Sex differences in the social motivation of rats: Insights from social operant conditioning, behavioural economics, and video tracking.

BACKGROUND: Social behaviour plays a key role in mental health and wellbeing, and developing greater understanding of mechanisms underlying social interaction-particularly social motivation-holds substantial transdiagnostic impact. Common rodent behavioural assays used to assess social behaviour are limited in their assessment of social motivation, whereas the social operant conditioning model can provide unique and valuable insights into social motivation. Further characterisation of common experimental parameters that may influence social motivation within the social operant model, as well as complementary methodological and analytical approaches, are warranted. METHODS: This study investigated the effects of biological sex, housing condition, and time-of-day, on social motivation using the social operant model. This involved training rats to lever press (FR1) for 60-s access to a social reward (same-sex conspecific stimulus). Subjects were male and female Wistar rats, housed under individual or paired conditions, and sessions were conducted either in the mid-late light phase (ZT6-10) or early-mid dark phase (ZT13-17). A behavioural economics approach was implemented to measure social demand and the influence of stimulus partner sex (same- vs. opposite-sex stimulus) on social operant responding. Additionally, video tracking analyses were conducted to assess the degree of convergence between social appetitive and consummatory behaviours. RESULTS: Biological sex, housing conditions, the interaction between sex and housing, and stimulus partner sex potently influenced social motivation, whereas time-of-day did not. Behavioural economics demonstrated that sex, housing, and their interaction influence both the hedonic set-point and elasticity of social demand. Video analysis of social interaction during social operant sessions revealed that social appetitive and consummatory behaviours are not necessarily convergent, and indicate potential social satiety. Lastly, oestrus phase of female experimental and stimulus rats did not impact social motivation within the model. CONCLUSIONS: Social isolation-dependent sex differences exist in social motivation for rats, as assessed by social operant conditioning. The social operant model represents an optimal preclinical assay that comprehensively evaluates social motivation and offers a platform for future investigations of neurobiological mechanisms underlying sex differences in social motivation. These findings highlight the importance of continued consideration and inclusion of sex as a biological variable in future social operant conditioning studies. Humans are social creatures-our everyday interactions with others and the support this provides play a key role in our wellbeing. For those experiencing mental health conditions, people's motivation to engage with others can wane, which can lead them to withdraw from those who support them. Therefore, to develop better treatment strategies for these conditions, we need to gain a deeper understanding of social motivation. Studying social behaviour in animals can facilitate this investigation of social motivation as it allows for a causal understanding of underlying neurobiology that is not possible in human experiments. An optimal way to study social motivation in animals is using the social operant conditioning model, where rats learn to press a lever that opens a door and allows them to interact with another rat for a short time. This study characterised the social operant model by testing whether sex, housing conditions, time-of-day, and the sex of the stimulus partner influence rats' motivation to seek interaction with another rat. We found that female rats were more socially motivated than males, and that rats living alone were more motivated than those living with another rat; interestingly, this effect of housing affected females more than males. Regardless of sex, rats were more motivated to interact with a rat of the opposite sex. These findings provide insights into sex differences in social motivation in rats and new insights into the social operant model which will help guide future research into social motivation and other mental health conditions.

Behavioral Economics to Enhance Food Is Medicine Programs.

This Viewpoint highlights ways in which behavioral economics could enhance Food Is Medicine programs in the US.

Nudge theory and gambling: a scoping review.

Background: Gambling disorder (GD) is a pressing public health concern with significant societal costs. The recently developed nudge theory, which is rooted in behavioral economics, aims to influence the decision-making behaviors of individuals by implementing changes in the environment. Aim: This scoping review aims to synthesize the literature on nudge theory as it relates to gambling. Methods: This scoping review accords with the Arksey and O'Malley framework, as refined by Levac et al. It includes only articles from peer-reviewed journals that focus, as main themes, on both nudge theory and gambling. The final study selection includes six articles. Results: The scoping review process led to studies explaining how (1) nudges aim to prod people toward healthier gambling choices, fostering the adoption of more responsible gambling practices, and (2) some gambling features, called dark nudges (or sludges), exploit and harm the decision-making processes of people who gamble. Conclusion: This scoping review highlights the fact that many stakeholders are involved in the field of gambling, and that better cooperation between them would promote safer and more responsible gambling practices. Future research is also needed to empirically test nudges to develop a better understanding of their impact on those who gamble.

