Journal of the Experimental Analysis of Behavior
Resurgence is defined as an increase in the frequency of a previously reinforced target response when an alternative source of reinforcement is suspended. Despite an extensive body of research examining factors that affect resurgence, the effects of alternative-reinforcer magnitude have not been examined. Thus, the present experiments aimed to fill this gap in the literature. In Experiment 1, rats pressed levers for single-pellet reinforcers during Phase 1. In Phase 2, target-lever pressing was extinguished, and alternative-lever pressing produced either five-pellet, one-pellet, or no alternative reinforcement. In Phase 3, alternative reinforcement was suspended to test for resurgence. Five-pellet alternative reinforcement produced faster elimination and greater resurgence of target-lever pressing than one-pellet alternative reinforcement. In Experiment 2, effects of decreasing alternative-reinforcer magnitude on resurgence were examined. Rats pressed levers and pulled chains for six-pellet reinforcers during Phases 1 and 2, respectively. In Phase 3, alternative reinforcement was decreased to three pellets for one group, one pellet for a second group, and suspended altogether for a third group. Shifting from six-pellet to one-pellet alternative reinforcement produced as much resurgence as suspending alternative reinforcement altogether, while shifting from six pellets to three pellets did not produce resurgence. These results suggest that alternative-reinforcer magnitude has effects on elimination and resurgence of target behavior that are similar to those of alternative-reinforcer rate. Thus, both suppression of target behavior during alternative reinforcement and resurgence when conditions of alternative reinforcement are altered may be related to variables that affect the value of the alternative-reinforcement source.
Timeouts are sometimes used in applied settings to reduce target responses, and in some circumstances delays are unavoidably imposed between the onset of a timeout and the offset of the response that produces it. The present study examined the effects of signaled and unsignaled timeouts in rats exposed to concurrent fixed-ratio 1 fixed-ratio 1 schedules of food delivery, where each response on one lever, the location of which changed across conditions, produced both food and a delayed 10-s timeout. Delays of 0 to 38 s were examined. Delayed timeouts often, but not always, substantially reduced the number of responses emitted on the lever that produced timeouts relative to the number emitted on the lever that did not produce timeouts. In general, greater sensitivity was observed to delayed timeouts when they were signaled. These results demonstrate that delayed timeouts, like other delayed consequences, can affect behavior, albeit less strongly than immediate consequences.
Effects of shifts in food reinforcement context on rats’ consumption of concurrently available water or sucrose solution
The purpose of this study was to investigate the effects of signaled transitions from relatively rich to lean conditions of food reinforcement on drinking concurrently available water or sucrose-sweetened water in rats. Past research demonstrated that these negative incentive shifts produce behavioral disruption in the form of extended pausing on fixed-ratio schedules. Four male Long-Evans rats operated on a two-component multiple fixed-ratio fixed-ratio schedule. In one manipulation, the ratio was held constant and the components arranged either a large six-pellet reinforcer (rich) or small one-pellet reinforcer (lean). In a second manipulation, the components both produced a one-pellet reinforcer but differed in terms of the ratio requirement, with the rich and lean conditions corresponding to relatively small and large ratios. In both manipulations, components were pseudorandomly presented to arrange four transitions signaled by retractable levers: lean-to-lean, lean-to-rich, rich-to-rich, and rich-to-lean (the negative incentive shift). During experimental conditions, a bottle with lickometer was inserted in the chamber, providing concurrent access either to tap water or a 10% sucrose solution. The negative incentive shift produced considerably more drinking than the other transitions in all rats during both manipulations. The level of drinking was not polydipsic; rather, it appears that the negative incentive shift enhanced the value of concurrently available reinforcers relative to food reinforcement.
