Prospective emotion enables episodic prospection to shift time preference

The episodic effect suggests that episodic prospection (imagining future events) can effectively reduce time discounting, the propensity to discount the value of delayed rewards relative to immediate ones. However, less clear is how episodic prospection modulates time preference. As engagement in episodic prospection usually evokes prospective emotions, it was proposed that episodic prospection might work by inducing prospective emotions. Although one previous study has attempted to provide evidence to the emotional account of the episodic effect, shortcomings in its experimental design make its conclusion questionable. In this study, we replicated previous experimental design with improvements to further test the effects of prospective emotion on time preference. By manipulating the emotional valency associated with episodic prospection in a delay discounting task, we found that positive episodic prospection attenuated time discounting; negative episodic prospection exacerbated time discounting; and episodic prospection did not shift time preference when prospective emotion is removed. These results were essentially identical to the result of the previous study. Together, these studies suggested that the effects of episodic prospection depended on prospective emotion. Thus, one cannot ignore prospective emotion if counting on episodic prospection to combat humans’ impulsive behaviours.     

Preference reversals with losses

People who prefer larger, later gains over smaller, sooner gains when considering outcomes far in the future often reverse their preference as the alternatives become closer in time. This finding, which is contrary to a normative economic account of intertemporal choice, has been interpreted as support for hyperboloid discounting, but the results can also be explained by steeper discounting of smaller amounts. The present study is the first to demonstrate that analogous preference reversals occur with losses: People who preferred a smaller, sooner loss over a larger, later loss when the outcomes were far in the future reversed their preference when these alternatives were closer in time. Because there was no magnitude effect (i.e., smaller losses were not discounted more steeply than larger losses), the present findings strongly support the proposition that reversals in preference between delayed outcomes occur because of the hyperboloid shape of the discounting function.     

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.     

Impulsivity in borderline personality disorder: reward-based decision-making and its relationship to emotional distress

Impulsivity in Borderline Personality Disorder (BPD) has been defined as rapid and unplanned action. However, a preference for immediate gratification and discounting of delayed rewards might better account for the impulsive behaviors that appear to regulate emotional distress in BPD. To investigate this, a delay discounting task was administered to 30 outpatients diagnosed with BPD and 28 healthy community controls (all aged 15-24) before and after a mood induction. Trait impulsivity was measured with the Barratt Impulsiveness Scale. The results showed that the BPD group had a greater preference for immediate gratification and higher rate of discounting the delayed reward than the control group. Although the mood induction resulted in increased feelings of rejection and anger in all participants, and the rate of delay discounting changed significantly in the control group, the rate of discounting did not change for the BPD group. There was no evidence of rapid decision-making in the BPD group as response times were similar between the two groups during both trials. Finally, greater general impulsiveness and nonplanning impulsiveness were associated with greater rates of discounting in the BPD group. Together these findings suggest that BPD is characterized by a preference for immediate gratification and tendency to discount longer-term rewards. This characteristic appears to exist independent of feelings of rejection and anger, rather than being reactive to this, and to be related to trait impulsivity.     

概率贴现和时间贴现在人脑中的分离

本研究运用ERP技术来检验概率贴现和时间贴现是否反映了相同的神经机制过程。在本研究中,我们在一个刺激中同时操纵概率贴现（风险vs.安全）和时间贴现（1个月后vs.今天）水平。通过对两个过程上的ERN以及全时间段的ERP分析来确定它们是否反映了相同的认知过程。结果发现,这两者在ERN上存在差异,同时这两个效应在ERP的时程和出现的电极点上都存在差异。这些差异表明这两者可能包含着不同的神经机制过程。     

