敬畏对跨期选择的影响：时间洞察力和时距敏感度的作用

本研究考察了情绪(敬畏、愉悦和中性)对跨期选择的影响机制,以及时距敏感度和时间洞察力在其中的作用。结果显示：(1)相比中性,敬畏情绪下个体的折扣率更大;(2)相比中性,敬畏情绪下折扣率降幅更大;(3)对于未来取向者,敬畏情绪下折扣率比中性条件下更大;(4)对于现在取向者,敬畏情绪下折扣率降幅比中性条件下更大。结果表明,敬畏情绪通过未来时距的敏感度影响跨期选择偏好,使个体更加偏好延迟奖赏,同时,个体的时间取向在其中起调节作用。     

时间洞察力特质对食品选择偏好的影响:解释水平对内隐偏好的作用

探索两类时间洞察力特质个体外显与内隐食物选择偏好。实验1用《津巴多时间洞察力问卷》选出"现在享乐"和"未来定向"两类个体,考察其外显食物选择偏好,结果发现,与"未来定向"组相比,"现在享乐"个体选择更多垃圾食品。实验2中,两类个体分别接受不同的解释水平操作,之后完成单靶内隐联想测验,以考察其对垃圾食品的内隐态度,并检验解释水平的调节作用。结果发现,与未来定向组相比,现在享乐组对"垃圾食品"存在内隐偏好。此外,对现在享乐者,解释水平改变会对食物选择偏好有显著影响;而对未来定向者,其影响不显著。这表明与未来时间定向者比,现在享乐者在外显、内隐层面对"垃圾食品"有选择偏好,并且解释水平会通过改变心理距离对其内隐选择偏好产生影响。     

中学生时间洞察力特质与健康行为选择内隐偏好：未来情景性思维的作用

本研究采用经典内隐联想测验任务,研究了现在享乐、现在宿命和未来三种时间洞察力特质中学生的健康行为选择内隐偏好以及未来情景性思维在时间洞察力类型与健康行为选择内隐偏好中的调节作用。结果发现：未来特质中学生的健康行为选择内隐偏好高于现在享乐和现在宿命特质中学生;未来情景性思维水平在中学生时间洞察力类型与健康行为选择内隐偏好的关系中起调节作用,即未来情景性思维显著提高现在享乐和未来特质中学生的健康行为选择内隐偏好,而对现在宿命特质的作用不显著。本研究的发现表明未来时间洞察力特质是中学生选择健康行为的积极因素;未来情景性思维能促进现在享乐和未来时间洞察力特质中学生的健康行为选择内隐偏好。     

未来情景想象对海洛因戒断者跨期决策的影响

大量研究发现海洛因成瘾者在跨期决策中更加偏好即时奖赏,对延迟奖赏具有更高的延迟折扣率。本研究采用延迟折扣任务探讨了未来情景想象对海洛因戒断者跨期决策的影响。实验1结果发现,前测中海洛因戒断组在金钱延迟折扣任务中的曲线下面积(the areas under the curve, AUC)显著小于对照组,而未来情景想象后两组被试的AUC值没有显著差异。而且海洛因戒断组在两种条件的AUC差值显著大于对照组。实验2结果发现,海洛因戒断组在前测的跨类别延迟折扣任务中的AUC值显著小于其未来情景想象后的AUC值。鉴于未来情景想象可以改善海洛因戒断者的跨期决策表现,今后可采用未来情景想象展开针对海洛因成瘾者跨期决策的靶向干预,降低海洛因成瘾者复吸的风险。     

适应性时间管理：死亡意识对时间知觉和跨期决策的影响

死亡意识是个体对自身死亡必然性的认识; 基于进化适应性的考量, 作者认为具有前瞻性的死亡意识作为人类特有的认知能力和个体生命史的终极坐标, 不仅可能引起恐惧感和防御反应, 更重要的是可以帮助人们做出适应性的时间管理。据此推论, 死亡意识的启动会加强人们对时间有限性的关注, 体验出更强的时间流逝感, 影响人们对时间的评估, 以及人们对不同时间点的成本与收益进行权衡而做出的跨期决策。本研究采用死亡凸显范式启动死亡意识, 通过两个实验探讨了死亡意识、时间知觉和跨期决策三者之间的关系。结果发现, 死亡意识启动使被试低估时间距离, 并表现出较低的跨期决策延迟折扣率, 从而在较小的即时获益与更大的延迟的获益之间更为偏好未来导向的选项。进一步的分析显示, 时间知觉在死亡意识和跨期决策延迟折扣率之间起到部分中介变量的作用。以上的研究结果初步揭示了死亡意识在时间管理上的适应性价值。     