Are positive and negative reinforcement “different”? Insights from a free-operant differential outcomes effect
Although theoretical discussions typically assume that positive and negative reinforcement differ, the literature contains little unambiguous evidence that they produce differential behavioral effects. To test whether the two types of consequences control behavior differently, we pitted money-gain positive reinforcement and money-loss-avoidance negative reinforcement, scheduled through identically programmed variable-cycle schedules, against each other in concurrent schedules. Contingencies of response-produced feedback, normally different in positive and negative reinforcement, were made symmetrical. Steeper matching slopes were produced compared to a baseline consisting of all positive reinforcement. This free-operant differential outcomes effect supports the notion that that stimulus-presentation positive reinforcement and stimulus-elimination negative reinforcement are functionally “different.” However, a control experiment showed that the feedback asymmetry of more traditional positive and negative reinforcement schedules also is sufficient to create a “difference” when the type of consequence is held constant. We offer these findings as a small step in meeting the very large challenge of moving negative reinforcement theory beyond decades of relative quiescence.
In a frequently used suboptimal-choice procedure pigeons choose between an alternative that delivers three food pellets with p = 1.0 and an alternative that delivers ten pellets with p = 0.2. Because pigeons reliably choose the probabilistic (suboptimal) alternative, the procedure has been proposed as a nonhuman analog of human gambling. The present experiments were conducted to evaluate two potential threats to the validity of this procedure. Experiments 1 and 2 evaluated if pigeons obtained food at a lower unit price (i.e., pecks per pellet) on the suboptimal alternative than on the optimal alternative. When pigeons worked under this suboptimal procedure they all preferred the suboptimal alternative despite some pigeons paying a higher price for food on that alternative. In Experiment 2, when the unit price ratio more closely approximated the inverse of the expected value ratio, pigeons continued to prefer the suboptimal alternative despite its economic suboptimality. Experiment 3 evaluated if, in accord with the string-theory of gambling, the valuation of the suboptimal alternative was increased when pigeons misattributed a subset of the suboptimal no-food trials to the optimal alternative. When trial sequences were arranged to minimize these possible attribution errors, pigeons still preferred the suboptimal alternative. These data remove two threats to the validity of the suboptimal choice procedure; threats that would have suggested that suboptimal choice reflects economic maximization.
Despite the success of exposure-based psychotherapies in anxiety treatment, relapse remains problematic. Resurgence, the return of previously eliminated behavior following the elimination of an alternative source of reinforcement, is a promising model of operant relapse. Nonhuman resurgence research has shown that higher rates of alternative reinforcement result in faster, more comprehensive suppression of target behavior, but also in greater resurgence when alternative reinforcement is eliminated. This study investigated rich and lean rates of alternative reinforcement on response suppression and resurgence in typically developing humans. In Phase 1, three groups (Rich, n = 18; Lean, n = 18; Control, n = 10) acquired the target response. In Phase 2, target responding was extinguished and alternative reinforcement delivered on RI 1 s, RI 3 s, and extinction schedules, respectively. Resurgence was assessed during Phase 3 under extinction conditions for all groups. Target responding was suppressed most thoroughly in Rich and partially in Lean. Target responding resurged in the Rich and Lean groups, but not in the Control group. Between groups, resurgence was more pronounced in the Rich group than the Lean and Control groups. Clinical implications of these findings, including care on the part of clinicians when identifying alternative sources of reinforcement, are discussed.
“Watch out!”: Effects of instructed threat and avoidance on human free-operant approach–avoidance behavior
Approach–avoidance paradigms create a competition between appetitive and aversive contingencies and are widely used in nonhuman research on anxiety. Here, we examined how instructions about threat and avoidance impact control by competing contingencies over human approach–avoidance behavior. Additionally, Experiment 1 examined the effects of threat magnitude (money loss amount) and avoidance cost (fixed ratio requirements), whereas Experiment 2 examined the effects of threat information (available, unavailable and inaccurate) on approach–avoidance. During the task, approach responding was modeled by reinforcing responding with money on a FR schedule. By performing an observing response, participants produced an escalating “threat meter”. Instructions stated that the threat meter levels displayed the current probability of losing money, when in fact loss only occurred when the level reached the maximum. Instructions also stated pressing an avoidance button lowered the threat level. Overall, instructions produced cycles of approach and avoidance responding with transitions from approach to avoidance when threat was high and transitions back to approach after avoidance reduced threat. Experiment 1 revealed increasing avoidance cost, but not threat magnitude, shifted approach–avoidance transitions to higher threat levels and increased anxiety ratings, but did not influence the frequency of approach–avoidance cycles. Experiment 2 revealed when threat level information was available or absent earnings were high, but earnings decreased when inaccurate threat information was incompatible with contingencies. Our findings build on prior nonhuman and human approach–avoidance research by highlighting how instructed threat and avoidance can impact human AA behavior and self-reported anxiety.
