Relationship between an inconsistent degree of financial literacy and inconsistent decision-making in intertemporal choices

Intertemporal choice refers to the decision-making process involving trade-offs between rewards available at different points in time (such as choosing between smaller immediate rewards versus larger rewards later on). Empirical evidence often deviates from the exponential preferences predicted by the normative model. A hyperbolic discount function better mirrors individual behavior, explaining temporal inconsistency - whereby preferences vary over time by applying a higher discount in the present. Hyperbolic preferences are associated with addictive behaviors, such as smoking and alcohol consumption, as well as depression or attention deficit hyperactivity disorder. Established measures in the literature quantify the extent of deviation from exponential trend exhibited by hyperbolic preferences. In addition to behavioral and cognitive factors, it is essential to incorporate financial literacy into the examination of individual decision-making behaviors. The present study analyzes the relationship between the degree of decision-making inconsistency and the degree of financial literacy inconsistency across three dimensions: knowledge, behavior, and attitudes. It aims to illustrate while financial literacy is important, it is not sufficient to ensure rational choices. Rather, it reveals a strong correlation among its dimensions. The results of this research could be included when creating investor profiles required by MiFID, considering insights from behavioral finance studies in these profiles. What is more, understanding psychological biases that can influence financial decision-making empowers investors to make more informed decisions and avoid common pitfalls.

Modulating preferences during intertemporal choices through exogenous midfrontal transcranial alternating current stimulation: A registered report

Decision conflicts may arise when the costs and benefits of choices are evaluated as a function of outcomes predicted along a temporal dimension. Electrophysiology studies suggest that during performance monitoring a typical oscillatory activity in the theta rhythm, named midfrontal theta, may index conflict processing and resolution. In the present within-subject, sham controlled, cross-over preregistered study, we delivered online midfrontal transcranial Alternating Current Stimulation (tACS) to modulate electrocortical activity during intertemporal decisions. Participants were invited to select choice preference between economic offers at three different intermixed levels of conflict (i.e., low, medium, high) while receiving either theta -, gamma-, or sham tACS in separate blocks and sessions. At the end of each stimulation block, a Letter-Flanker task was also administered to measure behavioural aftereffects. We hypothesized that theta-tACS would have acted on the performance monitoring system inducing behavioural changes (i.e., faster decisions and more impulsive choices) in high conflicting trials, rather than gamma- and sham-tACS. Results very partially confirmed our predictions. Unexpectedly, both theta- and gamma-driven neuromodulation speeded-up decisions compared to sham. However, exploratory analyses revealed that such an effect was stronger in the high-conflict decisions during theta-tACS. These findings were independent from the influence of the sensations induced by the electrical stimulation. Moreover, further analyses highlighted a significant association during theta-tACS between the selection of immediate offers in high-conflict trials and attentional impulsiveness, suggesting that individual factors may account for the tACS effects during intertemporal decisions. Finally, we did not capture long-lasting behavioural changes following tACS in the Flanker task. Our findings may inform scholars to improve experimental designs and boost the knowledge toward a more effective application of tACS.

A formal analysis of inconsistent decisions in intertemporal choice through subjective time perception

The framework of this paper is subjective time perception in the context of intertemporal choice, that is to say, the process of making decisions on dated outcomes (monetary or not) by an individual or a group of individuals. In this setting, the Discounted Utility model and, more specifically, the exponential discounting have been the paradigmatic methodology used to measure the preferences on delayed outcomes. However, this model can only be applied to consistent choices in which individuals do not change their preferences when the involved rewards are delayed the same time interval. Unfortunately, this is not the case of several decision scenarios where time is viewed as a subjective variable. The objective of this paper is to formally analyze the consistency of intertemporal choices governed by a discount function, derived from the exponential, where time has been distorted according to certain psychological traits of the subjects involved in the decision-making. More specifically, the different types of decreasing impatience will be characterized by focusing on the distortion derived from the subjective perspective of time. The findings of this research are very relevant in order to explain the time-related behavior of decision-makers in some noteworthy fields such as finance, psychology, marketing or sociology.

Brain response in heavy drinkers during cross-commodity alcohol and money discounting with potentially real rewards: A preliminary study

Background

Alcohol use disorder (AUD) is associated with exaggerated preference for immediate rewards, a candidate endophenotype for use disorders. Addiction symptomology is often well-described by the preference for immediate intoxication over other delayed prosocial rewards. We measured brain activation in AUD-implicated regions during a cross-commodity delay discounting (CCD) task with choices for immediate alcohol and delayed money.

Methods

Heavy drinkers (n=24) experienced a brief intravenous alcohol infusion prime, regained sobriety, then chose between 'One Shot' and delayed money in an adjusting delay CCD task (sober and intoxicated); also during fMRI (sober). Participants also performed a behavioral sensation seeking task and completed self-report inventories of other risk factors. We assessed brain activation to choices representing immediate intoxication versus delayed money rewards in a priori regions of interest defined within the framework of Addictions NeuroImaging Assessment.

Results

Activation to CCD choice versus control trials activated paralimbic and ventral frontal cortical regions, including orbital and medial prefrontal cortex, posterior cingulate/retrosplenial cortex, angular and superior frontal gyri. We detected no differences between immediate or delayed choices. Left medial orbitofrontal cortex activation correlated with alcohol-induced wanting for alcohol; females showed greater activation than males. Behavioral sensation seeking correlated with right nucleus accumbens task engagement.

Conclusions

Alcohol decision-making elicited activation in regions governing reward, introspection, and executive decision-making in heavy drinkers, demonstrating the utility of laboratory tasks designed to better model real-world choice. Our findings suggest that the brain processes subserving immediate and delayed choices are mostly overlapping, even with varied commodities.

Social Influences on Similarity Judgments and Intertemporal Choice

Discounting models are commonly applied to understand intertemporal choices. Similarity models provide an alternative, attribute-based approach where people compare the similarity of reward amounts and time delays for options and decide based on dissimilarity. Knowledge of other people's similarity judgments may affect an individual's similarity judgments, which can in turn affect subsequent intertemporal choices. We investigated the potential effects of social influence across three studies by having participants make similarity judgments and intertemporal choices before and after viewing other people's similarity judgments. We found that participants preferred larger but delayed intertemporal choice options more after they viewed similarity judgments that suggested a preference for larger, later rewards. Additionally, this change in preference seemed to result from a shift in participants' personal similarity judgments for reward amount and time delay pairs to match the social information. Our findings suggest that social information about similarity judgments can shape intertemporal choices, which can potentially be used to help increase people's preferences for options that benefit them in the long term.

Age differences in intertemporal choice among children, adolescents, and adults

When choosing between sooner-smaller and later-larger rewards (i.e., intertemporal choices), adults typically prefer later-larger rewards more often than children. Intertemporal choice preferences have been implicated in various impulsivity-related psychopathologies, making it important to understand the underlying mechanisms not only in terms of how reward magnitude and delay affect choice but also in terms of how these mechanisms develop across age. We administered an intertemporal choice paradigm to 60 children (8-11 years), 79 adolescents (14-16 years), and 60 young adults (18-23 years). The paradigm systematically varied amounts and delays of the available rewards, allowing us to identify mechanisms underlying age-related differences in patience. Compared with young adults, both children and adolescents made fewer later-larger choices. In terms of underlying mechanisms, variation in delays, absolute reward magnitudes, and relative amount differences affected choice in each age group, indicating that children showed sensitivity to the same choice-relevant factors as young adults. Sensitivity to both absolute reward magnitude and relative amount differences showed a further monotonic age-related increase, whereas no change in delay sensitivity occurred. Lastly, adolescents and young adults weakly displayed a present bias (i.e., overvaluing immediate vs. future rewards; nonsignificant and trend, respectively), whereas children showed a nonsignificant but opposite pattern, possibly indicating that specifically dealing with future rewards changed with age. These findings shed light on the underlying mechanisms that contribute to the development of patience. By decomposing overt choices, our results suggest that the age-related increase in patience may be driven specifically by stronger sensitivity to amount differences with age.

