Early Research on Classical Conditioning Was Performed with Dogs

Short Answer

Early research on classical conditioning was performed with dogs. In certain variations of this research, experimenters repeatedly presented dogs with meat powder just after ringing a bell. The dogs (who would naturally salivate after being exposed to meat powder)learned to associate the bell with the meat powder, and began to salivate as soon as they heard the bell. In the language of classical conditioning, the meat powder in this research served as a(n)________________.