Past research has shown that preference for a stimulus is correlated positively with reinforcer efficacy – more preferred stimuli tend to be more potent reinforcers. Researchers have recently examined the use of progressive ratio (PR) reinforcement schedules to evaluate preference. However, research on the concordance between preference and performance under a progressive ratio schedule is limited. Therefore, two experiments were conducted to extend this research. In Experiment 1 I compared the relative reinforcing efficacy of six stimuli obtained under a PR schedule to the mean preference hierarchy obtained through paired-stimulus preference assessments conducted before and after PR reinforcement sessions. In Experiment 2 I evaluated the PR schedule for quantifying the reinforcing value of three stimuli from Experiment 1 (i.e., one high, one medium, and one low preference stimulus). The results of Experiment 1 indicated that items that yielded higher breaking points and responses per minute were also more preferred. However, concordance between percent preference and breaking points and response rates for less preferred items was more variable. The results of Experiment 2 showed that high preference stimuli increased responding over baseline for all participants. However, low preference reinforcers also increased responding over baseline for some participants.

Past research has shown that preference for a stimulus is correlated positively with reinforcer efficacy – more preferred stimuli tend to be more potent reinforcers. Researchers have recently examined the use of progressive ratio (PR) reinforcement schedules to evaluate preference. However, research on the concordance between preference and performance under a progressive ratio schedule is limited. Therefore, two experiments were conducted to extend this research. In Experiment 1 I compared the relative reinforcing efficacy of six stimuli obtained under a PR schedule to the mean preference hierarchy obtained through paired-stimulus preference assessments conducted before and after PR reinforcement sessions. In Experiment 2 I evaluated the PR schedule for quantifying the reinforcing value of three stimuli from Experiment 1 (i.e., one high, one medium, and one low preference stimulus). The results of Experiment 1 indicated that items that yielded higher breaking points and responses per minute were also more preferred. However, concordance between percent preference and breaking points and response rates for less preferred items was more variable. The results of Experiment 2 showed that high preference stimuli increased responding over baseline for all participants. However, low preference reinforcers also increased responding over baseline for some participants.

Important advancements have been made in the identification of reinforcers over the past decade. The use of preference assessments has become a systematic way to identify preferred events that may function as reinforcers for an individual's behavior. Typically, preference assessments require participants to select stimuli through verbal surveys or engagement with stimuli as preferred or non-preferred. Not all studies go on to directly test the effects of the preferred stimuli, and even fewer studies directly test for the effects of the non- preferred stimuli. The present study systematically identified preferred and non-preferred stimuli in adult human subjects by verbal report and then proceeded to test the effects of both verbally reported preferred and non preferred events on single and concurrent schedules of reinforcement. The results are discussed in terms of contemporary concerns regarding preference and reinforcer assessments.

Health behaviors, positive and negative, can support or reduce risk for multiple chronic diseases, such as substance use disorder and obesity. These diseases are marked by overconsuming commodities that offer predictable short-term benefits, and neglecting other behaviors with variable long-term benefits (e.g., fast food is enjoyable in the moment; exercise may have delayed benefits, but moment-to-moment may not be as reinforcing as fast food). An individual's valuation of these fast food or exercise may depend on how far out into the future these benefits are considered, their temporal window. The first study shows that the temporal window is constricted among high-risk substance users than people who do not have substance problems, especially when considering higher-value choices. The second study shows that the temporal window can change depending on the environment. Specifically, engaging with stories of job loss can constrict the temporal window. The third study shows that engaging with job loss can specifically constrict the temporal window and increase the value of fast food among obese individuals. The final study shows that a similar hardship scenario, natural disasters, can constrict the temporal window, increase demand for alcohol and cigarettes, and decrease the valuation of more temporally extended reinforcers (e.g., employment, savings, and seatbelt wearing) among smoking drinkers. Together, these studies support a model, reinforcer pathology; wherein the temporal window, which can differ both between individuals and environments, drives valuation of reinforcers that impact health. / Doctor of Philosophy / Health behaviors, positive and negative, can support or reduce risk for multiple chronic diseases, such as substance use disorder and obesity. These diseases are marked by overconsuming commodities that offer predictable short-term benefits, and neglecting other behaviors with variable long-term benefits (e.g., fast food is enjoyable in the moment; exercise may have delayed benefits, but moment-to-moment may not be as reinforcing as fast food). An individual’s valuation of these fast food or exercise may depend on how far out into the future these benefits are considered, their temporal window. The first study shows that the temporal window is constricted among high-risk substance users than people who do not have substance problems, especially when considering higher-value choices. The second study shows that the temporal window can change depending on the environment. Specifically, engaging with stories of job loss can constrict the temporal window. The third study shows that engaging with job loss can specifically constrict the temporal window and increase the value of fast food among obese individuals. The final study shows that a similar hardship scenario, natural disasters, can constrict the temporal window, increase demand for alcohol and cigarettes, and decrease the valuation of more temporally extended reinforcers (e.g., employment, savings, and seatbelt wearing) among smoking drinkers. Together, these studies support a model, reinforcer pathology; wherein the temporal window, which can differ both between individuals and environments, drives valuation of reinforcers that impact health.

