Addicted to love

Addicted to love

So what exactly is going on during the rollercoaster of euphoria and despair that is falling in love?

In the brain, romantic love shows similarities to going mildly insane or suffering from obsessive compulsive disorder. Studies show that when you first fall in love, serotonin levels plummet and the brain's reward centres are flooded with dopamine. This gives a high similar to an addictive drug, creating powerful links in our minds between pleasure and the object of our affection, and meaning we crave the hit of our beloved again and again.

Lust is driven by sex hormones such as testosterone, which can go off-kilter too. As can levels of the stress hormone cortisol, and the amphetamine-like chemical phenylethlyamine, increasing excitement.

Other hormones, oxytocin and vasopressin, kick in later and appear to be crucial for forming long-term partnerships. Couples who have been together for several years show increased brain activity associated with these chemicals, when they look at pictures of their partner. Oxytocin is produced when couples have sex and touch, kiss and massage each other - the hormone makes us more trusting, helps overcome "social fear" and is important for bonding.

Brain scans of people in love show that the old adage "love is blind" really is true. While the dopamine reward areas are excited in love, regions linked with negative emotions and critical social judgement switch off.