|Responding Under Ratio Schedules of Reinforcement: What Causes the Pause?
|Monday, May 26, 2008
|10:30 AM–11:50 AM
|Area: EAB; Domain: Basic Research
|Chair: Henry D. Schlinger (California State University, Los Angeles)
|CE Instructor: Henry D. Schlinger, Ph.D.
This symposium will 1) discuss the historical roots of research into the variables responsible for pausing on ratio schedules of reinforcement, including the use of multiple and mixed schedules to assess the relative influence of events that precede and follow the pause; 2) present recent research further clarifying the roles of conditioned inhibitory effects of reinforcement and of varying ratio size and reinforcer magnitude in multiple fixed-ratio schedules; and 3) discuss the implications of what we know about the causes of the ratio pause for behavioral interruptions in humans, such as procrastination and neglect
|Post-reinforcement or Pre-ratio Pause: What’s in a Name?
|HENRY D. SCHLINGER (California State University, Los Angeles)
|Abstract: In The Behavior of Organisms and, most notably, in Schedules of Reinforcement, Skinner maintained that the zero rate of responding after reinforcement on fixed-ratio (FR) schedules was controlled by the S-delta effects of the reinforcer — hence the term “post-reinforcement pause.” Subsequently, researchers demonstrated the influence of such variables as ratio size, reinforcement magnitude, and response effort on post-reinforcement pausing. Much of what is known about pausing under ratio schedules, however, has come from performances on simple schedules, which hold fixed characteristics such as the ratio size and reinforcer magnitude. The problem posed by using simple schedules is that pausing could just as easily be attributed to the upcoming rather than the preceding ratio. The solution is to use multiple or mixed schedules. Many studies using multiple and mixed FR schedules have in fact shown that pausing is also influenced by stimuli correlated with the upcoming ratio, which has led some researchers to use the term “pre-ratio pause.” This talk will briefly trace the development of research on pausing from Skinner’s first experiments to contemporary studies, emphasizing how changing from simple to multiple schedules has led to a better understanding of the ratio pause.
|Fixed-Ratio Schedules of Reinforcement: The Role of Conditioned Inhibition in Pausing.
|ADAM DERENNE (University of North Dakota), Kathryn A. Flannery (University of North Dakota)
|Abstract: A well-known feature of performances under fixed-ratio schedules of reinforcement is the appearance of a pause in responding that occurs following the delivery of each reinforcer. This pause is often of such a duration that it cannot be readily attributed to the time required for subjects to consume the reinforcer or any other obvious need of the subject. One popular explanation for why pausing occurs is that the beginning of each ratio is correlated with the immediate unavailability of additional reinforcement and the resulting conditioned inhibition temporarily suppresses responding. In several experiments with rats and mice we examined how conditioned inhibition is affected by the use of explicit stimuli correlated with reinforcer unavailability and by the delivery of noncontingent reinforcers early in the ratio. The results suggest that conditioned inhibition alone cannot explain the origins of fixed-ratio pausing.
|Interactive Effects of Response Requirements and Reinforcer Magnitude on Fixed-Ratio Pausing.
|JESSICA B. LONG (West Virginia University), Harold E. Lobo (West Virginia University), Michael Perone (West Virginia University)
|Abstract: Pigeons responded on multiple schedules with components differing in both the size of the fixed ratio required for food reinforcement (access to grain) and the magnitude of the reinforcement (duration of the access). The ratio requirement and reinforcer magnitude were manipulated across conditions to effect “rich” and “lean” components. In some cases the lean component was made increasingly leaner (by raising the ratio requirement or lowering the reinforcer magnitude) across conditions. In other cases the rich component was enriched (by lowering the ratio requirement or increasing reinforcer magnitude) across conditions. Pausing was analyzed in each of the four possible transitions from one component to the next: rich-to-rich, rich-to-lean, lean-to-rich, and lean-to-lean. Pausing was extended in the rich-to-lean transition when the there was a sufficient difference between the two components. This effect was intensified when the difference between components was created by leaning the lean component rather than enriching the rich component. The worsening of local conditions may not be sufficient to generate pausing; the context in which this worsening occurs must also be considered.
|Why Pausing Matters.
|MICHAEL PERONE (West Virginia University)
|Abstract: Pausing, as measured in operant conditioning experiments, represents an interruption in the behavioral stream of interest. The study of pausing may shed light on basic behavioral processes – for example, why a schedule of reinforcement may temporarily lose control over behavior – and provide insights into the cause and cure of human problems that involve behavioral interruptions, such as procrastination, neglect, and other forms of irresponsibility. In this talk I will summarize some of the causes of pausing and some of the possible applications of this knowledge.