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161.
It seems likely that an increasing number of young people in the isolated region of Ladakh are experiencing mental problems in relation to the process of acculturation. Ladakh, a Himalayan region situated in the northeast of India, has undergone rapid development. It has been influenced by the opening of the area for tourists in 1974 and from the massive presence of the Indian military. This work explores the discourses among intellectuals, practitioners and young people about psychopathology among the Ladakhi youth in relation to socio-cultural changes. Based on the discourse analysis and a review of relevant theoretical perspectives, it is argued that development is causing a greater diversity in the youth, and that the combination of greater pressure and less cultural support may be causing an increase in psychopathology.  相似文献   
162.
Serial recall is often assumed to involve response suppression: the removal or inhibition of items already recalled so that they are not recalled again. Evidence for response suppression includes repetition inhibition and the separation of erroneous repetitions. Some theorists have suggested that response suppression, by eliminating competing responses, also contributes to recency in forward serial recall. We present experiments in which performance on the final item was examined as a function of whether or not the preceding retrievals entailed suppression of potential response competitors. In line with the predictions of response suppression, recency was found to be reduced when the earlier recall errors consisted of intrusion errors (which leave list items unsuppressed) rather than transposition errors (which involve suppression).  相似文献   
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164.
Externalizing psychopathology (EXT) is a framework for understanding diagnostic comorbidity and etiology of antisocial and substance-use behaviors. EXT indicates continuity in adulthood but the structure of adolescent EXT is less clear. This report examines whether adolescent EXT is trait-like, as has been found with adults, or categorical. We use tests of measurement invariance to determine how diagnostic indicators of EXT differ in adolescents compared to adults. The EXT measures employed were DSM-IIIR diagnoses of adult antisocial behavior, conduct disorder, and alcohol, marijuana, and drug dependence. Latent trait, latent class, and hybrid models were fit to two separate data sets: 2,769 seventeen-year-old adolescents and 2,619 adults from the Minnesota Twin Family Study. The best model in both samples was a single-trait LT model. Parameters from the adolescent and adult models were equivalent for all disorders except alcohol dependence. It appears that EXT in adolescence can be accurately represented by a single-trait model, and the measurement properties of EXT are similar during these time periods with the exception of alcohol dependence.  相似文献   
165.
Tripping and falling is a serious health problem for older citizens due to the high medical costs incurred and the high mortality rates precipitated mostly by hip fractures that do not heal well. Current falls prevention technology encompasses a broad range of interventions; both passive (e.g., safer environments, hip protectors) and active (e.g., sensor-based fall detectors) which attempt to reduce the effects of tripping and falling. However the majority of these interventions minimizes the impact of falls and do not directly reduce the risk of falling. This paper investigates the prediction of gait parameters related to foot-to-ground clearance height during the leg swing phase which have been physically associated with tripping and falling risk in the elderly. The objective is to predict parameters of foot trajectory several walking cycles in advance so that anticipated low foot clearance could be addressed early with more volitional countermeasures, e.g., slowing down or stopping. In this primer study, foot kinematics was recorded with a highly accurate motion capture system for 10 healthy adults (25-32 years) and 11 older adults (65-82 years) with a history of falls who each performed treadmill walking for at least 10 min. Vertical foot displacement during the swing phase has three characteristic inflection points and we used these peak values and their normalized time as the target prediction values. These target variables were paired with features extracted from the corresponding foot acceleration signal (obtained through double differentiation). A generalized regression neural network (GRNN) was used to independently predict the gait variables over a prediction horizon (number of gait cycles ahead) of 1-10 gait cycles. It was found that the GRNN attained 0.32-1.10 cm prediction errors in the peak variables and 2-8% errors in the prediction of normalized peak times, with slightly better accuracies in the healthy group compared to elderly fallers. Prediction accuracy decreased linearly (best fit) at a slow rate with increasing prediction horizon ranging from 0.03 to 0.11 cm per step for peak displacement variables and 0.34 × 10(-3) - 1.81 × 10(-3)% per step for normalized peak time variables. Further time series analysis of the target gait variable revealed high autocorrelations in the faller group indicating the presence of cyclic patterns in elderly walking strategies compared to almost random walking patterns in the healthy group. The results are promising because the technique can be extended to portable sensor-based devices which measure foot accelerations to predict the onset of risky foot clearance, thus leading to a more effective falls prevention technology.  相似文献   
166.