Foraging in a non-foraging task: Fitness maximization explains human risk preference dynamics under changing environment.

Changes in risk preference have been reported when making a series of independent risky choices or non-foraging economic decisions. Behavioral economics has put forward various explanations for specific changes in risk preference in non-foraging tasks, but a consensus regarding the general principle underlying these effects has not been reached. In contrast, recent studies have investigated human economic risky choices using tasks adapted from foraging theory, which require consideration of past choices and future opportunities to make optimal decisions. In these foraging tasks, human economic risky choices are explained by the ethological principle of fitness maximization, which naturally leads to dynamic risk preference. Here, we conducted two online experiments to investigate whether the principle of fitness maximization can explain risk preference dynamics in a non-foraging task. Participants were asked to make a series of independent risky economic decisions while the environmental richness changed. We found that participants' risk preferences were influenced by the current and past environments, making them more risk-averse during and after the rich environment compared to the poor environment. These changes in risk preference align with fitness maximization. Our findings suggest that the ethological principle of fitness maximization might serve as a generalizable principle for explaining dynamic preferences, including risk preference, in human economic decision-making.

Self-management behavior strategy based on behavioral economics in patients with hypertension: a scoping review.

Hypertensive patients often do not make the most favorable choices and behaviors for managing disease. Behavioral economics strategies offer new ideas for guiding patients toward health behavior. The scoping review aimed to summarize behavioral economics strategies designed to improve hypertension self-management behaviors. A literature search was conducted in September 2022 using the following electronic databases: Embase, Medline, CINAHL, PsycINFO, Web of Science, Cochrane Library, CNKI, Wan Fang Database for Chinese Periodicals, and CBM-SinoMed. We screened the literature for experimental studies written in Chinese or English reporting on BE strategies designed to improve self-management behavior in hypertension. We searched 17 820 records and included 18 articles in the final scoping review. We performed qualitative synthesis by the categories of choice architecture. The most common BE strategies were those targeting decision information and decision assistance, such as changing the presentation of information, making information visible, and providing reminders for actions. Most strategies targeted BP, diet, medication adherence, and physical activity behavior. Ten out of 18 studies reported statistically significant improvement in self-management behavior. Further research on BE strategies should focus on addressing the challenges, including changing the decision structure, encompassing a more comprehensive range of target behaviors, and examining the long-term effects of BE strategies.

Self-management of hypertension is a long-term effort, but people often make bounded rational decisions and act in ways that deviate from health goals. Behavioral Economics (BE) strategies make small changes in the decision-making environment to alter choices, steering individuals' behavior consistent with their goals or preferences. We summarized the BE strategies to improve self-management behavior in hypertension and described the study results using the categories of choice architecture. We found that the most widely used BE strategy is changing the presentation of information in the decision-making environment. Most BE strategies positively affect the target behaviors, which have the potential of BE strategies to enhance self-management behavior for hypertension. Further research is needed to identify the origins of these strategies, modify decision-making structures, and incorporate a broader range of health behaviors to showcase the practicality and sustainability of implementing BE strategies.

How does the frame of communication affect cancer patients' decisions?-from a behavioral economics point of view.

