In one of the largest studies of its kind ever published, US psychologists have found a particular aspect of personality in men and women, predicts what the researchers refer to as 'hypersexuality'.

The 'hypersexual' have more sexual partners than the rest of the population, fantasise more about others than their current partner, and tend to favour more sex without love. They take greater pleasure in casual sex with different partners, and don't need attachment to enjoy lovemaking.

Hypersexuality was found strongly linked with a particular aspect of personality.

Another especially intriguing aspect of this research, conducted on 482 people aged 17-56 years old, was that this personality feature applied equally to both men and women, in predicting hypersexuality.

Psychologists are beginning to concur that it's this unique element of character which most powerfully predicts higher numbers of different sexual partners, as well as impulsive one night stands, and a gamut of risky sexual behaviours.

This character trait is - Psychopathy.

Psychopaths are linked in the popular imagination with criminals and sex offenders, but psychologists Rebecca Kastner and Martin Sellbom from the University of Alabama, who conducted this study, entitled, 'Hypersexuality in college students: The role of psychopathy', emphasise they were studying features of psychopathy which are more common in the general population than may be realised.

Psychologists believe everyone falls somewhere along the spectrum of psychopathy, and have more or less of these traits. It would seem the more aspects of psychopathy are reflected in a person's character, the more they embrace 'hypersexuality'.

The psychopathic personality is characterised by a callous and manipulative approach to others, lack of remorse, plus deceit all covered up by superficial charm. Not a particularly alluring package at first glance, so psychologists have been probing deeper inside the psychopath's mind, unlocking the secret of their success in the bedroom.

Rebecca Kastner and Martin Sellbom found from their study, just published in the academic journal 'Personality and Individual Differences', that it's the 'Fearless-Dominance' aspect of psychopathy, combined with the 'Impulsive-Antisocial' element, which actually explains why psychopaths dominate the medal tables in the sexual Olympics.

Fearlessness and dominance means psychopaths appear charming, grandiose, risk-taking with little regard for consequences, combined with absence of anxiety. They don't anticipate and aren't bothered by performance failure - which is a consideration that appears to put the rest of us off being too hypersexual. These factors can also be positively associated with a hard work ethic, even heroism, confidence and achievement; all characteristics that women value in a male partner.

Kastner and Sellbom also contend it's the relative immunity from stress and fearlessness of psychopaths, which explains why they are less inhibited than the rest of us. As a result, they seek thrilling, dangerous, and otherwise anxiety provoking sexual situations.

Psychologists argue its the 'impulsive-antisocial' element of their character which ensures they use others ruthlessly for their own gain. This exploitative social style helps generate the higher number of sex partners and short-term mating. Impulsivity means as well they act on possible reward (i.e., sex) without considering the consequences. They also disregard social norms and standards (e.g., one shall not be promiscuous, break the law, etc.).

One theory is that male and female psychopaths end up hypersexual through different routes via contrasts in personality - it's the antisocial aspect in men, but instead the impulsive thrill seeking in women.

Psychologist David Kosson and colleagues from the University of North Carolina at Greensboro, found in their research that of more psychopathic individuals, 58% report using flattery, 40% argument and 40% exploitation of an intoxicated person, to achieve sex. These figures from this study, entitled 'Psychopathy-Related Traits Predict Self-Reported Sexual Aggression Among College Men', and published in the 'Journal of Interpersonal Violence', were about twice higher than in the non-psychopathic.

Luna Muñoz and colleagues from the University of Central Lancashire researched sexually coercive tactics after being turned down by a partner, including sexual arousal and touching; emotional manipulation; exploiting by intoxication; and physical force. The study entitled, 'Sexually Coercive Tactics Used by University Students: A Clear Role for Primary Psychopathy', and published in the 'Journal of Personality Disorders', found men and women rated high on psychopathy were more likely to be sexually coercive.

Based on our clinical experience, we find psychopathic women are more likely than others to engage in sexual coercion, when they encounter conflict in their relationship. Clashes, in their minds, are solved by sex. Perhaps psychopathic women view sex as a tool for manipulating others and achieving what they want, whilst psychopathic men favour deceitful emotional engagement.

One of Dr Helinä Häkkänen-Nyholm's clients described (she reports this with his permission) an attempt to leave the marital home after announcing his intention to divorce, following years of mistreatment, betrayal and abuse. While standing in the corridor, he witnessed his wife undressing and suggesting sex.

Research has found psychopaths are also more interested in violent, coercive, and sadistic sex, so this insight might unlock one of the secrets to the success of the best-selling novel '50 Shades of Grey', where sado-masochistic coupling appears to be part of the appeal of this publishing phenomenon.

But this latest study reveals that any medal winning sexual athlete has to be more psychopathic than we had realised before.

So does the best-selling novel Fifty Shades of Grey, with its sado-masochistic themes, expose that deep in the recesses of all our personalities, is a sneaking admiration for psychopathic success in the bedroom?