What is the connection between desire and love? This question has been one that relationship scientists and couples therapists have concerned themselves with for a long time, but the answer has remained elusive.
Recently, researcher Jim Pfaus, professor of psychology at Concordia University, co-authored a study published in the Journal of Sexual Medicine that set out to use brain imaging to try to shed some light on the differences and similarities between sexual desire and love.
It turns out that love and desire activate specific but related areas in the brain. The researchers found that two brain structures in particular, the insula and the striatum, are responsible for tracking the progression from sexual desire to love. The insula is a portion of the cerebral cortex folded deep within an area between the temporal lobe and the frontal lobe, while the striatum is located nearby, inside the forebrain.
Love and sexual desire activate different areas of the striatum. The area activated by sexual desire is usually activated by things that are inherently pleasurable, such as sex or food. The area activated by love is involved in the process of conditioning by which things paired with reward or pleasure are given inherent value. That is, as feelings of sexual desire develop into love, they are processed in a different place in the striatum.
Somewhat surprisingly, this area of the striatum is also the part of the brain that associated with drug addiction. Pfaus explains there is good reason for this. "Love is actually a habit that is formed from sexual desire as desire is rewarded. It works the same way in the brain as when people become addicted to drugs."
This habit has its pros and cons. For some, the experience can turn into an addictive process, whereby they seek out, again and again, the experience of falling in love, unable to form a long-term relationship bond. For most, however, the habit of love activates pathways in the brain that are involved in monogamy and pair bonding, and is connected to parts of the brain that are more abstract and complex – so that the experience of love is not as dependent on the physical presence of someone else. Another way of understanding it would be that desire and love are on a spectrum that evolves from integrative representations of sensation to an ultimate representation of feelings. Thus they are not the same thing, but are intimately connected.
According to Pfaus, cognitive neuroscience has given researchers a deep understanding of where intelligence and problem solving sit in the brain, but there is still a lot to discover when it comes to love. He hopes that studies such as his will not only give us a map of where these experiences are located in the brain, but perhaps more importantly deepen our understanding of how these feelings and experiences – so central to our existence as humans – grow and evolve.