Introduction to the special issue on comparative cognition

Prior research has shown that nonhumans show an extreme preference for variable‐ over fixed‐delays to reinforcement. This well‐established preference for variability occurs because a reinforcer's strength or “value” decreases according to a curvilinear function as its delay increases. The purpose of the present experiments was to investigate whether this preference for variability occurs with human participants making hypothetical choices. In three experiments, participants recruited from Amazon Mechanical Turk made choices between variable and fixed monetary rewards. In a variable‐delay procedure, participants repeatedly chose between a reward delivered either immediately or after a delay (with equal probability) and a reward after a fixed delay (Experiments 1 and 2). In a double‐reward procedure, participants made choices between an alternative consisting of two rewards, one delivered immediately and one after a delay, and a second alternative consisting of a single reward delivered after a delay (Experiments 1 and 3). Finally, all participants completed a standard delay‐discounting task. Although we observed both curvilinear discounting and magnitude effects in the standard discounting task, we found no consistent evidence of a preference for variability—as predicted by two prominent models of curvilinear discounting (i.e., a simple hyperbola and a hyperboloid)—in our variable‐delay and double‐reward procedures. This failure to observe a preference for variability may be attributed to the hypothetical, rule‐governed nature of choices in the present study. In such contexts, participants may adopt relatively simple strategies for making more complex choices.     

Subadditive versus hyperbolic discounting: A comparison of choice and matching

Impulsive and myopic choices are often explained as due to hyperbolic discounting, meaning that people are impatient for outcomes available immediately, and become increasingly more patient the more the outcome is delayed. Recent research, however, has suggested that much experimental evidence for increasing patience is actually due to subadditive discounting: people are less patient (per-time-unit) over shorter intervals regardless of when they occur. Because previous research into subadditive discounting has used a choice elicitation procedure, the present paper tests whether it generalises to matching. We find strong evidence that it does, but also find weak evidence of increasing patience for matching. We suggest, however, that subadditive discounting alone may be sufficient to account for all of our results. We conclude by questioning the contribution that hyperbolic discounting makes to our understanding of time preference.     

Asymmetry of the group context effect on delay discounting

Binary choice delay discounting tasks require participants to indicate preference between smaller, immediate, and larger, delayed rewards. Previous research indicates that when the delayed reward is shared with others, the delayed outcome is preferred compared with when the outcomes are for the self only, resulting in lower rates of delay discounting. The present series of studies sought to replicate and extend this finding. Study 1 compared delay discounting on a standard task in which both immediate and delayed outcomes are for the self and a group context task where the delayed outcome was shared with one other person. Replicating previous results, group context resulted in lower rates of delay discounting, and this effect was independent of how the shared outcome was presented. Study 2 compared delay discounting on a standard task and a group context task where the immediate outcome was shared. In contrast to Study 1, group context resulted in higher rates of delay discounting, suggesting that preference in intertemporal choice tracks the shared outcome. Moreover, this effect was not independent of how the shared outcome was presented. This is the first study to reveal that group context, when applied to the immediate outcome, can result in higher rates of delay discounting.     

Discounting of probabilistic rewards is associated with gambling abstinence in treatment-seeking pathological gamblers

Individuals with addictive disorders, including substance abusers and pathological gamblers, discount or devalue rewards delayed in time more than controls. Theoretically, preference for probabilistic rewards is directly related to gambling, but limited empirical research has examined probabilistic discounting in individuals with pathological gambling. This study evaluated probability and delay discounting in treatment-seeking pathological gamblers and their association with gambling treatment outcomes during and after treatment. At time of treatment entry, 226 pathological gamblers completed probability and delay discounting tasks. They were then randomized to one of three treatment conditions, and gambling behavior was measured throughout treatment and at a 1-year follow-up assessment. After controlling for possibly confounding variables and treatment condition, more shallow probability discounting was associated with greater reductions in amounts wagered during treatment and likelihood of gambling abstinence at the end of treatment and throughout the follow-up period. No associations were noted between delay discounting and gambling treatment outcomes. These data suggest that probability discounting may be an important construct in understanding pathological gambling and its treatment.     

