Psychologists are the doctors who deals with diseases related to mental illness and disorders, emotional and behaviors disturbances. They are experts in human behavior and have studied the way mind works, and how people think, perceive and behave. Psychologists cannot prescribe medicines and are different from psychiatrists. One may want to visit a psychologist with problems such as depression, anxiety, stress, drug and alcohol abuse, eating disorders, learning disabilities and fears or phobias etc. The use a number of tests and therapies in order to help overcome a patient which includes psychoanalysis, blot ink test etc.