In earlier studies with rats, the effectiveness of the auditory element of a tone--light discriminative stimulus was enhanced when the conditioned incentive value of the compound was negative rather than positive. The present experiment systematically replicated these results in pigeons trained to press a treadle in the presence of a tone--light…

Describes the establishment of a psychological space for any set of stimuli by determining metric distances between the stimuli with the probability that a response learned for a stimulus will generalize to the other. (Author/TW)

Projects that soon a complete mechanistic understanding of simple forms of learning will be available. Describes some of the recent advances in neuroscience and psychology in understanding the changes in neural circuits that occur during certain behavioral situations. Suggests that learning involves the activation of second messenger systems. (TW)

Describes recent research findings in the area of neurobiology and its relationship to learning and memory. The article provides definitions of associative and nonassociative learning, identifies essential memory trace circuits of the mammalian brain, and discusses some neural mechanisms of learning. (TW)