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This study investigated a teacher‐implemented prompting procedure for training students to ask questions. Two special‐class (EMR) students who asked no questions were selected as subjects. Baseline data were also collected on reading comprehension and on‐task behavior, and these suggested decreasing levels of performance. The results indicated that prompting was effective for initiating question‐asking. In addition, increased levels of reading comprehension and on‐task behavior were observed.

The autoshaping procedure confounds the effects of pairing a keylight and food with the effect of adventitious food reinforcement of responses that typically occur before the pecking response. In Experiment I, acquisition of the orientation to the key, the approach toward the key, and the peck at the key were systematically monitored. Orientations to the key and approaches toward the key frequently occurred in contiguity with food presentation before peck acquisition. In Experiment II, a negative contingency procedure was used to assess the sensitivity of the approach toward the key to its consequences. When the approach toward the key resulted in nonreinforcement, the probability of occurrence of that response decreased to zero despite repeated light‐food pairings. In Experiment III, peck probability was shown to be determined during the approach toward the key by the presence of stimuli that had previously been either paired or nonpaired with food. In Experiment IV, it was shown that the effects of the stimulus present during the approach toward the key were not due solely to the effects of pairing that stimulus with food. Autoshaped key pecking appears to be determined by the interacting effects of stimulus‐reinforcer and response‐reinforcer variables upon orientations to, approaches toward, and pecks at the lighted key.

The study investigated the effect of total darkness on the key pecking of pigeons under fixed‐ratio, variable‐ratio, fixed‐interval, and variable‐interval schedules of food reinforcement. Eight pigeons were divided into groups of two, with each group conditioned to peck under one of the four schedules of reinforcement. Under an ABAB procedure, all pigeons experienced alternating light and dark conditions. The house‐ and keylights were (a) maintained at full intensity for the first 30 one‐hour sessions, (b) faded out and disconnected over Sessions 31 through 50, (c) totally illuminated for Sessions 51 to 60, and (d) disconnected again for the final 10 sessions. Responding under the ratio schedules increased from 20% to 108% in the dark and responding under the interval schedules in the dark decreased by 37% to 93%.

Calibration of a standard pigeon box subsequently modified for use as an acoustical chamber in a frequency discrimination experiment revealed that the enclosure was not acoustically “flat”. Standing waves were detected at each of the six frequencies measured. To ascertain whether the maximum standing waves recorded (3.0 dB) could serve as an added or alternative cue for pigeons tested in the chamber on a frequency discrimination problem, pure‐tone intensity difference thresholds were determined for two pigeons at 1.0, 2.0, and 3.0 KHz. The results of the experiment indicated that the smallest intensity difference detectable was 10.0 dB, a value that was 7.0 dB above the maximum standing wave measured in the box. These data suggest that the modified pigeon chamber is suitable to test pure‐tone frequency discriminations in pigeons in the range of 1.0 to 3.0 KHz.

Two experiments were conducted to investigate the quantitative relationship between response rate and reinforcement frequency in single and multiple variable‐interval avoidance schedules. Responses cancelled delivery of shocks that were scheduled by variable‐interval schedules. When shock‐frequency reduction was taken as the measure of reinforcement, the relationship between response rate and reinforcement frequency on single variable‐interval avoidance schedules was accurately described by Herrnstein's (1970) equation for responding on single variable‐interval schedules of positive reinforcement. On multiple variable‐interval avoidance schedules with brief components, asymptotic relative response rate matched relative shock‐frequency reduction. The results suggest that many interactions between response rates and shock‐frequency reduction in avoidance can be understood within the framework of the generalized matching relation, as applied by Herrnstein (1970) to positive reinforcement.

This study investigated the relationship between a teacher's contact durations and the off‐task behavior of students not in contact with the teacher. Contact durations were defined as the amount of time the teacher spent working individually with each student. Off‐task behavior was recorded for six third‐graders who comprised a small instructional group in mathematics. After baseline established that contact durations averaged approximately 38 sec, the teacher was instructed to hold contacts for at least 50 sec. During this phase, the students' off‐task behavior increased. The teacher was then instructed to hold contacts for only 20 sec. During this phase, the students' off‐task behavior decreased.

Three albino rats were given extensive exposure to an escape procedure in which shocks were scheduled to occur 30 sec apart. The amount of downward force exerted on the lever was continuously recorded and compared with traditional discrete measurement in which only responses above an arbitrary force threshold were recorded. Subjects typically remained in contact with the lever throughout the shock‐free intertrial interval. Shock onset reliably occasioned a brief lurch from and return to the lever, which resulted in a lever‐press escape response being recorded. Lever contact, which occupied an average of 90% of session time, showed great stability in force after a brief (e.g., 5‐sec) period of instability after each shock terminated. In general, continuous measurement revealed considerably different results than discrete measurements of on‐lever behavior. For example, continuous lever contact fluctuating near response threshold was often recorded as discrete responding, and sustained lever contact occurring below response threshold was omitted from discrete measurement.

A fifteen‐year‐old severely disturbed girl was treated for aphonia. Because of the extent of her withdrawal, the subject was conditioned in a laboratory setting and received tokens for speaking loudly enough to operate a voice‐operated relay. Conditioning at first consisted of saying 100 monosyllabic words, with the possibility of reinforcement on each word. Later, the subject was required to say a polysyllabic word, and finally, five or six words per token. The subject was shaped to speak with normal loudness in the laboratory, and generalization to a reading situation in the laboratory was measured and observed to occur, at first for a few minutes, and later for a longer period. Generalization to a reading situation in the classroom did not occur, but the subject's voice loudness also increased in the classroom when several new reinforcement contingencies were put into effect there.

Pigeons were trained under an observing response procedure in which pecks on one key (food key) were reinforced under a mixed fixed‐interval 30‐sec extinction schedule. A response on a second (observing) key replaced the mixed‐schedule stimulus with either of two multiple‐schedule stimuli (red and green keylights) for 5 sec. Observing response rates were positively correlated with food‐key response rates in the presence of multiple‐schedule stimuli and inversely related to food‐key response rates in the presence of mixed‐schedule stimuli. These results suggest that observing response output is controlled not only by the stimuli produced by observing responses but also by the stimuli in the presence of which observing responses occur. The possibility that observing responses alter the probability of reinforcement is advanced.

Four groups of four pigeons each were studied on two different multiple schedules. The cues correlated with the schedule components were localized on the response key for two groups and were not localized for the others. Two groups worked on multiple schedules with variable interval 15‐sec in both components, and variable interval 15‐sec in one component and extinction in the other. The other two groups had identical procedures except that food was presented on a response‐independent variable‐time schedule. Variable‐interval birds with localized stimuli showed marked behavioral contrast; variable‐interval birds with non‐localized stimuli showed no behavioral contrast. Variable‐time birds with keylight stimuli acquired high rates of autopecking, which changed as treatment changed in a manner that paralleled rate changes, resulting in behavioral contrast for variable‐interval birds. Variable‐time birds with non‐localized stimuli key pecked only at a low rate. The findings indicate that behavioral contrast in pigeons may result from the autopecking that is obtained with stimulus‐contingent food presentation.