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Pigeons were trained to peck with differing force requirements on a key specially designed to measure and control force of pecking without changes in the mechanical threshold. Following training on a key illuminated by a single wavelength, a generalization test was given. Force and rate gradients were obtained. Force gradients were shown to have a form similar to rate gradients. The slope of the force gradients was a direct function of the force of responding at the conclusion of training. Rate gradients were independent of the force of responding.

A detailed analysis was made of the interresponse times (IRTs) of two rats under both a VI 40‐sec and a VR 15‐sec schedule. Except for the latency of the first response after a reinforcement, the mean IRTs of all further responses differed little. Similarly, the frequency distributions of the successive IRTs did not vary greatly, but were of no simple form. Sequential dependencies between successive IRTs were small, never accounting for more than 1% of the variance.

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Pigeons with one eye covered were trained to discriminate intensities or colors of stimuli located to one side of the head, or intensities, colors or forms of stimuli located in front of the beak. Each discrimination transferred to the covered eye, even when previous training with the covered eye included the reversal of the tested discrimination. Pigeons also were able to learn conditional discriminations in which appropriate responding depended on which eye was covered.

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This study concerns the use of a multiple stimulus discrimination procedure for producing data on the generalization of conditioned suppression. Four rats were maintained on a variable interval schedule of milk reinforcement in the presence of five stimuli varying in auditory click rate. When response rates were stable, electric shock was regularly paired with the termination of one of the click stimuli. For two rats the shock was paired with the slowest click rate, and for two rats shock was paired with the fastest click rate. The VI schedule remained in effect. Plots of the relative rates of response to each of the five stimuli yielded concave gradients for both animals suppressed at the slowest click rate, and flat gradients with a sharp drop at the warning stimulus for both animals suppressed at the fastest click rate. When the warning stimuli were reversed for both pairs of subjects, both gradient forms were reproduced. The present procedure was contrasted with procedures used by other investigators.

The effects on monitoring performance of a limited hold (LH) terminated by a bell or by electric shock and of periodic rest periods were investigated. The sensitivity of basal skin conductance to different monitoring conditions was also studied. Humans monitored a visual display in several 2‐hr sessions under the Holland procedure. In each session, signals were programmed by one of the following three multiple schedules: a variable interval of 6 min (VI 6) and a VI 6 with a limited hold (LH) terminated by a bell; a VI 6 and a VI 6 LH terminated by electric shock; a VI 6 LH terminated by shock and a time‐out (TO). The two components of each schedule alternated at 15‐min intervals. The average observing response rate of eight subjects was lowest during the VI 6 periods, higher in periods when the LH was terminated by a bell, and highest when the LH was terminated by shock. Periodic TO periods did not appreciably increase the response rate under the VI 6 LH shock component. A differential level of palmar skin conductance under the two components of a schedule was present only under the mult VI 6 LH shock‐TO.

Punishment and escape were studied simultaneously by allowing a subject to escape from a stimulus situation in which responses were punished, into a stimulus situation in which responses were not punished. The frequency of the punished responses was found to be an inverse function of the intensity of punishment, whereas the frequency of the escape response was a direct function of the intensity of punishment. Both of these functions were obtained under three different schedules of food reinforcement. The strength of the escape behavior was evidenced by (1) the emergence of the escape response even when the frequency of food reinforcement decreased as a consequence of the escape response, (2) the maintenance of the escape response by fixed‐interval and fixed‐ratio schedules of escape reinforcement, and (3) the occurrence of escape responses at intensities of punishment that otherwise produced only mild suppression of the punished response when no escape was possible. This last finding indicates that a subject may be driven out of a situation involving punishment even though the punishment is relatively ineffective in suppressing the punished responses when no escape is possible.