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Two pigeons that were previously exposed to a multiple schedule of reinforcement in the presence of a stuffed and a live pigeon, and two of three naive pigeons, responded on a mirror during exposure to multiple fixed‐ratio, fixed‐ratio schedules of reinforcement for key pecking. Both the topography and temporal pattern of mirror responding were comparable to schedule‐induced “attack” on live and stuffed targets. Rate of target responding was reduced when either the mirror was covered with paper or when the multiple schedule was removed. A reversal in the relationship between reinforcement schedules and discriminative stimuli demonstrated that mirror responding was controlled by the stimulus correlated with the higher fixed‐ratio schedule. With one component of the multiple schedule held constant at fixed ratio 25 and the ratio requirement of the other component varying from 25 to 150, there was an inverted U‐shaped relationship between rate of mirror responding and fixed‐ratio schedule in the varied component. As in Flory's study (1969b) there was an inverted U‐shaped relationship between target responding and inter‐food intervals. The combined results of these studies suggest that the relationship between rate of target responding and reinforcement schedules is controlled primarily by the inter‐food intervals resulting from the schedules.

Pigeons were exposed to seven types of two‐component schedules, each component a 2‐min fixed‐interval schedule. Food presentation occurred at the completion of the second component under all conditions. The seven types of schedules were: (1) a chained schedule in which completion of the first component produced the discriminative stimulus associated with the second component; (2) a chained schedule to which was added the brief presentation of a food‐paired stimulus at the completion of the first component; (3) a chained schedule to which was added the brief presentation of a stimulus not paired with food at the completion of the first component; (4) a multiple schedule in which food presentation occurred at the completion of both components; (5) a tandem schedule in which completion of the first component initiated the second component, with no changes in exteroceptive stimuli; (6) a food‐paired brief‐stimulus schedule in which the brief presentation of a food‐paired stimulus was made at the completion of the first component and no other changes in stimuli occurred; and (7) a brief‐stimulus schedule in which the brief presentation of a stimulus not paired with food was made at the completion of the first component and no other changes in stimuli occurred. Positively accelerated patterns of responding developed in the first component under three conditions: (1) the chained schedule with the added food‐paired brief stimulus; (2) the multiple schedule; and (3) the food‐paired brief‐stimulus schedule. Response rates were low in the first component, with few instances of positively accelerated patterns, under two conditions: (1) the chained schedule; and (2) the chained schedule with the added nonpaired brief stimulus. The results suggest that a briefly presented food‐paired stimulus may function as a more effective conditioned reinforcer than does the presentation of a discriminative stimulus.

Nine adolescent boys with a history of high rates of disruptive classroom behavior were selected from a psychiatric hospital school and placed in a remedial reading class after school in which various factors in a token reinforcement program involving self‐evaluation were investigated. The effects of self‐evaluation, in the form of a rating the students gave themselves about the appropriateness of their classroom behavior, were first assessed. While the students' ratings of their own behavior correlated highly with the teacher's ratings and evaluations made by independent observers, the self‐evaluations did not lead to a reduction in disruptive behavior. A token reinforcement program, in which the teacher rated the students' level of appropriate behavior and in which the students traded earned rating points for prizes, clearly led to a reduction of disruptive behavior. When the students were given the opportunity to evaluate their own behavior and to receive rewards in exchange for the evaluation, they returned to their former rates of disruptive behavior.

Self‐imposed timeouts by pigeons working under a progressive‐ratio food schedule were studied under different conditions. The main findings were (1) continued production of timeouts over an extended series of sessions, (2) more frequent responding on the key with the timeout consequence than on a key having no consequence, (3) an inverse relationship between number of timeouts and level of body weight, (4) production of timeouts when the timeout duration was brief, lengthy, or controlled by the pigeon, and (5) dependence of self‐imposed timeouts on variables controlling responding under the progressive‐ratio schedule. Under all experimental conditions, with the exception of performances at the high body weight, timeouts were more frequent during the longer progressive‐ratio steps and usually were localized in the post‐reinforcement pause or the early part of the step. The timeout behavior could be interpreted as either an escape from aversive stimuli generated by the progressive‐ratio schedule or as a response reinforced by the consequent stimulus change.