Association for Behavior Analysis International

As a social species, interactions between individuals are a fundamental aspect of human life. In fact, given how ubiquitous group contingencies are in social settings, they may be greater determinants of behavior in such contexts than contingencies for individual subjects. Thus, an understanding of the antecedents and consequences that govern social interaction is necessary for a comprehensive experimental analysis of human behavior. However, in comparison to the large body of research assessing behavior of individual subjects, relatively less attention has been directed to the experimental analysis of interactions between two or more organisms. For instance, little is known about how selectively reinforcing either coordinated responses (cooperation) or only the first response to meet a given criterion (competition) influences patterns of responding. Furthermore, it is unknown if social stimuli themselves may function as reinforcers. Thus, the four talks in this symposium will explore ways in which social stimuli influence behavior. These will include an assessment of coordinated responding in rats under both fixed-interval (FI) and variable-interval (VI) schedules, an investigation of human coordinated responding under concurrent VI schedules, an analysis of competition under concurrent fixed-ratio (FR) schedules, and an exploration of whether visual-social stimuli can function as reinforcers.

Coordinated responding of two or more organisms can be considered a unit when its consequences change the frequency of its occurrences. Two experiments evaluated coordination under reinforcement schedules. Coordinated responding was defined as lever presses by each rat that occurred within short time interval of one another. Seven dyads of rats served in two experiments. Experiment 1 investigated the effects of Fixed Ratio (FR) schedules on coordinated responding in two groups with increasing FR requirements. In Group 1, dyads of rats worked on adjoining chambers; in Group2, dyads worked on separated chambers. Coordinated responses produced reinforcers to both rats simultaneously (simultaneous reinforcement) in Group 1. In Group 2, each rat had access to reinforcers independently (individual reinforcement) depending on their individual responding. In Experiment 2, dyads worked on adjoining chambers under Fixed and Variable Interval schedules of individual and simultaneous reinforcement. Requirement for defining coordinated responding that produced simultaneous reinforcement were also changed (200, 500, 800milliseconds). Both experiments showed that "pseudo" coordinated responding of the pairs in the individual reinforcement schedules depended on the individual rats’ overall rates, while coordinated responding changed as a unit in the simultaneous reinforcement schedules, assessed by systematic increase in the proportion of coordinated responding.

For over 40 years, concurrent schedules of reinforcement have been used as a procedure to study choice. However, only a few studies have investigated choice when the response unit is the coordinated responses of two or more organisms. In this presentation, we will describe the results of two experiments where pairs of human participants coordinated their responses on concurrent variable-interval (conc VI VI) schedules. In the experiments, each member moved a playing piece, meeting on two corners of the computer screen. Meetings were defined as a coordinated response. In Experiment 1, coordinated responses of three pairs were sensitive to changes in rates of reinforcements and social control. The fourth pair showed control of each other responses, but coordinated responses were insensitive to changes in reinforcement rates. In a follow-up study (Experiment 2), we are further examining the role of social control and leader-follower interactions on the distribution of coordinated responses. We are investigating whether the response of a member is biased by the response distribution of his/her partner. In experiment 2, participants are allowed to choose different corners at a time. We then discuss which variables to consider when describing choices where social control and coordination are required.

Competition describes the behavior of organisms working in opposition for access to reinforcers. Laboratory assessments of competition generally have delivered reinforcers to organisms that respond faster than their opponents. Little attention has been directed to how the competition contingency influences behavior. Thus, the purpose of the present experiment was to compare behavior resulting from selectively reinforcing a sequence of responses that was either faster or slower than that of an opponent. Eight male White Carneau pigeons were subjected to a fixed-ratio (FR) 30 schedule of reinforcement. After stable baselines were established, pairs of subjects were exposed to competitive FR 30 schedules with 30 trials per session. Only the subject that first completed the FR earned reinforcement. Once stability was attained, or earlier following a decline in performance, an adjusting handicap was added. Faster or slower completion of the FR respectively increased or decreased the ratio requirement on the next trial. Subsequently the contingency was reversed so that slower completion of the FR was reinforced while faster completion was not. Preliminary results suggest that response rates increased upon introduction of the rapid competition contingency, and further increased with the FR handicap. No systematic changes in post-reinforcement pause durations have been observed.

Visual-social stimuli were presented contingent on key-pecking responses to determine the conditions under which access to social stimuli may function as a reinforcer. A two-compartment operant chamber was used to house a pigeon in the right compartment and a standard 60-watt lightbulb in the left compartment. Compartments were separated by a two-way mirror. When the lightbulb was illuminated the mirror became transparent and the interior of the left compartment could be seen from the right. When the light was darkened the mirror became reflective and the left compartment could not be seen. Two keys were in the right compartment. Completion of a fixed-ratio (FR) schedule on the left key darkened the lightbulb for 10 s, producing a reflection of the pigeon in the right compartment and, thus, simulating the presence of conspecific. Responses on the right key produced 3-s access to food according to a variable-interval (VI) schedule. Primary dependent measures were response rates on the left and right keys. Various experimental conditions, including systematic manipulations of the schedules on each key, were conducted to investigate contexts in which visual-social stimuli acted as reinforcers when an alternate source of food reinforcement was concurrently available.