How is a Psychologist different from a Psychiatrist?

These two professions differ in terms of historical development, educational history, primary theoretical orientation for assessment and treatment, and (in Ontario) support under government insurance.

Psychology arose as the science of mind and behaviour, whereas psychiatry arose within the context of mental diseases or disorders. A psychologist is normally a Ph.D. in behavioural science (psychology), whose principal emphasis is on human adaptation and learning, and who is not funded by OHIP.

A psychiatrist is a M.D. in medicine with a specialization in psychiatry, who principal emphasis in a ‘medical’ model of mental health where medications is the preferred treatment, and whose services are covered by OHIP. There are many exceptions to these generalizations.

What is a Mental Disorder?

Most generally, a mental disorder is a disturbance in functioning caused by problems with some psychological factors – behavioural, cognitive, or emotional. At one end, mental disorders can have purely physical, biochemical causes, and at the other, purely learned or psychological causes. The former kind of cause encourages understanding mental disorder as mental illness, whereas the latter kind of cause encourages understanding mental disorders as dysfunctions.