Ask Mr Brain...all will be explained

PUBLISHED : Tuesday, 07 September, 1999, 12:00am
UPDATED : Tuesday, 07 September, 1999, 12:00am

Why do we laugh? And what does laughing do for us? There are several ways to think about why we laugh.

The first is that we laugh when we feel superior to others. Why do we laugh when someone trips? Perhaps it is because we feel good that it was not us.

It is not very nice, but there is an element of truth in it.

Another theory is that we laugh because we were caught off guard and were not expecting the person to trip.

Another school of thought is that laughter brings relief. Laughter frees you from the constraints of life. You let everything out and you feel better.

Laughter activates the entire cortex of the brain in the form of a negatively charged wave of electricity that sweeps through the area. When we laugh, our heart rate increases and we breathe more deeply. Chemicals called endorphins are released in our brain. Endorphins reduce the feeling of pain and affect our emotions. Laughter also activates T lymphocytes, the 'killer cells' in the immune system.

There is evidence that laughter can serve as an effective mechanism to cope with stress. People with a good sense of humour have been found to suffer less from stress. Those who respond to humour are less likely to be depressed.

Why is cosmetic surgery called 'plastic' surgery? Cosmetic surgery is very common nowadays, especially in Japan. Even men are opting for plastic surgery. There are many different kinds of plastic surgery, the more common being eye, nose and breast surgery.

Cosmetic surgery is called plastic surgery not because plastic ele ments are used. The word 'plastic' comes from the Greek word plastikos, meaning to mould or shape.

Many of the first plastic surgery operations were developed to close a difficult wound or replace tissue lost due to injury or cancer.

These procedures often involved the formation of a skin flap to reshape or mould damaged parts back into their original shape.

Why does rain sometimes have colours? In 1608, a small mountain village in France had red rain. In 1963, there was yellow rain in northeastern China. In 1979, Guangxi experienced black rain. Different factors led to the coloured precipitation.

Wind blew red dust and sand from the desert area in West Africa into the atmosphere and the dust and sand was carried by clouds across the Mediterranean Sea to France. When it rained, the dust and sand was dispersed over the French village.

The yellow rain in northeastern China was the result of yellow pollen from red pine trees being dispersed into the atmosphere and mixing with rain clouds. When it rained, the rain turned yellow.

The black rain in Guangxi was due to a forest fire that took place before the downpour.

Ashes were dispersed into the atmosphere and mixed in with the rain.