BACKGROUND: It has been said that physicians should provide their patients with accurate evidence in terms of information on treatment options. However, in some cases, although the physician provides accurate and sufficient information, the patient still chooses the medically not-recommended treatment. The purpose of this research is to clarify how patients' decisions differ when a physician changes the frame of an explanation when he/she provides information about cancer treatment. METHODS: An online questionnaire survey was conducted in March 2017. Through the aid of a survey company, we emailed questionnaires to 1,360 cancer patients who received treatment within the last 2 years. We randomly assigned participants to 6 hypotheticals scenario of a terminal cancer patient, and presented hypothetical evidence in different ways. Subsequently, we asked survey participants whether they would choose to receive additional anti-cancer treatment. RESULTS: Although there was no statistically significant difference between scenarios, the "social burden" groups showed a lower rate of patients who preferred to continue a medically ineffective anti-cancer treatment than the control group, at a 10% significance level. The scenario significantly affected the patients' sense of abandonment [F(5, 1,354)=5.680, P<0.001], sense of distress [F(5, 1,354)=3.920, P=0.002], and necessity of improvement [F(5, 1,354)=2.783, P=0.017]. CONCLUSIONS: Nudges were not shown to be effective in situations where discontinuation of anticancer treatment was being considered. On the other hand, some nudges were found to be invasive and should be used with caution.

Xylazine does not enhance fentanyl reinforcement in rats: A behavioral economic analysis.

The adulteration of illicit fentanyl with the alpha-2 agonist xylazine has been designated an emerging public health threat. The clinical rationale for combining fentanyl with xylazine is currently unclear, and the inability to study fentanyl/xylazine interactions in humans warrants the need for preclinical research. We studied fentanyl and xylazine pharmacodynamic and pharmacokinetic interactions in male and female rats using drug self-administration behavioral economic methods. Fentanyl, but not xylazine, functioned as a reinforcer under both fixed-ratio and progressive-ratio drug self-administration procedures. Xylazine combined with fentanyl at three fixed dose-proportion mixtures did not significantly alter fentanyl reinforcement as measured using behavioral economic analyses. Xylazine produced a proportion-dependent decrease in the behavioral economic Q0 endpoint compared to fentanyl alone. However, xylazine did not significantly alter fentanyl self-administration at FR1. Fentanyl and xylazine co-administration did not result in changes to pharmacokinetic endpoints. The present results demonstrate that xylazine does not enhance the addictive effects of fentanyl or alter fentanyl plasma concentrations. The premise for why illicitly manufacture fentanyl has been adulterated with xylazine remains to be determined.

How can a behavioral economics lens contribute to implementation science?

BACKGROUND: Implementation science in health is an interdisciplinary field with an emphasis on supporting behavior change required when clinicians and other actors implement evidence-based practices within organizational constraints. Behavioral economics has emerged in parallel and works towards developing realistic models of how humans behave and categorizes a wide range of features of choices that can influence behavior. We argue that implementation science can be enhanced by the incorporation of approaches from behavioral economics. Main body First, we provide a general overview of implementation science and ways in which implementation science has been limited to date. Second, we review principles of behavioral economics and describe how concepts from BE have been successfully applied to healthcare including nudges deployed in the electronic health record. For example, de-implementation of low-value prescribing has been supported by changing the default in the electronic health record. We then describe what a behavioral economics lens offers to existing implementation science theories, models and frameworks, including rich and realistic models of human behavior, additional research methods such as pre-mortems and behavioral design, and low-cost and scalable implementation strategies. We argue that insights from behavioral economics can guide the design of implementation strategies and the interpretation of implementation studies. Key objections to incorporating behavioral economics are addressed, including concerns about sustainment and at what level the strategies work. CONCLUSION: Scholars should consider augmenting implementation science theories, models, and frameworks with relevant insights from behavioral economics. By drawing on these additional insights, implementation scientists have the potential to boost efforts to expand the provision and availability of high quality care.

A behavioral economics approach to enhancing HIV preexposure and postexposure prophylaxis implementation.

PURPOSE OF REVIEW: The 'PrEP cliff' phenomenon poses a critical challenge in global HIV PrEP implementation, marked by significant dropouts across the entire PrEP care continuum. This article reviews new strategies to address 'PrEP cliff'. RECENT FINDINGS: Canadian clinicians have developed a service delivery model that offers presumptive PEP to patients in need and transits eligible PEP users to PrEP. Early findings are promising. This service model not only establishes a safety net for those who were not protected by PrEP, but it also leverages the immediate salience and perceived benefits of PEP as a natural nudge towards PrEP use. Aligning with Behavioral Economics, specifically the Salience Theory, this strategy holds potential in tackling PrEP implementation challenges. SUMMARY: A natural pathway between PEP and PrEP has been widely observed. The Canadian service model exemplifies an innovative strategy that leverages this organic pathway and enhances the utility of both PEP and PrEP services. We offer theoretical insights into the reasons behind these PEP-PrEP transitions and evolve the Canadian model into a cohesive framework for implementation.

