French politician and International Monetary Fund chief Dominique Strauss-Kahn, arrested in New York Saturday for attempted rape, has long trailed a reputation among France's cognoscenti as an ardent womanizer.
But when does an outsized appetite for sex morph into something deviant or violent? When does serial seduction give way to sex addiction?
"These concepts must be treated with caution, because we are at the border between so-called normal and pathological behaviour," said psychiatrist Jean-Claude Matysiak, head of the addiction unit at Villeneuve Saint-Georges hospital outside of Paris.
For William Lowenstein, director of the Montevideo Clinic near Paris, it is nonetheless possible -- and important -- to distinguish between seduction, obsession and addiction.
Seduction, he said, is "conquering the desire of another person", and is rarely coupled with acts of aggression.
Obsession typically shows up in the context of a crisis, triggered by an incident or a trauma. "At that point, all the psychic tension focuses on the sex organs," he explained in an interview.
Sex addiction, however, is characterised by a loss of rational control, as well as significant and measurable changes in the neurochemistry of the brain.
"Willful rationality is no longer the orchestra conductor -- knowing that something is bad for your health, or your social or professional life, is not enough to modify addictive behaviour," Lowenstein said.
"There is a loss of control," agrees Matysiak, adding that even when patients recognise they have a problem, they are unable to reign it in.
This can lead to "acts of aggression in order to satisfy these impulses", he said.
A growing number of people have sought treatment in recent years for "sex addiction", including golf legend Tiger Woods after his history of multiple extra-marital affairs came to light in 2009.
In France, three to six percent of the adult population -- 84 percent of them men -- are afflicted, according to Florence Thibaut, a researcher at the French National Institute of Health and Medical Research.
So far, extreme sexual desire has yet to be formally classified by either French or American medical establishments as a form of addiction, alongside tobacco, alcohol, drugs or even video gaming.
That may change, however, with the upcoming fifth edition of the American Psychiatric Association's Diagnostic and Statistical Manual of Mental Disorders, informally known as DSM-5.
Used as a psychiatric reference around the world, the diagnostic bible is reviewing the inclusion of a new category called "hypersexual disorder", according to the APA's website.
"These men and women are presented to clinicians because of recurrent, 'out of control' sexual behaviors that are not inherently socially deviant," the relevant work group said in describing patients who seek treatment.
One of the signature traits of hypersexual disorder, the proposed entry says, is "repetitively engaging in sexual behavior while disregarding the risk for physical or emotional harm to self or others".
Controversy over the diagnosis, however, is likely to push the entry into the DSM-5's appendix rather than the main body of the text, researchers and doctors participating in the review have said.
For forensic psychiatrist Roland Coutanceau, an act of seduction rarely spills over into an act of violence. "Most sexual predators are not seducers," he said by phone.
All these experts were reluctant to speculate on the case of Strauss-Kahn but agreed that they did not see the clear imprint of addiction in its clinical sense.
"Perhaps one needs to consider the sexuality of men with power who can lose touch with reality and what is, or is not, allowed," said Matysiak.
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