Behavioral momentum theory states that resistance to change of operant behavior is governed by the Pavlovian stimulus-reinforcer relation in a given discriminative stimulus situation. That is, higher reinforcer rates in the presence of a discriminative stimulus result in a stronger stimulus-reinforcer relation and, thereby, greater resistance to change. Within the momentum-based quantitative framework of resistance to change, the construct relating persistence to pre-disruption reinforcer rates is termed “behavioral mass.” All research on which momentum theory is based has examined resistance to change following prolonged exposure to stable reinforcer rates in multiple schedules of reinforcement. Thus, at present little is known about the time frame over which behavioral mass accumulates or the manner by which newly experienced stimulus reinforcer relations are incorporated into mass when these rates change. The experiments described in this dissertation aimed to clarify these facets of the construct. Chapters 1 and 2 provide a detailed overview behavioral momentum theory and resistance to change. Topics discussed include quantitative models of resistance to change, clinical implications of resistance-to-change research, some notable limitations of behavioral momentum theory, and extensions of the theory to account for diverse behavioral outcomes. A recently published study is presented in Chapter 3 that aimed to determine how resistance to change and behavioral mass of pigeons’ key pecking adapts in the face of stimulus-reinforcer relations that change across time during baseline. Results suggest that resistance to change is a function of recently experienced stimulus-reinforcer relations and that behavioral mass depends most heavily on these recent experiences. The experiment described in Chapter 4 extended the findings reported in Chapter 3 by examining whether behavioral mass changes during operant extinction. Pre-exposure to extinction in an alternative multiple-schedule component decreased resistance to extinction of target-component key pecking relative to conditions without pre-exposure to extinction. Between-condition differences in extinction were well accounted for quantitatively by either variation in behavioral mass or changes in the magnitude of factors that are assumed to disrupt responding during extinction. Chapter 5 offers an integrative discussion of this research and emphasizes theoretical implications, practical applications, and areas for future research.

Motivating individuals with autism can be challenging for clinicians and educators seeking to increase skills or decrease problem behaviors. Even when highly preferred reinforcers have been identified, they tend to lose their effectiveness over time. Over the years, several strategies have been developed to maintain the effectiveness of reinforcers. Reinforcer variation has been demonstrated to attenuate decreases in responding associated with repeated exposure to a single reinforcer. Another strategy that has been used to help maintain responding is allowing an individual a choice among reinforcers. Several researchers have suggested that providing choice among several reinforcers may produce the same effects on responding as reinforcer variation. Although these two procedures have been shown to maintain motivation in individuals with autism, they have not been systematically compared and evaluated against each other. In this study, we evaluated the effects of reinforcer variation as compared to reinforcer choice.

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While preference assessments are effective at identifying potential reinforcers, they consume large amounts of time and resources. Multiple variations have been developed in order to save time and money when conducting assessments such as briefer versions, pictorial formats, and verbal formats. The purpose of this study was to examine the efficacy of three different brief MSWO procedures at identifying effective reinforcers for children with developmental disabilities. The procedures of the current study examined a tangible brief MSWO procedure which provided access to the edibles, a pictorial brief MSWO procedure which provided access to the edibles, and a pictorial brief MSWO procedure which did not provide access to edibles. After hierarchies from all three assessments were identified, reinforcer assessments were conducted to determine the efficacy of highly preferred stimuli. Results indicated that all three formats were able to identify effective reinforcers, with similar hierarchies produced for three out of four participants.

The purpose of this study was to expand on research by evaluating the effects of response interruption redirection and response cost alone to reduce vocal stereotypy and to evaluate whether response cost increases the effectiveness of response interruption redirection. Treatment phases included response interruption redirection, response cost, and response interruption redirection plus response cost. We saw high rates of vocal stereotypy during baseline, toy baseline, and pre-intervention phases. During all treatment phases, we saw substantial decreases in stereotypy. For two of the three participants response interruption redirection and response cost was a slightly more effective treatment suggesting that using response interruption redirection with an additive of response cost may further suppress stereotypy. These results were replicated across phases. For one participant response interruption redirection was the most effective treatment. All three treatments reduced vocal stereotypy to clinically acceptable levels for two participants. For one participant, there was only a slight decrease in stereotypy when RC was implemented. We discuss limitations and areas for future research.

The current study consisted of two experiments, both of which were comparisons of choice conditions replicated across four participants. Four typically-developing pre-school children participated in this study. Experiment 1 evaluated participants' preference for choosing consequent stimuli prior to engaging in academic tasks (pre-session choice) versus choosing consequent stimuli each time criterion for reinforcement had been met within the session (within-session choice). In Experiment 2, preference for choice-making was evaluated when outcomes for both choice and no-choice conditions were identical. For two participants, results indicated strong preference for choice-making.