CHANDIGARH, May 10: You wake up with an unknown fear that something will go wrong today. You can't explain it, you try to dismiss it from your mind as baseless and illogical but... you know it's there, it continues to gnaw at you. It's your intuition at work... and it may very well be right! The world of the sixth sense is a mysterious one, miles away from the logic your five senses understand so well, but not the weaker for being ``illogical''. It's a subject that fascinates the medical fraternity and mystics alike.

``I have a gut feeling that...'' Well, this gut feeling may be a sensation in the tummy somewhere, but it has nothing to do with the tummy. It's somewhere in the mind. Though sometimes in other parts of the body as well. But where it comes from, no one really knows.

There was once a woman who could find things ``just like that''! If someone had lost a bracelet somewhere on the beach, she could turn it up ``just like that''. But she could never understand how she did it.

Scientific researchers have now suggested the possibility of yet undiscovered internal ``receptors'' which are the seat of the sixth senses. In fact, research into the organisation of the nervous system and the brain is thrusting close to these ``psychic hiding places''.

Man is not the only creature who has a sixth sense. Animals too have a very strong sixth sense. Think of the pet dog in your neighbourhood who howled for days together before a death in the locality. There are many documented instances of this. Can dogs foresee death?

Our folklore tells us that a dog can clearly see `Yamaraj' approaching; he's frightened and howls. Then there are well documented stories of a lost pet finding its way home. No one has been able to explain how such a `homing instinct' works.

Nevertheless, science has been able to uncover, to some extent, the physical mechanisms behind some of the seemingly mysterious faculties which animals possess. A German zoologist, for instance, discovered how bees fly a straight course to flowers, even from as far as 6 kilometres away. The bees use the plane of polarised light... that is, their eyes are able to follow those sun rays which shine in a fixed direction.

Now look at fish. Fish rarely collide with each other underwater, even in the darkest of the dark. They often dart away if a fisherman on the bank so much as takes a small step. Why? It's because many fish have a sensory organ on their flanks which registers extremely slight changes in the flow of the water. These enable the fish to detect a nearby fin or even sound vibrations from above the surface of the water!

Electro magnetism, radar waves, infra red rays and inertial forces are all subtle things. But they can be measured on instruments. Maybe living creatures too register these subtle forces.

Our five senses have external and internal receivers. The Heat sense refers to the feeling of heat or the lack of it. So if you feel a heating sensation for no obvious reason in the surroundings, you need not be alarmed. You are receiving some a peculiar form of heat signal. Researchers believe that it registers on a separate system of nerves, in the centre of the spinal cord connected to patches of skin (chiefly around the middle of the body) by long thread-like nerve fibres.

The second, the Weight sense, helps us adjust ourselves to the weight of things we pick or handle. A cricketer lifts his heavy bat with such an ease. It's not only due to habit but also the sixth sense that adjusts him mentally to the weight of the bat as he perceives it. We are taken by surprise when a thing is not as heavy or as light as we ``sense'' it. The Gravity or Balance sense gives us the feeling of being `up' or `down', and tells us of our posture. Here the receptors consist of two bony boxes containing grains of calcium, one located behind each ear. Movement of the head makes the grains tumble about, striking sensitive hairs inside the boxes signalling the nervous system about how much the head is off the plumbline!

The fourth, Nearness sense, give the awareness of the presence of solid objects without sight or physical contact. It is a subtle, mysterious sense with no known receptors. But it is one of the strongest.

The last, that is the Proprioceptor sense, perceives the various parts of the body in relation to one another. This is quite different from the sense of gravity. The receiving nerves in this case have `flower spray' ends that pierce our muscles reporting how much each is stretched or flexed.

Copyright © 1997 Indian Express Newspapers (Bombay) Ltd.