时间方向等因素影响跨期决策的实验研究

跨期决策中主要存在三个价值不对等现象:时间折扣、符号效应和过去、未来的价值不对等,上述不对等现象涉及到时间距离、时间方向和损益情境三个主要评价维度。本研究旨在通过实验考察时间距离、时间方向和损益情境在跨期决策中的相互作用。通过设置获益(中奖)和损失(罚款)的假想场景,要求被试对不同时间距离、不同时间方向上的决策任务作出判断,根据双曲模型,计算时间折扣率。结果,时间距离影响未来方向决策,而不影响过去方向决策;相同时间距离条件下,未来方向折扣率显著大于过去方向折扣率;损失折扣率大于获益折扣率,得到"反符号效应"。     

资源困境中共同收益延迟的影响：时间折扣的调节效应

通过测量83名大学生的时间折扣率和不同共同收益延迟时距上的金币拿取量,以探讨资源困境中共同收益延迟对个体决策的影响及时间折扣的调节效应。结果表明：（1）金币拿取量随共同收益延迟时距的增长而增加,增加趋势和初始时间点的金币拿取量均存在显著的个体差异;（2）时间折扣率反向调节初始延迟时间点的金币拿取量,正向调节金币拿取量随延迟时距增长而增加的速率。这表明资源困境与跨期选择两个不同研究领域具有紧密联系,对当前资源保护制度的制定与实施具有一定的启发意义。     

跨期选择的性质探索

跨期选择指人们对发生在不同时间点的价值做出的权衡与决策。大量研究证明, 跨期选择中人们存在普遍的时间折扣倾向, 即将未来的价值折扣后与当前价值进行权衡。跨期选择研究不仅与人类心智的起源与机制等基础科学问题密切相关, 也关系到国家公共政策的制定等现实问题。本项目拟采用实验室研究和大规模问卷调查结合的方法, 深入探索跨期选择的本质。一方面, 采用实验室研究法探讨影响跨期选择的重要因素, 以探索：(1) 跨期选择的效价及其与价值数量、延迟时间的交互作用及其心理机制; (2) 跨期选择中是否存在领域特异性及其心理机制; 另一方面, 通过全国范围的调查, 从而：(1) 建立中国城镇居民时间折扣率的常模; (2) 测量不同类型人群的时间折扣率, 以探讨跨期选择的性质与内涵。项目研究结果将有利于加深学界对跨期选择现象的理解。     

佤族与汉族大学生的跨期决策：时间知觉的作用？

为探究佤族大学生的跨期决策偏好,本研究采用多领域的跨期决策任务,通过对比佤族和汉族大学生跨期决策和时间知觉特点,探讨了民族文化对不同领域延迟折扣的影响,以及时间知觉的中介作用。结果表明,金钱领域中,佤族与汉族之间的延迟折扣率无明显差异;而在健康和环境领域中,佤族延迟折扣率显著低于汉族,更偏好将来更大的收益;佤族的时间知觉显著小于汉族,并且时间知觉在民族和各领域延迟折扣之间起到了中介作用。     

金钱崇拜对个体跨期决策偏好的影响

采用经典跨期选择任务范式,以个体的金钱喜好差异为切入点,通过问卷调查和行为实验考察金钱崇拜对个体跨期决策偏好的影响。结果发现:(1)个体的金钱崇拜水平与其跨期折扣倾向显著负相关;(2)无论跨期决策任务的难易和兑现时间的长短,高金钱崇拜者更倾向于选择较大的延迟奖赏,而低金钱崇拜者更倾向于选择较小的即时奖赏;(3)高、低金钱崇拜者的跨期决策反应时没有明显的差异,但二者的反应时都明显地受到任务难度的影响,即在容易条件下的反应速度显著快些。结果表明,个体的金钱崇拜水平在跨期决策过程中发挥着重要的作用,致使高金钱崇拜者更愿意等待延迟大奖赏的到来。     

