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991.
Individuals infected with human immunodeficiency virus (HIV) are at elevated risk for depressive conditions, which in turn can negatively impact health-related behaviours and the course of illness. The present study tested the role of autobiographical memory specificity and its interaction with perceived stress in the persistence of depressive symptoms among dysphoric HIV-positive individuals. Additionally, we examined whether rumination and social problem solving mediated these effects. Results indicated that memory specificity moderated the impact of perceived stress, such that perceived stress was more strongly associated with follow-up depressive symptoms among those with greater memory specificity. Rumination, but not social problem solving, mediated this effect. Implications of these findings are discussed.  相似文献   
992.
The purpose of the current experiment was to distinguish between the impact of strategic and affective forms of gain- and loss-related motivational states on the attention to negative stimuli. On the basis of the counter-regulation principle and regulatory focus theory, we predicted that individuals would attend more to negative than to neutral stimuli in a prevention focus and when experiencing challenge, but not in a promotion focus and under threat. In one experiment (N = 88) promotion, prevention, threat, or challenge states were activated through a memory task, and a subsequent dot probe task was administered. As predicted, those in the prevention focus and challenge conditions had an attentional bias towards negative words, but those in promotion and threat conditions did not. These findings provide support for the idea that strategic mindsets (e.g., regulatory focus) and hot emotional states (e.g., threat vs. challenge) differently affect the processing of affective stimuli.  相似文献   
993.
We sought to determine whether different social, psychological, emotional, and physiological experiences associated with quitting smoking related to people's satisfaction with cessation systematically, and whether the strength of the relations changes at different points during the cessation process and for different people (e.g., optimists). Using data from smokers enrolled in a cessation program, we used mixed models to assess the average longitudinal relation between people's experiences and satisfaction measured at seven time points and whether the relations were moderated by key variables. Eight of nine experiences were related to people's satisfaction (ps < 0.05) and the models accounted for 39–44% of the within-person variance in satisfaction. Current smoking behavior was more strongly related to people's satisfaction during their early efforts to quit, whereas some experiences (e.g., feedback from others) had a stronger relation with satisfaction during people's later efforts to quit or maintain abstinence (ps < 0.05). Individual differences in optimism and prior cessation experience moderated some of the relations (ps < 0.05). The findings mark the first evidence of factors that might influence how people determine their satisfaction with smoking cessation. The implications for tailoring interventions and potentially increasing the likelihood that people maintain abstinence are discussed.  相似文献   
994.
Many immoral acts are the result of gradually escalating behaviors. The present work focuses on observers of immoral acts and the role of continuous commitments in shaping their perceptions of another person's guilt. Across four studies investigating how gradual escalations affect moral judgments, participants read a scenario describing an instance of immoral behavior that gradually built in severity. In Study 1, female participants perceived a perpetrator as less guilty when his behavior gradually escalated to rape after explicitly committing to the appropriateness his initial morally ambiguous behavior. The findings from Study 2 suggest that inducing a categorical mindset can counteract this reduction in perceptions of guilt. Study 3 illustrated the power of the categorical versus continuous mindset by examining how a categorical (versus a continuous mindset) impacts perceptions of guilt even in the absence of gradually escalating behavior. Finally, Study 4 extended the findings from the prior studies to a sample of both men and women and investigated the effect of the mindset manipulation on perceptions. Together, these studies demonstrate that the potency of gradual escalations to induce acquiescence to immoral behavior may inhere in their ability to create initial commitments to and continuous perceptions of morally ambiguous behavior.  相似文献   
995.