Altered delay discounting in neurodegeneration: insight into the underlying mechanisms and perspectives for clinical applications

Steeper delay discounting (i.e., the extent to which future rewards are perceived as less valuable than immediate ones) has been proposed as a transdiagnostic process across different health conditions, in particular psychiatric disorders. Impulsive decision-making is a hallmark of different neurodegenerative conditions but little is known about delay discounting in the domain of neurodegenerative conditions. We reviewed studies on delay discounting in patients with Parkinson's disease (PD) and in patients with dementia (Alzheimer's disease / AD or frontotemporal dementia / FTD). We proposed that delay discounting could be an early marker of the neurodegenerative process. We developed the idea that altered delay discounting is associated with overlapping but distinct neurocognitive mechanisms across neurodegenerative diseases: dopaminergic-related disorders of reward processing in PD, memory/projection deficits due to medial temporal atrophy in AD, modified reward processing due to orbitofrontal atrophy in FTD. Neurodegeneration could provide a framework to decipher the neuropsychological mechanisms of value-based decision-making. Further, delay discounting could become a marker of interest in clinical practice, in particular for differential diagnosis.

The brain stimulation of DLPFC regulates choice preference in intertemporal choice self-other differences

Intertemporal choice requires to make decision by evaluating the value of two options consisting of different times and benefits. The dorsolateral prefrontal cortex (DLPFC) is a key brain region for modulating intertemporal choice. The aim of this study is to investigate the effect of non-invasive brain stimulation over DLPFC on intertemporal choice behavior for self and others. We used transcranial direct current stimulation (tDCS) and continuous theta burst stimulation (cTBS) to stimulate bilateral DLPFC in two experiments respectively. After stimulation, subjects made a choice between a Smaller-Sooner (SS) reward and a Larger-Later (LL) reward in intertemporal choice task. The results showed that cTBS stimulation on the left DLPFC reduced the choice preference for SS reward when individuals made choices for themselves. The cTBS stimulation caused preference difference between choosing for self and parents. But tDCS stimulation had no effect on regulating choice preference. In addition, subjects preferred SS reward for self than strangers. Time-types and monetary difference of rewards affected the choice preference. The presence of immediate time increased the choice preference of SS reward. As the monetary difference increased, the choice proportion of SS reward decreased. Our study demonstrates that brain stimulation on the left DLPFC can regulate choice preference behavior in intertemporal choice.

The effect of social exclusion on intertemporal choice in suicide attempters: A preliminary experimental study

BACKGROUND

Suicide-related theories and a growing body of evidence suggest that suicidal patients may have a tendency toward "short-sightedness"-the preference for immediate gratification when making intertemporal choice-and that social exclusion may exacerbate this tendency in suicidal patients. The present study examined the intertemporal choice performance of suicide attempters under conditions of social exclusion in a sample of affective disorder patients.

METHODS

A total of 64 affective disorder patients (22 non-suicidal patients, 24 single-suicide attempters and 18 multiple-suicide attempters) completed an intertemporal choice task in an exclusion or a non-exclusion condition. Social exclusion was manipulated using the Cyberball paradigm.

RESULTS

Non-suicidal patients and single-suicide attempters both exhibited an exaggerated preference for immediate rewards in the exclusion condition compared with the non-exclusion condition; in contrast, the multiple-suicide attempters appeared relatively indifferent to the social exclusion, exhibiting virtually identical preferences for immediate rewards in both the exclusion and non-exclusion conditions. In addition, the multiple-suicide attempters exhibited an exaggerated preference for immediate rewards compared with non-suicidal patients and single-suicide attempters in the non-exclusion condition, while the three groups did not differ in the exclusion condition.

CONCLUSIONS

Affective disorder patients with a single or no suicide attempts are more short-sighted after being excluded, while those with multiple suicide attempts appeared consistent short-sightedness in both exclusion and non-exclusion conditions. The study provides preliminary evidence of the role of disadvantageous intertemporal choice in the suicidal process. Future research replicate and extend these findings could have implications for suicide prevention and intervention.

Exogeneous testosterone increases sexual impulsivity in heterosexual men

Testosterone has been hypothesized to promote sexual motivation and behavior. However, experimental evidence in healthy humans is sparse and rarely establishes causality. The present study investigated how testosterone affects delay of gratification for sexual rewards. We administered a single dose of testosterone to healthy young males in a double-blind, placebo-controlled, between-participant design (N = 140). Participants underwent a sexual delay discounting task, in which they made a choice between a variable larger-later option (i.e., waiting longer to view a sexual picture for a longer duration) and a smaller-sooner option (i.e., waiting for a fixed shorter period of time to view the same picture for a shorter duration). We found that testosterone administration increased preference for the smaller-sooner option and induced steeper discounting for the delayed option. These findings provide direct experimental evidence that rapid testosterone elevations increase impulsivity for sexual rewards and represent an important step towards a better understanding of the neuroendocrine basis of sexual motivation in humans.

The impact of uncertainty induced by the COVID-19 pandemic on intertemporal choice

The coronavirus disease (COVID-19) pandemic has triggered a strong sense of uncertainty worldwide, which may lead to short-sighted behaviors. This study aimed to examine the impact of uncertainty induced by COVID-19 on intertemporal choice, as well as its underlying mechanisms, by conducting four experiments. Study 1a verified the causal relationship between uncertainty and intertemporal choice by showing that participants who feel more uncertain are more likely to choose smaller and sooner gains. Study 1b further confirmed this finding by conducting field experiments, which improved the ecological validity of the results. Study 2 not only replicated the results of Study 1 but also investigated the mediating role of future orientation between uncertainty and intertemporal choice. In Study 3, all participants experienced high uncertainty by recalling their own experiences related to COVID-19. The results showed that increasing future orientation reduced their preferences for smaller and sooner gains, further confirming the mediating role of future orientation. Overall, these findings indicate that uncertainty may lead to a present orientation, which in turn fosters preferences for immediate gains.

Self-other differences in intertemporal decision making: An eye-tracking investigation

This study investigated how intertemporal choices made for others differed from those made for oneself, and how attention directed to specific attributes of the choice problem contributed to such differences. Moderating effects of components of trait empathy, chronic construal-level, and personal sense of power were examined. Thirty-five participants performed a money choice task where they made choices for themselves and on behalf of an acquaintance, during which their eye movements were tracked. Results showed that lower scores on the fantasy component of empathy predicted decreased delay discounting while making decisions for others, while higher empathic concern favoured less impulsive choices for both self and others. Higher sense of power favoured less impulsive choices for both self and others. While making decisions for others, higher power biased more attention towards the reward attribute of the choice, which in turn predicted less delay discounting. Results are discussed from a construal-level perspective.

