A neuropsychosexual approach to infidelity

Falling in love is a much longed for experience for many people in our society, and at certain life stages it may become a priority to find someone and begin to develop a romantic partnership. While films and poems describe the thrill of finding the object of passionate love, popular culture is also replete with books and articles on how to manage distressing couple issues. Seeking and developing a relationship is exciting, but, after the early intensity, the challenge is to maintain the intimacy over time: the pain of unmet needs and shattered beliefs when difficulties emerge is considerable. Why we fall in love with a particular person, how we make the choice and what we really experience, is a source of ongoing fascination.

Although as a topic neuroscience may appear antithetical to talking therapies, I see psychosexual therapy as an approach that can potentially address complex relationship difficulties more effectively when it embraces scientific advances, rather than relying solely on well-described techniques. I also think we can manage our interpersonal responses better when we have some understanding of how the brain works when we experience strong emotions. I suggest the use of the term 'neuropsychosexual' to describe an approach to sexual and relationship issues that contains an understanding of brain phenomena, and their role in the expression of love and sex.

Sex in the Brain gives an overview of the neurobiological mechanisms involved in love, sex, and intimacy, and considers how neuroscience has the potential to enhance relationships and psychosexual therapy through the insights offered from this expanding area of research. Brief case vignettes (composites from my work over the years) show how including neurobiological descriptions of psychological states can add depth to therapy practice.

Complex underpinnings

Debates abound on whether humans are naturally monogamous, and one suggestion is that we have evolved to seek and prefer social monogamy without necessarily managing sexual monogamy (de Boer et al., 2012). Social monogamy includes loving relationships, selective attachments, long-term bonds, family groups, and wariness or aggression to strangers. Issues around infidelity raise significant cultural, personal, and moral questions. Terms such as extra-dyadic sex and extra-pair mating are used in research, where infidelity is defined as including any physical sexual activity with an individual other than one's current, self-identified committed relationship partner. Expectations of fidelity are strong in our society, and infidelity causes immense distress for everyone involved. Dissatisfaction with the primary relationship, attachment style, and opportunity are among the key factors explored to account for infidelity, and self-regulation and commitment to the pair bond are also a focus of research. Neuroscience has added to the infidelity topic, drawing on genetic, fMRI studies, and animal models to identify the possible genetic and biological mechanisms associated with sex outside the committed partnership.

Fisher's work (2004) described the three brain systems underpinning human reproductive strategy: lust, or sex drive (dependent on oestrogen and testosterone), which evolved to motivate sexual behaviour in general; romantic attraction (dependent on DA, noradrenaline, and serotonin), which focuses mating energy on a specific selected partner; and attachment (dependent on oxytocin and vasopressin). Although these three basic neural systems interact with one another and many other brain systems, they can impact separately on emotions, making it biologically possible to express deep feelings of attachment for one partner, while feeling intense romantic love for another individual, while also feeling a sex drive for even more extra-dyadic partners (Tsapelas et al., 2010).

Many genetic studies have examined the brain's DA reward pathway. Acevedo et al. (2012) found that activity in the ventral tegmental area (where DA originates) was associated with long-term romantic love, specifically the dopamine receptors, which come in different forms. Uncommitted and risky sexual behaviours have similarly been linked to genes coding for motivation and reward in the brain (e.g. Garcia et al., 2010).

Other factors apart from genes are relevant to all human traits, and how genes impact on behaviour across the life course will depend to a considerable degree on the epigenome – the chemical marks that influence whether or not the gene is expressed. Childhood experiences rearrange the epigenome, and the study of environmental factors that contribute to the release of information carried by genes is known as epigenetics. On a positive note, science has revealed that epigenetic changes are reversible over time, confirming the value of therapeutic work in this painful area of relationship management.

Couples struggling with infidelity generally present with significant emotional hurt, abandonment fears, and anger issues. Some people decide that staying with a partner is too difficult when they experience betrayal, while others work hard to tolerate and accept what has occurred. Understanding the different neural correlates underpinning lust, attraction, and attachment can be part of the healing process in some cases, when the hurt person is able to accept they are loved even though their partner has been involved with someone else. Awareness by clinicians of the genetic evidence could increase understanding of the difficulty experienced by the acting-out partner, while at the same time managing intense emotional expression during couple sessions.

