Delay discounting and intelligence: A meta-analysis

Is Progressive Ideology on the Test? Education and Intelligence in the Development of Nontraditional Attitudes

Enhanced educational attainment and intelligence are consistent correlates of socially liberal, nontraditional attitudes. However, it is unclear how such associations unfold developmentally. Here, we propose an interaction effect between college exposure and intelligence on the development of nontraditional attitudes. Our rationale builds from the fact that a desired learning outcome of college education is to challenge traditional dogma and encourage diverse perspectives. Those with higher intellectual ability should be particularly adept at understanding the intended lesson and to show attendant increases in nontraditional attitudes. Data on social attitudes were obtained in a large community sample of youth at age 17 and remeasured at two points in early adulthood (N = 2,769). Intelligence was linked with growth in nontraditional attitudes among those with higher educational attainment; no such association was observed among individuals who never attended college. Environments that encourage critical inquiry may thus steer brighter individuals toward the adoption of progressive worldviews.

Genetic Predisposition of Different Social Status Indicators in Men and Women

Although there is evidence that social status has a genetic basis, it is less known whether the genetic predisposition differs between men and women as well as among different status indicators and whether there are any intercorrelations among predispositions of status indicators. We therefore investigated the genetic predisposition for different indicators of social status separately for men and women, using polygenic scores obtained from the Wisconsin Longitudinal Study. We used multivariate polygenic regression of 7 different social status indicators on a total of 24 different polygenic scores. We find that in both men and women, wages and education show more associations with polygenic scores than the other status indicators. Also, the genetic predispositions for education and wages are correlated in both men and women, whereas in men more than in women, the genetic predispositions seem to cluster into wages and education on the one hand, and status indicators of position in the hierarchy, on the other hand, with being in a management position somewhere in between. These findings are consistent with an assumption of two different forms of selection pressure associated with either cognitive skill or dominance, which holds true particularly in men. We conclude that the genetic predisposition to higher social status may have changed even though the importance of the cultural trait of social status may have been very constant. Social status may thus be an example of a social trait of constant importance, but with a changing genetic predisposition.

The computational and neural substrates of individual differences in impulsivity under loss framework

Numerous neuroimaging studies have identified significant individual variability in intertemporal choice, often attributed to three neural mechanisms: (1) increased reward circuit activity, (2) decreased cognitive control, and (3) prospection ability. These mechanisms that explain impulsivity, however, have been primarily studied in the gain domain. This study extends this investigation to the loss domain. We employed a hierarchical Bayesian drift-diffusion model (DDM) and the inter-subject representational similarity approach (IS-RSA) to investigate the potential computational neural substrates underlying impulsivity in loss domain across two experiments (n = 155). These experiments utilized a revised intertemporal task that independently manipulated the amounts of immediate and delayed-loss options. Behavioral results demonstrated positive correlations between the drift rate, measured by the DDM, and the impulsivity index K in Exp. 1 (n = 97) and were replicated in Exp. 2 (n = 58). Imaging analyses further revealed that the drift rate significantly mediated the relations between brain properties (e.g., prefrontal cortex activations and gray matter volume in the orbitofrontal cortex and precuneus) and K in Exp. 1. IS-RSA analyses indicated that variability in the drift rate also mediated the associations between inter-subject variations in activation patterns and individual differences in K. These findings suggest that individuals with similar impulsivity levels are likely to exhibit similar value processing patterns, providing a potential explanation for individual differences in impulsivity within a loss framework.

Do Religiosity and Spirituality Differ in Their Relationship with Crystallized Intelligence? Evidence from the General Social Survey

Negative associations of religiosity and intelligence are well established in psychological research. However, past studies have shown a substantial heterogeneity in reported effect strengths. Causes that may be able to explain the identified inconsistencies pertain to differing religiosity measurement modalities, participant ages, or possibly cohort effects due to changing societal values in terms of being religious. Moreover, little is known about intelligence associations with the religiosity-related yet distinct construct of spirituality. Here, we provide evidence for religiosity and crystallized intelligence, as well as spirituality and crystallized intelligence associations, in 14 cohorts from 1988 to 2022 (N = 35,093) in the General Social Survey data by means of primary data analyses and meta-analytical approaches. As expected, religiosity was non-trivially negatively associated (r = -0.13, p < .001), but spirituality showed no meaningful association with crystallized intelligence (r = 0.03, p < .001). Our results broadly generalized across age groups, cohorts, and analytical approaches, thus suggesting that religiosity and intelligence may possibly be functionally equivalent to a certain extent whilst spirituality represents a distinct construct that is not functionally equivalent.

Healthy dietary choices involve prefrontal mechanisms associated with long-term reward maximization but not working memory

Taste and health are critical factors to be considered when choosing foods. Prioritizing healthiness over tastiness requires self-control. It has also been suggested that self-control is guided by cognitive control. We then hypothesized that neural mechanisms underlying healthy food choice are associated with both self-control and cognitive control. Human participants performed a food choice task and a working memory task during functional MRI scanning. Their degree of self-control was assessed behaviorally by the value discount of delayed monetary rewards in intertemporal choice. Prioritizing healthiness in food choice was associated with greater activity in the superior, dorsolateral, and medial prefrontal cortices. Importantly, the prefrontal activity was greater in individuals with smaller delay discounting (i.e. high self-control) who preferred a delayed larger reward to an immediate smaller reward in intertemporal choice. On the other hand, working memory activity did not show a correlation with delay discounting or food choice activity, which was further supported by supplementary results that analyzed data from the Human Connectome Project. Our results suggest that the prefrontal cortex plays a critical role in healthy food choice, which requires self-control, but not working memory, for maximization of reward attainments in a remote future.

No effects of acute stress on monetary delay discounting: A systematic literature review and meta-analysis

Many everyday decisions, including those concerning our health, finances and the environment, involve choosing between a smaller but imminent reward (e.g., €20 now) and a later but larger reward (e.g., €40 in a month). The extent to which an individual prefers smaller imminent rewards over larger delayed rewards can be measured using delay discounting tasks. Acute stress induces a cascade of biological and psychological responses with potential consequences for how individuals think about the future, process rewards, and make decisions, all of which can impact delay discounting. Several studies have shown that individuals focus more on imminent rewards under stress. These findings have been used to explain why individuals make detrimental choices under acute stress. Yet, the evidence linking acute stress to delay discounting is equivocal. To address this uncertainty, we conducted a meta-analysis of 11 studies (14 effects) to systematically quantify the effects of acute stress on monetary delay discounting. Overall, we find no effect of acute stress on delay discounting, compared to control conditions (SMD = -0.18, 95% CI [-0.57, 0.20], p = 0.32). We also find that neither the gender/sex of the participants, the type of stressor (e.g., physical vs. psychosocial) nor whether monetary decisions were hypothetical or incentivized (i.e. monetary decisions were actually paid out) moderated the impact of acute stress on monetary delay discounting. We argue that establishing the effects of acute stress on the separate processes involved in delay discounting, such as reward valuation and prospection, will help to resolve the inconsistencies in the field.