A Neuroeconomics Approach to Obesity

Obesity is a heterogeneous condition that is affected by physiological, behavioral, and environmental factors. Value-based decision making is a useful framework for integrating these factors at the individual level. The disciplines of behavioral economics and reinforcement learning provide tools for identifying specific cognitive and motivational processes that may contribute to the development and maintenance of obesity. Neuroeconomics complements these disciplines by studying the neural mechanisms underlying these processes. We surveyed recent literature on individual decision characteristics that are most frequently implicated in obesity: discounting the value of future outcomes, attitudes toward uncertainty, and learning from rewards and punishments. Our survey highlighted both consistent and inconsistent behavioral findings. These findings underscore the need to examine multiple processes within individuals to identify unique behavioral profiles associated with obesity. Such individual characterization will inform future studies on the neurobiology of obesity as well as the design of effective interventions that are individually tailored.

Overweight/Obesity and Time Preference: Evidence from a Survey among Adults in the UK

INTRODUCTION

Overweight and obesity is a global problem incurring substantial health and economic implications. This has also been highlighted by the ongoing COVID-19 pandemic which has disproportionately affected overweight and obese individuals. Most of the interventions have concentrated on promotion of physical activities and healthy eating which may involve current sacrifices for future health gains. The purpose of this study was to explore the relationship between bodyweight and how individuals state they would trade-off immediate income for higher amounts in the future (time preference).

METHODS

An online survey was conducted targeting adults aged >16 years in the UK (England, Northern Ireland, Scotland, and Wales) from January 1, 2016 to July 31, 2016. Using paid online adverts, as well as personal and professional networks for distribution of links to the online survey, the questionnaire asked respondents to report socio-economic and demographic information, height, and weight and to complete a time preference exercise. Data were analysed using descriptive statistics; associations were explored between BMI and respondents' characteristics and time preference using Spearman rank-order correlation and χ2 tests as appropriate. We adopted STROBE guidelines for the reporting of the study.

RESULTS

A total of 561 responses were analysed (female = 293, males = 268). The relationship between time preference and overweight/obesity, using BMI as the measure is highly significant (χ2 = 95.92: p < 0.001). Individuals of normal weight have low time preferences and are more likely to invest in activities in a bid to reap future health benefits. There are also significant relationships between BMI and employment status (χ2 = 37.03; p < 0.001), physical activities (p < 0.0001), income levels (χ2 = 6.68; p < 0.035), family orientation, i.e., with or without children (χ2 = 12.88; p < 0.012), and ethnicity (χ2 = 18.31; p < 0.001). These imply that individuals in employment and with children in their families are less likely to be overweight or obese compared to those who do not. People from black backgrounds are also more likely to be overweight or obese and have higher time preferences compared to people from white backgrounds.

DISCUSSIONS/CONCLUSIONS

People's preventive behaviours today can be predicted by their time preference and this understanding could be vital in improving population's uptake and maintenance of overweight and obesity prevention actions. People who have low time preference are more likely to invest time and resources in physical activities and healthy lifestyles to reap future health benefits hence value utilities-in-anticipation. Public health programmes should therefore use the knowledge of the association between time preference and overweight/obesity to inform designs of intervention programmes.

The effects of cueing episodic future thinking on delay discounting in children, adolescents, and adults

Discounting the value of delayed rewards such that even a relatively small, immediately available reward is preferred to a larger delayed reward is a commonly observed human trait. Children are particularly steep discounters of delayed rewards as evidenced by delay of gratification studies. In recent years, however, a growing literature indicates that cueing individuals to imagine personal future events attenuates their discounting of delayed rewards. The present studies extend this literature by examining whether cueing future thinking promotes patient choices in children and adolescents. In Experiment 1 we found that cueing future thinking had no effect on 8-11-year-olds' (n = 177) delay discounting of either real or hypothetical rewards. In Experiment 2 we found that cueing adolescents (12-14-year-olds, n = 126) and adults (n = 122) to think about personal future events decreased their discounting of delayed rewards relative to three other conditions: a no cue control, an episodic memory condition and a novel 'future other' condition in which individuals imagine future events that might happen to a significant other person in their life. Cueing adults and adolescents to think about personal future events did not however affect how connected they felt to their future selves or their subjective sense of how close future time points felt to them - two constructs that have previously been shown to be related to delay discounting.

Music-induced emotions influence intertemporal decision making

People tend to choose smaller, immediate rewards over larger, delayed rewards. This phenomenon is thought to be associated with emotional engagement. However, few studies have demonstrated the real-time impact of incidental emotions on intertemporal choices. This research investigated the effects of music-induced incidental emotions on intertemporal choices, during which happy or sad music was played simultaneously. We found that music-induced happiness made participants prefer smaller-but-sooner rewards (SS), whereas music-induced sadness made participants prefer larger-but-later rewards (LL). Time perception partially mediated this effect: the greater the perceived temporal difference, the more likely they were to prefer SS. Tempo and mode were then manipulated to disentangle the effects of arousal and mood on intertemporal choices. Only tempo-induced arousal, but not mode-induced mood, affected intertemporal choices. These results suggest the role of arousal in intertemporal decision making and provide evidence in support of equate-to-differentiate theory with regard to the non-compensatory mechanism in intertemporal choices.

Activation patterns of the dorsal medial prefrontal cortex and frontal pole predict individual differences in decision impulsivity

Intertemporal choice refers to decisions that need to weigh different rewards at different time points in the future. Decision impulsivity manifests in the tendency of choosing smaller immediate options rather than larger later ones. Previous studies have suggested that decision impulsivity in intertemporal decision-making shares similar cognitive and neural mechanisms with risky decision-making. The present study theorizes on and examines whether the activation patterns of the dorsal medial prefrontal cortex (DMPFC) and the frontal pole (FP) during the risk-taking "cups task", as captured in the scanner, can predict the delay discounting rate (k) based on an intertemporal decision task performed outside the scanner. To this end, we scanned with functional magnetic resonance imaging (fMRI) techniques a sample of 257 college students (N = 257) while performing the cups task. Univariate analyses showed that activation levels of the DMPFC and the FP were inversely correlated with risk preference, but not with the delay discounting rate k. Multivariate pattern analysis, which can overcome key limitations of the univariate analyses, showed that activation patterns of these two regions predict the delay discounting rate k. These results confirmed the important roles of DMPFC and FP in decision impulsivity and the utility of using multivariate pattern analysis with fMRI data involving decision making tasks.

Neuroanatomical and functional substrates of the greed personality trait

Greedy individuals often exhibit more impulsive decision-making and short-sighted behaviors. It has been assumed that altered reward circuitry and prospection network is associated with greed personality trait (GPT). In this study, we first explored the morphological characteristics (i.e., gray matter volume; GMV) of GPT combined with univariate and multivariate pattern analysis (MVPA) approaches. Second, we adopted a revised version of inter-temporal choice task and independently manipulated the amount and delay time of future rewards. Using brain-imaging design, reward- and prospection-related brain activations were assessed and their associations with GPT were further examined. The MVPA results showed that GPT was associated with the GMVs in the right lateral frontal pole cortex, left ventromedial prefrontal cortex, right lateral occipital cortex, and right occipital pole. Additionally, we observed that the amount-relevant brain activations (responding to reward circuitry) in the lateral orbitofrontal cortex were negatively associated with individual's variability in GPT scores, whereas the delay time-relevant brain activations (responding to prospection network system) in the dorsolateral prefrontal cortex, dorsomedial prefrontal cortex, superior parietal lobule, and anterior cingulate cortex were positively associated with individual's variability in GPT scores. These findings not only provide novel insights into the neuroanatomical substrates underlying the human dispositional greed, but also suggest the critical roles of reward and prospection processing on the greed.