Case vignette: Chris and Kelly

Chris and Kelly are in their late fifties and had been married for three years when Kelly discovered text messages on Chris's phone, indicating he was involved with another woman. She was very shocked and confronted Chris at once. Both partners had been married unhappily before and had met through an online dating site. Part of Kelly's distress was because their sex life was enjoyable and remained active, yet Chris had sought a sexual outlet elsewhere. He was a businessman who travelled for work, and had met up with one of the women he had dated while searching for a partner online. In Chris's background, his father, whom he was close to, was a womaniser whose affairs caused his mother immense distress. He recalled regular heated arguments between his parents as a child, when his mother shouted a lot, and he would lie in bed wishing she would stop. Although he was upset at the thought of causing pain to Kelly, he convinced himself it would not matter, saying the other woman was fun but unimportant. When confronted with the infidelity he was clear that he wished to stay with Kelly, and he immediately ended the other relationship.

Kelly came from a family who had struggled financially, due to her parents' job problems. She was exposed to her mother's anger with her father, who had a gambling habit which he lied about, and which caused many days off work. She was determined to earn her own money and not live with a man who deceived her. For Kelly the infidelity was a profound betrayal. Chris struggled to understand her reactions because he insisted she was the one he loved, and he wanted to stay with her. Describing the different brain systems underpinning the sex drive, attraction, and attachment was helpful to the couple, although painful for Kelly. 

While addressing different ways of relating that could bring more emotional closeness, we also focused on how Chris was repeating the pattern of his father's infidelity, which on a conscious level he had no wish to do. We talked about how Chris could be making choices for himself and for Kelly to avoid the impact of another betrayal, which Kelly said would definitely lead to divorce. Chris desperately did not want to lose Kelly and was keen to hear about the ability of prefrontal cortex reasoning to overcome emotions, such as feeling attracted to another person. Despite uncertainties that kept arising, therapy helped both partners to understand what had happened and how they could maintain their couple bond.

Adding depth to the therapeutic dialogue

Managing intimate sexual behaviours causes concern to most of us over the life course, and finding out more about the brain processes involved in relationship dynamics might help to address issues and to negotiate the inevitable changes. Many complex factors interweave to create the powerful human drive to love, connect, relate, and mate with one another. Neuroscience has begun to explore these basic urges, and my aim with this book was to describe the current research as it pertains to love, intimacy, and sex. 

Psychosexual and couple work, as with all therapy, aims to create emotional and behavioural changes. Intimate relationships require the ongoing creation of new neural pathways, a process that has been called the interpersonal sculpting of the brain (Cozolino, 2017). People need time in each other's company for this to happen. Regular communication and physical contact facilitate the biobehavioural synchrony that characterises harmonious relationships, including intimacy and pleasurable sex. Siegel (2010) stresses the role of practice and repetition for lasting change to be achieved. Repetition stimulates the growth of myelin sheaths round neurons to greatly increase the efficiency and speed of signals transmitted in the nervous system. Conversely, if neural pathways remain unused, they gradually fade and decay with time, as a process of synaptic pruning occurs. Discussing this with clients can give some optimism for people who want to achieve real progress. Understanding how mental training creates efficient neural networks can provide confidence for the therapist too.

I hope that others will find, as I have, that a neuropsychosexual approach can influence clinical work both subtly and directly, add depth of a different kind to the therapeutic dialogue, and provide valuable insights to clients struggling with intimacy.

References

Acevedo, B. P., Aron, A., Fisher, H. E., & Brown, L. L. (2012). Neural correlates of marital satisfaction and well-being: Reward, empathy, and affect. Clinical Neuropsychiatry: Journal of Treatment Evaluation, 9(1): 20–31.

Cozolino, L. (2017). The Neuroscience of Psychotherapy: Healing the Social Brain. New York: W. W. Norton. 

de Boer, A., van Buel, E. M., & Ter Horst, G. J. (2012). Love is more than just a kiss: A neurobiological perspective on love and affection. Neuroscience, 201: 114–124. 

Fisher, H. E. (2004). Why We Love: The Nature and Chemistry of Romantic Love. New York: Henry Holt.

Garcia, J. R., MacKillop, J., Aller, E. L., Merriwether, A. M., Wilson, D. S., & Lum, J. K. (2010). Associations between dopamine D4 receptor gene variation with both infidelity and sexual promiscuity. PLoS One, 5(11): e14162.

Siegel, D. J. (2010). Mindsight: The New Science of Personal Transformation. New York: Bantam. 

Tsapelas, I., Fisher, H. E., & Aron, A. (2010). Infidelity: when, where why. In: W. R. Cupach & B. H. Spitzberg, The Dark Side of Close Relationships II (pp. 175–196). New York: Routledge.