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241.
Deliberate self-harm (DSH) is a strong predictor of suicide in schizophrenia. The aim of this review was to identify risk factors for DSH in schizophrenia. This systematic review of the international literature examined cohort and case-control studies of patients with schizophrenia or related diagnoses that reported DSH as an outcome. Studies were identified by searching electronic databases and reference lists, and by consulting international experts. Fourteen studies met the eligibility criteria. Of the 29 variables examined by two or more studies, five (past or recent suicidal ideation, previous DSH, past depressive episode, drug abuse or dependence, and higher mean number of psychiatric admissions) were associated with an increased risk of DSH, and one (unemployment) was associated with a reduced risk. Schizophrenic patients with these risk factors need careful follow-up and monitoring, with treatment of any associated comorbid depression or drug abuse. Large, prospective studies of DSH in schizophrenia are needed to further define risk factors and to build on the findings of this review.  相似文献   
242.
The corpus callosum is the major neural pathway that connects homologous cortical areas of the two cerebral hemispheres. The nature of how that interhemispheric connection is manifested is the topic of this review; specifically, does the corpus callosum serve to communicate an inhibitory or excitatory influence on the contralateral hemisphere? Several studies take the position that the corpus callosum provides the pathway through which a hemisphere or cortical area can inhibit the other hemisphere or homologous cortical area in order to facilitate optimal functional capacity. Other studies suggest that the corpus callosum integrates information across cerebral hemispheres and thus serves an excitatory function in interhemispheric communication. This review examines these two contrasting theories of interhemispheric communication. Studies of callosotomies, callosal agenesis, language disorders, theories of lateralization and hemispheric asymmetry, and comparative research are critically considered. The available research, no matter how limited, primarily supports the notion that the corpus callosum serves a predominantly excitatory function. There is evidence, however, to support both theories and the possibility remains that the corpus callosum can serve both an inhibitory and excitatory influence on the contralateral hemisphere.  相似文献   
243.
The present study examined the relationship between the predictability of words within a sentence and the availability of parafoveal word length information, on when and where the eyes move in reading. Predictability influenced first-pass reading times when parafoveal word length preview information was correct, but not when it was incorrect. Similarly, for saccades launched from near the target word (wordn), predictability influenced the probability with which it was skipped only when the word length preview was correct. By contrast, for saccades launched farther away from wordn, predictability influenced word skipping regardless of the parafoveal word length preview. Taken together, the data suggest that parafoveal word length preview and predictability can act as a joint constraint on the decision of when and where to move the eyes.  相似文献   
244.
Although ADHD and depression are common comorbidities in youth, few studies have examined this particular clinical presentation. To address method bias limitations of previous research, this study uses multiple informants to compare the academic, social, and clinical functioning of children with ADHD, children with ADHD and depression, and children without ADHD, all derived from a large community sample. High levels of comorbid depression are found in children with ADHD. Children withADHDand depression are more depressed and anxious than their non-depressed ADHDcounterparts but do not have more extreme levels of ADHD or aggression. The association between depression and ADHD does not appear to be epiphenomenal, that is, related to a shared association with anxiety or externalizing symptoms. Finally, children with ADHD and depression display more impairment in social and academic functioning compared to controls. Although social impairment is greater in children with ADHD and depression than in children with only ADHD, conduct problems are not.  相似文献   
245.
The concept of Internet addiction has been proposed as an explanation for uncontrollable and damaging use of the Internet. Symptoms of excessive Internet use have been compared to the criteria used to diagnose other addictions such as pathological gambling. Although criteria to diagnose this problem have been proposed, methods of assessing excessive Internet use are limited. A structured interview based on the criteria proposed by Beard and Wolf is proposed to aid in the assessment of "Internet addiction." This, in turn, could aid in the diagnosis and intervention of a client who enters treatment reporting difficulties with excessive Internet use.  相似文献   
246.
247.
Tracking multiple targets with multifocal attention   总被引:8,自引:0,他引:8  
Attention allows us to monitor objects or regions of visual space and select information from them for report or storage. Classical theories of attention assumed a single focus of selection but many everyday activities, such as video games, navigating busy intersections, or watching over children at a swimming pool, require attention to multiple regions of interest. Laboratory tracking tasks have indeed demonstrated the ability to track four or more targets simultaneously. Although the mechanisms by which attention maintains contact with several targets are not yet established, recent studies have identified several characteristics of the tracking process, including properties defining a 'trackable' target, the maximum number of targets that can be tracked, and the hemifield independence of the tracking process. This research also has implications for computer vision, where there is a growing demand for multiple-object tracking.  相似文献   
248.
Semantic features have provided insight into numerous behavioral phenomena concerning concepts, categorization, and semantic memory in adults, children, and neuropsychological populations. Numerous theories and models in these areas are based on representations and computations involving semantic features. Consequently, empirically derived semantic feature production norms have played, and continue to play, a highly useful role in these domains. This article describes a set of feature norms collected from approximately 725 participants for 541 living (dog) and nonliving (chair) basic-level concepts, the largest such set of norms developed to date. This article describes the norms and numerous statistics associated with them. Our aim is to make these norms available to facilitate other research, while obviating the need to repeat the labor-intensive methods involved in collecting and analyzing such norms. The full set of norms may be downloaded from www.psychonomic.org/archive.  相似文献   
249.
A random sample of hospital administrators throughout the United States was surveyed about their views on the importance of eleven chaplain roles and functions. The 494 respondents fell into three categories: (1) directors of pastoral care departments (N = 132); (2) administrators of hospitals that have a pastoral care department (N = 180); and (3) administrators of hospitals that do not have a pastoral care department (N = 182). All three groups considered all eleven roles to be relatively important, although administrators of hospitals that do not have a pastoral care department gave lower ratings, overall. Meeting the emotional needs of patients and relatives were seen as chaplains most important roles, whereas performing religious rituals and conducting religious services were seen as least important by all three groups. In all but a few instances, the level of importance that administrators assigned to the various roles were positively related to their ratings of their own religiousness and spirituality (r's = .11 to .26, p < .05).  相似文献   
250.
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