Predicting political beliefs with polygenic scores for cognitive performance and educational attainment

Intelligence is correlated with a range of left-wing and liberal political beliefs. This may suggest intelligence directly alters our political views. Alternatively, the association may be confounded or mediated by socioeconomic and environmental factors. We studied the effect of intelligence within a sample of over 300 biological and adoptive families, using both measured IQ and polygenic scores for cognitive performance and educational attainment. We found both IQ and polygenic scores significantly predicted all six of our political scales. Polygenic scores predicted social liberalism and lower authoritarianism, within-families. Intelligence was able to significantly predict social liberalism and lower authoritarianism, within families, even after controlling for socioeconomic variables. Our findings may provide the strongest causal inference to date of intelligence directly affecting political beliefs.

Spontaneous neural activity in the three principal networks underlying delay discounting: a resting-state fMRI study

Delay discounting, the decline in the subjective value of future rewards over time, has traditionally been understood through a tripartite neural network model, comprising the valuation, cognitive control, and prospection networks. To investigate the applicability of this model in a resting-state context, we employed a monetary choice questionnaire to quantify delay discounting and utilized resting-state functional magnetic resonance imaging (rs-fMRI) to explore the role of spontaneous brain activity, specifically regional homogeneity (ReHo), in influencing individual differences in delay discounting across a large cohort (N = 257). Preliminary analyses revealed a significant negative correlation between delay discounting tendencies and the ReHo in both the left insula and the right hippocampus, respectively. Subsequent resting-state functional connectivity (RSFC) analyses, using these regions as seed ROIs, disclosed that all implicated brain regions conform to the three principal networks traditionally associated with delay discounting. Our findings offer novel insights into the role of spontaneous neural activity in shaping individual variations in delay discounting at both regional and network levels, providing the first empirical evidence supporting the applicability of the tripartite network model in a resting-state context.

Developmental deviation in delay discounting as a transdiagnostic indicator of risk for child psychopathology

BACKGROUND

The tendency to prefer smaller, immediate rewards over larger, delayed rewards is known as delay discounting (DD). Developmental deviations in DD may be key in characterizing psychiatric and neurodevelopmental disorders. Recent work empirically supported DD as a transdiagnostic process in various psychiatric disorders. Yet, there is a lack of research relating developmental changes in DD from mid-childhood to adolescence to psychiatric and neurodevelopmental disorders. Additionally, examining the interplay between socioeconomic status/total household income (THI) and psychiatric symptoms is vital for a more comprehensive understanding of pediatric pathology and its complex relationship with DD.

METHODS

The current study addresses this gap in a robust psychiatric sample of 1843 children and adolescents aged 5-18 (M = 10.6, SD = 3.17; 1,219 males, 624 females). General additive models (GAMs) characterized the shape of age-related changes in monetary and food reward discounting for nine psychiatric disorders compared with neurotypical youth (NT; n = 123). Over 40% of our sample possessed a minimum of at least three psychiatric or neurodevelopmental disorders. We used bootstrap-enhanced Louvain community detection to map DD-related comorbidity patterns. We derived five subtypes based on diagnostic categories present in our sample. DD patterns were then compared across each of the subtypes. Further, we evaluated the effect of cognitive ability, emotional and behavioral problems, and THI in relation to DD across development.

RESULTS

Higher discounting was found in six of the nine disorders we examined relative to NT. DD was consistently elevated across development for most disorders, except for depressive disorders, with age-specific DD differences compared with NTs. Community detection analyses revealed that one comorbidity subtype consisting primarily of Attention-Deficit/Hyperactivity Disorder (ADHD) Combined Presentation and anxiety disorders displayed the highest overall emotional/behavioral problems and greater DD for the food reward. An additional subtype composed mainly of ADHD, predominantly Inattentive Presentation, learning, and developmental disorders, showed the greatest DD for food and monetary rewards compared with the other subtypes. This subtype had deficits in reasoning ability, evidenced by low cognitive and academic achievement performance. For this ADHD-I and developmental disorders subtype, THI was related to DD across the age span such that participants with high THI showed no differences in DD compared with NTs. In contrast, participants with low THI showed significantly worse DD trajectories than all others. Our results also support prior work showing that DD follows nonlinear developmental patterns.

CONCLUSIONS

We demonstrate preliminary evidence for DD as a transdiagnostic marker of psychiatric and neurodevelopmental disorders in children and adolescents. Comorbidity subtypes illuminate DD heterogeneity, facilitating the identification of high-risk individuals. Importantly, our findings revealed a marked link between DD and intellectual reasoning, with children from lower-income households exhibiting lower reasoning skills and heightened DD. These observations underscore the potential consequences of compromised self-regulation in economically disadvantaged individuals with these disorders, emphasizing the need for tailored interventions and further research to support improved outcomes.

Delay discounting and family history of psychopathology in children ages 9-11

Delay discounting is a tendency to devalue delayed rewards compared to immediate rewards. Evidence suggests that steeper delay discounting is associated with psychiatric disorders across diagnostic categories, but it is unclear whether steeper delay discounting is a risk factor for these disorders. We examined whether children at higher risk for psychiatric disorders, based on family history, would demonstrate steeper delay discounting behavior using data from the Adolescent Brain Cognitive Development (ABCD) study, a nationally representative sample of 11,878 children. We looked at associations between delay discounting behavior and family history of alcohol problems, drug problems, depression, mania, schizophrenia, and suicidal behavior. Correlations between family history of psychopathology and delay discounting behavior were small, ranging from ρ = - 0.02 to 0.04. In mixed effects models controlled for sociodemographic factors, family history of psychopathology was not associated with steeper delay discounting behavior. Sociodemographic factors played a larger role in predicting delay discounting behavior than family history of psychopathology. These results do not support the hypothesis that children with greater risk for psychopathology display steeper delay discounting behavior.

Poke And Delayed Drink Intertemporal Choice Task (POKE-ADDICT): An open-source behavioral apparatus for intertemporal choice testing in rodents

Advancements in neuroscience research present opportunities and challenges, requiring substantial resources and funding. To address this, we describe here "Poke And Delayed Drink Intertemporal Choice Task (POKE-ADDICT)", an open-source, versatile, and cost-effective apparatus for intertemporal choice testing in rodents. This allows quantification of delay discounting (DD), a cross-species phenomenon observed in decision making which provides valuable insights into higher-order cognitive functioning. In DD, the subjective value of a delayed reward is reduced as a function of the delay for its receipt. Using our apparatus, we implemented an effective intertemporal choice paradigm for the quantification of DD based on an adjusting delayed amount (ADA) algorithm using mango juice as a reward. Our paradigm requires limited training, a few 3D-printed parts and inexpensive electrical components, including a Raspberry Pi control unit. Furthermore, it is compatible with several in vivo procedures and the use of nose pokes instead of levers allows for faster task learning. Besides the main application described here, the apparatus can be further extended to implement other behavioral tests and protocols, including standard operant conditioning. In conclusion, we describe a versatile and cost-effective design based on Raspberry Pi that can support research in animal behavior, decision making and, more specifically, delay discounting.

