Association for Behavior Analysis International

In a delay discounting experiment, an organism is subjected to two choices: a small, immediate reinforcer and a larger, delayed reinforcer. Following the delivery of the reinforcer, an inter-trial-interval (ITI) occurs. Despite its delay, the large reinforcer is optimal as it produces the highest amount of rewards, and expressing a preference for the small reinforcer is therefore considered a measure of impulsivity. We tested the Spontaneously Hypertensive Rat, an animal model of ADHD, on a modified version of this approach in a pilot experiment. The rats were split into two groups: in one group, the response-reinforcer delay was increased for each session, while in another group the ITI increased instead, corresponding in length to the delay in the first group. We found that the rats in the Delay group showed a decreased preference for the larger reinforcer as the trial length increased, but the rats in the ITI group did not show this pattern. This suggests that the rats were sensitive to response-reinforcer delays, but not the length of the inter-trial-interval or the trial length as a whole. This suggests that using compensating designs on animals in delay discounting is problematic.

Recent research with adult humans indicates that selfish choice in a social dilemma task is correlated with degree of social discounting (Jones & Rachlin, 2009). The present study extends this research to children and adolescents by modifying both the social dilemma and social discounting tasks. In the social dilemma task, participants were presented with a choice between their wallet and their friend’s piggy bank. A participant who chose the wallet received either (a) 100 yen or (b) 300 yen; a participant who chose the piggy bank received either (a) 0 yen or (b) 200 yen. Choosing the wallet is regarded as selfish, whereas choosing the piggy bank is regarded as altruistic. The amount a participant received (a or b) was determined by their friend’s choice. If the friend’s choice was selfish, amount-a was received; if the friend’s choice was altruistic, amount-b was received. In the social discounting task, participants were presented with a series of choices between hypothetical rewards of their own or sharing with other people. In the delay discounting task, participants were presented with a series of choices between hypothetical rewards of immediate or delayed. Preliminary analysis of 1076 participants, ages 6-14 years, suggests that the selfishness in the social dilemma task, social discounting rate, and delay discounting rate decreased as a function of age. Results of the participants' social-discounting and delay-discounting tasks are also discussed.

College students are exhibiting decreasing patterns of physical activity; and in turn, a greater rate of negative health outcomes after college. Interestingly, the degree to which one discounts the subjective value of delayed rewards (i.e. delay discounting) is related to physical activity and healthy dieting. Efforts to improve one's physical appearance, a subcategory of body image investment, is also linked to greater levels of physical activity and healthy dieting. To our knowledge, no research has evaluated how delay discounting and body image may jointly relate to physical activity. In the current study, forty-six undergraduates reported physical activity, completed a delay discounting task, and indicated the percentage of a hypothetical cash allotment ($1,000) that they would spend on achieving their own ideal body image. Results showed that lower rates of delay discounting and a higher percentage valuation of ideal body image independently predicted PA during the previous week and during a typical week. The current study suggests the importance of examining motivational factors such as body image in conjunction with delay discounting to better understand the initiation and maintenance of physical activity.

Understanding factors that influence impulsivity in young people is important in reducing risky decision making and behavior. Impulsivity can be measured through direct measures (behavioral tasks), and indirect measures (self-report scales). This study investigated the relationship between direct and indirect measures of impulsivity and their association with age. Participants (67 females, 27 males; M= 24.38 years, range= 16-71 years) completed the Barratt Impulsivity Scale (BIS-11), the Brief Sensation Seeking Scale (BSSS) and a delay discounting task. Data showed that scores on the BIS-11 or the BSSS were not significantly correlated with the indifference points from the delay discounting task at any of the six delays. Age was not significantly correlated with the indifference points, or with the BIS-11. Sensation seeking (BSSS) was negatively correlated with age (r(92)=-.259, p=.013). Thus, direct and indirect measures of impulsivity do not give the same results. The next phase will examine the influence of peers on decisions in the delay discounting task.

The purpose of this paper is to evaluate the hyperbolic temporal discounting function in university students and to evaluate the effect of stress coping strategies and social skills in the form of the hyperbolic function of the temporary discount. The sample consisted of 98 students enrolled in the psychology program of Health Sciences, with a mean age of 21.5 years (SD = 3.22), 75 women (76.5%). The following instruments were administered: Modified Coping Strategies Scale (Londoño et al., 2006), Reactive and Proactive Aggression Questionnaire (Andreu, Peña and Ramírez, 2009). The adjusting amount discounting task consisted of presenting to the participants two hypothetical rewards options, one immediately available (adjustable condition with initial value of $ 2000) and another larger reward (fixed condition of $ 4000) available after delays that ranged from one month to eight years. Students who employ stress coping strategies such as tolerating the stressful situation through the control of emotions present smaller discount rate. Students who indicate concern about the expression of positive feelings and the initiation of interactions with the opposite sex present a higher discount rate. Similarly, students who are more afraid of expressing positive feelings present a higher rate of discount to future rewards.

