State-based versus reward-based motivation in younger and older adults

Recent decision-making work has focused on a distinction between a habitual, model-free neural system that is motivated toward actions that lead directly to reward and a more computationally demanding goal-directed, model-based system that is motivated toward actions that improve one’s future state. In this article, we examine how aging affects motivation toward reward-based versus state-based decision making. Participants performed tasks in which one type of option provided larger immediate rewards but the alternative type of option led to larger rewards on future trials, or improvements in state. We predicted that older adults would show a reduced preference for choices that led to improvements in state and a greater preference for choices that maximized immediate reward. We also predicted that fits from a hybrid reinforcement-learning model would indicate greater model-based strategy use in younger than in older adults. In line with these predictions, older adults selected the options that maximized reward more often than did younger adults in three of the four tasks, and modeling results suggested reduced model-based strategy use. In the task where older adults showed similar behavior to younger adults, our model-fitting results suggested that this was due to the utilization of a win-stay–lose-shift heuristic rather than a more complex model-based strategy. Additionally, within older adults, we found that model-based strategy use was positively correlated with memory measures from our neuropsychological test battery. We suggest that this shift from state-based to reward-based motivation may be due to age related declines in the neural structures needed for more computationally demanding model-based decision making.     

异体造血干细胞移植问题、发展与思考

异体造血干细胞移植(Allo-HSCT)已成为治疗恶性血液病及其他各种疾病的有效方法之一。在Allo-HSCT中由于供体和受体免疫屏障的存在。从而一开始就是一个供受体矛盾的对立统一的过程。对其中矛盾的研究和解决充满了辩证唯物的哲学思想。也促使Allo-HSCT技术不断发展。新的方法和理念不断出现。使Allo-HSCT治疗白血病的疗效不断提高。     

Information about foregone rewards impedes dynamic decision-making in older adults

“Making an informed decision” implies that more information leads to better decisions, yet it may be the case that additional information biases decisions in a systematic and sometimes detrimental manner. In the present study, we examined the effect of additional information on older adults’ decision-making using a task for which available rewards were dependent on the participant’s recent pattern of choices. The optimal strategy was to forego the immediately rewarding option in favor of the option that yielded larger delayed reward. We found that providing information about true foregone rewards – the reward that would have been received had the participant chosen the other option – significantly reduced older adults’ decision-making performance. However, false foregone rewards – foregone rewards manufactured to make the long-term option appear more immediately rewarding – led older adults to perform at a level equal to younger adults. We conclude that providing information about foregone rewards biases older adults toward immediate rewards at a greater rate than younger adults, leading to poorer older adult performance when immediate rewards and long-term rewards conflict, but intact performance when immediate rewards and long-term rewards appear to align.     

退步原来是向前

从契此的“手把青苗插满田,低头便见水中天,六根清净方为道,退步原来是向前”偈中,反映了退让并不是完全的消极,有时反而是一种积极的进取,从而揭示出丰富的人生哲理。     

苏辙“示疾而病”的禅学思想

＂多病则与学道者宜,多难则与学禅者宜＂,苏辙却因有＂喜汝因病悟,或免终身著＂的示疾而病的禅学思想。＂示疾而病＂的苏辙以维摩自喻,在深层意义上,是他借维摩诘而表现其忧以天下、以乐天下的人格理想。     

Regulatory fit effects in a choice task

This article examines the interface between motivation and choice. In category learning, a regulatory fit has been shown to increase exploration of alternative response strategies even when exploration is suboptimal. In the present study, promotion- and prevention-focused subjects performed a choice task that required them to choose from one of two decks of cards on each trial. They either gained or lost points with each draw. In Experiment 1, optimal performance required an exploratory response pattern that entailed sampling from a deck that initially appeared disadvantageous but ultimately became advantageous. In Experiment 2, optimal performance required an exploitative response pattern. A softmax action selection model that includes an exploitation parameter was applied to each subject’s data from both experiments and revealed greater exploration of alternative strategies for people with a regulatory fit. This response strategy was optimal in Experiment 1 and led to superior performance, but was suboptimal in Experiment 2 and led to inferior performance.     

What is pressure? Evidence for social pressure as a type of regulatory focus

Previous research (Markman, Maddox, & Worthy, 2006) suggests that pressure leads to choking when one is learning to classify items on the basis of an explicit rule, but it leads to excelling when one is learning to classify items on the basis of an implicit strategy. In this article, we relate social pressure to regulatory focus theory. We propose that the effects of pressure on performance arise because pressure induces a prevention focus that interacts with the more local reward structure of the task. To test this hypothesis, we repeated previous research, but using a losses reward structure, so that participants under pressure were in a regulatory fit. We also successfully replicated previous results by using a gains reward structure. In contrast with participants who attempted to maximize gains on each trial, participants who attempted to minimize losses choked on the implicit-learning task but excelled on the explicit-learning task. The results suggest a three-way interaction between pressure level, task type, and reward structure.     

试论卫生与法律的关系

卫生是人类重要的社会实践活动。卫生也是保护人体健康的重要社会事业,需要法律的保护和导向。卫生法为卫生发展提供了良好的社会环境,并控制医药卫生无序、失控及异化带来的社会危害性,造福人类,促进经济发展和社会进步。