The launch of David Simon’s new series The Deuce (starting on 26 September), has thrust pornography back into the spotlight. One of the most famous neuroscientific discoveries of the last decade probably plays a role.
This is the finding of a ‘mirror neuron’ in the cortex of a macaque monkey, so named because it fires both when the monkey sees an action and when it performs it – ‘mirroring’ behaviour it witnesses.
Cells in the human brain have been shown to exhibit similar behaviour. Dancers use their knowledge of movement to help them see it: to understand and enjoy it more. The implications for pornography are clear. Without such a system in the brain, explaining why people find watching sex arousing is difficult.
There have been a few studies demonstrating a correlation between mirror-system activation and erections in men, but it’s largely escaped systematic study. It’s hard to believe that this use has evolutionary significance, although some studies have shown that male monkeys will give up a certain amount of fruit juice to look at pictures of female monkeys’ bottoms.
Dr Daniel Glaser is director of Science Gallery at King’s College London