Does excessive use of smartphones and apps make us more impulsive? An approach from behavioural economics

Purpose

Problematic smartphone use has been associated with negative effects in work and school environments. This study proposes the application of a behavioural economics perspective to establish whether heavy smartphone users show a tendency to devalue the consequences of their behaviour in the long term. To address this proposition, the study sought to establish how an objective measurement of usage time of smartphones and apps might help to predict, firstly, participants’ choice behaviour and, secondly, their perceived dependence levels.

Design/methodology/approach

An objective measurement of the usage time of smartphones and apps was conducted over four weeks (N = 560 data points), and a computer-based intertemporal choice task and the Spanish version of the Smartphone Addiction Inventory (SPAI) were applied. The participants were twenty undergraduate college students.

Findings

Although the usage time of devices and apps failed to predict the choice behaviour, a correlation was found between the total usage time of smartphones and WhatsApp and Facebook apps and users’ dependence level. On the other hand, dependence had a positive effect on the average selection of the impulsive choice.

Originality/value

This paper proposes the application of a behavioural economics perspective to explore the relationship between objectively measured usage time of smartphone and apps, choice behaviours in an intertemporal task and users’ perceived dependence levels. This allows us to consider an alternative to the traditional psychiatric approach in an environment of increasing access to and use of mobile digital platforms.

Temporal discounting and smoking cessation: choice consistency predicts nicotine abstinence in treatment-seeking smokers

INTRODUCTION

Smokers discount delayed rewards steeper than non-smokers or ex-smokers, possibly due to neuropharmacological effects of tobacco on brain circuitry, or lower abstinence rates in smokers with steep discounting. To delineate both theories from each other, we tested if temporal discounting, choice inconsistency, and related brain activity in treatment-seeking smokers (1) are higher compared to non-smokers, (2) decrease after smoking cessation, and (3) predict relapse.

METHODS

At T1, 44 dependent smokers, 29 non-smokers, and 30 occasional smokers underwent fMRI while performing an intertemporal choice task. Smokers were measured before and 21 days after cessation if abstinent from nicotine. In total, 27 smokers, 28 non-smokers, and 29 occasional smokers were scanned again at T2. Discounting rate k and inconsistency var(k) were estimated with Bayesian analysis.

RESULTS

First, k and var(k) in smokers in treatment were not higher than in non-smokers or occasional smokers. Second, neither k nor var(k) changed after smoking cessation. Third, k did not predict relapse, but high var(k) was associated with relapse during treatment and over 6 months. Brain activity in valuation and decision networks did not significantly differ between groups and conditions.

CONCLUSION

Our data from treatment-seeking smokers do not support the pharmacological hypothesis of pronounced reversible changes in discounting behavior and brain activity, possibly due to limited power. Behavioral data rather suggest that differences between current and ex-smokers might be due to selection. The association of choice consistency and treatment outcome possibly links consistent intertemporal decisions to remaining abstinent.

The improving sequence effect on monetary sequences

Experimental studies reveal a preference for improving income sequences, challenging the axioms of the discounted utility model, such as the present value maximization principle. Through an experiment, we test the existence of this anomaly on short and long-term income sequences, by confirming previous experimental evidence. Although the participants are aware of the present value maximization, they select improving sequences of income mainly to cover their future spending needs, to feel motivation at work, and to receive a signal of success and status. In order to include this sequence effect in a mathematical valuation model, we propose an alternative model to value sequences which outperforms the traditional discounting model by fitting the present value with the preferences of the participants.

Future preferences and prospection of future of outcomes: Independent yet specific associations with attention-deficit/hyperactivity disorder

INTRODUCTION

Symptoms of attention-deficit hyperactivity disorder (ADHD) and conduct problems have been associated with heightened temporal discounting of reward value resulting in a preference for immediate over delayed outcomes. We examined the cross-sectional relationship between future preference (including intertemporal choice) and prospection (the ability to bring to mind and imagine the experience of future personally-relevant events and outcomes) in adolescents with a range of ADHD symptoms and aggressive behaviour.

METHODS

A combination of behavioural tasks and self-reports measured intertemporal decision making, individual differences in preference for future outcomes and experience of prospection in a convenience sample of English adolescents aged 11-17 (n = 64, 43.8% males). Parents rated symptoms of ADHD and aggression.

RESULTS

& Conclusions: Factor analysis identified two factors: "Future Preference" and "Prospection". Significant negative bivariate correlations were found between ADHD and the scores of both factors and between aggression and Future Preference. A path model confirmed the independent significant association of ADHD with both factors but not with aggression. There was no evidence that Prospection was associated with Future Preference or that it reduced the associations between ADHD symptoms and Future Preference. These results provide further evidence that ADHD is associated with a tendency to prefer immediate over future outcomes. The same association with aggression seemed to be driven by the overlap with ADHD symptoms. We provide some of the first evidence that individuals with high ADHD symptoms have difficulty in prospecting about future episodes. However, this is unrelated to their preference for future outcomes.

Neural and behavioral correlates of episodic memory are associated with temporal discounting in older adults

When facing decisions involving trade-offs between smaller, sooner and larger, delayed rewards, people tend to discount the value of future rewards. There are substantial individual differences in this tendency toward temporal discounting, however. One neurocognitive system that may underlie these individual differences is episodic memory, given the overlap in the neural circuitry involved in imagining the future and remembering the past. Here we tested this hypothesis in older adults, including both those that were cognitively normal and those with amnestic mild cognitive impairment (MCI). We found that performance on neuropsychological measures of episodic memory retrieval was associated with temporal discounting, such that people with better memory discounted delayed rewards less. This relationship was specific to episodic memory and temporal discounting, since executive function (another cognitive ability) was unrelated to temporal discounting, and episodic memory was unrelated to risk tolerance (another decision-making preference). We also examined cortical thickness and volume in medial temporal lobe regions critical for episodic memory. Entorhinal cortical thickness was associated with reduced temporal discounting, with episodic memory performance partially mediating this association. The inclusion of MCI participants was critical to revealing these associations between episodic memory and entorhinal cortical thickness and temporal discounting. These effects were larger in the MCI group, reduced after controlling for MCI status, and statistically significant only when including MCI participants in analyses. Overall, these findings suggest that individual differences in temporal discounting are driven by episodic memory function, and that a decline in medial temporal lobe structural integrity may impact temporal discounting.

Is it time? Episodic imagining and the discounting of delayed and probabilistic rewards in young and older adults

Remembering and imagining specific, personal experiences can help shape our decisions. For example, cues to imagine future events can reduce delay discounting (i.e., increase the subjective value of future rewards). It is not known, however, whether such cues can also modulate other forms of reward discounting, such as probability discounting (i.e., the decrease in the subjective value of a possible reward as the odds against its occurrence increase). In addition, it is unclear whether there are age-related differences in the effects of cueing on either delay or probability discounting. Accordingly, young and older adult participants were administered delay and probability discounting tasks both with and without cues to imagine specific, personally meaningful events. As expected, cued episodic imagining decreased the discounting of delayed rewards. Notably, however, this effect was significantly less pronounced in older adults. In contrast to the effects of cueing on delay discounting, personally relevant event cues had little or no effect on the discounting of probabilistic rewards in either young or older adults; Bayesian analysis revealed compelling support for the null hypothesis that event cues do not modulate the subjective value of probabilistic rewards. In sum, imagining future events appears only to affect decisions involving delayed rewards. Although the cueing effect is smaller in older adults, nevertheless, it likely contributes to how adults of all ages evaluate delayed rewards and thus, it is, in fact, about time.

