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A procedure was developed for use in a public school classroom where only one of the children needed treatment, sophisticated apparatus was not feasible, personnel were untrained in conditioning techniques, and where disruption had to be minimized. Candy reinforcers were contingent upon working behavior. The total candy earned in the session was divided equally among the class. Portable radio control apparatus was adopted to give feedback to the child when he was displaying the desired working behavior. An increase in working behavior and a decrease in talking aloud and out‐of‐seat behavior was observed for each of the four subjects. When the feedback apparatus was removed, the desired behavior was maintained through candy reinforcement alone in all four subjects.

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The pecking response of pigeons is usually measured by a transducer that senses the presence or absence of a response. Typically, the response force as a function of time has not been accurately measured. Data were collected using a transducer specially designed to record the waveform of the pecking response in pigeons. Each response on the target surface of the transducer was reinforced and followed by a blackout. The response was stored on an oscilloscope screen and the peak force and duration of the response were recorded manually from the oscilloscope screen. The mean peak force of the response substantially exceeded the minimum criterion for reinforcement of 35 g (0.343 Newtons) of force. Photographs of the waveform of pecks on the transducer showed great variability in response force and demonstrated that the waveform produced by pecking the target surface was complex. The responses were frequently asymmetrical with the rise time shorter than the fall time, although no single verbal description could be applied to all of the waveforms. Bimodal peaks and double responses were observed and the first peak or response was usually larger than the second. A disadvantage of the transducer was that pecking produced oscillation of the transducer at its resonant frequency. In spite of this deficiency, the waveform of the peck was easily recognizable.

Rats were trained to hold down a lever for at least 40 consecutive seconds. When the lever had been held down for 40 sec, white noise came on. Releasing the bar in the presence of the noise turned off the noise and operated a feeder that delivered a pellet of food. At the end of training, frequency distributions of response durations peaked at 40 to 41 sec. If as in training, holding down the lever produced white noise at the end of 40 sec, and release of the lever terminated the noise and operated the feeder, but no food delivery occurred, duration distributions and several other measures were initially not very different from when food was delivered. However, if during extinction white noise was never produced by lever holding, and feeder operation did not occur upon lever release, most responses were shorter than 1 sec in duration, some were much longer than 41 sec, and duration distributions did not peak at 40 to 41 sec. When reinforcement was reinstated after extinction, performance quickly returned to pre‐extinction measures. Further sessions at different levels of deprivation produced only temporary disruptions in performance.