Role of relative-reinforcement value of alcohol-free activities during recovery from alcohol use disorder in an adult clinical sample.

Behavioral economic theory has been extensively applied to understand alcohol use disorder (AUD). Applications of behavioral economic theory conceptualize AUD as a pattern of harmful alcohol use over extended periods of time in which choices between drinking or engaging in alcohol-free activities favor drinking. Recovery, in contrast, entails a sustained shift toward a pattern of selecting rewarding alcohol-free activities. The present study examined whether alcohol-free activity engagement and the relative-reinforcement value (RRV) of engaging in those activities predicted AUD treatment outcomes via secondary analysis of data from Project MATCH, a multisite randomized clinical trial examining behavioral treatments for AUD (N = 1,279, 75.8% male, 81.0% non-Hispanic White, 9.5% Black, 7.7% Hispanic/Latino, 1.5% American Indian/Alaska Native, < 1% Asian American, and other race/ethnicity). Regression analyses indicated that every additional alcohol-free activity reported at 6 months posttreatment was associated with 7% fewer drinking days, 5% fewer heavy drinking days, and approximately one less drink per drinking day, as well as with significant improvements in depression, purpose in life, and psychosocial functioning at 12 months following treatment. Consistent with behavioral economic theory, higher RRV of alcohol-free activities also predicted significant reductions in drinking and improvements in functioning, and these associations were stronger compared to results for alcohol-free activity frequency only. The findings highlight the importance of understanding environmental contexts conducive to recovery and support the value of increasing alcohol-free activity engagement and the RRV of engaging in such activities to facilitate reductions in drinking and improved functioning among individuals with AUD. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Behavioral economic and wellness-based approaches for reducing alcohol use and consequences among diverse non-student emerging adults: study protocol for Project BLUE, a randomized controlled trial.

BACKGROUND: Emerging adults (EAs) who are not 4-year college students nor graduates are at elevated risk for lifetime alcohol use disorder, comorbid drug use, and mental health symptoms, compared to college graduates. There is a need for tailored brief alcohol intervention (BAI) approaches to reduce alcohol risk and to facilitate healthy development in this high-risk population. Most BAIs include a single session focused on discussing risks associated with drinking and correcting normative beliefs about drinking rates. EAs may benefit from additional elements that enhance general wellness. The substance-free activity session (SFAS) aims to clarify life goals and values and increase goal-directed activities that provide alternatives to alcohol use, and the relaxation training (RT) session teaches relaxation and stress reduction skills. METHODS: The present study is a randomized 3-group (BAI + SFAS vs. RT + SFAS vs. education control) trial with 525 EAs (175 per group; estimated 50% women and 50% African American) who report recent risky drinking and who are not students or graduates of 4-year colleges. Participants will have the option of completing the intervention sessions in person or via a secure video teleconference. Levels of drinking and alcohol-related problems will be evaluated at baseline and 1, 3, 6, and 12 months post-intervention. The primary hypothesis is that both BAI + SFAS and RT + SFAS participants will report significantly greater reductions in alcohol use and problems relative to education control participants, with no differences in outcomes between the two active treatment conditions. DISCUSSION: The results of this study will inform alcohol prevention efforts for high-risk community dwelling emerging adults. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT04776278.

A Behavioral Economic Examination of Sexual Behaviors in the Era of Pre-exposure Prophylaxis via Explanatory Sequential Mixed Methods.