Delay discounting refers to the decrease in the subjective value of a reward as a function of the time to its receipt, and steeper discounting rates have been shown to be related to obesity. It has been argued that delay-discounting rates of consumable rewards depend on their caloric value and on the participant's body mass index (BMI) or body-fat percentage (BFP). To assess the contribution of reward type and health indexes, 64 teenagers chose between pairs of various hypothetical amounts of money, water, soda, healthy food, and fast food, one amount of each that was smaller but would be received immediately and another, larger amount of that reward that would be received later. An adjusting-amount procedure was used to determine the indifference point at each of seven delays to each of the larger reward amounts. We obtained participants' BMI and BFP and divided them in low-weight, normal-weight, overweight, and obesity groups, and low-BFP, acceptable-BFP, high-acceptable-BFP and very-high-BFP groups, respectively. Globally, the AuC's were low and similar for money and water, and higher for fast food, healthy food, and soda, for the two lower health indexes. However, the AuC was variable and not related with the two higher health indexes.

Social discounting refers to the decrease in the willingness of an individual to give a reward to another person as the social distance between them increases. As a parametric extension to social discounting, we evaluated the degree of social discounting in which the person can choose to forego a given amount of money in order to give it to one of two persons who are at different social distances from each other and at different social distances from the choosing person. One-hundred seventeen participants were exposed to four conditions of a social-discounting task which consisted of a series of choices between a smaller reward for a socially closer person and a larger reward for a socially farther person. The social distance between both persons, as well as that between the participant and the closer person, was manipulated within and between conditions. Participants showed higher social-discounting rates as the social distance between the nearer and the farther persons increased. These findings extend the study of social discounting and suggest that altruistic and selfish behaviors depend on the social distance between the choosing person and the receivers of the benefit, as well as on the distance between possible receivers.

Previous researchers have investigated how choices change based on the absolute magnitude of an outcome (e.g. Green et al., 1999). However, no studies have investigated how choices change as a function of magnitude relative to the amount in a participant's bank. We investigated how endowing participants with a bank of varying amounts influenced choice within probability discounting tasks. 60 undergraduate psychology students completed four discounting tasks. Each task presented one of two absolute magnitudes for the uncertain alternative (i.e., $3,000 and $500,000). Additionally, each task presented one of four bank amounts (i.e., 1/4 or 4 times the absolute magnitude). This resulted in four magnitude combinations: small absolute magnitude/small relative to the bank (SA/SR); small absolute magnitude/large relative to the bank (SA/LR); large absolute magnitude/small relative to the bank (LA/LR); large absolute magnitude/large relative to the bank (LA/LR). In the ascending condition, participants prioritized the magnitude relative to the bank amount (i.e., discounting small outcomes relative to bank amount less steeply than large outcomes relative to bank amount). In the descending condition, participants prioritized the absolute magnitude (i.e. discounting small absolute outcomes less steeply than large absolute outcomes). Our results suggest endowed bank amounts can influence participants' choices under uncertain conditions.

Delays to reinforcement are often a necessary component during treatments of challenging behavior (e.g., Functional Communication Training; FCT). In the absence of programmed delay training, the utility and generality of FCT may be limited. Despite the importance of delays to reinforcement during FCT, few studies have empirically isolated and investigated the parameters pertaining to the implementation of delays to reinforcement. Results from basic empirical studies have shown that variable delays, or bi-valued mixed delays to reinforcement, are preferred in humans and nonhuman studies. The current research examined response allocation between fixed and mixed delays to reinforcement using a concurrent schedule of reinforcement. Results showed a preference for mixed delays to reinforcement with 2 out of 6 participants and no preference between delay arrangements for the remaining 4 participants. Potential avenues of future research on the use of mixed delays to reinforcement, such as the application within FCT and maintenance of socially appropriate behaviors, are discussed.

To study self-controlled behavior, three main procedures have been used: choice, resistance to "temptation," and delay of gratification. In general, these procedures involve choosing between pairs of rewards of different magnitude and delay of delivery, or refraining from taking an available reward until a predetermined waiting criterion is met. These procedures capture three apparently different aspects or dimensions of self-controlled behavior. Therefore, to examine the interaction between these procedures would be useful to advance our understanding of the dimensions of self-controlled behavior. With this purpose, 18 undergraduate students were exposed to each procedure following different sequences of exposure to them. The participants were exposed to each procedure for three consecutive sessions; the main dependent variable was the obtention of the delayed rewards (SR2). The participants initially exposed to the choice procedure virtually obtained all the SR2 programmed in the three procedures. Participants initially exposed to resistance to "temptation" showed more self-controlled behavior compared to participants initially exposed to delay of gratification. It is suggested that the initial exposure to a procedure may act as a "training" for the following procedure.

