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Name: Amanda O'Connell
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I was wondering if there are biological or physiological origins to multiple personalities if so what are they?

Well, commissurotomy (surgical splitting of the brain by severing the corpus callosum) appears to result in a person with two distinct behaviors, although neither of these is a complete personality in the usual sense of the word. I don't know offhand of any natural processes that mimic a commissurotomy, but perhaps certain strokes or head injuries do. Oliver Sacks has written a lot of interesting stuff on this subject.

But you may be referring to "multiple-personality schizophrenia," a form of mental illness of enduring popularity in both fiction (from Dr. Jekyll/ Mr. Hyde to James T. Kirk's wolf/lamb) and nonfiction ("Sybil"). The existence of this illness is not universally accepted in the professional mental health community: some workers consider it in the same category as possession by evil spirits. In any event, the origins of schizophrenia are very unclear. A strong basic biochemical influence is suggested by the fact that it tends to run in families and that the most effective means of treatment is not psychotherapy (talking) but certain antipsychotic drugs.

Christopher Grayce

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