This article celebrates the contribution that the American Journal of Psychology (AJP) has made to the area of perceptual-motor skill over its 125-year history. We highlight the articles published in AJP and trace the technical and theoretical developments that stem from this groundbreaking work. Included in our overview are AJP articles on the excitability of the motor system, motor learning, adaptation to visual rearrangement, the ecological approach to perception and action, and the measurement of human handedness. We conclude by identifying a number of areas associated with perceptual-motor skill where AJP continues to make an important contribution.  相似文献   
167.
168.
Gaze behaviour during space perception and spatial decision making   总被引:1,自引:0,他引:1  
A series of four experiments investigating gaze behavior and decision making in the context of wayfinding is reported. Participants were presented with screenshots of choice points taken in large virtual environments. Each screenshot depicted alternative path options. In Experiment 1, participants had to decide between them to find an object hidden in the environment. In Experiment 2, participants were first informed about which path option to take as if following a guided route. Subsequently, they were presented with the same images in random order and had to indicate which path option they chose during initial exposure. In Experiment 1, we demonstrate (1) that participants have a tendency to choose the path option that featured the longer line of sight, and (2) a robust gaze bias towards the eventually chosen path option. In Experiment 2, systematic differences in gaze behavior towards the alternative path options between encoding and decoding were observed. Based on data from Experiments 1 and 2 and two control experiments ensuring that fixation patterns were specific to the spatial tasks, we develop a tentative model of gaze behavior during wayfinding decision making suggesting that particular attention was paid to image areas depicting changes in the local geometry of the environments such as corners, openings, and occlusions. Together, the results suggest that gaze during a wayfinding tasks is directed toward, and can be predicted by, a subset of environmental features and that gaze bias effects are a general phenomenon of visual decision making.  相似文献   
169.
The role of interpersonal components of perfectionism in suicide outcomes among youth was assessed and the Perfectionism Social Disconnection Model (PSDM) was tested by determining whether the links between socially prescribed perfectionism (SPP) and perfectionistic self-presentation (PSP) and suicide outcomes are mediated by experiences of social disconnection, as indicated by social hopelessness and being bullied. PSP, trait perfectionism, suicide outcomes, and experiences of being bullied and social hopelessness were measured in 152 psychiatric outpatient children and adolescents. Correlational tests confirmed that PSP and SPP were associated with suicide outcomes and these interpersonal perfectionism components were associated significantly with bullying and social hopelessness. Support was also obtained for the PSDM. The relationship between the PSP facets, particularly nondisplay of imperfections, and suicide outcomes were mediated by being bullied. Additionally, the relationship between all interpersonal components of perfectionism and suicide risk was mediated by social hopelessness. Theoretical and clinical implications of interpersonal components of perfectionism and social disconnection in suicide outcomes for youth are discussed.  相似文献   
170.
This paper examines the activities of churches in Baltimore, Maryland, concerning the issues of sexuality, whether they potentially stigmatize persons with or at risk for HIV/AIDS, and to what extent individual agency versus institutional forces influence churches in this regard. In-depth interviews were conducted with 20 leaders from 16 churches and analyzed using a grounded theory methodology. Although many churches were involved in HIV/AIDS-related activities, the content of such initiatives was sometimes limited due to organizational constraints. Church leaders varied, however, in the extent to which they responded in accordance with or resisted these constraints, highlighting the importance of individual agency influencing churches?? responses to HIV/AIDS.  相似文献   
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