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111.
Daily college drinking data often have highly skewed distributions with many zeroes and a rising and falling pattern of use across the week. Alcohol researchers have typically relied on statistical models with dummy variables for either the weekend or all days of the week to handle weekly patterns of use. However, weekend versus weekday categorizations may be too simplistic and saturated dummy variable models too unwieldy, particularly when covariates of weekly patterns are included. In the present study we evaluate the feasibility of cyclical (sine and cosine) covariates in a multilevel hurdle count model for evaluating daily college alcohol use data. Results showed that the cyclical parameterization provided a more parsimonious approach than multiple dummy variables. The number of drinks when drinking had a smoothly rising and falling pattern that was reasonably approximated by cyclical terms, but a saturated set of dummy variables was a better model for the probability of any drinking. Combining cyclical terms and multilevel hurdle models is a useful addition to the data analyst toolkit when modeling longitudinal drinking with high zero counts. However, drinking patterns were not perfectly sinusoidal in the current application, highlighting the need to consider multiple models and carefully evaluate model fit.  相似文献   
112.
113.
Reinforcement learning (RL) models of decision‐making cannot account for human decisions in the absence of prior reward or punishment. We propose a mechanism for choosing among available options based on goal‐option association strengths, where association strengths between objects represent previously experienced object proximity. The proposed mechanism, Goal‐Proximity Decision‐making (GPD), is implemented within the ACT‐R cognitive framework. GPD is found to be more efficient than RL in three maze‐navigation simulations. GPD advantages over RL seem to grow as task difficulty is increased. An experiment is presented where participants are asked to make choices in the absence of prior reward. GPD captures human performance in this experiment better than RL.  相似文献   
114.
Little is known about how family functioning relates to psychosocial functioning of youth with inflammatory bowel disease (IBD). The study aim was to examine family problem solving and affective involvement as moderators between adolescent disease severity and depressive symptoms. Participants were 122 adolescents with IBD and their parents. Measures included self-reported and parent-reported adolescent depressive symptoms, parent-reported family functioning, and physician-completed measures of disease severity. Disease severity was a significant predictor of adolescent-reported depressive symptoms, but not parent-reported adolescent depressive symptoms. Family affective involvement significantly predicted parent-reported adolescent depressive symptoms, while family problem-solving significantly predicted adolescent self-report of depressive symptoms. Neither affective involvement nor problem-solving served as moderators. Family affective involvement may play an important role in adolescent emotional functioning but may not moderate the effect of disease severity on depressive symptoms. Research should continue to examine effects of family functioning on youth emotional functioning and include a sample with a wider range of disease severity to determine if interventions aimed to enhance family functioning are warranted.  相似文献   
115.
Elucidating the neural basis of joint attention in infancy promises to yield important insights into the development of language and social cognition, and directly informs developmental models of autism. We describe a new method for evaluating responding to joint attention performance in infancy that highlights the 9‐ to 10‐month period as a time interval of maximal individual differences. We then demonstrate that fractional anisotropy in the right uncinate fasciculus, a white matter fiber bundle connecting the amygdala to the ventral‐medial prefrontal cortex and anterior temporal pole, measured in 6‐month‐olds predicts individual differences in responding to joint attention at 9 months of age. The white matter microstructure of the right uncinate was not related to receptive language ability at 9 months. These findings suggest that the development of core nonverbal social communication skills in infancy is largely supported by preceding developments within right lateralized frontotemporal brain systems.  相似文献   
116.
ABSTRACT

We investigated the feasibility of using the Space Fortress (SF) game, a complex video game originally developed to study complex skill acquisition in young adults, to improve executive control processes in cognitively healthy older adults. The study protocol consisted of 36 one-hour game play sessions over 3 months with cognitive evaluations before and after, and a follow-up evaluation at 6 months. Sixty participants were randomized to one of three conditions: Emphasis Change (EC) – elders were instructed to concentrate on playing the entire game but place particular emphasis on a specific aspect of game play in each particular game; Active Control (AC) – game play with standard instructions; Passive Control (PC) – evaluation sessions without game play. Primary outcome measures were obtained from five tasks, presumably tapping executive control processes. A total of 54 older adults completed the study protocol. One measure of executive control, WAIS-III letter–number sequencing, showed improvement in performance from pre- to post-evaluations in the EC condition, but not in the other two conditions. These initial findings are modest but encouraging. Future SF interventions need to carefully consider increasing the duration and or the intensity of the intervention by providing at-home game training, reducing the motor demands of the game, and selecting appropriate outcome measures.  相似文献   
117.
This research examines the relationship between family structure and subjective well-being and the extent to which cultural differences across 24 countries/regions may condition that relationship. Using the 2002 ISSP data, we examine how the effects of marriage status and the presence of children on happiness and satisfaction with family life differ according to the perceived importance of marriage and parenthood in society. We find significant cross-country differences in the relationship between presence of young children and the happiness of men, and in the relationship between the marital status of women and their happiness and satisfaction with family life.  相似文献   
118.
It has been found that university students who were the least skilled at managing their emotions also had the lowest intention of seeking help from a variety of nonprofessional sources (e.g. family and friends). The present study sought to extend these findings by focusing on adolescents, examining a larger number of emotional competencies, and exploring the possibility that social support explains the relationship between emotional competence and help-seeking. A total of 137 adolescents (aged 16-18) completed an anonymous survey that assessed social support, emotional competencies, and intention to seek help from a variety of professional and nonprofessional sources. As expected, adolescents who were low in emotional awareness, and who were poor at identifying, describing, and managing their emotions, were the least likely to seek help from nonprofessional sources and had the highest intention of refusing help from everyone. However, low emotional competence was not related to intention to seek help from professional sources (e.g. mental health professionals). The significant results involving nonprofessional sources were only partially explained by social support, suggesting that even adolescents who had high quality support were less likely to make use of that support if they were low in emotional competence.  相似文献   
119.
Mandated supervision with disciplined mental health professionals is defined and discussed. In the absence of empirical support for supervision in this context, sources of theoretical support are provided. Risks, benefits, and implications for practice for supervisors are also discussed.  相似文献   
120.
Neuropsychological data are reviewed from two sets of dizygotic twins presenting with selective mutism characterized by situation specific anxiety, extreme passive behavior, lack of responsivity, lack of peer interaction, and a chronic course of selective mutism. Both sets of twins had a history of prematurity and delayed speech development. One set of twins presented with normal intelligence and normal receptive language skills but with expressive language and oral motor sequencing difficulties. The second set of twins presented with Verbal IQ deficits and significant receptive and expressive language deficits. A summary of current conceptualizations regarding etiology and treatment of selective mutism is provided.  相似文献   
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