Working memory and attention in choice

We study the role of attention and working memory in choices where options are presented sequentially rather than simultaneously. We build a model where a costly attention effort is chosen, which can vary over time. Evidence is accumulated proportionally to this effort and the utility of the reward. Crucially, the evidence accumulated decays over time. Optimal attention allocation maximizes expected utility from final choice; the optimal solution takes the decay into account, so attention is preferentially devoted to later times; but convexity of the flow attention cost prevents it from being concentrated near the end. We test this model with a choice experiment where participants observe sequentially two options. In our data the option presented first is, everything else being equal, significantly less likely to be chosen. This recency effect has a natural explanation with appropriate parameter values in our model of leaky evidence accumulation, where the decline is stronger for the option observed first. Analysis of choice, response time and brain imaging data provide support for the model. Working memory plays an essential role. The recency bias is stronger for participants with weaker performance in working memory tasks. Also activity in parietal areas, coding the stored value in working, declines over time as predicted.

Excluded and myopic: Social exclusion increases temporal discounting

Social exclusion is a painful yet ubiquitous experience that modulates affect, behavior, and cognition. Decision-making is an essential cognitive ability that some forms of it are altered following social exclusion. However, how intertemporal decision-making is influenced by social exclusion is scarcely studied. Here, using Future Life Alone paradigm we demonstrated that experiencing social exclusion increases temporal discounting. We further tested whether the increased temporal discounting is mediated by either time perception or risk-taking. Our results revealed that although time perception is influenced by social exclusion, neither time perception nor risk-taking mediated the changes in temporal discounting. Our results are providing further evidence corroborating that social exclusion evokes cognitive deconstruction and therefore alters temporal discounting.

Pre-pandemic family resources and child self-regulation in children's internalizing problems during COVID-19: a multi-level social-ecological framework for emotional resilience

Introduction

Children's psychological adjustment to adverse events can be determined by multiple risk and resilience factors. This study explored multi-level protective factors against children's internalizing problems and investigated the mechanism regarding how diverse environmental and child-level resources influence children's mental health in the context of COVID-19.

Methods

Our participants included a nationally representative sample of 2,619 young children (48.3% girls) and their primary caregivers (95.1% mothers) in Singapore. They were a subset of the participants in the Singapore Longitudinal Early Development Study (SG LEADS). Data were collected over two waves-before the outbreak of the COVID-19 pandemic (Wave 1) when these children aged 3 to 6, and during the second year of the pandemic (Wave 2). Primary caregivers completed measures of verbal cognitive ability, self-control, economic stress, and positive and negative parental control in Wave 1. Children's self-regulation was assessed by the Delay of Gratification task in Wave 1, and their internalizing problems were rated by their primary caregivers in both waves. Other pre-pandemic family and community characteristics were collected as covariates. Structural equation modeling was performed.

Results

Pre-pandemic parental resources (i.e., verbal cognitive ability, self-control, and low economic stress) predicted children's fewer internalizing problems during the pandemic and less aggravation of internalizing problems from before to during the pandemic, through more positive parental control (i.e., limit setting) and less negative parental control (i.e., harsh discipline). Moreover, children's self-regulation during early childhood was predicted by their primary caregivers' verbal cognitive ability and self-control, as well as positive parental control. Early childhood self-regulation further alleviated the aggravation of internalizing problems over time. Among the covariates, parental education, family income, parental psychological well-being, living with both parents, having a live-in domestic helper, and neighborhood quality also longitudinally predicted fewer child internalizing problems.

Discussion

Our findings underscore the importance of nurturing children's emotional resilience under adverse and uncertain circumstances by boosting protective factors in their social-ecological system, including community-, family-, parent-, and child-level resources.

Understanding the functional form of the relationship between childhood cognitive ability and adult financial well-being

The increasing complexity of the modern financial landscape presents significant challenges for individuals' financial well-being. In this study, we aim to investigate the relationship between cognitive ability and financial well-being by utilizing data from the British Cohort Study, which follows a sample of 13,000 individuals from birth in 1970 to the present day. Our objective is to examine the functional form of this relationship while controlling for factors such as childhood socio-economic status and adult income. Previous research has established a correlation between cognitive ability and financial well-being, but has implicitly assumed a linear relationship. Our analyses indicate that the majority of the relationships between cognitive ability and financial variables are monotonic. However, we also observe non-monotonic relationships, particularly for credit usage, suggesting a curvilinear relationship where both lower and higher levels of cognitive ability are associated with lower levels of debt. These findings have important implications for understanding the role of cognitive ability in financial well-being and for financial education and policy, as the complexity of the modern financial landscape poses significant challenges for individuals' financial well-being. As financial complexity is increasing and cognitive ability is a key predictor of knowledge acquisition, misspecifying the true relationship between cognitive ability and financial outcomes leads to an undervaluation of the role of cognitive ability for financial well-being.

Model-based experimental manipulation of probabilistic behavior in interpretable behavioral latent variable models

Introduction

Interpretable latent variable models that probabilistically link behavioral observations to an underlying latent process have increasingly been used to draw inferences on cognition from observed behavior. The latent process usually connects experimental variables to cognitive computation. While such models provide important insights into the latent processes generating behavior, one important aspect has often been overlooked. They may also be used to generate precise and falsifiable behavioral predictions as a function of the modeled experimental variables. In doing so, they pinpoint how experimental conditions must be designed to elicit desired behavior and generate adaptive experiments.

Methods

These ideas are exemplified on the process of delay discounting (DD). After inferring DD models from behavior on a typical DD task, the models are leveraged to generate a second adaptive DD task. Experimental trials in this task are designed to elicit 9 graded behavioral discounting probabilities across participants. Models are then validated and contrasted to competing models in the field by assessing the ouf-of-sample prediction error.

Results

The proposed framework induces discounting probabilities on nine levels. In contrast to several alternative models, the applied model exhibits high validity as indicated by a comparably low prediction error. We also report evidence for inter-individual differences with respect to the most suitable models underlying behavior. Finally, we outline how to adapt the proposed method to the investigation of other cognitive processes including reinforcement learning.

Discussion

Inducing graded behavioral frequencies with the proposed framework may help to highly resolve the underlying cognitive construct and associated neuronal substrates.

Waiting for a better possibility: delay of gratification in corvids and its relationship to other cognitive capacities

Self-control, the ability to resist temptation and wait for better but delayed possibilities, is an important cognitive skill that underpins decision-making and planning. The capacity to exert self-control has been linked to intelligence in humans, chimpanzees and most recently cuttlefish. Here, we presented 10 Eurasian jays, Garrulus glandarius, with a delayed maintenance task, which measured the ability to choose a preferred outcome as well as the ability to sustain the delay prior to that outcome. Jays were able to wait for better possibilities, but maximum wait times varied across the subjects. We also presented them with five cognitive tasks that assessed spatial memory, spatial relationships and learning capacity. These tasks are commonly used as measures of general intelligence within an ecological context. Individual performance was correlated across the cognitive tasks, which suggests that there was a general intelligence factor underlying their performance. Performance in these tasks was correlated significantly with the jays' capacity to wait for better possibilities. This study demonstrates that self-control and intelligence are correlated in jays. The fact that this correlation exists in diverse species suggests that self-control is a fundamental feature of cognition. Our results are discussed in the context of convergent evolution.

This article is part of the theme issue ‘Thinking about possibilities: mechanisms, ontogeny, functions and phylogeny’.

