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Twenty‐three pigeons were subjected to a series of procedures in which the key‐peck's effects ranged from immediate, differential food reinforcement, through delayed reinforcement, the production of stimulus changes with and without probable secondary reinforcement, the prevention of food presentation (“food‐avoidance”), to extinction. Neither primary nor secondary food reinforcement appeared to be essential for the maintenance or acquisition of key pecking. The food‐avoidance contingency failed to suppress responding in any subject. Only complete extinction, when pecking produced neither food nor stimulus changes, eliminated all pecking for most subjects. A combination of stimulus‐change reinforcement and food reinforcement appeared to account for the results, but only if it could be assumed that the presence of food in a procedure enhanced the reinforcing power of stimulus change, whether or not the food was also dependent upon responding. Such an interaction between reinforcers may be involved in the phenomenon of auto‐shaping.

A good‐behavior game was implemented in a fifth‐grade reading class consisting of two groups of 14 students each. After the presentation of the game, reversal and component analysis phases were instituted. Game components included rules, lights (response feedback), and group consequences of extra recess and extra free time. Student observers recorded the dependent variables which included talking‐out, disruptive, and out‐of‐seat behaviors. The results show that the game reduced the dependent measures from their baseline rate by almost 99% for one group and 97% for the other. The component analysis revealed that after association in the game, the stimulus components of rules and lights were effective in reducing the dependent behaviors.

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High‐speed photography was used to compare the pigeon's response to unsignalled shock with the pigeon's key‐peck response. During shock, pigeons flex their neck (i.e., the distance between their eyes and shoulders decreases). Following shock, the neck is extended. During key pecking, the neck remains extended and the head moves toward the key in a slight arc as though attached to a fixed fulcrum. Response topography during pecking and shock appear to be incompatible, and it is concluded that the difficulty in key‐peck training pigeons to escape electric shock is due to interference from the unconditioned flexion response. This conclusion supports the species‐specific defense theory of escape and avoidance behavior.

Rats were exposed to schedules in which reinforcement was contingent upon the emission of a 1.0‐ to 2.0‐sec interresponse time. The rate of emission and the temporal distribution of this interresponse time was recorded. Several different contingencies between the emission of the interresponse time and reinforcement were examined. Both the rate of emission and the temporal distribution of the 1.0‐ to 2.0‐sec interresponse time varied as a function of the schedule on which it was reinforced. This finding, which suggests that an interresponse time behaves as other operants, has implications for the analysis of conventional reinforcement schedules in terms of the differential reinforcement of interresponse times.

An inexpensive, easily managed token economy was used in a normal classroom for one academic year, and data were collected for the entire academic performance in spelling, language, handwriting, and math for that year. During a baseline period, assignment completion was variable. The introduction of a token economy with a point exchange every five days increased assignment completion and decreased variability of performance. An application of a token economy that had a point exchange averaging four days was accompanied by an assignment completion rate that approximated 100%. A reinforcement contingency for which quiet behavior rather than for assignment completion was eased quiet behavior was accompanied by a marked diminution of assignment completion. A reintroduction of the token reinforcement for assignment completion system increased assignment completion again.

Pigeons were exposed to a two‐key concurrent chains schedule in which identical frequencies and distributions of food presentations generated different response rates in the terminal links. An inverse relation between local rate of response in the terminal links and relative frequency of response in the initial links was observed. The high response rate was produced in one terminal link by a second‐order schedule in which responding produced brief blackouts of the response key. Responding under the same schedule in the other terminal link did not produce blackouts. Under initial training and after spatial reversal of the terminal‐link schedules, two of three pigeons had lower relative frequencies of response in the initial member of the chain with the higher terminal link response rate. The third pigeon showed no change in preference at reversal.

Token spending by 20 schizophrenic patients was monitored over a six‐month period. It was found that: (1) token expenditures for cigarettes and “edibles” far surpassed other store item categories; and (2) percentage increases in token expenditures were greatest for categories of items relating to appearance and grooming, strongly suggesting that store purchasing patterns over time may provide an index of program effectiveness.

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Rats pressed a lever to avoid shock on a free‐operant avoidance schedule. Some subjects were also exposed to extinction in which the response‐shock contingency was eliminated while the shock‐shock contingency remained in effect. A specially constructed lever was used that registered not only presses, but also biting attacks on the lever. Throughout various phases of the study, shocks often elicited lever biting as well as post‐shock responding. The results suggested that shock‐elicited attacks that are forceful enough to activate the operandum might account for some of the responding that occurs in experiments on free‐operant avoidance behavior. In particular, shock‐elicited operandum attacking might account for post‐shock response bursting during free‐operant avoidance and the extreme persistence of responding sometimes noted when shocks are delivered during the extinction of avoidance behavior. To the extent that this is true, these phenomena should not be characterized as operant behavior in interpreting the results of experiments on free operant avoidance.