Psychiatrists are medical doctors who have completed their residency training in the physical and neurological foundations of emotional and mental disorders.  Psychiatrists follow a medical or biological model of treatment:  mental disorders result from physical and/or neurological dysfunction, and therefore should be treated medically.  Their level of education and training provides psychiatrists with an in-depth knowledge of the benefits and limitations of specific types of medications in treating specific types of mental illness, allowing them to prescribe medication as a treatment modality. 

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Psychologists have earned doctoral degrees in philosophy (Ph.D.) or psychology (Psy.D.).  Clinical psychologists have the most rigorous training in theories and techniques of psychotherapy, and can administer and report the results of psychological testing.  Psychologists focus on the psycho-therapeutic mode of treatment: working together with their patients to identify and resolve the negative thought and behavior patterns that are disrupting their quality of life through cognitive and behavioral intervention.

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