geijlsngi15 'Our brains are very sensitive to the social and emotional significance of laughter.

'During our study, when participants heard a laugh that was posed, they activated regions of the brain associated with mentalising in an attempt to understand the other person's emotional and mental state.'

The study goes a long way to explain why people can easily spot when someone is forcing laughter.

Dr McGettigan added: 'Some of the participants engaged parts of the brain that also control movements and detect sensation.

'These individuals were more accurate at telling which of the laughs were posed, and which were real, when we tested them after their scan.

'This suggests that as listeners, 'trying out' how a laugh would feel if we produced it ourselves might be a useful mechanism for understanding its meaning.'