Dogs wait longer for better rewards than wolves in a delay of gratification task: but why?

Self-control has been shown to be linked with being cooperative and successful in humans and with the g-factor in chimpanzees. As such, it is likely to play an important role in all forms of problem-solving. Self-control, however, does not just vary across individuals but seems also to be dependent on the ecological niche of the respective species. With dogs having been selected to live in the human environment, several domestication hypotheses have predicted that dogs are better at self-control and thus more tolerant of longer delays than wolves. Here we set out to test this prediction by comparing dogs' and wolves' self-control abilities using a delay of gratification task where the animals had to wait for a predefined delay duration to exchange a low-quality reward for a high-quality reward. We found that in our task, dogs outperformed the wolves waiting an average of 66 s vs. 24 s in the wolves. Food quality did not influence how long the animals waited for the better reward. However, dogs performed overall better in motivation trials than the wolves, although the dogs' performance in those trials was dependent on the duration of the delays in the test trials, whereas this was not the case for the wolves. Overall, the data suggest that selection by humans for traits influencing self-control rather than ecological factors might drive self-control abilities in wolves and dogs. However, several other factors might contribute or explain the observed differences including the presence of the humans, which might have inhibited the dogs more than the wolves, lower motivation of the wolves compared to the dogs to participate in the task and/or wolves having a better understanding of the task contingencies. These possible explanations need further exploration.

Pubertal testosterone correlates with adolescent impatience and dorsal striatal activity

Recent self-report and behavioral studies have demonstrated that pubertal testosterone is related to an increase in risky and impulsive behavior. Yet, the mechanisms underlying such a relationship are poorly understood. Findings from both human and rodent studies point towards distinct striatal pathways including the ventral and dorsal striatum as key target regions for pubertal hormones. In this study we investigated task-related impatience of boys between 10 and 15 years of age (N = 75), using an intertemporal choice task combined with measures of functional magnetic resonance imaging and hormonal assessment. Increased levels of testosterone were associated with a greater response bias towards choosing the smaller sooner option. Furthermore, our results show that testosterone specifically modulates the dorsal, not ventral, striatal pathway. These results provide novel insights into our understanding of adolescent impulsive and risky behaviors and how pubertal hormones are related to neural processes.

Uncommitted Commitment: Behavioral Strategy to Prevent Preference Reversals

When both smaller-sooner (SS) and larger-later (LL) rewards are temporally distal, individuals frequently prefer the LL. However, because both outcomes become proximal, individuals frequently switch to preferring the SS. These preference reversals are predicted by hyperbolic delay discounting, and may model the essential challenge of self-control. Using smokers, a population known to have high rates of delay discounting, and thus more vulnerable to preference reversals, this pilot study sought to examine soft commitment as a strategy that may prevent preference reversals. Eleven smokers were assigned to an experimental commitment condition, operationalized as 3 weeks of daily commitment trials indicating preference between an SS and LL. Ten smokers were assigned to a control commitment condition. These 3 weeks were followed by 8 days of daily choice trials indicating preference between an impending SS and LL, for both experimental and control conditions. Though no overall difference of preference was observed between groups during the choice trials, hierarchical linear modeling revealed a decrease in preference for the LL over time by the control group (e.g., increasing trend of preference reversals) but no changes by the experimental group. This pilot study provides an initial indication that soft commitment can facilitate choice persistence and prevent preference reversals.

Preferences for Temporal Sequences of Real Outcomes Differ Across Domains but do not Vary by Age

OBJECTIVES

People's preferences for temporal sequences of events have implications for life-long health and well-being. Prior research suggests that other aspects of intertemporal choice vary by age, but evidence for age differences in sequence-preferences is limited and inconclusive. In response, the present research examined age differences in sequence-preferences for real outcomes administered in a controlled laboratory setting.

METHODS

A pilot study examined sequence-preferences for aversive electrodermal shocks in 30 younger and 30 older adults. The main study examined sequence-preferences for electrodermal shocks, physical effort, and monetary gambles in an adult life-span sample (N = 120). It also examined emotional and physiological responses to sequences as well as underlying mechanisms including time perception and emotion-regulation.

RESULTS

There were no significant age differences in sequence-preferences in either of the studies, and there were no age differences in responses to sequences in the main study. Instead, there was a domain effect with participants preferring decreasing sequences for shocks and mixed sequences for effort and money.

DISCUSSION

After considering potential methodological limitations, theoretical contributions and implications for real-life decisions are discussed.

Age Differences in Intertemporal Choice: The Role of Task Type, Outcome Characteristics, and Covariates

OBJECTIVES

Prior research has revealed age differences in the preferred timing of monetary outcomes, but results are inconsistent across studies. The present study examined the role of task type, outcome characteristics, and a range of theoretically implicated covariates that may contribute to variations in age effects.

METHOD

Two types of intertemporal choice paradigms (temporal discounting and sequence construction) were administered to a diverse life-span sample (n = 287, aged 18-87). The design experimentally manipulated outcome delay (months vs years), amount (hundreds vs thousands), and valence (gain vs loss) while statistically controlling for a range of potential covariates including demographics, affect, personality, time perspective, subjective health, and numeracy.

RESULTS

In the temporal discounting task, no significant age differences were observed and this pattern did not differ by outcome delay, amount, or valence. In the sequence-construction task, age was associated with a preference for sequences of decreasing impact in the gain condition but not in the loss condition, whereas outcome delay and amount did not moderate age effects. Age patterns in discounting and sequences preferences remained unchanged after controlling for covariates.

DISCUSSION

These findings converge with prior studies reporting weak or null effects of age in temporal discounting tasks and suggest that inconsistent results are not due to variations in outcome valence, delay, or amount across studies. Findings also add to the scarce evidence for age differences sequence-preferences. After discussing methodological limitations, we consider implications for future research and practice.

Are future selves treated like others? Comparing determinants and levels of intrapersonal and interpersonal allocations

People often make tradeoffs between current and future benefits. Some research frameworks suggest that people treat the future self as if it were another person, subordinating future needs to current ones just as they might subordinate others' needs to their own. Although people make similar choices for future selves and others in some contexts, it remains unclear whether these behaviors are governed by the same decision policies. So, we identify and compare the unique influence of four relevant factors (need, deservingness, liking, and similarity) on monetary decisions in both the interpersonal and intrapersonal domains. Do people treat the future self and others similarly? Yes and no. Yes, because the influence of these factors on allocations is similar for both types of targets. No, because monetary allocations to the future self are consistently higher than allocations to others. Although the future self is treated like others in some ways, important differences remain that are not fully captured by this analogy.

