Author: Lynn P. Rehm, Ph.D.
In 1928 Ivanov-Smolensky, a physician working in Pavlov’s labs, reported on
his observations of a dog that appeared depressed consequent to its inability to
make extremely fine discriminations in a classical conditioning task. The paper
had little impact on the field of depression psychopathology and only in the past
20 years has there been a concerted effort to apply learning models to the
phenomena of depression. During this recent period a number of new theories
have developed. They have led to the generation of a great deal of research data

on the psychopathology of depression and to the development of many new therapeutic approaches to treatment. The theories themselves have been influenced by these developments and revised theories have evolved from earlier forms.