Regardless how many sexual partners you've had, you may still benefit from figuring out the extent to which you're wired for pair bonding. Being a pair-bonder, by the way, doesn't guarantee "happily ever after." It means socially monogamous: having the capacity to fall in love and the desire to bond, at least for a time. In contrast, most mammal species are like bonobo chimps and rats; they mate and move on. The reasons for the differences lie in brain structure.Despite our capacity for promiscuity, we humans are a pair-bonding species. It shows up in our powerful hankering for touch and ongoing companionship—and makes perfect sense, as our offspring benefit from parents who hang around with each other for more than one estrous cycle. (For a solid analysis of human pair bonding, see "Your Sexy Brain" in The Compass of Pleasure.) As with any trait, however, there are always outliers (atypical individuals). So how do you know where you are on the pair-bonder spectrum? And what does it mean in terms of finding contentment?Consider a recent poll of more than a thousand middle-aged or older couples in committed, long-term relationships from five countries. Said the researchers, "The overall levels of relationship happiness were high in this study." So, what did these couples say makes their relationships most satisfying (i.e., likely to last)?For men, frequent kissing and cuddling and frequent sexual caressing by a partner each increased the odds of reporting relationship happiness by a factor of approximately 3. (Specifically 3.0 and 3.11, respectively. For women the predictive strength of each was only 1.59 and 1.35.) As the researchers concluded, there's a "need for reconsideration of the role of physical affection and its meanings" by gender. In another study, even young guys associated romantic stimuli more than sexual stimuli with a pleasant condition.Duration of relationship also had a significant and positive effect on relationship happiness. And men who had had fewer partners reported greater sexual satisfaction. Are some guys just wired for monogamy? Does extended closeness increase satisfaction? What is the link between variety and dissatisfaction? (More in a moment.)Highly valuing orgasm and frequency of sex were not strong predictors of relationship happiness. However, over all, both spouses rated their partner's orgasm as a more important priority than their own. In other words, those who pair up contentedly over the long haul seem to value affectionate and arousing touch, sexual responsiveness, and, perhaps, a generous mindset more than orgasm itself.What does your brain say, and are you hearing it clearly?Monogamy and infidelity often correlate with feelings of contentment or restlessness. These feelings arise in a primitive group of structures in the brain known as the reward circuitry. Wherever you fall on the pair-bonder spectrum, how you get your good feelings can reveal how you are wired. If you are primarily focused on living out your sexual fantasies, and novel partners are your biggest aphrodisiac, you may be more wired for riskier, hit-or-miss sex than long-term monogamy.In the alternative, you may be a pair bonder whose pleasure response has been numbed by intense sexual stimulation—or even addiction. In this regard, a new study found that significant predictors of male infidelity are: propensity for sexual excitation (becoming easily aroused by many triggers and situations) and fear of sexual performance failure. Both can be symptoms of overstimulation. Novelty and risk may then act as desperately needed aphrodisiacs because they release extra dopamine. Once balance in the brain is restored, extreme stimulation often becomes unnecessary for sexual performance, and contented monogamy is much easier.In any event, if you find affection, sexy touch and close companionship particularly arousing and satisfying, then you are probably not a restless outlier on the pair-bonder spectrum—even if you have multiple partners over time. Pair bonders adore sex, of course, but for them partner responsiveness and receptivity seem to be especially pleasurable and reassuring. This appears to be true of other pair-bonding primates as well.Are you wired like the long-term couples described above? If so, you may not be thriving in today's culture. Pair-bonder strengths, such as a need for tenderness to respond sexually, can appear to be a weakness in today's sexual milieu. Here are four areas where the standard advice could backfire for you:1. 'If it feels good do it' can lead to addictionBelieve it or not, if you have very strong pair-bond wiring, you may be particularly vulnerable to getting hooked—not just on online erotica, but also on other things. The reason is biological. Too much intense stimulation can "hijack" the very brain mechanism that evolved to encourage pair bonding. For example, pair-bonding (prairie) voles are particularly likely to go for addictive substances (unlike non-pair-bonding voles). Yet paired prairie voles have no interest in drugs.It's almost as if the reward circuitry of a pair bonder has a "little hole" crying out to be filled by a pair bond (even if the individual never bonds).In the absence of contented union, some pair bonders will grab just about anything to fill that "hole."And some won't discover they are pair bonders until they give up their love-substitutes. As one guy said:Goal: Within the next academic year, acquire a legit, dependable cuddle-buddy. It's likely that this means a girlfriend. Fine by me! Just want some TLC. God, it's so different for me to talk like this. For years I've been a porn-obsessed, introverted weirdo, who was completely mystified by the fact that people can like each other so much. Now I'm turning into one of them.