A medical simulation The idea that illnesses can be detected, treated, and, in most cases, cured because they have physical causes. This theory was first proposed by Hippocrates in 400 B.C., but it wasn't until the 19th century that scientists began to apply scientific methods to medicine, leading to the development of modern clinical practices. In psychology, the medical model views mental illness as a brain disease, like diabetes or cancer. It assumes that symptoms are caused by abnormalities in the chemical balance or structure of the brain, and treatments should try to restore this balance by using medications or therapies such as electroconvulsive therapy (ECT). The medical model has been widely adopted by psychologists. For example, a large majority of psychologists believe that anxiety disorders are diseases that can be diagnosed based on their physiological effects on the body. Furthermore, antidepressant drugs are viewed as effective only if someone's mental state improves after they are administered. Finally, psychotherapy is usually considered to be an integral part of treatment for most psychiatric conditions. However, there is a growing movement away from the medical model. Some people feel that it gives patients with psychological problems a bad image of themselves.