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Rates and patterns of responding of pigeons under response‐independent and response‐dependent schedules of brief‐stimulus presentation were compared by superimposing 3‐min brief‐stimulus schedules on a 15‐min fixed‐interval schedule of food presentation. The brief‐stimulus schedules were fixed time, fixed interval, variable time, and variable interval. When the brief stimulus was paired with food presentation, its effects depended upon the schedule and ongoing rates. Fixed‐ and variable‐interval brief‐stimulus schedules enhanced the low rates normally occurring early in the 15‐min interval, whereas fixed‐ and variable‐time schedules suppressed these rates. Although the overall rates later in the interval were not affected to any great extent, the fixed brief‐stimulus schedules generated patterns of positively accelerated responding between stimulus presentations. These patterns appeared less frequently under the variable brief‐stimulus schedules. Initially, when not paired with food delivery, presentations of the brief stimulus produced relatively little effect on either response rate or patterning. However, once the stimulus had accompanied food presentation, the original performance under the non‐paired condition was not recovered. The effects were more like those occurring when the stimulus was paired with food.

Three pigeons pecked for food in two experiments in which each trial consisted of two phases: a study and a test phase. The study phase in Experiment i consisted of two stimulus‐response pairs presented successively. Each pair consisted of the illumination of a left or right key (the stimulus) and a peck on the lighted side key (the response). The study phase in Experiment ii consisted of three such pairs presented successively. a retention interval, varied between 0.1 and 4.0 sec, separated the study phase from the test phase. The test phase of a trial began with the illumination of the center key by one of two (Experiment i) or three (Experiment ii) colors. This color was the same as the stimulus element of one of the pairs in the study phase. a reinforcer was presented if a subject then emitted the response element of the indicated stimulus‐response pair. The results provide information on the conditions that enable a pigeon to remember the responses most recently emitted in the presence of various stimuli. The results suggest an account of the maintenance of behavior that is temporally noncontiguous with reinforcement.

Analytic methods of signal detection theory were employed to assess the utility of reinforcers. Four pigeons were trained to detect the presence or absence of a stimulus by pecking one of two side keys in a trial‐by‐trial choice paradigm. The relative rate of positive reinforcement for correct choices was varied to offset the biasing effects of electric shock for incorrect right side‐key choices. The effects of relative rate of reinforcement on bias were similar at all shock intensities even though the subjects' sensitivity changed during the course of the experiment. The relative rate of reinforcement required to produce equal bias was calculated and plotted against shock intensity to generate utility functions. The relative rate of reinforcement necessary to offset the bias induced by shock was an increasing function of shock intensity.

At several fixed and variable minimum reinforced interresponse times, a stimulus was added to differential‐reinforcement‐of‐low‐rate schedules to signal the availability or nonavailability of reinforcement. As the minimum reinforced interresponse time increased, the rate of unreinforced responding decreased. Changing from fixed to variable minimum interresponse time in the basic differential‐reinforcement‐of‐low‐rate schedule further decreased the rate of unreinforced responding. Both effects were to some degree reversible. For fixed minimum reinforced interresponse times of 30 sec or shorter, most unreinforced responses terminated interresponse times just short of that required for reinforcement. The minimum reinforced interresponse time and the number of short response latencies (≤0.5 sec) to the onset of the signal were negatively correlated. Both of these analyses suggested that at values of 30 sec or shorter, the subjects discriminated the availability of the reinforcer more on the basis of time than on the basis of presence or absence of the signal.

Children in a first‐grade classroom were divided into four groups. Baseline measures of disruptive classroom behavior were taken on a well‐behaved and disruptive child in each group. Following baseline, four types of token economies were simultaneously introduced and rotated every 10 days within a Latin Square design. The token economies were: (1) individual reinforcement determined by individual performance; (2) group reinforcement determined by the behavior of the most disruptive child; (3) group reinforcement determined by the behavior of the least disruptive child; (4) group reinforcement determined by the behavior of a randomly chosen child. The token economies were compared on their effectiveness in changing target behavior, preference by the targets, ease of use, and cost. Additionally, sociometric responses were taken on questions of responsibility, friendship, and funniness. Results showed a significant decrease of inappropriate behavior for the disruptive children and no difference between the effectiveness of the four types of token economies in producing behavior change. However, there were other differences that indicated that the system in which group reinforcement was determined by a randomly selected child would be desirable for most teachers. Results also showed changes in the sociometric status of the disruptive children. As predicted, disruptive children were rated as more responsible when they were in the group reinforcement determined by the most disruptive child in the group token economy. Using behavior modification techniques indirectly to change sociometric status is suggested as offering a new potential technique for behavior change agents.

Head poking, a suggested natural escape reaction to shock for the rat, was compared to lever pressing in a Sidman avoidance study. Both responses could be emitted at any time, but only one was effective in a given session. Acquisition and extinction of the two responses were compared under both signalled and unsignalled avoidance. Then, a test for transfer was conducted in which acquisition conditions were re‐instated, but the effectiveness of the responses was reversed. Three differences between responses were noted: (a) head poking was superior in reducing shock rates under signalled conditions; (b) head poking was more resistant to extinction, especially under signalled conditions; (c) under unsignalled conditions, animals were unable to learn to head poke if they had previously learned to lever press. Findings a and c were pursued in later experiments. Finding a depended on the location of the warning signal with respect to the response system. When the lever press required approach to the warning signal, the head poke was superior. But when the head poke required approach to the warning signal, the two responses were equally effective. Finding c depended on the absence of feedback for head poke during transfer. Two conclusions are offered: first, the two responses appear to obey the same laws when their topographical differences are taken into account. Second, response feedback appears to be more critical in transfer than in original acquisition.

Descriptive and inferential statistics are described as judgemental aids, stimuli to which the scientist can more easily react than to his raw experimental results. The increasing emphasis on the significance test as the main judgemental aid utilized in experimental psychology is credited with several harmful effects on experimental practice. The area known as “the experimental analysis of behavior” has so far escaped most of these harmful effects, but now we see an increased interest in the development of appropriate significance tests for individual organism research. This interest is based on the view that it is not possible to effect adequate levels of experimental control with much human applied research, and that in such cases a significance test would be quite valuable as a judgemental aid, both of which points are considered to be essentially incorrect, and if accepted, potentially harmful.

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A new method was used to investigate auditory discrimination in pigeons. Basically, the method involves the repeated presentation of one stimulus preceding the single presentation of a different stimulus that is followed by shock. Stimulus control is assessed by the increase in heart rate that accompanies the presentation of the second stimulus. In Experiment 1, the efficiency of the method was explored by determining the frequency difference thresholds of pigeons at 500, 1000, 2000, and 4000 Hz. Weber fractions comparable to those reported in an earlier study using the conditioned suppression method were obtained. Experiment 2 demonstrated that, contrary to results of earlier studies, auditory temporal patterns can exercise differential stimulus control in pigeons. One stimulus consisted of the presentation (once per second) of a 1000‐Hz pure tone of 150 msec duration followed by a 2000‐Hz pure tone of equal duration; the other was the same except for the reversed order of the frequency components. Results indicated that the frequency pattern and not the loudness pattern of the stimuli was the cue controlling heart‐rate changes.