跨期选择的认知机制与神经基础

跨期选择是指个体对发生在不同时间的成本与收益进行权衡的决策过程。跨期选择的计算模型从经济学的角度用数学模型来建构时间折扣函数,而认知成分模型则从心理学的角度来研究跨期选择中的心理效应与认知成分。跨期选择的神经基础有三种不同的研究取向：双机制加工取向、单机制加工取向、自我控制取向。未来研究应该在跨期选择的认知机制、神经通路及运行机制、跨期选择的应用,以及从进化的角度对人与动物的跨期选择行为进行更深入的研究。     

Testing the effect of risk on intertemporal choice in the Chinese cultural context

Previous studies using Western samples have found that introducing uncertainty to an intertemporal choice decreases the degree of discounting future rewards. The authors of this article examined the effect of risk on intertemporal choice using Chinese participants and found that respondents preferred the smaller but sooner (SS) outcome to the larger but later (LL) one in the presence of risk, which indicates that risk increases rather than decreases the degree of discounting future rewards. Thus, variations in response patterns between different cultural groups suggest that culture may play an important role in intertemporal choice and researchers should delve into this topic from an emic rather than an etic perspective.     

不确定性容忍度对跨期选择的影响及其情景依赖性

采用2(不确定性容忍度：高、低)×2(跨期日期：今天/14天、今天/180天)×2(延迟奖赏值：200元、1000元)混合实验设计,探讨不同任务特征下不确定性容忍度对跨期选择的影响。结果表明：跨期日期为180天时,不确定性容忍度主效应边缘显著;不确定性容忍度与延迟奖赏值交互作用显著：在200元时低容忍度个体对延迟奖赏的折扣程度大于高容忍度个体,在1000元时无此效应;跨期日期为14天时,不确定性容忍度的主效应及其与延迟奖赏值交互作用均不显著。这表明,不确定性容忍度对跨期选择存在影响,但这种影响受到跨期日期和延迟奖赏值的调节,具有情景依赖性。     

Thinking about others and the future: Neural correlates of perspective taking relate to preferences for delayed rewards

We infer the thoughts and feelings of others by taking their perspectives. Similar processes could be used to understand how we will be affected by future events, by allowing us to take the perspective of our future self. In this paper, we test this idea using a previously presented framework for guiding predictions. The framework proposes that a shared neural mechanism is involved in controlling egocentric bias, both while shifting our perspective away from self and towards others, and while shifting our perspective from immediate to future perspectives. To test this framework, 36 adults performed an intertemporal choice task. They were then scanned using 3T functional magnetic resonance imaging while completing a false-belief “localizer” task, which requires egocentric bias control. A positive correlation was observed between the right temporoparietal junction (rTPJ) response during the false-belief task, and preferences for delayed rewards in intertemporal choices. A subset of participants performed the intertemporal choice task again in the scanner, which revealed that the response of the same rTPJ cluster, individually localized during the false-belief task, was higher during delayed over immediate reward choices. In addition, functional connectivity between the rTPJ and ventromedial prefrontal cortex was found to differ between immediate and delayed choices. The current results indicate an overlap in processes of egocentric bias control and those that determine preferences in intertemporal choices, offering a social cognitive explanation for why rewards are devalued with delay in temporal discounting.     

负折扣现象:跨期决策中的自我-他人决策差异

负折扣现象作为一种违背时间折扣假定的现象越来越多地引起研究者关注。本文通过两种指标考察了为自己决策和为他人决策在负折扣现象上的差异。实验1运用二择一选择范式考察人们在为自己决策和为他人决策时对于何时发生负性事件的时间偏好。结果发现,相比较于为他人决策,为自己决策时被试更倾向于选择早些发生负性事件,即更容易产生负折扣现象。实验2运用测量时间折扣率的经典范式考察了人们在为自己决策和为他人决策时的时间折扣率。结果发现,为自己决策时比为他人决策时的时间折扣率更小,更容易出现负折扣率。总体结果表明,为自己决策比为他人决策更容易出现负折扣现象。从情绪卷入的角度看,我们推测,为自己决策时由于更多的预期负性情绪卷入,从而导致更容易产生负折扣现象。     