A neural signature of the vividness of prospective thought is modulated by temporal proximity during intertemporal decision making

Why do people discount future rewards? Multiple theories in psychology argue that one reason is that future events are imagined less vividly than immediate events, thereby diminishing their perceived value. Here we provide neuroscientific evidence for this proposal. First, we construct a neural signature of the vividness of prospective thought, using an fMRI dataset where the vividness of imagined future events is orthogonal to their valence by design. Then, we apply this neural signature in two additional fMRI datasets, each using a different delay-discounting task, to show that neural measures of vividness decline as rewards are delayed farther into the future.

Episodic future thinking predicts differences in delay discounting: The mediating role of hippocampal structure

A growing body of evidence suggests that engagement in episodic future thinking (EFT) could reduce delay discounting rates. However, little is known about whether individual differences in the ability of EFT are associated with differences in delay discounting in young adults. In the present study, this association was tested in healthy college students (n = 106, 19.98 ± 1.56 years), and the neural basis underlying this association was also examined using voxel-based morphometry (VBM) method. Behavioral analysis indicated that individual differences in EFT ability can significantly negatively predict discounting rates. VBM analysis first revealed that the EFT score positively correlated with gray matter volume (GMV) of a cluster in hippocampus, while negatively correlated with GMV of a cluster in rostral anterior cingulate cortex. We also found the GMV of a cluster in the mPFC was positively correlated with delay discounting. ROI analysis further revealed that individual differences in delay discounting could be reliably predicted by the GMV in the hippocampus and mPFC. The final mediation analysis showed that the GMV of the hippocampus plays a significant mediating role in the association between EFT and delay discounting, and the indirect effect of the hippocampal GMV accounts for 33.2% of the total effect. Our results suggest that individuals’ EFT ability may be an important determinant of differences in delay discounting, and highlight the hippocampal structure as a neural biomarker for explaining the association between EFT ability and delay discounting.

Fronto-striatal connectivity patterns account for the impact of methylphenidate on choice impulsivity among healthy adults

Choice impulsivity depicts a preference towards smaller-sooner rewards over larger-delayed rewards, and is often assessed using a delay discounting (DD) task. Previous research uncovered the prominent role of dopaminergic signaling within fronto-striatal circuits in mediating choice impulsivity. Administration of methylphenidate (MPH), an indirect dopaminergic agonist, was shown to reduce choice impulsivity in animals and pathological populations, although significant inter-individual variability in these effects was reported. Whether MPH impacts choice impulsivity among healthy individuals, and whether variability in the impact of MPH is related to fronto-striatal activation and connectivity patterns, has yet to be assessed. Here, fifty-seven healthy young adults completed the DD task twice during fMRI scans, after acute administration of either MPH (20 mg) or placebo, in a randomized double-blind placebo-controlled design. Acute MPH administration was found to reduce choice impulsivity at the group level, yet substantial variability in this behavioral response was observed. MPH was also found to increase activation in the bilateral putamen and the right caudate, and to enhance functional connectivity between the left putamen and medial prefrontal cortex (mPFC), particularly during non-impulsive choices. Notably, the more putamen-mPFC functional connectivity increased during non-impulsive choices following MPH administration, the less an individual was likely to make impulsive choices. These findings reveal, for the first time in healthy adults, that acute MPH administration is associated with reduced choice impulsivity and increased striatal activation and fronto-striatal connectivity; and furthermore, that the magnitude of MPH-induced change in fronto-striatal connectivity may account for individual differences in the impact of MPH on impulsive behavior.

Neuroanatomical foundations of delayed reward discounting decision making II: Evaluation of sulcal morphology and fractal dimensionality

Delayed reward discounting (DRD) is a form of decision-making reflecting valuation of smaller immediate rewards versus larger delayed rewards, and high DRD has been linked to several health behaviors, including substance use disorders, attention-deficit/hyperactivity disorder, and obesity. Elucidating the underlying neuroanatomical factors may offer important insights into the etiology of these conditions. We used structural MRI scans of 1038 Human Connectome Project participants (M_age = 28.86, 54.7% female) to explore two novel measures of neuroanatomy related to DRD: 1) sulcal morphology (SM; depth and width) and 2) fractal dimensionality (FD), or cortical morphometric complexity, of parcellated cortical and subcortical regions. To ascertain unique contributions to DRD preferences, indicators that displayed significant partial correlations with DRD after family-wise error correction were entered into iterative mixed-effect models guided by the association magnitude. When considering only SM indicators, the depth of the right inferior and width of the left central sulci were uniquely associated with DRD preferences. When considering only FD indicators, the FD of the left middle temporal gyrus, right lateral orbitofrontal cortex, and left lateral occipital and entorhinal cortices uniquely contributed DRD. When considering SM and FD indicators simultaneously, the right inferior frontal sulcus depth and left central sulcus width; and the FD of the left middle temporal gyrus, lateral occipital cortex and entorhinal cortex were uniquely associated with DRD. These results implicate SM and FD as features of the brain that underlie variation in the DRD decision-making phenotype and as promising candidates for understanding DRD as a biobehavioral disease process.

The contribution of executive functions to sex differences in animal cognition

Cognitive sex differences have been reported in several vertebrate species, mostly in spatial abilities. Here, I review evidence of sex differences in a family of general cognitive functions that control behaviour and cognition, i.e., executive functions such as cognitive flexibility and inhibitory control. Most of this evidence derives from studies in teleost fish. However, analysis of literature from other fields (e.g., biomedicine, genetic, ecology) concerning mammals and birds reveals that more than 40% of species investigated exhibit sex differences in executive functions. Among species, the direction and magnitude of these sex differences vary greatly, even within the same family, suggesting sex-specific selection due to species' reproductive systems and reproductive roles of males and females. Evidence also suggests that sex differences in executive functions might provide males and females highly differentiated cognitive phenotypes. To understand the evolution of cognitive sex differences in vertebrates, future research should consider executive functions.

Do Patterns of Levels of Socio-emotional Competence During Early Childhood Predict Executive Function at 4.5 Years?

Socio-emotional competence and executive function both work together to meet the demands of the everyday environment. While many studies have focused on how various domains of socio-emotional competence are predicted by, or associated with executive function, the predictive influence of socio-emotional competence on executive function has largely been ignored despite strong theoretical links. In addition, contradictory information exists with regard to the divergent validity of two subtypes of executive function: cool and hot. Using data from 4839 children participating in three data collection waves (9 months, 2 years and 4.5 year) in the Growing Up in New Zealand longitudinal study, we examined how different patterns of socio-emotional competence development during the early preschool years (persistent lows, recent low, improved and no lows) related to cool and hot executive function measured at aged 4.5 using a hand clap task and a gift wrap task, respectively. Findings showed that children with persistent lows (with no improvement) in the levels of early socio-emotional competence had increased odds of having below average cool and hot executive function at 4.5 years. However, no difference was found in the influence of socio-emotional competence on cool and hot executive function. Possible explanations for these associations between socio-emotional competence and executive function are discussed.