The regional homogeneity patterns of the dorsal medial prefrontal cortex predict individual differences in decision impulsivity

Intertemporal choice refers to the process of making decisions by weighing short- and long-term benefits and costs. On average people prefer immediate rewards over delayed rewards with larger amounts, which is a form of decision impulsivity. Based on previous research showing the importance of the dorsal medial prefrontal cortex (DMPFC) in decision impulsivity, the present study examined whether regional homogeneity (ReHo) patterns in DMPFC were associated with individual differences in intertemporal choices. Two cohorts of college students (N = 239 and N = 227, respectively) were recruited and resting-state data were collected. Results from both univariate and multivariate pattern analyses of the two cohorts consistently showed that ReHo patterns in the DMPFC were associated with the delay discounting rate (i.e., log k). These results further support the important role of DMPFC in intertemporal choice and have potential practical implications for decision making in our daily life and at the level of national policies as well as for the treatment of clinical populations with decision impulsivity (e.g., gamblers, individuals with substance use disorders).

Variable time preference

We re-examine behavioral patterns of intertemporal choice with recognition that time preferences may be inherently variable, focusing in particular on the explanatory power of an exponential discounting model with variable discount factors - the variable exponential model. We provide analytical results showing that this model can generate systematically different choice patterns from an exponential discounting model with a fixed discount factor. The variable exponential model accounts for the common behavioral pattern of decreasing impatience, which is typically attributed to hyperbolic discounting. The variable exponential model also generates violations of strong stochastic transitivity in choices involving intertemporal dominance. We present the results of two experiments designed to evaluate the variable exponential model in terms of quantitative fit to individual-level choice data. Data from these experiments reveal that allowing for a variable discount factor significantly improves the fit of the exponential model, and that a variable exponential model provides a better account of individual-level choice probabilities than hyperbolic discounting models. In a third experiment we find evidence of strong stochastic transitivity violations when intertemporal dominance is involved, in accordance with the variable exponential model. Overall, our analytical and experimental results indicate that exponential discounting can explain intertemporal choice behavior that was supposed to be beyond its descriptive scope if the discount factor is permitted to vary at random. Our results also highlight the importance of allowing for different sources of randomness in choice modeling.

Decoy effects in intertemporal and probabilistic choices the role of time pressure, immediacy, and certainty

A decoy is an irrelevant option that, when added to a binary choice, is not selected but nonetheless alters the subjects' preferences, systematically biasing towards its target. The decoy effect, also known as attraction effect, is considered an anomaly of rational decision-making, albeit its applicability to real-life choices outside of laboratory settings has been challenged. In particular, when decoys have been studied in choices between outcomes occurring at different points in time, i.e. intertemporal choices, or with different probabilities of realizing their utility, i.e. probabilistic choices, results were mixed: sometimes decoys are impactful, sometimes they are not, and they seem to be more effective in biasing towards, respectively, larger-and-later and larger-and-riskier outcomes, rather than towards sooner-and-smaller or sooner-and-safer rewards. We suggest that this puzzling set of results can be clarified by focusing on two important influencing factors: time pressure and immediacy/certainty. Moreover, we argue that decoy effects constitute an excellent testbed to assess similarities and differences between intertemporal choice and risky decision-making, which constitutes another open issue in the study of human choice. Two studies are presented to support these claims. In Study 1 (N = 92), we demonstrate that asymmetrically dominated decoys influence both intertemporal choice and risky decision-making only in the absence of time pressure, since otherwise the comparative process required for the decoy to have an impact cannot occur, consistently with predictions made by connectionist models of decision. In Study 2 (N = 53), we show that, when the smaller option is no longer presented as immediate/certain (but rather as sooner/safer), the impact of decoys becomes symmetrical - that is, they can prompt subjects to become either more future-oriented/risk-prone or more present-oriented/risk-averse. We conclude by discussing the implications of these findings for our understanding of the multifaceted role of time and chance in decision making.

Time orientation mediates the link between hunger and hedonic choices across domains

This study investigated the link between hunger and individuals' inclination to make hedonic choices in several distinct consumption domains. Participants made a set of binary choices between hedonic and utilitarian items, both from the food domain (for example, between chocolate and carrots) and from domains unassociated with food (for instance, between an apartment with a nice view and an apartment close to work). Next, participants indicated their hunger level, after which they replied to items measuring time orientation. The results revealed that hunger (vs. satiation) increased participants' proclivity to make hedonic choices across domains. This effect was moderated by the domain specificity of the items to be consumed and was mediated by participants' time orientation. Thus, although hunger resulted in a generalized pleasure-seeking propensity, leading to more hedonic choices regarding virtually anything, hungry (vs. satiated) participants showed a particularly powerful increase in their desire to acquire hedonic food (vs. non-food) items, and this effect was driven by a shift in their time orientation, with a more prominent focus on present pleasures. The article has important implications for time-specific marketing messages of hedonic consumer goods and offers creative ways to counteract shortsighted consumer choices that may be used to promote public health.

Predicting similarity judgments in intertemporal choice with machine learning

Similarity models of intertemporal choice are heuristics that choose based on similarity judgments of the reward amounts and time delays. Yet, we do not know how these judgments are made. Here, we use machine-learning algorithms to assess what factors predict similarity judgments and whether decision trees capture the judgment outcomes and process. We find that combining small and large values into numerical differences and ratios and arranging them in tree-like structures can predict both similarity judgments and response times. Our results suggest that we can use machine learning to not only model decision outcomes but also model how decisions are made. Revealing how people make these important judgments may be useful in developing interventions to help them make better decisions.

Acute stress and altruism in younger and older adults

Recent studies of aging and decision making suggests that altruism increases with age. It is unclear, however, whether this pattern holds when choices are made under stress, as is often the case in real-world scenarios. The current study used an intertemporal choice task in which younger and older adults received a financial endowment before making a series of consequential intertemporal decisions involving gains, losses and charitable donations. Preceding the choice task, participants were exposed to a laboratory stressor. Physiological stress reactivity was a predictor of altruistic decision making in younger adults, such that individuals with higher stress reactivity made more generous choices. Older adults showed higher altruism than younger adults overall, with altruism unrelated to stress reactivity in older adults. These findings are consistent with an age-related change in the mechanisms underlying altruistic behavior.

Joint modeling of reaction times and choice improves parameter identifiability in reinforcement learning models

BACKGROUND

Reinforcement learning models provide excellent descriptions of learning in multiple species across a variety of tasks. Many researchers are interested in relating parameters of reinforcement learning models to neural measures, psychological variables or experimental manipulations. We demonstrate that parameter identification is difficult because a range of parameter values provide approximately equal quality fits to data. This identification problem has a large impact on power: we show that a researcher who wants to detect a medium sized correlation (r = .3) with 80% power between a variable and learning rate must collect 60% more subjects than specified by a typical power analysis in order to account for the noise introduced by model fitting.

NEW METHOD

We derive a Bayesian optimal model fitting technique that takes advantage of information contained in choices and reaction times to constrain parameter estimates.

RESULTS

We show using simulation and empirical data that this method substantially improves the ability to recover learning rates.

COMPARISON WITH EXISTING METHODS

We compare this method against the use of Bayesian priors. We show in simulations that the combined use of Bayesian priors and reaction times confers the highest parameter identifiability. However, in real data where the priors may have been misspecified, the use of Bayesian priors interferes with the ability of reaction time data to improve parameter identifiability.

CONCLUSIONS

We present a simple technique that takes advantage of readily available data to substantially improve the quality of inferences that can be drawn from parameters of reinforcement learning models.