A second type of magnitude effect: Reinforcer magnitude differentiates delay discounting between substance users and controls
Basic research on delay discounting, examining preference for smaller–sooner or larger–later reinforcers, has demonstrated a variety of findings of considerable generality. One of these, the magnitude effect, is the observation that individuals tend to exhibit greater preference for the immediate with smaller magnitude reinforcers. Delay discounting has also proved to be a useful marker of addiction, as demonstrated by the highly replicated finding of greater discounting rates in substance users compared to controls. However, some research on delay discounting rates in substance users, particularly research examining discounting of small-magnitude reinforcers, has not found significant differences compared to controls. Here, we hypothesize that the magnitude effect could produce ceiling effects at small magnitudes, thus obscuring differences in delay discounting between groups. We examined differences in discounting between high-risk substance users and controls over a broad range of magnitudes of monetary amounts ($0.10, $1.00, $10.00, $100.00, and $1000.00) in 116 Amazon Mechanical Turk workers. We found no significant differences in discounting rates between users and controls at the smallest reinforcer magnitudes ($0.10 and $1.00) and further found that differences became more pronounced as magnitudes increased. These results provide an understanding of a second form of the magnitude effect: That is, differences in discounting between populations can become more evident as a function of reinforcer magnitude.
We propose quantitative experimental approaches to the question of whether positive and negative reinforcement are functionally different, and discuss scientific and ethical concerns that would arise if these approaches were pursued.
Extended pausing during discriminable transitions from rich-to-lean conditions can be viewed as escape (i.e., rich-to-lean transitions function aversively). In the current experiments, pigeons’ key pecking was maintained by a multiple fixed-ratio fixed-ratio schedule of rich or lean reinforcers. Pigeons then were provided with another, explicit, mechanism of escape by changing the stimulus from the transition-specific stimulus used in the multiple schedule to a mixed-schedule stimulus (Experiment 1) or by producing a period of timeout in which the stimulus was turned off and the schedule was suspended (Experiment 2). Overall, escape was under joint control of past and upcoming reinforcer magnitudes, such that responses on the escape key were most likely during rich-to-lean transitions, and second-most likely during lean-to-lean transitions. Even though pigeons pecked the escape key, they paused before doing so, and the latency to begin the fixed ratio (i.e., the pause) remained extended during rich-to-lean transitions. These findings suggest that although the stimulus associated with rich-to-lean transitions functioned aversively, pausing is more than simply escape responding from the stimulus.
Children's preference for mixed- versus fixed-ratio schedules of reinforcement: A translational study of risky choice
Laboratory research has shown that when subjects are given a choice between fixed-ratio and bi-valued mixed-ratio schedules of reinforcement, preference typically emerges for the mixed-ratio schedule even with a larger ratio requirement. The current study sought to replicate and extend these findings to children's math problem completion. Using an ABCBC reversal design, four fourth-grade students were given the choice of completing addition problems reinforced on either a fixed-ratio 5 schedule or one of three mixed-ratio schedules; an equivalent mixed-ratio (1, 9) schedule, a mixed-ratio (1, 11) schedule with a 20% larger ratio requirement, and an equally lean mixed-ratio (5, 7) schedule without the small fixed-ratio 1 component. This was followed by a reversal back to the preceding phase in which preference for the mixed-ratio schedule had been observed, and a final reversal back to the mixed-ratio (5, 7) phase. Findings were consistent with previous research in that all children preferred the mixed-ratio (1, 9) schedule over the equivalent fixed-ratio 5 schedule. Preference persisted for the leaner mixed-ratio (1, 11) schedule for three of the four children. Indifference or preference for the fixed-ratio 5 alternative was observed in phases containing the mixed-ratio (5, 7) schedule. These results extend previous research on risky choice to children's math problem completion and highlight the importance of a small ratio component in the emergence of preference for bi-valued mixed-ratio schedules. Implications of these results for arranging reinforcement to increase children's academic responding are discussed.
