According to the composite-stimulus control model (Weiss, 1969, 1972b), an individual discriminative stimulus (S[superscript D]) is composed of that S[superscript D]'s on-state plus the off-states of all other relevant S[superscript D]s. The present experiment investigated the reversibility of composite-stimulus control. Separate groups of rats…

Stimulus overselectivity occurs when only one of potentially many aspects of the environment controls behavior. Adult participants were trained and tested on a trial-and-error discrimination learning task while engaging in a concurrent load task, and overselectivity emerged. When responding to the overselected stimulus was reduced by reinforcing a…

To meet an increasing need to examine the neurophysiological underpinnings of behavior in rats, we developed a behavioral system for studying sensory processing, attention and discrimination learning in rats while recording firing patterns of neurons in one or more brain areas of interest. Because neuronal activity is sensitive to variations in…

STUDIES HAVE SHOWN THAT IT IS POSSIBLE TO ESTABLISH DISCRIMINATORY RESPONSES TO PAIRS OF STIMULI WITHOUT ERROR RESPONSES TO THE UNREINFORCED (S-) STIMULUS. THE PURPOSE OF THIS STUDY WAS TO DETERMINE THE EFFECTS OF 2 METHODS OF INTRODUCING S- (FADING AND CONSTANT) AND 2 RESPONSE CONTINGENCIES (DELAY AND NO DELAY) ON THE OCCURRENCE OF S- RESPONSES.…

Results of 5 experiments supported the hypothesis that many nonlearners in a multipair visual discrimination learning task were following position rather than object strategies and that it was possible to predict individual subjects' strategies from previous performances. (Authors)

This study was designed to examine the effects of age and sex on susceptibility to field dependence training and to determine whether the field dependence phenomenon is a function of cognitive style or of a general inability to make correct judgments because of confusing and inaccurate information. (MS)