Why women fall for St Valentine's Day and men just have to PEA; Early

0 Comments | Sunday Herald, The, Feb 8, 2004 | by Sarah-Kate Templeton

Men who shun stable relationships for a string of passionate flings may suffer from a hormonal imbalance that makes them susceptible to philandering.

Scientists say they cannot rule out the possibility that an "addiction" to chemical changes in the brain, which are triggered by the excitement of dating, makes some men incapable of settling down with one partner.

These men may become so hooked on the adrenaline rush of the first date that they refuse to trade in the highs of the initial stage of a relationship for the companionship offered by a long-term love.

There are three main hormonal stages of a romance. Stage one is the buzz of the first date. This is caused by the release in the brain of a chemical called phenylethylamine (PEA), which has a similar effect on mood to that of amphetamines. This is rapidly followed in the next stage by the adrenal glands releasing adrenaline and noradrenaline - stress hormones that are part of the body's "fight or flight" response to potentially threatening situations.

If the relationship is sustained, it goes into a third phase when another group of hormones predominate. These are bonding chemicals, such as oxytocin and possibly endorphins, which keep the couple together. However, scientists believe it is possible that some men and woman get so hooked on the powerful chemicals involved in the excitement of the first stages of a relationship that they cannot settle down to the third stage with a partner. Instead, they want to experience the rush of the first date all over again.

Dr Glenn Wilson, a psychologist at the Institute of Psychiatry at King's College London, said: "There are love addicts or love junkies who live on the adrenaline phase and, as soon as that is over, they look for someone else. I am sure there are people like that. Whether they will settle down when their hormones are no longer bothering them is not known.

"There may be people who are addicted to dating in this way. There are some people who look for these chemical changes in the brain and need them more than others. Men are more susceptible than women."

Professor Gareth Leng, of the Centre for Neuroscience at Edinburgh University, added: "It is clearly a reasonable hypothesis that differences in behaviour, like the ability to make successful long- term bonds, reflects very specific differences in the brain, like the pattern of expression of oxytocin receptors. This might be inherited, or it might be a difference induced by environmental factors.

"This shouldn't be too controversial in that we would expect major differences in an important behaviour pattern to reflect some difference in brain function."

And scientists think womanisers, and man-eaters, may be driven by the same craving for the "adrenaline rush" as those who participate in extreme sports such as bungee jumping and white-water rafting.

Leng added: "There are obvious parallels, and beyond that there are very clear associations in the circuitry of the brain. The noradrenaline pathway is activated in 'stressful' circumstances, as well as by stimulation of the reproductive tract."

Professor Stanton Newman, head of the department of psychiatry and behavioural sciences at University College London, agrees it is possible that bungee jumpers and womanisers are driven by the same cravings for particular chemicals in the brain, but points out that we have no research to prove this.

"Long-term relationships don't provide that adrenaline and excitement of the chase.

"There are some people who never settle in a relationship for long. How different are they to bungee jumpers? It has been suggested that this is due to the excitement associated with the adrenaline hormone, but we don't really know."

When someone is going on a first date, their heart races in the same way as if they were nervous about a job interview, of if they were threatened with injury or violence.

Professor Martin Cowie, a cardiologist at Imperial College London, says the nervous tension before a date is more pleasurable, but the physical changes in the body are the same during any major challenge or risk.

"If someone was aggressive towards you, or if you were going for a job interview, you would experience the same reaction. The feeling before a date is more pleasurable but, as cardiologists looking at the behaviour of the heart, we wouldn't be able to see the difference.

"Some people become junkies for this feeling; they become addicted to that adrenaline surge. It is like being on a roller-coaster ride, you want to go back on again.

"In a more mature relationship these feelings are compensated for by companionship."

Prof Cowie will be speaking at the Heartache of St Valentine's Day at the Dana Centre, London, on Wednesday. Dr Wilson and Prof Leng will be speaking at Science in Love at the Dana Centre on Friday