Dopamine,depressive symptoms,and decision-making: the relationship between spontaneous eye blink rate and depressive symptoms predicts Iowa Gambling Task performance

Depressive symptomatology has been associated with alterations in decision-making, although conclusions have been mixed, with depressed individuals showing impairments in some contexts but advantages in others. The dopaminergic system may link depressive symptoms with decision-making performance. We assessed the role of striatal dopamine D₂ receptor density, using spontaneous eye blink rates, in moderating the relationship between depressive symptoms and decision-making performance in a large undergraduate sample that had not been screened for mental illness (N?=?104). The regression results revealed that eye blink rate moderated the relationship between depressive symptoms and advantageous decisions on the Iowa Gambling Task, in which individuals with more depressive symptomatology and high blink rates (higher striatal dopamine D₂ receptor density) performed better on the task. Our computational modeling results demonstrated that depressive symptoms alone were associated with enhanced loss-aversive behavior, whereas individuals with high blink rates and elevated depressive symptoms tended to persevere in selecting options that led to net gains (avoiding options with net losses). These findings suggest that variation in striatal dopamine D₂ receptor availability in individuals with depressive symptoms may contribute to differences in decision-making behavior.     

Ostracism Reduces Reliance on Poor Advice from Others during Decision Making

Decision making is rarely context‐free, and often, both social information and non‐social information are weighed into one's decisions. Incorporating information into a decision can be influenced by previous experiences. Ostracism has extensive effects, including taxing cognitive resources and increasing social monitoring. In decision making situations, individuals are often faced with both objective and social information and must choose which information to include or filter out. How will ostracism affect the reliance on objective and social information during decision making? Participants (N = 245) in Experiment 1 were randomly assigned to be included or ostracized in a standardized, group task. They then performed a dynamic decision making task that involved the presentation of either non‐social (i.e. biased reward feedback) or social (i.e., poor advice from a previous participant) misleading information. In Experiment 2, participants (N = 105) completed either the ostracism non‐social condition or social misleading information condition with explicit instructions stating that the advice given was from an individual who did not partake in the group task. Ostracized individuals relied more on non‐social misleading information and performed worse than included individuals. However, ostracized individuals discounted misleading social information and outperformed included individuals. Results of Experiment 2 replicated the findings of Experiment 1. Across two experiments, ostracized individuals were more critical of advice from others, both individuals who may have ostracized them and unrelated individuals. In other words, compared with included individuals, ostracized individuals underweighted advice from another individual but overweighed non‐social information during decision making. We conclude that when deceptive objective information is present, ostracism results in disadvantageous decision making. Copyright © 2015 John Wiley & Sons, Ltd.     

Adult age differences in frontostriatal representation of prediction error but not reward outcome

Emerging evidence from decision neuroscience suggests that although younger and older adults show similar frontostriatal representations of reward magnitude, older adults often show deficits in feedback-driven reinforcement learning. In the present study, healthy adults completed reward-based tasks that did or did not depend on probabilistic learning, while undergoing functional neuroimaging. We observed reductions in the frontostriatal representation of prediction errors during probabilistic learning in older adults. In contrast, we found evidence for stability across adulthood in the representation of reward outcome in a task that did not require learning. Together, the results identify changes across adulthood in the dynamic coding of relational representations of feedback, in spite of preserved reward sensitivity in old age. Overall, the results suggest that the neural representation of prediction error, but not reward outcome, is reduced in old age. These findings reveal a potential dissociation between cognition and motivation with age and identify a potential mechanism for explaining changes in learning-dependent decision making in old adulthood.     

解读曼殊五部曲

苏曼殊是清末民初萃集革命与刨作于一身的“奇人异僧”。从革命的角度说,他意志坚定,积极投身于孙中山领导的资产阶级民主革命,为推翻清朝统治和袁世凯帝制尽心竭力;从创作的角度说,他多才多艺,以风格独特的诗歌、小说、散、翻译、绘画树帜坛,赢得生前和身后无数读的击节和赞赏;从身份的角度说,他是个亦僧亦俗、亦侠亦儒的革命和艺家。他曾获得的桂冠大体停留在不大反映本质的“诗僧”、“情僧”、“风流和尚”、“革命和尚”等一类称号上,然而随着这位传奇的历史人物的“真面目”越来越清晰呈现于世,而不再继续充当人们揣测的对象。     

注重检验专业学生在微生物检验实习中临床沟通能力的培养

临床检验专业已成为独立的学科,微生物检验对临床抗感染合理用药具有指导意义.微生物检验实习生需通过完善知识结构,强化专业技术实践,加强临床合作,积极参与病例讨论,加强师生之间沟通,以及沟通技巧的学习,促进临床沟通能力的培养.