A second type of magnitude effect: Reinforcer magnitude differentiates delay discounting between substance users and controls

Basic research on delay discounting, examining preference for smaller–sooner or larger–later reinforcers, has demonstrated a variety of findings of considerable generality. One of these, the magnitude effect, is the observation that individuals tend to exhibit greater preference for the immediate with smaller magnitude reinforcers. Delay discounting has also proved to be a useful marker of addiction, as demonstrated by the highly replicated finding of greater discounting rates in substance users compared to controls. However, some research on delay discounting rates in substance users, particularly research examining discounting of small‐magnitude reinforcers, has not found significant differences compared to controls. Here, we hypothesize that the magnitude effect could produce ceiling effects at small magnitudes, thus obscuring differences in delay discounting between groups. We examined differences in discounting between high‐risk substance users and controls over a broad range of magnitudes of monetary amounts ($0.10, $1.00, $10.00, $100.00, and $1000.00) in 116 Amazon Mechanical Turk workers. We found no significant differences in discounting rates between users and controls at the smallest reinforcer magnitudes ($0.10 and $1.00) and further found that differences became more pronounced as magnitudes increased. These results provide an understanding of a second form of the magnitude effect: That is, differences in discounting between populations can become more evident as a function of reinforcer magnitude.     

Delay discounting of different outcomes: Review and theory

Steep delay discounting is characterized by a preference for small immediate outcomes relative to larger delayed outcomes and is predictive of drug abuse, risky sexual behaviors, and other maladaptive behaviors. Nancy M. Petry was a pioneer in delay discounting research who demonstrated that people discount delayed monetary gains less steeply than they discount substances with abuse liability. Subsequent research found steep discounting for not only drugs, but other nonmonetary outcomes such as food, sex, and health. In this systematic review, we evaluate the hypotheses proposed to explain differences in discounting as a function of the type of outcome and explore the trait- and state-like nature of delay discounting. We found overwhelming evidence for the state-like quality of delay discounting: Consistent with Petry and others' work, nonmonetary outcomes are discounted more steeply than monetary outcomes. We propose two hypotheses that together may account for this effect: Decreasing Future Preference and Decreasing Future Worth. We also found clear evidence that delay discounting has trait-like qualities: People who steeply discount monetary outcomes steeply discount nonmonetary outcomes as well. The implication is that changing delay discounting for one outcome could change discounting for other outcomes.     

The strategies in past temporal discounting

对过去事件的加工涉及到对现在信息的加工,过去获得的价值能够为现在的生活带来的收益可能对过去事件的价值估计具有影响。本研究探讨了过去事件对现在生活的影响在过去时间贴现中的作用。采用延迟时间贴现范式任务,选取2周到50年共10个过去时间长度,要求被试在现在获得的奖金和过去获得的奖金之间进行偏好选择,并且完成对过去时间贴现决策策略的问题回答。采用曲线下的单位面积UAUr(t1,t1) 为过去时间贴现率,发现过去时间贴现率在过去2周和过去1个月之间[Z = 2.662,p = .008]、过去1年和过去3年之间[Z = 2.587, p = .010] 差异显著。对决策策略的回答进行内容分析(频次统计信度为0.875),发现过去事件能够为现在生活带来的收益影响了被试对过去事件的价值估计和偏好选择。从现在起到过去2周内,被试看重近的过去获得的奖金对现在的生活的帮助,偏好选择过去获得的奖金;在较远的过去,从过去2周起到过去1年内,奖金数量和获得奖金的时间之间的比例影响了被试的偏好选择;从过去1年起到过去50年内,远的过去获得的奖金对现在生活的影响微乎其微,被试偏好现在获得的奖金。本研究的结果支持了过去时间贴现和未来时间贴现具有不同的心理加工机制,并且有助于进一步了解过去时间的差别感受性的变化规律。     

Change we can believe in: using perceptions of changeability to promote system-change motives over system-justification motives in information search

People are motivated to defend and rationalize the status quo, a phenomenon known as system justification. We propose the existence of a second, countervailing system-level motivation: system-change motivation, which is concerned with bettering the status quo over time. The opportunity to receive diagnostic information about the status quo pits the two system-level motives against each other. Whereas system justification promotes a preference for positive information about the status quo, system-change motivation promotes a preference for negative information about the status quo. In three experiments, we found that people preferred negative over positive feedback about the status quo when it was presented as being changeable. Our findings are the first to suggest the operation of a system-change motive.     

