addresses these deficiencies with scales that correspond to a 4-factor model. The MIHT was built with construct validity as a guiding principle and began with an item pool that broadly assessed dimensions identified in the literature. The items were administered to large samples; factor analyses of the responses led to item pool revisions and scale refinements. Multiple studies validated the final MIHT scales and 4-factor model; these findings suggest that the MIHT will contribute to theory and research. 相似文献
168.
Axilbund JE Hamby LA Thompson DB Olsen SJ Griffin CA 《Journal of genetic counseling》2005,14(3):235-243
Cancer genetic counselors use a variety of teaching modalities for patient education. This survey of cancer genetic counselors assessed their use of educational videos and their recommendations for content of future videos. Thirty percent of respondents use videos for patient education. Cited benefits included reinforcement of information for clients and increased counselor efficiency. Of the 70% who do not use videos, predominant barriers included the perceived lack of an appropriate video, lack of space and/or equipment, and concern that videos are impersonal. Most respondents desired a video that is representative of the genetic counseling session, but emphasized the importance of using broad information. Content considered critical included the pros and cons of genetic testing, associated psychosocial implications, and genetic discrimination. The results of this exploratory study provide data relevant for the development of a cancer genetics video for patient education, and suggestions are made based on aspects of information processing and communication theories. 相似文献
169.
Assessment and treatment of acute responses to traumatic stress has received much attention since September 11, 2001. This article elucidates principles of early intervention with adults in the immediate (within 48 hours) and early recovery phase (within the first week). The principles have been drawn from research on risk and recover factors, stress and traumatic stress theory, and expert consensus recommendations. The debriefing model is discussed, and principle interventions of psychological first aid, pharmacology, and mass trauma systems are described. This article concludes with brief guidelines for longer-term interventions and recommendations for future research. 相似文献
170.
Von Economo neurons (VENs) are a recently evolved cell type which may be involved in the fast intuitive assessment of complex situations. As such, they could be part of the circuitry supporting human social networks. We propose that the VENs relay an output of fronto-insular and anterior cingulate cortex to the parts of frontal and temporal cortex associated with theory-of-mind, where fast intuitions are melded with slower, deliberative judgments. The VENs emerge mainly after birth and increase in number until age 4 yrs. We propose that in autism spectrum disorders the VENs fail to develop normally, and that this failure might be partially responsible for the associated social disabilities that result from faulty intuition. 相似文献