Predictions of two-stage learning theories were evaluated by measuring observing responses which produced the discriminative stimuli for .5 sec. (Editor)

Whether a stimulus compound is separable or integral has predictable consequences for several human information processing tasks. The purpose of these experiments was to explore the implications of this distinction for research in animal learning and the development of learning theory. (Author/RK)

Tests the hypothesis that the effectiveness of discriminative stimuli as reinforcers is a function of the magnitude of the difference between them. (Author/RK)

Several experiments tested the occurrence of the "Kamin effect", i.e., the deficit in performance of an incompletely learned avoidance task, in terms of discrimination (choice) behavior by rats. (Editor/RK)

To complement investigations of the direct effects of lithium toxicosis on consummatory behavior, these experiments were designed to determine the aftereffects on drinking of exposure to a conditioned stimulus previously paired with lithium. (Author/RK)

Three experiments were performed to test the assertion that attractiveness of novel or complex stimuli has confounded experiments on the relative importance of S+ and S- in discrete-trial discrimination. (Editor)

Psychophysical procedures provide the simplest method for studying time discrimination of animals. This experiment examines the psychological threshold of rats in estimating the time of occurrence of an event and how they adjust their behavior accordingly. Further research may determine the theoretical implications for both animals and people.…

Pigeons learned discrimination rapidly and responded differentially to pictures seen for the first time. The essential feature of a natural discrimination--which is the ability to cope with natural ranges of variation--was approached and earlier experimental results were extended using other classes of stimuli. (Author/RK)