Pre-exposure prophylaxis (PrEP) use may be associated with condom use decisions. The current investigation examined sexual decision-making in the context of PrEP among young adult men who have sex with men (MSM) between 18 and 30 years old, using an explanatory sequential mixed methods design. For the quantitative aim, 99 MSM currently taking PrEP (i.e., PrEP-experienced) and 140 MSM not currently taking PrEP (i.e., PrEP-naive) completed an online survey, including the Sexual Delay Discounting Task (SDDT), which captures likelihood of condom use. For the qualitative aim, 15 people from each group were interviewed about their (1) conceptualizations of risky sex and (2) ways they manage their sexual risk. Participants were, on average, 25.69 years old (SD = 3.07) and 64% White. Results from the quantitative aim revealed, controlling for covariates, PrEP-experienced participants exhibited significantly lower likelihood of (1) using an immediately available condom and (2) waiting for a delayed condom (i.e., sexual delay discounting) compared to PrEP-naive participants. Qualitative themes explaining what young adult MSM consider to be risky sex included: (1) any sex as risky sex, (2) risky sex as "sex without a conversation," and (3) risky sex as sex with risk for physical harm. Themes on ways young adult MSM manage sexual risk were classified as proactive, reactive, and passive. Results suggest that PrEP use is related to condom use decisions. Taken together, quantitative differences in sexual delay discounting, but qualitatively similar conceptualizations and management of risky sex, suggest that the SDDT may be a useful tool in sex research to capture processes (i.e., delay discounting) underlying sexual decision-making that may be missed by traditional self-reports. Implications of results, including potentially providing (good quality) condoms with every PrEP prescription, and future research topics are discussed.

Efficacy of Behavioral Economic Nudges to Assist Teen Mothers: the Healthy Adolescent Transitions Randomized Controlled Trial.

Communities may often lack the resources to deliver intensive programs to assist teen mothers, and many eligible adolescents may decline participation in lengthy interventions. Therefore, alternative approaches involving less resource and time may be needed. Behavioral economics (BE) can inform the development of such novel interventions. BE often feature low-intensity approaches designed to "nudge" people to help them reach their long-term goals. Nudges can include giving reminders, making the desired behavior more convenient, and optimizing the verbal presentation of recommended options. Three hundred thirty-one American adolescents (ages 14 to 19) who were 22 to 35 weeks pregnant were enrolled in the present trial. One hundred sixty-six participants were randomly assigned to the intervention condition featuring a three-month BE intervention delivered by a registered nurse and social worker. The remaining 165 youths were assigned usual care. Surveys were completed at baseline, 3 months, 12 months, and 18 months. Data collection occurred from 2017 to 2021. Qualitative feedback indicated that the BE intervention was well-received by adolescents. However, there were no significant differences between the intervention and control groups at any time point regarding repeat pregnancy, contraceptive usage, financial literacy, school completion, job attainment, HPV vaccinations, nicotine usage, perception of having a medical home, urgent care/ED usage, and nutritional intake (all p > .05). Our findings suggest that a BE-based intervention may not be sufficient to facilitate change for teen mothers. Future programs should consider lasting longer, featuring a higher dose, and/or incorporating systems-level changes. This trial was prospectively registered (NCT03194672 clinicaltrials.gov).

Behavioral Economic Incentives to Support HIV Care: Results From a Randomized Controlled Trial in Uganda.

BACKGROUND: This study tests behavioral economics incentives to improve adherence to antiretroviral treatment (ART), with 1 approach being low cost. SETTING: Three hundred twenty-nine adults at Mildmay Hospital in Kampala, Uganda, on ART for at least 2 years and showing adherence problems received the intervention for about 15 months until the study was interrupted by a nation-wide COVID-19 lockdown. METHODS: We randomized participants into 1 of 3 (1:1:1) groups: usual care ("control" group; n = 109) or 1 of 2 intervention groups where eligibility for nonmonetary prizes was based on showing at least 90% electronically measured ART adherence ("adherence-linked" group, n = 111) or keeping clinic appointments as scheduled ("clinic-linked"; n = 109). After 12 months, participants could win a larger prize for consistently high adherence or viral suppression. Primary outcomes were mean adherence and viral suppression. Analysis was by intention-to-treat using linear regression. This trial is registered with ClinicalTrials.gov, NCT03494777 . RESULTS: Neither incentive arm increased adherence compared with the control; we estimate a 3.9 percentage point increase in "adherence-linked" arm [95% confidence interval (CI): -0.70 to 8.60 ( P = 0.10)] and 0.024 in the "clinic-linked" arm [95% CI: -0.02 to 0.07 ( P = 0.28)]. For the prespecified subgroup of those with initial low adherence, incentives increased adherence by 7.60 percentage points (95% CI: 0.01, 0.15; P = 0.04, "adherence-linked") and 5.60 percentage points (95% CI: -0.01, 0.12; P = 0.10, "clinic-linked"). We find no effects on clinic attendance or viral suppression. CONCLUSIONS: Incentives did not improve viral suppression or ART adherence overall but worked for the prespecified subgroup of those with initial low adherence. More effectively identifying those in need of adherence support will allow better targeting of this and other incentive interventions.