Empathy, Self-control, Callous-Unemotionality, and Delinquency: Unique and Shared Developmental Antecedents

The current investigation tested childhood developmental antecedents of adolescent empathy, self-control, callous-unemotionality, and delinquency, namely difficult temperament, positive socialization experiences, and intelligence; it also tested potential mediation effects of temperament via socialization. Data were collected as part of the National Institute of Child Health and Human Development Early Child Care and Youth Development Study, which followed N = 1364 children from birth through 15 years (51% female, 80% European American). Early positive socialization (maternal sensitivity, secure attachment, and quality home environment) and temperament variables were assessed from 1 to 36 months, intelligence at age 9, and self-control, empathy, callous-unemotionality, and delinquency at age 15. Based on structural equation modeling hypothesis tests, early positive socialization positively predicted self-control and empathy, and negatively predicted callous-unemotionality and delinquency. Intelligence uniquely and positively predicted empathy. Difficult infant temperament indirectly predicted each of the four traits through early positive socialization. Important research and practical implications are discussed.

The Resting-State Neural Network of Delay Discounting

Delay discounting is a common phenomenon in daily life, which refers to the subjective value of a future reward decreasing as a function of time. Previous studies have identified several cortical regions involved in delay discounting, but the neural network constructed by the cortical regions of delay discounting is less clear. In this study, we employed resting-state functional magnetic resonance imaging (RS-fMRI) to measure the spontaneous neural activity in a large sample of healthy young adults and used the Monetary Choice Questionnaire to directly measure participants’ level of delay discounting. To identify the neural network of delay discounting at rest, we used an individual difference approach to explore brain regions whose spontaneous activities were related to delay discounting across the whole brain. Then, these brain regions served as seeds to identify the neural network of delay discounting. We found that the fractional amplitude of low-frequency fluctuations (fALFF) of the left insula were positively correlated to delay discounting. More importantly, its connectivity to the anterior cingulate cortex was read out for participants’ behavioral performance in the task of delay discounting. In short, our study provides empirical evidence that insula-anterior cingulate cortex connectivity may serve as a part of the neural network for delay discounting.

Time Preference for Immediate Gratification: Associations With Low Medication Adherence and Uncontrolled Blood Pressure

BACKGROUND

In search of innovative approaches to the challenge of uncontrolled hypertension, we assessed the association between preference for immediate gratification (i.e., high discounting rate), low medication adherence, and uncontrolled blood pressure (BP) in adults with hypertension.

METHODS

Using a probability discounting model and the Collier-Williams hypothetical discount rate framework, participants in this cross-sectional study reported their preference for a smaller amount of money available immediately (high discount rate; immediate gratification preference) vs. a larger amount available 1 year later (low discount rate; delayed gratification preference). Multivariable Poisson regression was used to test the association of high discounting rates with low antihypertensive medication adherence using the validated 4-item Krousel-Wood Medication Adherence Scale (K-Wood-MAS-4 score ≥1). Mediation of the association between high discounting rate and uncontrolled BP (systolic/diastolic BP ≥ 130/80 mm Hg) by low adherence was tested using the counterfactual approach.

RESULTS

Among 235 participants (mean age 63.7 ± 6.7 years; 51.1% women; 41.9% Black), 50.6% had a high 1-year discount rate, 51.9% had low K-Wood-MAS-4 adherence, and 59.6% had uncontrolled BP. High discounting rates were associated with low adherence (adjusted prevalence ratio 1.58, 95% confidence interval (CI) 1.18, 2.12). Forty-three percent (95% CI 40.9%, 45.8%) of the total effect of high discount rate on uncontrolled BP was mediated by low adherence.

CONCLUSIONS

Adults with preference for immediate gratification had worse adherence; low adherence partially mediated the association of high discount rate with uncontrolled BP. These results support preference for immediate gratification as an innovative factor underlying low medication adherence and uncontrolled BP.

Differential Effects of Fundamental and Longitudinal Life History Trade-Offs on Delay Discounting: An Evolutionary Framework

We synthesized life history theory and the antagonistic pleiotropy hypothesis to form an integrative framework for understanding delay discounting (DD). We distinguished between fundamental and longitudinal life history trade-offs to explain individual and age differences of DD. Fundamental life history trade-offs are characterized by life history strategies (LHS), describing how individuals adjust reproductive timing according to childhood environments, while longitudinal life history trade-offs characterize how individuals make trade-offs between early- vs. late-life reproduction as a function of age. Results of a life-span sample (242 Chinese participants) supported several theoretical predictions: (a) slower LHS predicted lower DD; (b) the relationship between chronological age and DD was U-shaped; (c) the effects of age and LHS were differential. Mechanisms underlying fundamental and longitudinal trade-offs were explored. Regarding fundamental trade-offs, LHS mediated the effects of childhood environment on DD. Regarding longitudinal trade-offs, the U-shaped relationship was more evident between physical age and DD: older adults who were in poorer physical health felt older and exhibited a higher DD. Neither the time perspective nor anticipatory time perception mediated the effect of life history trade-offs. We concluded that DD was a product of two distinct life history trade-offs, reflecting both the trait-like quality and age-related development.

Hyperbolic discounting rates and risk for problematic alcohol use in youth enrolled in the Adolescent Brain and Cognitive Development study

Adolescence is the peak period for the emergence of substance use, which can lead to long-term psychosocial, occupational and interpersonal complications. Ongoing large-scale, longitudinal, consortium initiatives, such as the Adolescent Brain and Cognitive Development (ABCD) study, offer unprecedented opportunities to elucidate key risk factors for problematic substance use in a well-powered sample and to examine how changes in risk factors relate to symptoms across time. Delay discounting has been proposed as a putative risk marker for early substance-use initiation and other forms of psychopathology. However, the extent to which other factors (e.g., socio-economic status and cognitive ability) influence discounting behaviour in young adolescents is not well established. The present study leverages data from the ABCD study (n = 11 045) to assess associations between core demographic and familial variables and delay discounting in youth-operationalized using hyperbolic discounting rates (k)-before the onset of significant psychopathology. Model estimates revealed significant effects of individual difference factors (e.g., sex and socio-economic status) and alcohol risk status (based on family history) on delay discounting. No significant differences were observed in the primary sample when comparing the presence of parent drug problems or prenatal drug exposures. These effects will require replication in later waves of ABCD. Nonetheless, these results provide support for delay discounting as a potential risk marker for problematic alcohol use and demonstrate a relationship between key demographic variables and adolescent discounting behaviour. Further, these results provide an empirical baseline from which developmental trajectories of delay discounting and substance use may be tracked throughout future waves of ABCD.

Unifying Evidence on Delay Discounting: Open Task, Analysis Tutorial, and Normative Data from an Italian Sample

Despite the widespread use of the delay discounting task in clinical and non-clinical contexts, several task versions are available in the literature, making it hard to compare results across studies. Moreover, normative data are not available to evaluate individual performances. The present study aims to propose a unified version of the delay discounting task based on monetary rewards and it provides normative values built on an Italian sample of 357 healthy participants. The most used parameters in the literature to assess the delay discount rate were compared to find the most valid index to discriminate between normative data and a clinical population who typically present impulsivity issues, i.e., patients with a lesion to the medial orbitofrontal cortex (mOFC). In line with our hypothesis, mOFC patients showed higher delay discounting scores than the normative sample and the normative group. Based on this evidence, we propose that the task and indexes here provided can be used to identify extremely high (above the 90th percentile for hyperbolic k or below the 10th percentile for AUC) or low (below the 10th percentile for hyperbolic k or above the 90th percentile for AUC) delay discounting performances. The complete dataset, the R code used to perform all analyses, a free and modifiable version of the delay discounting task, as well as the R code that can be used to extract all indexes from such tasks and compare subjective performances with the normative data here presented are available as online materials.

