Love may be as good as morphine

That rush of good feelings you have in the first few months of being in love don't just put you in a better mood; love may actually be a painkiller, researchers suggest in a new study in the journal PLoS ONE.

"Finding pleasure in activities, and with the one you’re with, can have multiple benefits, including reducing your pain," said senior author Dr. Sean Mackey, chief of the Division of Pain Management at Stanford University School of Medicine.

The study looked at 15 undergraduates – both men and women – between ages 19 and 21, all of whom were in the "early phases of passionate love," having been in a relationship anywhere from a few months to a year. This is a small sample size, but not unusual for a study involving functional magnetic resonance imaging (fMRI).

Participants were asked to bring in photos of their beloved and an acquaintance who was equally attractive. While viewing these photos, a computer-controlled stimulator made them feel pain in the palm of their hand that felt akin to burning oneself on a hot pan, but in a safe way and without causing any actual damage, Mackey said. They were also asked to answer distracting questions while the pain was applied. The fMRI scanner allowed researchers to examine what brain systems were involved during each condition.

The magnitude of pain relief when participants thought about their beloved was comparable to morphine and other clinical painkillers, Mackey said. However, he cautioned that this is not a study about chronic pain, merely pain applied for 30 seconds at a time in an artificial setting.

The results suggest that thinking about your beloved and having a non-love-related distraction lower the perception of pain, but the love effect involves entirely different brain systems, Mackey said. This speaks to the complexity of the human brain, he said.

Distraction involves high level cortical systems that are involved with conducting tasks, Mackey said. Love, on the other hand, involves systems dependent on dopamine, a brain chemical that causes us to feel good and crave things. The dopamine rush also happens upon eating a piece of chocolate, or, in more extreme forms, taking a hit of cocaine or heroin. Drugs that directly engage this brain chemical tend to be highly addictive, he said.

Other recent research also has described love as an addiction. A Journal of Neurophysiology study suggested that love involves the same area of the brain associated with cocaine and nicotine addiction; that's one example of recent findings on the science of love.

Mackey also suspects there is some effect of pain heightening in those who have recently experienced a breakup of some kind, having seen increases in pain among patients who went through divorces. But that was not part of this study.

Future research in this area might additionally explore whether the affection of people who have been in committed relationships for much longer, perhaps decades, can also relieve pain. Other areas to explore are the brain systems that are involved when it comes to homosexual love, the bond between mother and child, and platonic friendships, Mackey said.

"Trying to maintain that spark in one’s relationship and that passion, engaging those reward systems, may very well work the same way as being in that early phase of love," he said.