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Five pigeons were exposed to an unsignalled avoidance procedure where key pecks were maintained through shock postponement. Functions obtained showed an inverse relationship between rate of responding and length of the response‐shock interval, while changes in the shock‐shock interval had no systematic effect on response rates. The rate of shocks delivered generally decreased with increases in length of both response‐shock and shock‐shock intervals. Results show that key pecking in pigeons, maintained through an unsignalled avoidance procedure, was affected by changes in response‐shock and shock‐shock intervals in the same manner as other responses in pigeons and in rats.

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Pigeons' key pecking was studied under a number of discrete‐trial fixed‐interval schedules of food reinforcement. Discrete trials were presented by briefly illuminating the keylight repetitively throughout the interreinforcement interval. A response latency counterpart to the fixed‐interval scallop was found, latency showing a gradual, negatively accelerated decrease across the interval. This latency pattern was largely invariant across changes in fixed‐interval length, number of trials per interval, and maximum trial duration. Frequency of responding during early trials in the intervals varied, however, with different schedule parameters, being directly related to fixed‐interval length, inversely related to number of trials, and complexly affected by conjoint variations of fixed‐interval length and number of trials. Response latency thus was found to be simply related to elapsed time during the interval while response frequency was complexly determined by other factors as well.

Chronic, life‐threatening rumination was eliminated in a six‐month‐old infant by squirting a small amount of lemon juice into her mouth whenever rumination or its precursors were detected. A brief suspension of this therapy demonstrated its crucial role. Lemon‐juice therapy offers a practical and acceptable alternative to other therapies for rumination, namely electric shock and massive noncontingent attention. However, since this study is limited to a single case, claims as to the effectiveness of this therapy across children are premature.

Pairing the presentations of one lever (cueing lever) with food led to the acquisition and persistence of lever contacts by rats. This behavior did not occur with a second lever, which was presented randomly with regard to food delivery. This finding obtained whether food delivery was independent of cueing‐lever contacts (positive automaintenance) or dependent on the absence of cueing‐lever contacts (negative automaintenance). The general findings were: (1) cueing‐lever contacts on the positive automaintenance procedure occurred on a higher proportion of trials and at higher rates when contacts occurred than on the negative automaintenance procedure; (2) instances of the cueing lever's failure to support responding were more frequent on the negative than the positive automaintenance procedure; and (3) the topography and median contact duration of positively automaintained responding differed from negatively automaintained responding. These findings agree substantially with the automaintenance literature on pigeons, suggesting that similar processes may characterize automaintained responding in both pigeons and rats.

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Staff performance in a residential child‐treatment facility was measured by counting the number of jobs completed and number of new procedures implemented within one week of their assignment. Public notices were posted listing each staff member's duties and new procedures to be implemented during the week. The notices produced an immediate increase in performance levels, which quickly tapered off. Staff members were then given tokens worth $1.00 each for performing jobs and implementing procedures within one week of assignment. The tokens regained and sustained high levels of performance when used in conjunction with the public notices. The use of public notices alone and tokens alone maintained better performance than baseline levels, but neither was as effective in starting and maintaining high‐performance levels as was the combined use of the two.