When we studied optics in school, we learned about conductors and reflectors. Those that conduct light are called transparent objects; those that do not conduct or transmit light are called opaque. One of the signs of an opaque object is that it creates a shadow when it is struck by light. Our body is transparent to higher energy photons such as x-rays and laser. But, it is opaque to visible light (it produces shadow.) ; or is it?

A group of scientists under Prof. Kaznachejew conducted some unusual experiments at the Institute for clinical and Experimental Medicine, in Novosibirsk, USSR. They directed a focused beam of light into different parts of the human body. The objective was to measure the skin reaction to radiation in the visible light spectrum. They used a simple laboratory light, equipped with several light filters. During this experiment, the experimenters saw a strong light signal, a tiny speck of light, at a not illuminated area about 10 centimeters distant from the illuminated surface. To their surprise, they noticed that the spot of the light had spread under the human skin (the strength of the light signal was monitored by a photo-metric device, supported by a luminance microscope with a photo multiplier).

In order to understand this phenomena better and to better classify it, follow-up experiments were conducted with better equipment. They found that only certain parts of the body are able to conduct the light entering it. This "light sensitive regions" coincided with the well-known acupuncture points and meridians on the body surface. (Please refer to the section on Acupuncture for a description of the meridians and a schematic view of the 12 meridians in the human body.) The traditional Chinese defines 365 main acupuncture points (which actually are holes which provide access to the meridians or channels which control body's vital organs.) Historically, acupuncture points were believed to be holes that allow entry into channels. These holes provide us gateways to influence, redirect, increase, or decrease body's vital substance, qi, thus correcting many of the imbalances.

The experiments at Novosibirsk did demonstrate that light will only propagate between points of the same acupuncture circuit. If the light source is moved by as little as 3-4 millimeters distant from the acupuncture point, the signal to the photomultiplier disappears at once. The light path through the human body was found to be dependent on the spectral range of the light used. The white light (a mixture of all colors) propagated the best , followed by red and blue. Green light had traveled the least.

If a living organism is exposed to visible light at the critical points, the light can travel immense distances within the body as shown in the routing of the meridians. We may think of the meridians as a "light distribution system," similar to a fiber optics system used in modern communication systems. In a fiber optic channel, the light can travel even around bends and corners by bouncing and reflecting. If one accept this light conducting theory, then we can explain the claim made by some individuals that they can sense colors and differentiate texture just by touching!

Two American scientists, Dina F. Mandoley and Winslow R.Briggs, found that light can travel through plants (Scientific American, August 1984). They illuminated the end of a barley stem with red light of a helium-neon laser. They found that the barley stem conducted the light for a distance of 4.5 centimeters. The light was traced visually and with the aid of a photo multiplier at the dark end of the stem.

From these observations, it has been postulated that the living beings are sensitive to the changes in intensity of incident light. In fact, the light may have a profound influence on the cycles of life. The entire internal system of light guiding channels is adapted to the electromagnetic environment provided by the sun and is an additional aid to survival. It is also possible that the organism uses the light to sense the changes to its external environment and use it to regulate the function of different body parts. For instance, plants do not have a nervous system such as that present in animal and humans. So, the plants may be using these "light channels" as a pseudo nervous system. This can explain why a plant will die if it does not get enough sunlight (Of course, the plants cannot make their food in the absence of light.) Within the human organism, the inner light guide system is, perhaps, a remnant of a much older regulatory system, which was inherited from an earlier state of evolution from a time where nervous systems in living organism were either undeveloped or not in existence at all.