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Pigeons' choice responses on either of two keys occasionally produced entry into a terminal link associated with that key. During the terminal links, responses produced access to grain according to mixed‐ or multiple‐interval schedules. The multiple schedules provided stimuli correlated with the interval of time preceding reinforcement whereas the mixed schedules did not. The two subjects reliably preferred the multiple schedules to the mixed schedules throughout a series of replications. Preference for the multiple schedule was much smaller than suggested by earlier work comparing multiple and mixed schedules that had much higher rates of entry into the terminal links. Preference for the multiple schedule was greatly increased in this study when the rate of entry into the terminal schedules was increased. As in previous studies, these high preferences may have been the result of a sharp increase in the number of reinforcements on the multiple (as opposed to the mixed) schedule. The reliable but smaller preferences for the multiple schedule found with lower rates of entry into the terminal links were unconfounded by differences in the number of reinforcements obtained in the two terminal links.

The social interaction between a behaviorally disordered preschool child and her classroom peers was measured under two conditions of contingent adult attention: (1) verbal praise and physical contact directed to the target subject's peers for appropriate interaction with the target subject, and (2) verbal praise and physical contact directed specifically to the target subject for engaging in appropriate interaction with peers. Continuous measures of interactive behavior were made during baseline, intervention, and return to baseline conditions. Results indicated that application of experimental contingencies to peers (Condition 1) rapidly increased appropriate social behaviors by the peers and also by the target subject. When experimental contingencies were applied to the target subject (Condition 2), a similar increase in appropriate social behaviors was noted for both the target subject and the peers. Additionally, during Conditions 1 and 2 the recipient(s) of contingent adult attention initiated more appropriate social contacts than did the interacting partner(s).

The relationship between student behavior change and teacher reactions to the change was investigated. One fifth‐grade teacher served as the subject and two students in her class were employed as teacher change agents. In a multiple baseline design, the students' disruptive behavior (the independent variable) was modified without the teacher's knowledge. The teacher's reactions toward the students (the dependent variable) was monitored on several dimensions including: teacher behavior, teacher attitude toward students, and the quality of teacher verbal statements. Results indicated that student behavior change influenced the teacher's behavior. Implications are that students possess potent reinforcing properties for teachers and that students should be trained to be effective students.

Pairs of rats received grid shock in a conical enclosure. Each shock elicited the stereotyped fighting posture. An omnidirectional pole, which was always between the rats, was accidentally operated whenever the rats fought. The number of pole hits, and the number of observed fight bouts, increased with current intensity. The number of pole hits served as a reliable and objective measure of shock‐induced fighting in rats.

In urban high‐density areas, litter has become an increasingly obvious and pervasive problem. In the present study, repeated measures of the amount of litter on randomly selected yards in an urban low‐income housing project were used to evaluate the effectiveness of a series of anti‐litter procedures directed at the children residing in the project. Paying children for volume of trash collected resulted in only a small decrease in the number of litter pieces present. Paying them for cleaning assigned yards markedly decreased the level of litter in all sampled yards. Thus, children can be employed to maintain a clean neighborhood in spite of the rapid accumulation of new litter in urban yards.

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Two 4‐yr‐old hearing‐impaired girls were trained to articulate correctly /f/ and /sh/ phonemes in the initial position of words in response to pictures. They were first trained to imitate, and then to respond on demand of “what's this?” As a result, both girls generalized correct articulation to words requiring both phonemes in the initial and final positions.

A bottlenose dolphin, already highly proficient in two‐choice auditory discriminations, was trained over a nine‐day period on auditory delayed matching‐to‐sample and then tested on 346 unique matching problems, as a function of the delay between the sample and test sounds. Each problem used new sounds and was from five to 10 trials long, with the same sound used as the sample for all trials of a problem. At each trial, the sample was projected underwater for 2.5 sec, followed by a delay and then by a sequence of two 2.5‐sec duration test sounds. One of the test sounds matched the sample and was randomly first or second in the sequence, and randomly appeared at either a left or right speaker. Responses to the locus of the matching test sound were reinforced. Over nine, varying‐sized blocks of problems, the longest delay of a set of delays in a block was progressively increased from 15 sec initially to a final value of 120 sec. There was a progressive increase across the early blocks in the percentage of correct Trial 1 responses. A ceiling‐level of 100% correct responses was then attained over the final six blocks, during which there were 169 successive Trial 1 responses bracketed by two Trial 1 errors (at 24‐ and 120‐sec delays). Performance on trials beyond the first followed a similar trend. Finally, when the sample duration was decreased to 0.2 sec or less, matching performance on Trial 1 of new problems dropped to chance levels.

Following exposure for a minimum of 500 to 600 trials, three of four naive squirrel monkeys eventually pressed a response key, illumination of which always preceded delivery of a food pellet. Three other naive monkeys did not press the key when the pellets were delivered randomly with respect to key illumination. Despite some similarities to autoshaping using pigeons, the data indicate many points of difference when squirrel monkeys are used as subjects. Although key‐food pairings were shown to be important in the acquisition of the key‐press response, they were ineffective in maintaining the response when either a negative response‐reinforcer dependency was introduced, or when there was no scheduled response‐reinforcer dependency (fixed trial). Not all demonstrations of autoshaping can be considered to be under the control of those processes that are primarily responsible for the phenomena obtained in pigeons.

The key pecking of pigeons was autoshaped to three key colors paired with food in discrete trials. Then, the effects of three different color‐correlated contingencies were compared: reward (presentation of food contingent on pecking), omission (presentation of food prevented by pecking), and extinction (no food). Two measures of performance were used: initial response (the number of trials with each color on which at least one peck was made) and multiple response (the total number of pecks per trial). In general, the reward color produced more pecking than the omission color, the omission color more than the extinction color, and the extinction color more than on blank trials with an unlighted key, although (relative to reward) omission produced a higher level of initial than of multiple responding. These results point clearly to the importance of stimulus‐reinforcer continguity in the control of pecking.