Spending too little in hard times

People's decisions to consume and save resources are critical to their wellbeing. Previous experiments find that people typically spend too much because of how they discount the future. We propose that people's motive to preserve their savings can instead cause them to spend too little in hard times. We design an economic game in which participants can store resources for the future to survive in a harsh environment. A player's income is uncertain and consumption yields diminishing returns within each day, creating tradeoffs between spending and saving. We compare participants' decisions to a heuristic that performed best in simulations. We find that participants spent too much after windfalls in income, consistent with previous research, but they also spent too little after downturns, supporting the resource preservation hypothesis. In Experiment 2, we find that by varying the income stream, the downturn effect can be isolated from the windfall effect. In Experiments 3-4, we find the same downturn effect in games with financial and political themes.

Pattern classification differentiates decision of intertemporal choices using multi-voxel pattern analysis

In daily life, individuals frequently make trade-offs between the small-but-immediate benefits and large-but-delayed profits. This type of decision is known as intertemporal choice. Previous studies have uncovered the neurobiological mechanism of the intertemporal choice, but it still remains unclear how the patterns of brain activity predict the decisions of intertemporal choices. To fill this gap, we used functional magnetic resonance imaging (fMRI), in conjunction with the machine learning technique of multi-voxel pattern analysis (MVPA), to ascertain the predictive capability of the neuronal pattern for classifying individuals' intertemporal decisions across two independent samples. To further probe how this neuronal pattern worked in predicting individual intertemporal decision, we drew on the Power Atlas to examine the accuracies of classification within each regional mask as well. Classification findings showed that the pattern of neuronal activity over the whole-brain can correctly classify the accuracies of individual decisions up to 84.3%. Encouragingly, further analysis shows that the neuronal information encoded in three brain functional networks can predict individuals' decisions with significant discriminative power in cross-samples, namely the valuation network (e.g., striatum), the cognitive control network (e.g., dorsolateral prefrontal cortex) and the episodic prospection network (e.g., amygdala, parahippocampus gyrus, insula). Collectively, these findings advance our comprehension of the neuronal mechanism of human intertemporal decisions, and substantially reshape our understanding for this cardinal behaviour from behavioural-brain scheme to brain-behavioural configuration.

Pairing neutral cues with alcohol intoxication: new findings in executive and attention networks

RATIONALE

Alcohol-associated stimuli capture attention, yet drinkers differ in the precise stimuli that become paired with intoxication.

OBJECTIVES

Extending our prior work to examine the influence of alcoholism risk factors, we paired abstract visual stimuli with intravenous alcohol delivered covertly and examined brain responses to these Pavlovian-conditioned stimuli in fMRI when subjects were not intoxicated.

METHODS

Sixty healthy drinkers performed task-irrelevant alcohol conditioning that presented geometric shapes as conditioned stimuli. Shapes were paired with a rapidly rising alcohol limb (conditioned stimulus; CS+) using intravenous alcohol infusion targeting a final peak breath alcohol concentration of 0.045 g/dL or saline (CS-) infusion at matched rates. On day 2, subjects performed monetary delay discounting outside the scanner to assess delay tolerance and then underwent event-related fMRI while performing the same task with CS+, CS-, and an irrelevant symbol.

RESULTS

CS+ elicited stronger activation than CS- in frontoparietal executive/attention and orbitofrontal reward-associated networks. Risk factors including family history, recent drinking, sex, and age of drinking onset did not relate to the [CS+ > CS-] activation. Delay-tolerant choice and [CS+ > CS-] activation in right inferior parietal cortex were positively related.

CONCLUSIONS

Networks governing executive attention and reward showed enhanced responses to stimuli experimentally paired with intoxication, with the right parietal cortex implicated in both alcohol cue pairing and intertemporal choice. While different from our previous study results in 14 men, we believe this paradigm in a large sample of male and female drinkers offers novel insights into Pavlovian processes less affected by idiosyncratic drug associations.

Separate Neural Networks for Gains and Losses in Intertemporal Choice

An important and unresolved question is how human brain regions process information and interact with each other in intertemporal choice related to gains and losses. Using psychophysiological interaction and dynamic causal modeling analyses, we investigated the functional interactions between regions involved in the decision-making process while participants performed temporal discounting tasks in both the gains and losses domains. We found two distinct intrinsic valuation systems underlying temporal discounting in the gains and losses domains: gains were specifically evaluated in the medial regions, including the medial prefrontal and orbitofrontal cortices, and losses were evaluated in the lateral dorsolateral prefrontal cortex. In addition, immediate reward or punishment was found to modulate the functional interactions between the dorsolateral prefrontal cortex and distinct regions in both the gains and losses domains: in the gains domain, the mesolimbic regions; in the losses domain, the medial prefrontal cortex, anterior cingulate cortex, and insula. These findings suggest that intertemporal choice of gains and losses might involve distinct valuation systems, and more importantly, separate neural interactions may implement the intertemporal choices of gains and losses. These findings may provide a new biological perspective for understanding the neural mechanisms underlying intertemporal choice of gains and losses.

Value-based decision-making battery: A Bayesian adaptive approach to assess impulsive and risky behavior

Using simple mathematical models of choice behavior, we present a Bayesian adaptive algorithm to assess measures of impulsive and risky decision making. Practically, these measures are characterized by discounting rates and are used to classify individuals or population groups, to distinguish unhealthy behavior, and to predict developmental courses. However, a constant demand for improved tools to assess these constructs remains unanswered. The algorithm is based on trial-by-trial observations. At each step, a choice is made between immediate (certain) and delayed (risky) options. Then the current parameter estimates are updated by the likelihood of observing the choice, and the next offers are provided from the indifference point, so that they will acquire the most informative data based on the current parameter estimates. The procedure continues for a certain number of trials in order to reach a stable estimation. The algorithm is discussed in detail for the delay discounting case, and results from decision making under risk for gains, losses, and mixed prospects are also provided. Simulated experiments using prescribed parameter values were performed to justify the algorithm in terms of the reproducibility of its parameters for individual assessments, and to test the reliability of the estimation procedure in a group-level analysis. The algorithm was implemented as an experimental battery to measure temporal and probability discounting rates together with loss aversion, and was tested on a healthy participant sample.

How Cross-Linguistic Differences in the Grammaticalization of Future Time Reference Influence Intertemporal Choices

According to Chen's (2013) Linguistic Savings Hypothesis (LSH), our native language affects our economic behavior. We present three studies investigating how cross-linguistic differences in the grammaticalization of future-time reference (FTR) affect intertemporal choices. In a series of decision scenarios about finance and health issues, we let speakers of altogether five languages that represent FTR with increasing strength, that is, Chinese, German, Danish, Spanish, and English, choose between hypothetical sooner-smaller and later-larger reward options. While the LSH predicts a present-bias that increases with FTR-strength, our decision makers preferred later-larger options and this future-bias increased with FTR-strength. In multiple regressions, the FTR-strength effect persisted when controlled for socioeconomic and cultural differences. We discuss why our findings deviate from the LSH and ask in how far the FTR-strength effect represents a habitual constitution of linguistic relativity or an instance of online decision framing.

