The Science of Pleasure

We’re all hedonists at heart. At every point in history and in every part of the world, humans have always managed to find ways of getting high and having fun to excess. But what’s really behind all that? What makes us do it?

In the last of the Edinburgh International Science Festival’s adult-themed presentations, Dr Paul Martin, behavioural biologist and writer on subjects as varied as moral philosophy, literature and happiness, spoke about the topic of his latest book: the biological basis of pleasure, how it operates and the history of pleasure through the ages.

At a very basic level, pleasure originates from survival mechanisms, and the things which give us pleasure, such as sex, food and social interaction, were generally associated with whatever stood to give humans a better chance of living long enough to have children. The experience of pleasure is self-limiting and tends to diminish with exposure, forcing us to go out and find new (and probably more extreme) ways of having fun.

According to Dr Martin pleasure is a bit of a harmless short-term pat on the head by our endorphins and quite different from its evil twin: desire. If pleasure is about liking something, then desire is about the wanting; the motivating driving force that means you just have to have it. Although intrinsically linked, biologically speaking desire is associated with dopamine levels in the reward centres of the brain, and while it serves a massively important role in motivation and learning, artificial dopamine production (e.g. through drugs like nicotine) can over-ride common sense and lead to addiction. At that point, the behaviour at the heart of it has very little to do with liking anything at all.

Dr Martin himself is a great speaker and his background in popular science was very helpful in keeping the audience entertained. Thankfully he didn’t fixate too much on the old cliché of chocolate being better than sex (who are those people anyway?), and was fairly amused himself by the accounts of experimentalists masturbating to orgasm within MRI machines to determine which parts of the brain were most active during sex. On the point of drugs, it was also interesting to note that when they are listed in order of addictive qualities and damage to the body, some of the worst offenders are legal. LSD, ecstasy and some other current A-listers are much further down the list. If criminalisation was more sensibly based on harm to the body, then things would be much different.

The presentation ended refreshingly and non-judgmentally with the message of what we enjoy is generally good for us, so c’est la vie! In all this 21st century liberalism, what does Dr Martin actually recommend for a full and healthy life? Well, rather disappointingly he suggests relatively minor pleasures which can be done often, cheaply and free from guilt: sex (preferably with one at least one other person), daily doses of caffeine, naps during the day and plenty of sleep at night.

This final lecture of the series was a nice overview of the subject for those without much of a science background but had just enough real content to keep the scientists among us happy. The best bits of Dr Martin’s research, covering the notable omissions of fetishes and the more interesting and complicated vices, are likely to be found in his new book and on the strength of this, it could be worth tracking it down.