Editor's Note: With the release of the latest edition of the mental-health manual, the Diagnostic and Statistical Manual of Mental Disorders (the DSM), LiveScience takes a close look at some of the disorders it defines. This series asks the fundamental question: What is normal, and what is not?
Many people would consider a sexual attraction to objects, such as shoes or underwear, abnormal or unnatural. But is it a mental illness? The new edition of the mental-health manual, the DSM-5, offers a conditional answer: It can be, but isn't necessarily.
A fetish may be a multisensory experience as described in both versions of the Diagnostic and Statistical Manual of Mental Disorders. Someone with a fetish may smell, taste, rub or insist that a sexual partner wear the object of their attraction. Often, the fetishist — almost always a man — cannot be aroused without these objects. But the newest edition — the DSM-5 — also classifies intense erotic interest in specific body parts, such as feet or hair, as fetishism.
Fetishism is among a number of unusual attractions, known as paraphilias, that can stray into disorder territory. Unlike the previous version of the manual, the DSM-5 emphasizes the distinction between merely kinky and mentally ill. [Hot Stuff? 10 Unusual Sexual Fixations]
Someone can cross this threshold in a number of ways — for instance, when the attraction causes him significant distress, impairs his ability to function or could lead him to harm others.
The DSM-5 marks this transition by attaching the term "disorder" when an unusual sexual interest crosses these boundaries. So, hypothetically, someone who simply uses shoes to masturbate or whose partner accepts his unusual interest in shoes could be diagnosed with fetishism, but not a fetishistic disorder — unless the fetish crosses the threshold in one of the ways described above.
The label “disorder” is akin to labeling a set of symptoms as a mental illness, which by definition, interferes with normal functioning.
For example, if the fetishist becomes so aroused by his colleagues' footwear that he cannot hold down a job, or if it causes him to steal shoes, he may have a fetishistic disorder, said Robin Rosenberg, a clinical psychologist and co-author of the psychology textbook "Abnormal Psychology" (Worth Publishers, 2009).
A similar line of thought — that a sexual interest or behavior considered abnormal is not, in and of itself, a problem — influenced the removal of homosexuality from the DSM 40 years ago.
The threshold between kinkiness and mental disorder isn’t always straightforward. Sometimes, someone with a fetish may feel uncomfortable because he believes his attraction to objects is abnormal; however, this response to social norms does not mean he necessarily has a disorder, Rosenberg said.
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