Confusion cannot explain cooperative behavior in public goods games.

Some scholars find that behavioral variation in the public goods game is explained by variations in participants' understanding of how to maximize payoff and that confusion leads to cooperation. Their findings lead them to question the common assumption in behavioral economics experiments that choices reflect motivations. We conduct two experiments, in which we minimize confusion by providing participants with increased training. We also introduce a question that specifically assesses participants' understanding of payoff maximization choices. Our experimental results show that the distribution of behavior types is significantly different when participants play with computers versus humans. A significant increase in contributions is also observed when participants play with humans compared to when they play with computers. Moreover, social norms may be the main motive for contributions when playing with computers. Our findings suggest that social preferences, rather than confusion, play a crucial role in determining contributions in public goods games when playing with humans. We therefore argue that the assumption in behavioral economics experiments that choices reveal motivations is indeed valid.

Longitudinal examination of alcohol demand and alcohol-related reinforcement as predictors of heavy drinking and adverse alcohol consequences in emerging adults.

BACKGROUND AND AIMS: Behavioral economic theory predicts that high alcohol demand and high proportionate alcohol-related reinforcement are important determinants of risky alcohol use in emerging adults, but the majority of research to date has been cross-sectional in nature. The present study investigated prospective and dynamic relationships between alcohol demand and proportionate alcohol-related reinforcement in relation to heavy drinking days and alcohol problems. DESIGN: Longitudinal cohort with assessments every 4 months for 20 months. SETTING: Ontario, Canada. PARTICIPANTS: Emerging adults reporting regular heavy episodic drinking (n = 636, Mage = 21.44; 55.8% female). MEASUREMENTS: Heavy drinking days (HDD; Daily Drinking Questionnaire), alcohol problems (Brief Young Adult Alcohol Consequences Questionnaire), alcohol demand (Alcohol Purchase Task) and proportionate alcohol-related reinforcement (Activity Level Questionnaire). FINDINGS: Linear mixed effects models revealed that behavioral economic indicators and alcohol-related outcomes significantly decreased over the study, consistent with 'aging out' of risky alcohol use. Random intercept cross-lagged panel models revealed significant between-person relationships, such that higher alcohol demand and alcohol-related reinforcement were positively associated with HDD and alcohol problems (random intercepts = 0.187-0.534, Ps < 0.01). Moreover, alcohol demand indicators (particularly the rate of change in elasticity of the demand curve, as measured by α, and the maximum expenditure, Omax) and proportionate alcohol-related reinforcement significantly forecasted changes in HDD at all time points (|ßs| = 0.063-0.103, Ps < 0.05) in cross-lagged relationships, with bidirectional associations noted for the rate of change in elasticity (ßs = -0.085 to -0.104, Ps < 0.01). Proportionate alcohol-related reinforcement also significantly forecasted changes in alcohol problems at all time points (ßs = 0.072-0.112, Ps < 0.01). CONCLUSIONS: Multiple behavioral economic indicators (demand elasticity, maximum expenditure and reinforcement ratio) forecast changes in heavy episodic drinking and alcohol problems over the course of emerging adulthood. These results further implicate alcohol demand and proportionate alcohol-related reinforcement as etiologically and developmentally important mechanisms in alcohol use trajectories.