Psychological correlates of free colorectal cancer screening uptake in a Scottish sample: a cross-sectional observational study

OBJECTIVES

Colorectal cancer (CRC) screening uptake in Scotland is 56%. This study examined whether psychological factors were associated with CRC screening uptake.

DESIGN

Cross-sectional observational study.

SETTING

This study used data from the Healthy AGeing In Scotland (HAGIS) pilot study, a study designed to be representative of Scottish adults aged 50 years and older.

PARTICIPANTS

908 (505 female) Scottish adults aged 50-80 years (mean age=65.85, SD=8.23), who took part in the HAGIS study (2016-2017).

PRIMARY AND SECONDARY OUTCOME MEASURES

Self-reported participation in CRC screening was the outcome measure. Logistic regression was used to test whether scores on measures of health literacy, cognitive ability, risk aversion, time preference (eg, present oriented or future oriented) and personality were associated with CRC screening when these psychological factors were entered individually and simultaneously in the same model.

RESULTS

Controlling for age, age-squared, sex, living arrangement, and sex*living arrangement, a one-point increase in risk aversion (OR=0.66, 95% CI 0.51 to 0.85) and present orientation (OR=0.86, 95% CI 0.80 to 0.94) was associated with reduced odds of screening. Higher scores on health literacy (OR per one-point increase=1.20, 95% CI 1.09 to 1.31), cognitive ability (OR per SD increase=1.51, 95% CI 1.25 to 1.81) and the intellect personality trait (OR per one-point increase=1.05, 95% CI 1.01 to 1.09) were associated with increased odds of screening. Higher risk aversion was the only psychological variable that was associated with CRC screening participation when all psychological variables were entered in the same model and remained associated with CRC screening when additionally adjusting for deprivation and education. A backward elimination model retained two psychological variables as correlates of CRC screening: risk aversion and cognitive ability.

CONCLUSION

Individuals who are more risk averse are less likely to participate in free, home CRC screening.

Cognitive and Affective Empathy Relate Differentially to Emotion Regulation

The constructs of empathy (i.e., understanding and/or sharing another's emotion) and emotion regulation (i.e., the processes by which one manages emotions) have largely been studied in relative isolation of one another. To better understand the interrelationships between their various component processes, this manuscript reports two studies that examined the relationship between empathy and emotion regulation using a combination of self-report and task measures. In study 1 (N = 137), trait cognitive empathy and affective empathy were found to share divergent relationships with self-reported emotion dysregulation. Trait emotion dysregulation was negatively related to cognitive empathy but did not show a significant relationship with affective empathy. In the second study (N = 92), the magnitude of emotion interference effects (i.e., the extent to which inhibitory control was impacted by emotional relative to neutral stimuli) in variants of a Go/NoGo and Stroop task were used as proxy measures of implicit emotion regulation abilities. Trait cognitive and affective empathy were differentially related to both task metrics. Higher affective empathy was associated with increased emotional interference in the Emotional Go/NoGo task; no such relationship was observed for trait cognitive empathy. In the Emotional Stroop task, higher cognitive empathy was associated with reduced emotional interference; no such relationship was observed for affective empathy. Together, these studies demonstrate that greater cognitive empathy was broadly associated with improved emotion regulation abilities, while greater affective empathy was typically associated with increased difficulties with emotion regulation. These findings point to the need for assessing the different components of empathy in psychopathological conditions marked by difficulties in emotion regulation.

Supplementary Information

The online version contains supplementary material available at 10.1007/s42761-021-00062-w.

Age-related effects in delay discounting for food

Developmental influences of growth, such as hormones and metabolic factors, increase food intake and weight across the lifespan. Delay discounting (DD), a choice procedure that characterizes preferences for immediate rewards, such as food, over larger, more delayed ones may be useful in understanding developmental and metabolic changes in decision making processes related to food intake. The present study examined the relation between age and food DD in a cross-sectional design. Other variables, such as pubertal stage, were examined also as these may influence discounting. Participants (N = 114; 28 children and 86 adult) from a community sample completed measures of food and money delay discounting to determine if age-related variation in discounting tendencies is food-specific or more general. Both measures yield an omnibus discounting value and three additional values for small, medium, and large magnitudes. Analyses first revealed magnitude effects-- smaller magnitudes of both food and money were discounted more steeply than larger magnitudes. Hierarchical regressions indicated subjective hunger predicted steeper food discounting. When subjective hunger was controlled, age, but not puberty, significantly predicted food discounting for omnibus, medium, and large magnitudes of food. In children, food discounting decreased from early childhood to late adolescence. In adults, food discounting increased from early to late adulthood. Neither age, puberty, nor obesity status predicted any measure of monetary discounting. Food discounting, then, appears to change across the lifespan, and therefore, may be appropriate to examine psychological processes that accompany developmental and metabolic changes across the lifespan.

The effect of working memory capacity and training on intertemporal decision making in children from low-socioeconomic-status families

Individuals differ in their tendency to discount delayed rewards. Low socioeconomic status (SES) has been found to be associated with strong delayed reward discounting (DRD), which in turn contributes to risky decision making and adverse behaviors. However, research on possible cognitive mediators of the negative association between SES and DRD, and on effects of cognitive training in low-SES adolescents, is largely lacking. In examining Chinese adolescents (aged 11-15 years; N = 207), Study 1 assessed which aspect of working memory (WM)-simple maintenance, simple manipulation, or updating-serves as mediator, which proved to be WM updating. Based on this outcome, in Study 2 Chinese adolescents (aged 12-14 years; N = 73) with low family SES were assigned to a WM updating training condition or a control condition. All participants performed DRD and WM tasks before and after treatment. The trained adolescents showed positive training effects on DRD, and this effect was specifically correlated with beneficial training effects on performance on a WM updating transfer task. These results support the role of WM updating in DRD and might inform training programs to promote more favorable decision making in low-SES adolescents.

Quantifying the contribution of individual variation in timing to delay-discounting

Delay-discounting studies in neuroscience, psychology, and economics have been mostly focused on concepts of self-control, reward evaluation, and discounting. Another important relationship to consider is the link between intertemporal choice and time perception. We presented 50 college students with timing tasks on the range of seconds to minutes and intertemporal-choice tasks on both the time-scale of seconds and of days. We hypothesized that individual differences in time perception would influence decisions about short experienced delays but not long delays. While we found some evidence that individual differences in internal clock speed account for some unexplained variance between choices across time-horizons, overall our findings suggest a nominal contribution of the altered sense of time in intertemporal choice.