Intertemporal Similarity: Discounting as a Last Resort

Standard models of intertemporal choice assume that individuals discount future payoffs by integrating reward amounts and time delays to generate a discounted value. Alternative models propose that, rather than integrate across them, individuals compare within attributes (amounts and delays) to determine if differences in one attribute outweigh differences in another attribute. For instance, the similarity model 1) compares the two reward amounts to determine whether they are similar, 2) compares the similarity of the two time delays, and then 3) makes a decision based on these similarity judgments. Here, I tested discounting models against attribute‐based models that use similarity judgments to make choices. I collected intertemporal choices and similarity judgments for the reward amounts and time delays from participants in three experiments. All experiments tested the ability of discounting and similarity models to predict intertemporal choices. Model generalization analyses showed that the best predicting models started with similarity judgments and then, if similarity failed to make a prediction, resorted to discounting models. Similarity judgments also matched intertemporal choice data demonstrating both the magnitude and sign effects, thereby accounting for behavioral data that contradict many discounting models. These results highlight the possibility that attribute‐based models such as the similarity models provide alternatives to discounting that may offer insights into the process of making intertemporal choices. Copyright © 2015 John Wiley & Sons, Ltd.     

厌恶和恐惧情绪对跨期选择的不同影响：基于ERP的研究

本研究运用事件相关电位技术(ERPs)考察厌恶和恐惧情绪对跨期选择的影响。其中,厌恶和恐惧情绪采用情绪面孔图片进行启动,分析跨期选择任务中评估阶段所诱发的ERP成分。行为结果发现,与中性面孔相比,厌恶面孔启动使个体倾向于选择立即奖赏。ERP结果发现,在选项评估阶段,厌恶面孔比中性和恐惧面孔启动诱发更大的P2、P3和LPP波幅。这说明,厌恶情绪促使个体投入更多的注意和动机资源对跨期选项进行评估,进而使个体倾向即时满足。     

Time discounting and time preference in animals: A critical review

Animals are an important model for studies of impulsivity and self-control. Many studies have made use of the intertemporal choice task, which pits small rewards available sooner against larger rewards available later (typically several seconds), repeated over many trials. Preference for the sooner reward is often taken to indicate impulsivity and/or a failure of self-control. This review shows that very little evidence supports this assumption; on the contrary, ostensible discounting behavior may reflect a boundedly rational but not necessarily impulsive reward-maximizing strategy. Specifically, animals may discount weakly, or even adopt a long-term rate-maximizing strategy, but fail to fully incorporate postreward delays into their choices. This failure may reflect learning biases. Consequently, tasks that measure animal discounting may greatly overestimate the true discounting and may be confounded by processes unrelated to time preferences. If so, animals may be much more patient than is widely believed; human and animal intertemporal choices may reflect unrelated mental operations; and the shared hyperbolic shape of the human and animal discount curves, which is used to justify cross-species comparisons, may be coincidental. The discussion concludes with a consideration of alternative ways to measure self-control in animals.     

Good or Bad,We Want it Now: Fixed‐cost Present Bias for Gains and Losses Explains Magnitude Asymmetries in Intertemporal Choice

Intertemporal tradeoffs are ubiquitous in decision making, yet preferences for current versus future losses are rarely explored in empirical research. Whereas rational‐economic theory posits that neither outcome sign (gains vs. losses) nor outcome magnitude (small vs. large) should affect delay discount rates, both do, and moreover, they interact: in three studies, we show that whereas large gains are discounted less than small gains, large losses are discounted more than small losses. This interaction can be understood through a reconceptualization of fixed‐cost present bias, which has traditionally described a psychological preference for immediate rewards. First, our results establish present bias for losses—a psychological preference to have losses over with now. Present bias thus predicts increased discounting of future gains but decreased (or even negative) discounting of future losses. Second, because present bias preferences do not scale with the magnitude of possible gains or losses, they play a larger role, relative to other motivations for discounting, for small magnitude intertemporal decisions than for large magnitude intertemporal decisions. Present bias thus predicts less discounting of large gains than small gains but more discounting of large losses than small losses. The present research is the first to demonstrate that the effect of outcome magnitude on discount rates may be opposite for gains and losses and also the first to offer a theory (an extension of present bias) and process data to explain this interaction. The results suggest that policy efforts to encourage future‐oriented choices should frame outcomes as large gains or small losses. Copyright © 2012 John Wiley & Sons, Ltd.