The present study used a delay discounting task and the Valued Living Questionnaire to examine the relationship between delay discounting and self-reported values. Thirty-eight participants completed the study. Participants were asked to make choices between immediate and delayed monetary rewards to determine rates of discounting. An exponential function (R2=0.97) provided a strong fit for discounting scores. On the Valued Living Questionnaire, participants rated on a Likert-type scale of 1-10 both the importance and their action in the previous week toward the following values: Family, marriage, parenting, friends, work, education, recreation, spirituality, community, and physical well-being. A composite valued living scored was calculated and compared to participant discounting rates; results suggest that there was a significant relationship between participant valued living scores and K-values (p<0.01) and participant valued living scores and AUC (p<0.02). The results of this study, while preliminary, are important for beginning to understand how values impact decision making.

The purpose of this study was to determine the effects of whether pounds are being lost or gained on the rate at which people discount the value of weight change outcomes, as well as determine the effects of whether pounds are being lost or gained and diet length on the value of access to higher calorie foods relative to weight change outcomes. This was accomplished by repeatedly asking participants to choose between two dietary options of the same length but which resulted in gaining or losing a certain number of pounds. Each question varied the length of the diet, how many pounds could be gained or lost, and whether those pounds were being gained when they chose the higher calorie diet or lost when they chose the lower calorie diet. The survey was administered with 30 participants. Whether pounds per being gained or lost did not have a significant effect on the rate at which weight change outcomes were discounted (t = 1.883, p = .07), but did have a significant effect on how many pounds needed to be at stake per day in order for the participant to choose the lower calorie diet (t = 4.995, p < .01). There was also a significant correlation between diet length and how many pounds needed to be at stake per day in order for the participant to choose the lower calorie diet (ρ = -.373, p <.01). The current investigation has implications for our understanding of choice and discounting behavior, and has specific implications for people who wish to make healthier dietary decisions.

AN ABSTRACT OF THE THESIS OF Katelyn Louise Decker, Master of Science Degree in Behavior Analysis and Therapy, presented on April 30, 2015, at Southern Illinois University TITLE: EFFECTS OF GAMBLING OUTCOMES ON LEVEL OF IMPULSIVITY MAJOR PROFESSOR: Dr. Mark R. Dixon The effects of exposure to winning and losing gambling outcomes on levels of impulsivity among non-gamblers were investigated in a within-subjects experimental design with randomization of treatment phases. Participants included 20 non-gamblers (10 male, 10 female), 18 years or older, selected from a sample of 40 volunteers who completed the South Oaks Gambling Screen (Lesieur & Blume, 1987) and received a score of 0, indicating no predictors of potential pathological gambling. Dependent measures of levels of impulsivity were recorded using an abbreviated version of the delayed discounting questionnaire described by Dixon et al. (2003). Derived k-values were calculated by fitting indifference points at each delay to the hyperbolic equation proposed by Mazur (1987) and average k-value was calculated for each participant across delays. Participants were exposed to both winning and losing outcomes by completing 25 trials within a slot-machine task programmed in Microsoft Visual Basic Express Edition 2008 (Maclin, et al., 2006, p. 127-154). Results were subjected to statistical analysis to determine whether a statistically significant, functional relationship existed between increases and decreases in level of impulsivity (k-value) in comparison to baseline. Across all participants, regardless of order of experimental conditions, results indicated a more than 26% decrease (-82.20-3133.33) in level of impulsivity (0-2.1694) following a losing outcome and a more than 24% decrease (-89.95-3300) in level of impulsivity (0-2.1694) following a winning outcome in comparison to baseline (0-2.3056). Results are consistent with the hypothesis that exposure to winning outcomes decrease impulsivity, but inconsistent with the hypothesis that exposure to losing outcomes increase impulsivity. Historical perspectives of pathological gambling, social impacts of gambling disorder, and trait and state-dependent perspectives of impulsivity are discussed. Potential implications for further research using delayed discounting measures are provided, as well as potential limitations of the present study. Keywords: gambling, impulsivity, delayed discounting, slot-machine, outcomes

The present study examined the effects of a brief video-led mindfulness exercise on momentary choice impulsivity as measured by a monetary delay discounting survey. Participants in the experimental group watched a video requiring them to engage in a brief breathing exercise while participants in the control group viewed a video unrelated to the topics at hand. Switch point analyses suggested that the experimental group discounted less steeply following the intervention while the discounting slope of the control group remained relatively unchanged. A t-test comparing the average change in AUC values from pre-test to post-test for both groups revealed a significant difference: t (13.17) = 2.94, p = 0.0114. The experimental group demonstrated greater changes in AUC scores from pretest to posttest (M= 0.1036 ± 0.0328) than the control group (-0.00031 ± 0.01317). Additionally, an F-test was conducted to compare variances between the individual score changes of the experimental group and the control group (p < .05). The results suggest that there was a significant difference between the two groups: F = 5.682, p = 0.0082. The results of this study could have several implications for future research regarding delay discounting and mindfulness as an intervention for impulsivity and suggest that telecommunication may be a viable modality.

The purpose of the current study is to measure whether delay discounting and impulsivity will differentiate between smokers and non-smokers. It is important to extend upon previous research to understand the effects of antecedent control of delay discounting and impulsivity. Research on this subject is important in developing effective interventions for impulsive behavior like smoking cigarettes. Two surveys were provided to participants: The Monetary Choice Questionnaire (MCQ-27) and the Barratt Impulsivity Scale (BIS-11). An unpaired t test was used to interpret results. Neither the MCQ-11 nor the BIS-11 had a significant difference. Further analysis was conducted comparing age differences using unpaired and paired t tests. There was significant data to support that self-ratings of impulsive behavior differed with age comparisons in the BIS-11. Smokers (ages 26-28) were more impulsive than non-smokers (ages 22-28), and smokers (ages 20-29) showed no statistical significance when compared to smokers (ages 52-68). The MCQ-27 did not show a significant difference in overt impulsive behavior.