Are Impulsive Decisions Always Irrational? An Experimental Investigation of Impulsive Decisions in the Domains of Gains and Losses

Intertemporal choices are very prevalent in daily life, ranging from simple, mundane decisions to highly consequential decisions. In this context, thinking about the future and making sound decisions are crucial to promoting mental and physical health, as well as a financially sustainable lifestyle. In the present study, we set out to investigate some of the possible underlying mechanisms, such as cognitive factors and emotional states, that promote future-oriented decisions. In a cross-sectional experimental study, we used a gain and a loss version of an intertemporal monetary choices task. Our main behavioural result indicated that people are substantially more impulsive over smaller and sooner monetary losses compared to equivalent gains. In addition, for both decisional domains, significant individual difference predictors emerged, indicating that intertemporal choices are sensitive to the affective and cognitive parameters. By focusing on the cognitive and emotional individual factors that influence impulsive decisions, our study could constitute a building block for successful future intervention programs targeted at mental and physical health issues, including gambling behaviour.

Delay discounting in youth at clinical high-risk for psychosis and adults with schizophrenia

BACKGROUND

Schizophrenia (SZ) is typically preceded by a prodromal (i.e. pre-illness) period characterized by attenuated positive symptoms and declining functional outcome. Negative symptoms are prominent among individuals at clinical high-risk (CHR) for psychosis (i.e. those with prodromal syndromes) and highly predictive of conversion to illness. Mechanisms underlying negative symptoms in the CHR population are unclear. Two studies were conducted to evaluate whether abnormalities in a reward processing mechanism thought to be core to negative symptoms in SZ, value representation, also exist in CHR individuals and whether they are associated with negative symptoms transphasically.

METHODS

Study 1 included 33 individuals in the chronic phase of illness who have been diagnosed with schizophrenia or schizoaffective disorder (SZ) and 40 healthy controls (CN). Study 2 included 37 CHR participants and 45 CN. In both studies, participants completed the delay discounting (DD) task as a measure of value representation and the Brief Negative Symptom Scale was rated to measure negative symptoms.

RESULTS

Results indicated that patients with SZ had steeper discounting rates than CN, indicating impairments in value representation. However, CHR participants were unimpaired on the DD task. In both studies, steeper discounting was associated with greater severity of negative symptoms.

CONCLUSIONS

These findings suggest that deficits in value representation are associated with negative symptoms transphasically.

The problems with delay discounting: a critical review of current practices and clinical applications

Delay discounting paradigms have gained widespread popularity across clinical research. Given the prevalence in the field, researchers have set lofty expectations for the importance of delay discounting as a key transdiagnostic process and a 'core' process underlying specific domains of dysfunction (e.g. addiction). We believe delay discounting has been prematurely reified as, in and of itself, a core process underlying psychological dysfunction, despite significant concerns with the construct validity of discounting rates. Specifically, high delay discounting rates are only modestly related to measures of psychological dysfunction and therefore are not 'core' to these more complex behavioral problems. Furthermore, discounting rates do not appear to be specifically related to any disorder(s) or dimension(s) of psychopathology. This raises fundamental concerns about the utility of discounting, if the measure is only loosely associated with most forms of psychopathology. This stands in striking contrast to claims that discounting can serve as a 'marker' for specific disorders, despite never demonstrating adequate sensitivity or specificity for any disorder that we are aware of. Finally, empirical evidence does not support the generalizability of discounting rates to other decisions made either in the lab or in the real-world, and therefore discounting rates cannot and should not serve as a summary measure of an individual's decision-making patterns. We provide recommendations for improving future delay discounting research, but also strongly encourage researchers to consider whether the empirical evidence supports the field's hyper-focus on discounting.

Effects of tDCS on reward responsiveness and valuation in Parkinson's patients with impulse control disorders

Parkinson's disease (PD) patients with impulse control disorders (ICD) frequently report hypersensitivity to rewards. However, a few studies have explored the effectiveness of modulation techniques on symptoms experienced by these patients. In this study, we assessed the effect of anodal tDCS over the DLPFC on reward responsiveness and valuation in PD patients with ICD. 43 participants (15 PD patients with ICD, 13 PD without ICD, and 15 healthy matched controls) were asked to perform a reward-craving test employing both explicit (self-ratings of liking and wanting) and implicit (heart rate and skin conductance response) measures, as well as two temporal discounting tasks with food and money rewards. Each participant performed the experimental tasks during active anodal tDCS of the left dorsolateral prefrontal cortex (DLPFC), anodal tDCS of the primary motor cortex (M1), and sham tDCS. Results showed increased wanting and a steeper temporal discounting of rewards in PD with ICD compared to the other groups. Moreover, we found that PD without ICD exhibit reduced liking for rewards. tDCS results capable to modulate the altered intensity of PD patients' liking, but not wanting and temporal discounting of rewards in PD patients with ICD. These findings confirm that alterations in reward responsiveness and valuation are characteristics of impulse control disorders in patients with PD but suggest that anodal tDCS over the left DLPFC is not capable to influence these processes. At the same time, they provide new insight into affective experience of rewards in PD.

Residual Effects of Cannabis Use on Effort-Based Decision-Making

OBJECTIVE

Acute Δ9-tetrahydrocannabinol (THC) administration in humans (Lawn etal., 2016) and rats (Silveira, Adams, Morena, Hill, & Winstanley, 2016) has been associated with decreased effort allocation that may explain amotivation during acute cannabis intoxication. To date, however, whether residual effects of cannabis use on effort-based decision-making are present and observable in humans have not yet been determined. The goal of this study was to test whether prolonged cannabis use has residual effects on effort-based decision-making in 24-hr abstinent cannabis using adults.

METHOD

We evaluated performance on the Effort Expenditure for Reward Task (EEfRT) in 41 adult cannabis users (mean age = 24.63 years, 21 males) and 45 nonusers (mean age = 23.90 years, 19 males). A mixed 2x3x3 ANOVA with age as a covariate was performed to examine the effect of group, probability of winning, and reward amount on EEfRT performance. EEfRT performance was operationalized as % of trials for which the hard (vs. easy) condition was chosen. Pearson's correlations were conducted to test the relationship between EEfRT performance and measures of cannabis use, anhedonia and motivation.

RESULTS

We found that cannabis users selected hard trials significantly more than nonusers regardless of win probability or reward level. Frequency of cannabis use was positively correlated with amount of % hard trials chosen. There were no significant correlations between % hard trials chosen, self-reported anhedonia, or motivation.

CONCLUSIONS

These results suggest that unlike acute effects, residual effects of cannabis following 24 hrs of abstinence are associated with greater effort allocation during effort-based decision-making.

Association of General Cognitive Functions with Gaming Use in Young Adults: A Comparison among Excessive Gamers, Regular Gamers and Non-Gamers

This study aimed to examine the relationship of general cognitive function with gaming use, and to identify elements of intelligence predicting increased gaming use. In total, 160 young adults participated in this study. Two clinical groups (n = 97) were defined: excessive gaming users diagnosed with internet gaming disorder (IGD) (n = 64) and the high-risk users (n = 33). The control group (n = 63) was also divided into regular gamers (n = 14) and non-gamers (n = 49). Participants completed the Wechsler Adult Intelligence Scale-IV and self-reported questionnaires regarding IGD severity and gaming hours. The IGD group had significantly lower Full Scale Intelligence Quotient (FSIQ), Verbal Comprehension Index (VCI), and Processing Speed Index (PSI) scores, compared with regular gamers and non-gamers. The IGD group also exhibited lower Working Memory Index (WMI) scores, compared with non-gamers. The high-risk group demonstrated significantly lower PSI score, compared with non-gamers. Furthermore FSIQ, VCI, WMI, and PSI scores were significant predictors of gaming hours in the IGD group. For the high-risk group, FSIQ, WMI, and VCI scores were negatively associated with gaming hours. Our study demonstrates the need to address the importance of enhancing working memory and verbal ability, thus, preventing the development of gaming addiction among individuals at high-risk gamers.