BEHAVIOR ANALYSTS IN THE WAR ON POVERTY: A REVIEW OF THE USE OF FINANCIAL INCENTIVES TO PROMOTE EDUCATION AND EMPLOYMENT
Poverty is a pervasive risk factor underlying poor health. Many interventions that have sought to reduce health disparities associated with poverty have focused on improving health-related behaviors of low-income adults. Poverty itself could be targeted to improve health, but this approach would require programs that can consistently move poor individuals out of poverty. Governments and other organizations in the United States have tested a diverse range of antipoverty programs, generally on a large scale and in conjunction with welfare reform initiatives. This paper reviews antipoverty programs that used financial incentives to promote education and employment among welfare recipients and other low-income adults. The incentive-based, antipoverty programs had small or no effects on the target behaviors; they were implemented on large scales from the outset, without systematic development and evaluation of their components; and they did not apply principles of operant conditioning that have been shown to determine the effectiveness of incentive or reinforcement interventions. By applying basic principles of operant conditioning, behavior analysts could help address poverty and improve health through development of effective antipoverty programs. This paper describes a potential framework for a behavior-analytic antipoverty program, with the goal of illustrating that behavior analysts could be uniquely suited to make substantial contributions to the war on poverty.
Simulating demand for cigarettes among pregnant women: A Low-Risk method for studying vulnerable populations
A substantive obstacle to experimentally studying cigarette smoking and use of other tobacco products in pregnant women is the risk of adverse effects on mother and fetus from experimenter administration of the product of interest. The purpose of this study is to investigate bypassing that obstacle by using behavioral economic simulation tasks. In the present study we used the Cigarette Purchase Task (CPT) to simulate changes in demand for hypothetical cigarettes as a function of varying cigarette prices. Participants were 95 pregnant women who completed the CPT prior to participation in a smoking-cessation trial. Aggregate and individual participant demand varied as an orderly function of price and those changes were well fitted by an exponential equation. Demand also varied in correspondence to two well-validated predictors of individual differences in smoking cessation among pregnant women (cigarettes smoked per day, pre-pregnancy quit attempts). Moreover, CPT indices were more effective than these two conventional variables in predicting individual differences in whether women made a quit attempt during the current pregnancy. Overall, these results represent a promising step in demonstrating the validity and utility of the CPT for experimentally examining demand for cigarettes, and potentially other tobacco and nicotine delivery products, among pregnant women.
Pigeons made repeated choices between earning and exchanging reinforcer-specific tokens (green tokens exchangeable for food, red tokens exchangeable for water) and reinforcer-general tokens (white tokens exchangeable for food or water) in a closed token economy. Food and green food tokens could be earned on one panel; water and red water tokens could be earned on a second panel; white generalized tokens could be earned on either panel. Responses on one key produced tokens according to a fixed-ratio schedule, whereas responses on a second key produced exchange periods, during which all previously earned tokens could be exchanged for the appropriate commodity. Most conditions were conducted in a closed economy, and pigeons distributed their token allocation in ways that permitted food and water consumption. When the price of all tokens was equal and low, most pigeons preferred the generalized tokens. When token-production prices were manipulated, pigeons reduced production of the tokens that increased in price while increasing production of the generalized tokens that remained at a fixed price. The latter is consistent with a substitution effect: Generalized tokens increased and were exchanged for the more expensive reinforcer. When food and water were made freely available outside the session, token production and exchange was sharply reduced but was not eliminated, even in conditions when it no longer produced tokens. The results join with other recent data in showing sustained generalized functions of token reinforcers, and demonstrate the utility of token-economic methods for assessing demand for and substitution among multiple commodities in a laboratory context.
