How Can the Love Hormone Lead to Violence?

Most of us have dreamt of having a personal genie. We summon the genie, it grants our wishes, and our lives get better. But we forget that our genie is not bent on improving our lives. The same genie can make you a hero or a villain; grateful or green with envy; cooperative or antagonistic. It all depends on how you ask your question.

On the heels of research showing these positive and negative responses to the hormone oxytocin, we have a new genie in a bottle. Instead of rubbing a lamp to summon our genie, we sniff nasal spray. And with oxytocin nasal spray showing impressive benefits in offsetting deficits associated with certain mental conditions, it is time for researchers to get a grip on understanding when oxytocin will inspire us toward benevolence or malice.

Oxytocin motivates bonding. But personality traits and situations can bend oxytocin’s influence. For example, people use different strategies to maintain their relationships. Most people act nice, forgive, and adapt to their partner’s needs. Others dominate their relationship partners, pummeling them into submission. Oxytocin might affect these two groups of people differently. The nice guys and gals should continue their efforts to keep their relationship together by acting nice. The dominators, in contrast, might go on the offensive and try to dominate their partners.

To test this hypothesis, my colleagues and I randomly assigned college students to sniff either a placebo or oxytocin. The students waited patiently as the oxytocin took effect. While they waited, they completed some uncomfortable activities meant to provoke an aggressive response. They gave a stressful speech and also put an icy bandage on their foreheads. Next, participants reported their aggressive intentions toward a current or recent romantic partner. Some example items were “slap my partner” and “push or shove my partner.”

Could the love hormone lead to violence? It could. Oxytocin increased aggressive intentions, but the effect only occurred among those who were predisposed toward aggression. The implication is that aggressive people try to keep their romantic partners close by dominating them. When they get a boost of oxytocin, it triggers an aggressive response.

Oxytocin continues to inspire interest and confusion. We’re hard-wired to connect, and oxytocin can help make that happen. But this study shows that it isn’t enough to look at people’s oxytocin levels to know if they will act nice or aggressive. By understanding their personality traits, we can better predict whether the love hormone will promote benevolence or violence.