Discounting is a behavioral analytic approach that focuses on the assumption that the value of a reward is increasingly discounted as the delay until or the odds against receiving the reward increase. Up to date, there are no studies that have looked at discounting with health care. The current study evaluated the relationship between increasing the cost of the emergency room and time willing to wait to seek medical attention for flu-like symptoms. A discounting task was given to 30 students at a Midwestern university. Results demonstrated that participants indicated that all participants demonstrated an Area Under Curve (AUC) value of less than .01, indicating that there were high levels of impulsivity. Correlational tests were conducted to assess response differences between gender, age and policy holder status. Overall, results demonstrated that as the cost of the emergency room increases, participants were willing to delay seeking medical attention. A hyperbolic function produced a strong fit for this study (R² = 0.95). Due to the population utilized for this study, most of the participants had available health insurance. A future extension of this study would be conducting this discounting task with individuals who do not have health insurance.

Psychopharmacological studies have implicated the mesolimbic dopamine (DA) system in the mediation of cost/benefit evaluations about effort-related costs associated with larger rewards. However, the role of DA in risk-based decision making remains relatively unexplored. The present study investigated how systemic manipulations of DA transmission affect risky choice assessed with a probabilistic discounting task. Over discrete trials, rats between two levers; a press on the “small/certain” lever always delivered one reward pellet, whereas a press on the other, “large/risky” lever delivered four pellets, but the probability of receiving reward decreased across the four trial blocks (100%, 50%, 25%, 12.5%). In separate groups of well-trained rats we assessed the effects of the DA releaser amphetamine, as well as receptor selective agonists and antagonists. Amphetamine consistently increased preference for the large/risky lever; an effect that was blocked or attenuated by co-administration of either D₁ (SCH23390) or D₂ (eticlopride) receptors antagonists. Blockade of either of these receptors alone induced risk aversion. Conversely, stimulation of D₁ (SKF81297) or D₂ (bromocriptine) receptors also increased risky choice. In contrast, activation of D₃ receptors with PD128,907 induced risk aversion. Likewise, D₃ antagonism with nafadotride potentiated the amphetamine-induced increase in risky choice. Blockade or stimulation of D₄ receptors did not reliably alter patterns of choice. These findings indicate that DA plays a critical role in mediating risk-based decision making, where increased activation of D₁ and D₂ receptors biases choice towards larger, probabilistic rewards, whereas D₃ receptors appear to exert opposing effects on this form of decision making. / Arts, Faculty of / Psychology, Department of / Graduate

TITLE: DELAY DISCOUNTING AND CAMPUS SPEEDING BEHAVIORMAJOR PROFESSOR: Dr. Ryan Redner Speeding, as defined by exceeding the speed limit posted in a designated area, is a problem that has a direct negative effect on a majority of America, college campuses not being exempt. A minimal amount of research has been conducted on specifically dangerous driving such as speeding on university campuses; this paper looks to expand upon the existing research. In addition, this study serves the purpose of attempting to correlate speeding and impulsivity. This was achieved by utilizing a survey in conjunction with delay discounting scenarios embedded within. Participants (n = 89) took a survey that involved questions about demographic information and past driving. The survey also included two hypothetical scenarios that encouraged participants to answer whether they would speed in the presented scenarios and at what point. To complete the survey the MCQ (Monetary Choice Questionnaire) was placed at the end. To assess the results the 89 participants were split into two groups two different times to be analyzed. One group was split into an impulsive group and non-impulsive group while the other group was split into speeders and non-speeders. As expected, both the impulsive and speeders were more likely to discount speed at a faster rate; this shown at higher rates in the penalty hypothetical scenario. The implications of this study include that those with that display higher impulsivity, shown through k-values, may have a higher tendency to engage in dangerous driving such as speeding, as well as understanding that penalty conditions, such as point loss, show a correlation with speeding.

The present study sought to evaluate whether a brief ACT session which utilized values and committed action activities was effective in changing how student veterans responded on two different discounting surveys. Participants in experimental and control groups completed a monetary temporal discounting survey and a death probability discounting survey before and after completing either a brief ACT session or completing a control activity. Twenty-three student veterans participated in the present study and a pre-, post-group control group design was utilized to evaluate the effects of the intervention. Independent t-tests were conducted, and the results of those analyses showed that ACT was effective in decreasing discounting on the monetary temporal discounting survey (t(10) = 1.997, p = 0.0368) when compared to the control group (t(11) = 0.2088, p = 0.4192). However, there were no statistically significant changes on the death probability survey in the ACT group (t(10) = 0.2459 p = .4504) or control group (t(11) = 0.8784, p = 0.1992). Implications of these findings and future research are discussed.

The purpose of the current study is to evaluate the relationship between discounting immediate and former life statuses prior to death related to quality of life across the lifespan. A discounting survey was completed by 83 participants in which they were asked to make hypothetical choices regarding returning back to an age they preferred or remaining at their current age prior to dying. In addition, participants completed surveys measuring quality of life, death depression, and death anxiety. Results indicated that participants who reported low quality of life and experienced high depression and anxiety towards death responded more impulsively to the discounting survey, engaging in steeper discounting. Additionally, results indicated that a positive correlation between participants aged 30 to 50 years old and AUC exists, indicating that as age increases, impulsivity decreases. However, this same trend was not evident in participants over the age of 65, yielding no correlation. Strengths and limitations, implications of the current study’s findings, and opportunities for future research are discussed.