And now, a group of researchers in Japan have unravelled the reason why women love to adorn themselves with make-up. The reason: Women anticipate 'a rush of optimism and anticipation' as they prepare to wear make-up.

Led by Dr Ken Mogi, the researchers carried out the study and found that there are distinct cognitive activities involved in a woman's perception of her face with and without make-up.

With the help of a brain scanner, the researchers were able to monitor activity in the caudate nucleus of the brain of women and found that when a woman sees her own face without make-up, she anticipates how she will eventually appear to others and a 'reward system' is activated, releasing dopamine to give sensations of pleasure.

Keishi Saruwatari of cosmetic giant Kanebo, which commissioned the study, said, “We know from previous research that when this area of the brain is activated we can derive pleasure from certain activities. We interpret that as meaning that when a woman looks at her face she is imagining how she will look when she has applied her make-up.”

Although the study focused on female responses, the researchers believe similar feelings may be at work when a man shaves or puts on cologne on the body.

“We can now not only put a functional value on a product now, but also measure the emotional appeal. By using quantifiable research, we will be able to strengthen emotional value of a product and develop more appealing versions,” added co-researcher Yasuhiko Tanaka.