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931.
This essay is an exploratory study of the uses and gratifications of social networking applications and sites widely utilized by gay men. Based on findings from six different focus groups and intercept interviews with gay and bisexual men, this essay explores the motivations and perceived benefits of social networking sites that allow for the creation of a virtual community of sexual minorities. This paper also considers these technological developments as part of a larger history of gay men communicating with other gay men within a culture where talk about homosexuality is closely policed and often restricted. Through a uses and gratifications approach, this essay discusses the needs and motivations that bring gay men online to social network sites, how they manage multiple identities online and the resulting gratifications of their online activity.  相似文献   
932.
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   
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936.
Disrupting the reactivation of hippocampal neurons during sleep impairs memory consolidation in rats. However, the functional importance of reactivation during awake states is unknown. An experiment in which awake reactivation was disrupted suggests that this phenomenon could adaptively guide behavior by linking previous learning with the current state of the world.  相似文献   
937.
How can we improve learner drivers’ visual skills? Much research has demonstrated that learner drivers have an impoverished spread of search during driving and that this is partly due to lack of knowledge of where and when to look, rather than simply an issue of cognitive load. Several training interventions have tried to improve scanning in these drivers with limited success. We propose that exposing drivers to examples of good and bad scanning behaviour may prove to be a useful tool in training visual search. The success of this approach, however, requires drivers to be able to distinguish between examples of good and bad scanning. To this end, two studies were undertaken where video clips of simulated driving with an overlaid eye movement trace were presented to participants who had to judge whether the eye movements were that of a learner driver or a driving instructor. Overall, participants found this discrimination task very difficult. However, the findings suggested that novice and learner drivers were able to correctly classify those eye movement traces of other learner drivers better than chance. It was also demonstrated that the ability to distinguish between the eye movements of learner drivers and driving instructors improved as the number of objective differences between the two groups increased across specific scenarios (as determined by frame-by-frame analysis using a priori categories). The results suggest that, under certain situations, drivers can extract information about the appropriateness of a particular scanning strategy just by watching a video of the eye movement trace. The implications for training interventions are discussed.  相似文献   
938.
ABSTRACT The purpose of this study was to measure the specificity of the 21-Item Test for detecting malingering in an elderly sample. The 21-Item Test was administered to 20 community-dwelling elderly individuals with means for age, education, and Short Portable Mental Status Questionnaire (SPMSQ) error scores of 76.25 years (SD?=?7.19), 14.30 years (SD?=?3.89), and 0.30 (SD?=?4.70). None of these healthy elderly participants were cognitively impaired. A second group of 53 nursing home residents had means for age, education, and SPMSQ error scores of 82.79 years (SD?=?8.56), 11.14 years (SD = 2.46), and 3.17 (SD?=?2.46). Approximately 60% of the nursing home participants had cognitive impairment based on the SPMSQ. The cut offs provided by Iverson (1998 , 21 Item Test Research Manual) for interpretation of the forced-choice component of the 21-Item Test were insensitive to age and relatively insensitive to cognitive deficits. Specificity was 100% since no elderly participant from either group scored in the range indicative of sub-optimal effort or biased responding.  相似文献   
939.
Conceptions of well-being are defined as a system of beliefs concerning the nature and experience of well-being and can be described generally by the degree to which four dimensions, representing (1) the experience of pleasure, (2) avoidance of negative experience, (3) selfdevelopment, and (4) contribution to others, are emphasized. A first main objective of the current study was to investigate age-related differences in younger and older adults’ conceptions of well-being. A second main objective was to address whether conceptions of well-being are differentially associated with experienced well-being in younger and older adults. Results indicated several age-related differences in conceptions of well-being, with younger adults reporting more emphasis on the experience of pleasure and self-development, older adults reporting more emphasis on avoidance of negative experience, and younger and older adults reporting similar levels of emphasis on contribution to others. Results further indicated several age-related differences in associations between the experience of pleasure and avoidance of negative experience dimensions and well-being, with these two dimensions being more strongly and positively associated with well-being in older adults. Self-development and contribution to others were found to be positively associated with well-being regardless of age.  相似文献   
940.
It has been speculated that cage mesh exerts a shaping influence on reaching behavior by captive apes, which is then misconstrued as pointing by human observers. Although this notion is clearly falsified by the pointing of captive language-trained apes—who point in the absence of intervening cage mesh—nevertheless, the degree to which cage mesh might influence pointing hand shapes by captive great apes in other housing environments remains relatively unexplored. We examined 259 pointing gestures displayed in archival footage from over 18 h of observation by three nonlanguage-trained chimpanzees housed at a biomedical research center. We coded points in relation to how close to the boundaries of the diamond-shaped cage mesh their points were displayed. We found that points with the whole hand were significantly more likely to be displayed away from the mesh boundaries, relative to points with the index finger or other single-digit points. However, points of each hand shape were displayed at each location, demonstrating that these physical parameters do not fully account for the number of fingers extended while pointing by chimpanzees.  相似文献   
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