We investigated the role of cholinergic neurotransmission in olfactory fear learning. Mice receiving pairings of odor and foot shock displayed fear to the trained odor the following day. Pretraining injections of the nicotinic antagonist mecamylamine had no effect on subsequent freezing, while the muscarinic antagonist scopolamine significantly…

Purpose of the present research was to determine whether certain Pavlovian conditioning phenomena occur in a simple probability learning situation. (Authors)

This paper develops a stimulus selection theory, based on an extensive review of previous research, which gives weight to context change or stimulus generalization decrement. The theory assumes no special compounding or configurational process, and accounts for the learning of successive discriminations without the addition of any special process.…

One hundred twenty-eight preschool boys were subjects in a 4x2x2 factorial design to investigate the change in reinforcer efficacy as a function of prior stimulus exposure. The factors were: (1) amount of repetition, 5, 25, 45, or 65; (2) reinforcer, good or bell; and (3) satiator, good or bell. Two additional groups were run as control groups to…

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)