Medical Disorder View of Abnormality

brainIf an underlying physical condition affects behaviour, the behaviour is considered to be abnormal and not just a symptom of the physical disorder. Included in this definition are Alzheimer's disease, Down syndrome, and many other conditions.

Psychologists holding this view hoped that biological causes could be identified for all psychological problems; they now know this is not possible. For example, conversion hysteria (symptoms may include becoming blind and/or deaf with no physical cause), is the result of an unconscious and ineffective coping mechanism used to deal with unwanted emotions. Individuals with multiple personality disorder (MPD), also known as dissociative identity disorder, can also be included here. One case study, described in an 1840 monograph by Despine (and recounted by F. Putnam) involved an 11 year-old girl, Estelle, who initially exhibited paralysis and hypersensitivity to touch. Estelle later developed a second personality who could walk and play but could not tolerate her mother's presence. She exhibited marked differences in behaviour, preferences, and relationships between the two personality states. The power of the mind is astounding!