We evaluated the reliability and validity of the Dyadic Observed Communication Scale (DOCS) coding scheme, which was developed to capture a range of communication components between parents and adolescents. Adolescents and their caregivers were recruited from mental health facilities for participation in a large, multi-site family-based HIV prevention intervention study. Seventy-one dyads were randomly selected from the larger study sample and coded using the DOCS at baseline. Preliminary validity and reliability of the DOCS was examined using various methods, such as comparing results to self-report measures and examining interrater reliability. Results suggest that the DOCS is a reliable and valid measure of observed communication among parent-adolescent dyads that captures both verbal and nonverbal communication behaviors that are typical intervention targets. The DOCS is a viable coding scheme for use by researchers and clinicians examining parent-adolescent communication. Coders can be trained to reliably capture individual and dyadic components of communication for parents and adolescents and this complex information can be obtained relatively quickly.  相似文献   
996.
Decisions can be made by applying a variety of decision-making rules-sequential rules in which decisions are based on a sequential evaluation of choice dimensions and the integrative normative rule in which decisions are based on an integration of choice dimensions. In this study, we investigated the developmental trajectory of such decision-making rules. In the Gambling Machine Task, participants choose between options that differ in three dimensions: frequency of loss, amount of loss, and certain gain. The task was administered to 231 children and adolescents (age range=8-17 years). Latent group analysis of their performance allowed precise classification of the underlying decision rules. The majority of participants used sequential decision rules, and the number of evaluated dimensions in these rules increased with age. Integrative rule use decreased with age. We discuss these results in light of traditional developmental theories and fuzzy trace theory.  相似文献   
997.
998.
The Fear Survey Schedule for Children-Revised (Ollendick, 1983) is an 80-item self-report instrument that has been used internationally to asses the number of fears and general level of fearfulness among children. Despite its widespread use, this instrument has not been adapted to the South African context. The present study addressed this gap by means of a 2-phase investigation aimed at developing a South African version of the instrument. In Phase 1, semistructured interviews were conducted with 40 children (7 to 13 years of age). Qualitative data obtained from these interviews were used to construct additional items for inclusion in the South African Fear Survey Schedule for Children-Revised. The modified scale, consisting of 97 items, was then administered to a sample of 646 children between the ages of 7 and 13 years. Further psychometric considerations resulted in the final version of the scale consisting of 74 items with high internal consistency (α=.97). The factor structure was explored by means of principal component analysis with varimax rotation and a 5-factor solution was found to provide the best conceptual fit. The factors identified were as follows: Fear of Death and Danger; Fear of the Unknown; Fear of Small Animals and Minor Threats to Self; Large Animal Fears; and Situational Fears. Differences between the South African version and the original Fear Survey Schedule for Children-Revised are noted and implications for the study of fear in South Africa and other countries are discussed.  相似文献   
999.
Arcimboldo images induce the perception of faces when shown upright despite the fact that only nonfacial objects such as vegetables and fruits are painted. In the current study, we examined whether infants recognize a face in the Arcimboldo images by using the preferential looking technique and near-infrared spectroscopy (NIRS). In the first experiment, we measured looking preference between upright and inverted Arcimboldo images among 5- and 6-month-olds and 7- and 8-month-olds. We hypothesized that if infants perceive the Arcimboldo images as faces, they would prefer the upright images to the inverted ones. We found that only 7- and 8-month-olds significantly preferred upright images, suggesting that they could perceive the Arcimboldo images as faces. In the second experiment, we measured hemodynamic responses using NIRS. Based on the behavioral data, we hypothesized that 7- and 8-month-olds would show different neural activity for upright and inverted Arcimboldo images, as do adults. Therefore, we measured hemodynamic responses in 7- and 8-month-olds while they were looking at upright and inverted Arcimboldo images. Their responses were then compared with the baseline activation during the presentation of individual vegetables. We found that the concentration of oxyhemoglobin increased in the left temporal area during the presentation of the upright images compared with the baseline during the presentation of vegetables. The results of the two experiments suggest that (a) the ability to recognize the upright Arcimboldo images as faces develops at around 7 or 8 months of age and (b) processing of the upright Arcimboldo images is related to the left temporal area of the brain.  相似文献   
1000.
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   
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