Perception and preference in short-term word priming

Responding optimally with unknown sources of evidence (ROUSE) is a theory of short-term priming applied to associative, orthographic-phonemic, and repetition priming. In our studies, perceptual identification is measured with two-alternative forced-choice testing. ROUSE assumes features activated by primes are confused with those activated by the target. A near-optimal decision discounts evidence arising from such shared features. Too little discounting explains the finding that primed words were preferred after passive viewing of primes. Too much discounting explains the findings of reverse preference after active processing of primes. These preference changes highlight the need to use paradigms (like the present ones) capable of separating preferential and perceptual components of priming. Evidence of enhanced perception was found only with associative priming and was very small in magnitude compared with preference effects.     

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。     

A discounting framework for choice with delayed and probabilistic rewards

When choosing between delayed or uncertain outcomes, individuals discount the value of such outcomes on the basis of the expected time to or the likelihood of their occurrence. In an integrative review of the expanding experimental literature on discounting, the authors show that although the same form of hyperbola-like function describes discounting of both delayed and probabilistic outcomes, a variety of recent findings are inconsistent with a single-process account. The authors also review studies that compare discounting in different populations and discuss the theoretical and practical implications of the findings. The present effort illustrates the value of studying choice involving both delayed and probabilistic outcomes within a general discounting framework that uses similar experimental procedures and a common analytical approach.     

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。     

A hierarchical state space approach to affective dynamics

Linear dynamical system theory is a broad theoretical framework that has been applied in various research areas such as engineering, econometrics and recently in psychology. It quantifies the relations between observed inputs and outputs that are connected through a set of latent state variables. State space models are used to investigate the dynamical properties of these latent quantities. These models are especially of interest in the study of emotion dynamics, with the system representing the evolving emotion components of an individual. However, for simultaneous modeling of individual and population differences, a hierarchical extension of the basic state space model is necessary. Therefore, we introduce a Bayesian hierarchical model with random effects for the system parameters. Further, we apply our model to data that were collected using the Oregon adolescent interaction task: 66 normal and 67 depressed adolescents engaged in a conflict-oriented interaction with their parents and second-to-second physiological and behavioral measures were obtained. System parameters in normal and depressed adolescents were compared, which led to interesting discussions in the light of findings in recent literature on the links between cardiovascular processes, emotion dynamics and depression. We illustrate that our approach is flexible and general: The model can be applied to any time series for multiple systems (where a system can represent any entity) and moreover, one is free to focus on various components of this versatile model.     

Associations between a one-shot delay discounting measure and age, income, education and real-world impulsive behavior

There has been discussion over the extent to which delay discounting – as prototypically shown by a preference for a smaller-sooner sum of money over a larger-later sum – measures the same kind of impulsive preferences that drive non-financial behavior. To address this issue, a dataset was analyzed containing 42,863 participants’ responses to a single delay-discounting choice, along with self-report behaviors that can be considered as impulsive. Choice of a smaller-sooner sum was associated with several demographics: younger age, lower income, and lower education; and impulsive behaviors: earlier age of first sexual activity and recent relationship infidelity, smoking, and higher body mass index. These findings suggest that at least an aspect of delay discounting preference is associated with a general trait influencing other forms of impulsivity, and therefore that high delay discounting is another form of impulsive behavior.     

Associations between a one-shot delay discounting measure and age,income, education and real-world impulsive behavior

There has been discussion over the extent to which delay discounting – as prototypically shown by a preference for a smaller-sooner sum of money over a larger-later sum – measures the same kind of impulsive preferences that drive non-financial behavior. To address this issue, a dataset was analyzed containing 42,863 participants’ responses to a single delay-discounting choice, along with self-report behaviors that can be considered as impulsive. Choice of a smaller-sooner sum was associated with several demographics: younger age, lower income, and lower education; and impulsive behaviors: earlier age of first sexual activity and recent relationship infidelity, smoking, and higher body mass index. These findings suggest that at least an aspect of delay discounting preference is associated with a general trait influencing other forms of impulsivity, and therefore that high delay discounting is another form of impulsive behavior.