Choosing the right delay-discounting task: Completion times and rates of nonsystematic data

A variety of delay discounting tasks are widely used in human studies designed to quantify the degree to which individuals discount the value of delayed rewards. It is currently unknown which task(s) yields the largest proportion of valid and systematic data using standard criteria (Johnson & Bickel, 2008). The goal of this study was to compare three delay-discounting tasks on task duration and amount of valid and systematic data produced. In Experiment 1, 180 college students completed one of three tasks online (fixed alternatives, titrating, or visual analogue scale [VAS]). Invalid and nonsystematic data, identified using standard criteria, were most prevalent with the VAS (47.3% of participants). The other tasks produced more (and similar amounts of) valid and systematic data, but required more time to complete than the VAS. Viewing systematic data as more important than completion times, Experiment 2 (n = 153 college students) sought to reduce the amount of invalid datasets in the fixed-alternatives task, and compare amounts of nonsystematic data with the titrating task. Completion times were superior in the titrating task, which produced modestly more systematic data than the fixed-alternatives task. Causes of invalid and nonsystematic data are discussed, as are methods for reducing data exclusion.

Dynamic cognitive models of intertemporal choice

Traditionally, descriptive accounts of intertemporal choice have relied on static and deterministic models that assume alternative-wise processing of the options. Recent research, by contrast, has highlighted the dynamic and probabilistic nature of intertemporal choice and provided support for attribute-wise processing. Currently, dynamic models of intertemporal choice-which account for both the resulting choice and the time course over which the construction of a choice develops-rely exclusively on the framework of evidence accumulation. In this article, we develop and rigorously compare several candidate schemes for dynamic models of intertemporal choice. Specifically, we consider an existing dynamic modeling scheme based on decision field theory and develop two novel modeling schemes-one assuming lexicographic, noncompensatory processing, and the other built on the classical concepts of random utility in economics and discrimination thresholds in psychophysics. We show that all three modeling schemes can accommodate key behavioral regularities in intertemporal choice. When empirical choice and response time data were fit simultaneously, the models built on random utility and discrimination thresholds performed best. The results also indicated substantial individual differences in the dynamics underlying intertemporal choice. Finally, model recovery analyses demonstrated the benefits of including both choice and response time data for more accurate model selection on the individual level. The present work shows how the classical concept of random utility can be extended to incorporate response dynamics in intertemporal choice. Moreover, the results suggest that this approach offers a successful alternative to the dominating evidence accumulation approach when modeling the dynamics of decision making.

The effect of hydrocortisone administration on intertemporal choice

Intertemporal choices - decisions involving trade-offs of outcomes at different points in time - are often made under stress. Stress activates the hypothalamic-pituitary-adrenal (HPA) axis, resulting in the release of corticosteroids. Recent studies provide evidence that corticosteroids can induce rapid non-genomic effects focused on immediate resolution of the stressful situation, followed by slower genomic effects focused on long-term recovery after stress. It remains unknown, however, how corticosteroids affect intertemporal choice. We randomly assigned healthy men to receive either 10 mg hydrocortisone or a placebo before measuring intertemporal choice. To target time-dependent effects, hydrocortisone was administered either 195 or 15 min before choice elicitation, while a placebo was administered at the other timepoint, in a double-blind design. Intertemporal choices were elicited by offering subjects decisions between small rewards available sooner vs. large rewards available later. We demonstrate a time-dependent effect of hydrocortisone administration on intertemporal choice: when tested 15 min after hydrocortisone administration, subjects showed a strongly increased preference for the small, soon reward over the larger, delayed reward. In contrast, this effect was not found when testing occurred 195 min after hydrocortisone administration. Together, these results suggest that the physiological effects of acute, but not delayed, stress may increase temporal discounting.

Effect of Motion Perception on Intertemporal Choice Is Associated With the Altered Time Perception

Intertemporal choice refers to the choice between receiving a small immediate reward or a large delayed one. Previous studies have indicated that time perception plays a critical role in the intertemporal choice, and it could be affected by the features of the target stimulus in the time reproduction task, such as speed of movement and state of motion. However, there is no evidence about whether backward or forward motion perception could alter the intertemporal choice. Thus, in our current study, 29 participants were asked to perform two tasks in a random order. One was the intertemporal choice task after viewing videos containing moving elements with forward/backward directions as well as stationary ones, and another was the time perception task. We found that the discounting rate in intertemporal choice was significantly larger in backward motion condition than in both forward motion and stationary conditions, indicating that backward motion perception made participants more myopic (specifically, more likely to choose the smaller immediate reward instead of the large delayed one) during their decision-makings. Meanwhile, participants overestimated the temporal duration in a time perception task in backward motion condition compared to the other two conditions. Furthermore, the Pearson's correlation analysis showed that the changes of the intertemporal choice induced by backward motion perception could be associated with the altered time perception. As far as we know, we provide the first evidence on influence of motion perception on the intertemporal choice as well as its possible cognitive correlates, which extend previous studies on cognitive basis of the intertemporal choices.

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.

Choice between delayed food and immediate opioids in rats: treatment effects and individual differences

RATIONALE

Addiction involves maladaptive choice behavior in which immediate drug effects are valued more than delayed nondrug rewards.

OBJECTIVES AND METHODS

To model this behavior and extend our earlier work with the prescription opioid oxycodone, we allowed rats to choose between immediate intravenous delivery of the short-acting opioid remifentanil and delayed delivery of highly palatable food pellets. Treatment drugs were tested on a baseline where remifentanil was preferred over food.

RESULTS

Treatment with a high dose of the opioid antagonist naltrexone decreased but did not reverse the preference for remifentanil. Treatment with the serotonin 5-HT_2C agonist lorcaserin decreased remifentanil and food self-administration nonselectively. Across conditions in which the alternative to delayed food was either a moderate dose of oxycodone, a moderate or high dose of remifentanil, a smaller more immediate delivery of food, or timeout with no primary reinforcement, choice was determined by both the length of the delay and the nature of the alternative option. Delayed food was discounted most steeply when the alternative was a high dose of remifentanil, which was preferred over food when food was delayed by 30 s or more. Within-subject comparisons showed no evidence for trait-like impulsivity or sensitivity to delay across these conditions.

CONCLUSIONS

Choice was determined more by the current contingencies of reinforcement than by innate individual differences. This finding suggests that people might develop steep delay-discounting functions because of the contingencies in their environment, and it supports the use of contingency management to enhance the relative value of delayed nondrug reinforcers.

Decline of prefrontal cortical-mediated executive functions but attenuated delay discounting in aged Fischer 344 × brown Norway hybrid rats

Despite the fact that prefrontal cortex (PFC) function declines with age, aged individuals generally show an enhanced ability to delay gratification, as evident by less discounting of delayed rewards in intertemporal choice tasks. The present study was designed to evaluate relationships between 2 aspects of PFC-dependent cognition (working memory and cognitive flexibility) and intertemporal choice in young (6 months) and aged (24 months) Fischer 344 × brown Norway F1 hybrid rats. Rats were also evaluated for motivation to earn rewards using a progressive ratio task. As previously reported, aged rats showed attenuated discounting of delayed rewards, impaired working memory, and impaired cognitive flexibility compared with young. Among aged rats, greater choice of delayed reward was associated with preserved working memory, impaired cognitive flexibility, and less motivation to work for food. These relationships suggest that age-related changes in PFC and incentive motivation contribute to variance in intertemporal choice within the aged population. Cognitive impairments mediated by PFC are unlikely, however, to fully account for the enhanced ability to delay gratification that accompanies aging.