I just watched an interesting programme on TV

I just watched an interesting programme on TV. It was an experiment about the brain. The guy asked if light travels faster than sound, why don't they use a light to start races instead of a gun. He had 5 guys line up at the starting blocks for a race, he then made the started fire a gun for them to start the race. He then had the same guys get ready to run a race, but the starter this time flashed a light. The reaction time with the light was almost twice slower than their reaction when the gun was fired. He thinks that the brain takes longer to process information through sight, more than sound. Very interesting.

sound is classical conditioning.

read russian psychologist Ivan Pavlov

and his Dog and the bell ringing !

You can easily test this yourself here:

http://cognitivefun.net/test/1

http://cognitivefun.net/test/16

Why do you react to sound faster? Because it takes the human body longer to turn light into a biochemical signal, than it does to convert sound. When you hear a sound, this involves the sound waves hitting your ear, and so tickling receptor cells which create a bicochemical signal which goes directly to your brain. Simple. One step.

When a photon of light hits the eye, however, this triggers a long chain reaction of proteins and cells and enzymes, each passing on the signal throughout the body, until, very late in the game, a biochemical signal is generated and sent to the brain.

But it's wrong to say that "racers respond slower to light than a sound". If the gun and light were positioned just a few meters away from the racer (like in car racing), the human would react to the light faster than the sound (because the light would travel faster to the eye, negating the speed gained by the body when it converts sound to a signal).