Individual Differences in Intertemporal Choice

Intertemporal choice involves deciding between smaller, sooner and larger, later rewards. People tend to prefer smaller rewards that are available earlier to larger rewards available later, a phenomenon referred to as temporal or delay discounting. Despite its ubiquity in human and non-human animals, temporal discounting is subject to considerable individual differences. Here, we provide a critical narrative review of this literature and make suggestions for future work. We conclude that temporal discounting is associated with key socio-economic and health-related variables. Regarding personality, large-scale studies have found steeper temporal discounting to be associated with higher levels of self-reported impulsivity and extraversion; however, effect sizes are small. Temporal discounting correlates negatively with future-oriented cognitive styles and inhibitory control, again with small effect sizes. There are consistent associations between steeper temporal discounting and lower intelligence, with effect sizes exceeding those of personality or cognitive variables, although socio-demographic moderator variables may play a role. Neuroimaging evidence of brain structural and functional correlates is not yet consistent, neither with regard to areas nor directions of effects. Finally, following early candidate gene studies, recent Genome Wide Association Study (GWAS) approaches have revealed the molecular genetic architecture of temporal discounting to be more complex than initially thought. Overall, the study of individual differences in temporal discounting is a maturing field that has produced some replicable findings. Effect sizes are small-to-medium, necessitating future hypothesis-driven work that prioritizes large samples with adequate power calculations. More research is also needed regarding the neural origins of individual differences in temporal discounting as well as the mediating neural mechanisms of associations of temporal discounting with personality and cognitive variables.

Delay discounting, cognitive ability, and personality: What matters?

Steep delay discounting is associated with problems such as addiction, obesity, and risky sexual behavior that are frequently described as reflecting impulsiveness and lack of self-control, but it may simply indicate poor cognitive functioning. The present investigation took advantage of the unique opportunity provided by the Human Connectome Project (N=1,206) to examine the relation between delay discounting and 11 cognitive tasks as well as the Big Five fundamental personality traits. With income level and education statistically controlled, discounting was correlated with only four of the 11 cognitive abilities evaluated, although the rs were all small (<.20). Importantly, the two discounting measures loaded on their own factor. Discounting was not correlated with Neuroticism or Conscientiousness, traits related to psychometric impulsiveness and self-control. These findings suggest that steep delay discounting is not simply an indicator of poor cognitive functioning or psychometric impulsiveness but an important individual difference characteristic in its own right.

More Later: Delay of Gratification and Thought About the Future in Children

We investigated whether individual differences in future time perception and the detail with which future events are imagined are related to children's delay of gratification. We administered a delay choice task (real rewards), a delay discounting task (hypothetical rewards), a novel future time perception measure, an episodic future thinking (EFT) interview and IQ measures to a sample of 7- to 11-year-olds (N = 132) drawn from a urban predominately white population in N. Ireland. We found a strong correlation between delay choice and delay discounting. Future time perception and EFT were related to delay discounting, however only the relation with future time perception survived controlling for age and IQ. Children who showed greater compression of future time periods were the steepest discounters.

A Meta-Analytic Review of Sex Differences on Delay of Gratification and Temporal Discounting Tasks in ADHD and Typically Developing Samples

Objective: To examine whether males and females with ADHD differ in their preferences for delayed rewards, since there is some evidence that suggests a sex difference with typically developing (TD) samples. Method: We used meta-analyses to examine sex differences on delay of gratification and temporal discounting tasks in both TD and ADHD samples. We identified 28 papers with 52 effect sizes for children and adults, and calculated the average effect size for sex comparisons within TD and ADHD samples. Results: The estimated mean difference between TD males and TD females was negligible, but males with ADHD were more likely to choose the larger delayed rewards than females with ADHD. Meta-regressions indicated that task type, age, and reward type did not significantly predict sex differences. Conclusion: These findings suggest that females referred for ADHD may make less adaptive choices by preferring smaller immediate rewards over larger delayed rewards more often than males with ADHD. Implications of our findings are discussed.

Flexible Utility Function Approximation via Cubic Bezier Splines

In intertemporal and risky choice decisions, parametric utility models are widely used for predicting choice and measuring individuals' impulsivity and risk aversion. However, parametric utility models cannot describe data deviating from their assumed functional form. We propose a novel method using cubic Bezier splines (CBS) to flexibly model smooth and monotonic utility functions that can be fit to any dataset. CBS shows higher descriptive and predictive accuracy over extant parametric models and can identify common yet novel patterns of behavior that are inconsistent with extant parametric models. Furthermore, CBS provides measures of impulsivity and risk aversion that do not depend on parametric model assumptions.

Interactions between decision-making and emotion in behavioral-variant frontotemporal dementia and Alzheimer's disease

Negative and positive emotions are known to shape decision-making toward more or less impulsive responses, respectively. Decision-making and emotion processing are underpinned by shared brain regions including the ventromedial prefrontal cortex (vmPFC) and the amygdala. How these processes interact at the behavioral and brain levels is still unclear. We used a lesion model to address this question. Study participants included individuals diagnosed with behavioral-variant frontotemporal dementia (bvFTD, n = 18), who typically present deficits in decision-making/emotion processing and atrophy of the vmPFC, individuals with Alzheimer’s disease (AD, n = 12) who present with atrophy in limbic structures and age-matched healthy controls (CTRL, n = 15). Prior to each choice on the delay discounting task participants were cued with a positive, negative or neutral picture and asked to vividly imagine witnessing the event. As hypothesized, our findings showed that bvFTD patients were more impulsive than AD patients and CTRL and did not show any emotion-related modulation of delay discounting rate. In contrast, AD patients showed increased impulsivity when primed by negative emotion. This increased impulsivity was associated with reduced integrity of bilateral amygdala in AD but not in bvFTD. Altogether, our results indicate that decision-making and emotion interact at the level of the amygdala supporting findings from animal studies.

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.

Rapid, precise, and reliable measurement of delay discounting using a Bayesian learning algorithm

Machine learning has the potential to facilitate the development of computational methods that improve the measurement of cognitive and mental functioning. In three populations (college students, patients with a substance use disorder, and Amazon Mechanical Turk workers), we evaluated one such method, Bayesian adaptive design optimization (ADO), in the area of delay discounting by comparing its test-retest reliability, precision, and efficiency with that of a conventional staircase method. In all three populations tested, the results showed that ADO led to 0.95 or higher test-retest reliability of the discounting rate within 10-20 trials (under 1-2 min of testing), captured approximately 10% more variance in test-retest reliability, was 3-5 times more precise, and was 3-8 times more efficient than the staircase method. The ADO methodology provides efficient and precise protocols for measuring individual differences in delay discounting.