Altruism, in a behavioral sense, can be defined as "costly acts that confer economic benefits on other individuals" (Fehr & Fischbacher, 2003). One factor that seems to impact the likelihood of an individual behaving altruistically is what is known as social distance. Jones and Rachlin (2006) found that people will forgo an amount of money to keep for themselves in order to give a larger amount of money to another person, with the amounts of money forgone varying systematically as a function of social distance. There is limited research suggesting music could influence altruistic behavior, but nothing that directly examines altruism through a social discounting paradigm. The goal of the present study was to determine if music could indeed have some impact on altruistic behavior, and more specifically, if an individual's particular music preferences could have an impact on their respective rates of social discounting. Participants were undergraduates at the University of Nevada, Reno. To obtain individual music preferences, two questionnaire tasks were utilized. Each participant experienced three conditions: 1) no music, 2) preferred music, and 3) non-preferred music followed by three versions of a social discounting questionnaire. Results indicate that music does seem to have an impact on rates of social discounting. Participants were more likely to confer hypothetical money to those further away in social distance, rather than keep it for themselves, after hearing a song that they indicated as preferred. The order of music presentation was also a factor. Those who heard their non-preferred song first, were less likely to give away money to someone more socially distant than those participants that heard their preferred song first.

Previous research has shown that performing repetitive tasks requiring self-control, such as regular exercise, is an effective strategy for improving impulsivity. This study compared the changes in impulsivity among college students across three fitness classes, which were different in terms of type and total time of exercise. In the high intensity fitness class (n=38), students engaged in muscular exercise at least 3 times a week for an hour and a half per day. In the moderate intensity class (n=25), students had to exercise once a week for 2 hours. In the low intensity class (n=27), students participated in any sports activities including basketball, tennis or squash once a week for an hour and a half. A delay discounting task was administered at the beginning and the end of a semester to measure the changes in impulsivity. The differences among three classes were evaluated by repeated measures analysis of variance. Results revealed no significant difference in changes of impulsivity across three classes. The results suggest that exercise does not improve impulsivity, which is not consistent with early findings. Further studies with larger sample sizes or randomized controlled trials are needed to explore how exercise influences impulsivity.

The purpose of the present work was to study the effects of varying delay and reinforcement magnitude in ascending and descending order on response rate. Three studies were conducted to explore the possibility that varying the order of exposure to reinforcement magnitude and delay of reinforcement modulate self-controlled or impulsive behavior. Two studies included experimental subjects and one with a teenager engaged in problem behavior. Experiment 1 examined the joint effects of delay of reinforcement and reinforcement magnitude on response rate in rats. Subjects exposed to reinforcement delays in ascending order showed greater self-controlled behavior than those in descending order. Experiment 2 showed the well-known effect of delayed reinforcement on the response rate, as delay of reinforcement was greater response rate decreased. Experiment 3 was a study included the participation of an adolescent who had been referred for the functional analysis and treatment of problem behavior (i.e., aggression, disruption and substance abuse). The general procedure included reduce reinforcement magnitude if any problem behavior persists. Response rate for aggression, disruption and substance abuse decreased significantly compared to base line. The findings are discussed in the relevance of interaction between experimental analysis of behavior and applied behavior analysis.

Impulsive behavior (aka, impulsivity) has been defined as a preference for smaller-immediate rewards over larger-delayed rewards. Impulsivity is a hallmark of many behavioral and psychiatric disorders including ADHD, pathological gambling, substance abuse, bipolar disorder, and others. A common variable in impulsive behavior across the lifespan is the inability to forego immediate consequences for delayed consequences. Delay discounting refers to the decrease in the subjective value of a reward based on delays, and provides an empirically-validated framework for assessing and measuring impulsive behavior in humans as well as non-humans. In a typical delay-discounting experiment, individuals are asked to choose between a smaller reward available immediately and a larger reward available after a delay. Effort discounting refers to the decrease in the subjective value of rewards as the effort required to obtain the rewards increases. In a typical effort discounting task, individuals are asked to choose between a low-effort reward and a high-effort reward. The present study assessed impulsive behavior using both the delay and effort discounting frameworks. Preliminary results include similar patterns of responding between the two behavioral measures, and a positive correlation between effort and delay discounting. However, more data will be needed for more conclusive results.

There has been much research looking at various disorders and diseases considered to be "impulse" driven; for example, additions (e.g., alcohol, gambling, cigarette, etc.) or mental health (e.g., depression, anxiety, bi-polar disorder, etc.). However, there has been less research looking at more-simple characteristics such as home ownership, education, or income level. The current study will evaluate at various demographic factors and their relation to the k-value, or degree of discounting. Based on prior research, it is known that overall degree of discounting decreases with age, but the current study will also evaluate whether this change is due to simple maturation or other variables that correlate with changes in age. Based on preliminary results, there appear to be decreases in the k-value based on additional variables (i.e., income, education, children, and home ownership); however, more data will be needed to make more conclusive inferences. One application of these results includes helping employers to design more attractive benefits package to fit their employees based on relevant demographics.