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Three groups of pigeons were given conditional discrimination training in which the number of standard stimuli was varied across groups. In the presence of each standard, a pigeon adjusted the comparison stimulus on a second key until the two keys matched. A report of this match (response on the first key) was reinforced. Transfer of the matching performance was investigated by adding new standards to the ones already available. All pigeons were exposed to two extinction sessions after 155 sessions of training. Rapidity of acquisition was inversely related to the number of standards presented. Generalization gradients derived from the several comparison stimuli showed that all pigeons reached a high level of accuracy in the presence of at least one standard, and some pigeons did so in the presence of as many as four of the six standards. There was no evidence of a systematic effect of extinction upon overall accuracy, or the individual generalization gradients. When a new standard was added, a given pigeon's performance (in terms of responding to the comparisons) was similar to performance in the presence of one of the old standards. However, the pigeons did not show evidence of confusion among the comparisons.

Pigeons' pecks at one or two wavelengths were reinforced intermittently. Random series of adjacent wavelengths appeared without reinforcement. Gradients of responding around the reinforced wavelengths were allowed to stabilize over a number of sessions. The single (one reinforced stimulus) and summation (two reinforced stimuli) gradients were consistent with a statistical decision account of the generalization process.

Neurological patients were subjects in delayed visual matching‐to‐sample. The sample and choice stimuli were ellipses of varying size. By measuring the difference in size between the sample on a given trial and the ellipse the subject chose on that trial, gradients of differences between samples and choice stimuli could be plotted. These difference gradients broadened with increasing delays. Sharp gradients were controlled by the samples. Flat gradients were controlled by features of the choice display, independently of the samples. Intermediate gradients reflected combined control by the samples and by the choice displays.

In a modified conditioned suppression procedure, clicks at one frequency (danger signal) preceded shocks, while no shocks followed clicks at a different frequency (safe signal). During generalization tests, the maximal response rate was frequently shifted from the safe signal in the direction away from the danger signal, and the minimal response rate was frequently shifted in the opposite direction, away from the safe signal. There was considerable variability in the results from one animal to another. The generalization tests also suggested different generalization functions according to whether the danger signal was a lower or a higher frequency than the safe signal. The results also showed the development of systematic differences in response rate during and after the safe and danger signals, notably a relatively high rate at the beginning of the safe signal and after the danger signal.

Out‐of‐seat and talking‐out behaviors were studied in a regular fourth‐grade class that included several “problem children”. After baseline rates of the inappropriate behaviors were obtained, the class was divided into two teams “to play a game”. Each out‐of‐seat and talking‐out response by an individual child resulted in a mark being placed on the chalkboard, which meant a possible loss of privileges by all members of the student's team. In this manner a contingency was arranged for the inappropriate behavior of each child while the consequence (possible loss of privileges) of the child's behavior was shared by all members of this team as a group. The privileges were events which are available in almost every classroom, such as extra recess, first to line up for lunch, time for special projects, stars and name tags, as well as winning the game. The individual contingencies for the group consequences were successfully applied first during math period and then during reading period. The experimental analysis involved elements of both reversal and multiple baseline designs.

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An attempt was made to increase the frequency with which chronic schizophrenic patients suggested feasible improvements in their treatment. A response priming procedure was devised that was comparable to a previously developed reinforcer exposure procedure. The patients were required to attend a structured meeting during which they were prompted to make suggestions. This priming procedure was compared with the more usual procedure of “welcoming” attendance and suggestions. It was found that more suggestions were made when attendance was required, rather than optional. This increase occurred during a group as well as a private meeting. An attempt was then made to analyze the probable reinforcer for the suggestions by experimentally varying the percentage of suggestions followed. Different staff members served as the discriminative stimuli within a multiple schedule. It was found that the number of suggestions was a direct function of the percentage followed. These results demonstrate the effectiveness of the priming procedure as an adjunct to reinforcement procedures for increasing desired behaviors of mental patients. Few suggestions were made when reinforcement or priming were used alone.

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Four of seven human male subjects developed full penile erections when exposed to erotically stimulating motion pictures. Changes in penile size were detected by a mercury strain gauge transducer and automatically recorded on a continuous paper record. When instructed to inhibit penile erection in the presence of such effective stimulus films, every subject was able to reduce his erection by at least 50%. This inhibition was apparent as long as the instructions were in effect; when the instructions were removed and the film reshown, the erection returned almost to its maximum state. This was true whether the films were presented as few as three or as many as nine times in succession. When instructed to develop an erection in the absence of a film, every subject was able to do so, each reaching a peak of about 30% of his maximum. Such erections had longer latencies to the peak produced and lower maximum levels than those elicited by a film.

To determine the effects of variable‐interval shock punishment on behavior maintained by variable‐interval and variable‐ratio reinforcement, human subjects' key‐pressing behavior was reinforced with money on a four‐component multiple schedule. Components 1 and 2 were variable‐interval 30‐sec, and Components 3 and 4 were variable‐ratio 210. After responding was stabilized, response‐contingent electric shock was scheduled on a variable‐interval 10‐sec schedule during the second and fourth components of each cycle. Subjects instructed as to the reinforcement contingencies showed gradually increasing suppression of variable‐interval responding at increasing shock intensities and either very high or very low rates of variable‐ratio responding at higher intensities. Minimally instructed subjects showed suppression at higher shock intensities, but no clear differential suppression as a function of reinforcement schedule. Recovery from initial suppression was observed within sessions.