This paper examines similarities in the works of Epicurus, an ancient Greek philosopher, and B. F. Skinner, a behavioral psychologist. They both were empiricists who argued in favor of the lawfulness of behavior while maintaining that random events were included within those laws. They both devoted much effort to describing how individuals could live effective, rewarding and pleasurable lives. They both emphasized simple and natural pleasures (or reinforcers) and the importance of combining personal pleasures with actions that benefit friends and community. They both opposed punishment and all aversive measures used by governments and religions to control behaviors. And both created utopias: a real community, The Garden, where Epicurus lived with his followers, and a fictional one, Walden Two, by Skinner. We consider how a combination of the ideas of Epicurus and Skinner can contribute to their common goal of helping people to live better lives.
Stimulus–reinforcer relations established during training determine resistance to extinction and relapse via reinstatement
The baseline rate of a reinforced target response decreases with the availability of response-independent sources of alternative reinforcement; however, resistance to disruption and relapse increases. Because many behavioral treatments for problem behavior include response-dependent reinforcement of alternative behavior, the present study assessed whether response-dependent alternative reinforcement also decreases baseline response rates but increases resistance to extinction and relapse. We reinforced target responding at equal rates across two components of a multiple schedule with pigeons. We compared resistance to extinction and relapse via reinstatement of (1) a target response trained concurrently with a reinforced alternative response in one component with (2) a target response trained either concurrently or in separate components from the alternative response across conditions. Target response rates trained alone in baseline were higher but resistance to extinction and relapse via reinstatement tests were greater after training concurrently with the alternative response. In another assessment, training target and alternative responding together, but separating them during extinction and reinstatement tests, produced equal resistance to extinction and relapse. Together, these findings are consistent with behavioral momentum theory—operant response–reinforcer relations determined baseline response rates but Pavlovian stimulus–reinforcer relations established during training determined resistance to extinction and relapse. These findings imply that reinforcing alternative behavior to treat problem behavior could initially reduce rates but increase persistence.
Evaluating the effects of discriminability on behavioral persistence during and following time-based reinforcement
With four children with autism we evaluated a refinement to time-based reinforcement designed to reduce response persistence when we simultaneously introduced time-based reinforcement and extinction. We further evaluated whether this refinement mitigated response recurrence when all reinforcer deliveries ceased during an extinction-only disruptor phase. The refinement involved increasing the saliency of the contingency change from contingent reinforcement (during baseline) to time-based reinforcement by delivering different colored reinforcers during time-based reinforcement. Behavioral momentum theory predicts that increasing the discriminability of the change from variable-interval to variable-time reinforcement should lead to faster reductions in responding. We present data on four participants, three of whom displayed response patterns consistent with the predictions of behavioral momentum theory during time-based reinforcement. However, the participants showed more varied patterns of recurrent behavior during extinction. We discuss these results within a translational research framework focusing on strategies used to mitigate treatment relapse for severe destructive behavior, as time-based reinforcement is one of the most commonly prescribed interventions for destructive behavior displayed by individuals with intellectual and developmental disabilities.
The Cigarette Purchase Task is a behavioral economic assessment tool designed to measure the relative reinforcing efficacy of cigarette smoking across different prices. An exponential demand equation has become a standard model for analyzing purchase task data, but its utility is compromised by its inability to accommodate values of zero consumption. We propose a two-part mixed effects model that keeps the same exponential demand equation for modeling nonzero consumption values, while providing a logistic regression for the binary outcome of zero versus nonzero consumption. Therefore, the proposed model can accommodate zero consumption values and retain the features of the exponential demand equation at the same time. As a byproduct, the logistic regression component of the proposed model provides a new demand index, the “derived breakpoint”, for the price above which a subject is more likely to be abstinent than to be smoking. We apply the proposed model to data collected at baseline from college students (N = 1,217) enrolled in a randomized clinical trial utilizing financial incentives to motivate tobacco cessation. Monte Carlo simulations showed that the proposed model provides better fits than an existing model. We note that the proposed methodology is applicable to other purchase task data, for example, drugs of abuse.