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The effects of presenting a different (“eccentric”) stimulus for one interval during either or both components of a cyclic multiple fixed‐interval fixed‐interval schedule, with 12 short and four long intervals per cycle, were studied in three experiments. Eccentric stimuli in the short‐interval component reliably produced a persistent, substantial elevation in key‐peck rate. The effect appears to depend on schedule context and an initial “disinhibiting” effect of the eccentric stimulus.

Pigeons were studied in a two‐component multiple schedule. In the first phase of the experiment, key pecks were reinforced on a variable‐interval 2‐min schedule in both components and free food was delivered additionally during one component. When components alternated every 8 sec, all pigeons pecked at a much higher rate during the component with free food than during the other component. At a component duration of 16 min, the reverse was true: all pigeons pecked at a higher rate during the component without free food. In the second phase, the additional food during one component was made contingent on pecking. Responding during the component without the extra food remained essentially unchanged, as expected, since rate of reinforcement remained identical to that in the previous phase. However, rate of responding during the component with the extra food (now contingent on pecking) was elevated, compared to the rate in the first phase, and did not show the marked decline as component duration was increased.

The effects of automated cueing on teacher praise rate was investigated in one special, one fourth‐, and one seventh‐grade classroom. After establishing baseline praise rates in each of the three classrooms, two methods for increasing teacher praise rate were introduced according to a multiple‐baseline design. During the first phase, two teachers were instructed to count and graph their praise rate during each session. All teachers received auditory cues to prompt praising during another phase. In all cases, introduction of cues markedly increased teacher praise rates, but self‐recording was relatively ineffective. An analysis of teacher‐praise distributions showed that cues closely controlled teacher praise for two of the three teachers.

After systematic attempts to increase a teacher's positive responding to her first‐grade students, a token‐economy system was implemented as a “last resort”. On‐task student behavior and relative frequency of positive and negative teacher comments were systematically observed. Data indicated that institution of the token system was associated with a relatively higher percentage of positive than negative comments. Termination and re‐implementation of the token system caused reversals of the teacher's behavior.

This study investigated shock‐induced aggression as a function of housing rats in single or communal cages for varying periods of time before testing. Rates of fighting were unaffected by housing conditions when rats spent seven or 14 days in either of these settings before testing. Placing rats in these settings for 21 or 28 days before testing, however, did affect rates of fighting. Communal caging of subjects for 28 days before testing was particularly deleterious to shock‐induced aggression. How rats are housed outside the experimental chamber is a variable affecting shock‐induced aggression and should be considered both in designing future studies and as a topic for future investigation.

Two different prompting procedures to teach visual and auditory discriminations to autistic children were compared. The first involved presenting an added cue as an extra‐stimulus prompt. This required the child to respond to both prompt and training stimulus. The second involved the use of a within‐stimulus prompt. This consisted of an exaggeration of the relevant component of the training stimulus and thus did not require that the child respond to multiple cues. The results indicated that (1) children usually failed to learn the discriminations without a prompt, (2) children always failed to learn when the extra‐stimulus prompt was employed but usually did learn with the withinstimulus prompt, and (3) these findings were independent of which modality (auditory or visual) was required for the discrimination.

Effects of d‐amphetamine, chlorpromazine, and chlordiazepoxide on lever pressing under direct control of spaced‐responding schedules were compared with effects on intercurrent drinking and wheel running in the rat. Drug effects on lever pressing were systematically related to dose and were consistent for all animals; drug effects on intercurrent behavior were generally different for each animal. In the case of lever presses, increasing doses of d‐amphetamine first increased and then decreased response rate, increasing doses of chlorpromazine produced graded decreases in response rate, and doses of chlordiazepoxide up to 40 mg/kg produced no effect on response rate. These data are discussed in context with the concept of schedule control, and it is suggested that the behavioral pharmacology of intercurrent behavior be explored as a useful procedure in the experimental analysis of intercurrent behavior.

Pigeons were trained in three conditions. In the baseline condition, the birds responded on a fixed‐interval schedule with the response key white. When the interval was completed, the key turned either red or green for a delay interval that was terminated by a grain presentation dependent on no key pecks during the final 2 sec. In the uncertainty condition, no grain was presented at the end of the delay periods when the key was red. In the certainty condition, the white light appeared only on occasions when pecking would turn the key green and produce food. Otherwise, the key was illuminated red throughout the total time period. The highest response rate in white occurred in the uncertainty condition, the next highest in the certainty condition, and the lowest in baseline. The results suggest that uncertainty facilitated responding, although uncertainty is not a necessary condition for conditioned reinforcement.

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