Sense organs- Ear- taste buds - skin touch

THE OTHER SENSES 

Man has about 3,000 taste buds. They are mainly on the tongue, although there are a few on the palate, tonsils, and pharynx. There are four primary or basic tastes sensations-sweet, bitter, sour or acid, and salt. You can't taste all flavors on all parts of the tongue. Sweet flavors register near the tip, sour on the sides, bitter on the back, and salty all over. The sense of smell is located in odor receptors in the upper passage of the nasal cavity. 

The size of the membrane containing the odor receptors is only about one-fourth square inch in man as against an area 40 times as great in the dog. The organ of smell, which can detect things at a distance, is obviously more important as a danger warning system in animals than in man. It's because of the location of the receptors that you may not smell delicate odors at first.

It takes several whiffs to get the odor into the upper nasal passage. Before you can taste anything, the substance must be moistened, and the salivary glands supply the moisture. And to be smelled, an odor must be dissolved in the mucus secreted by the nasal membranes. Smell receptors in man, although they do not have the same capacity as in lower animals, still are sensitive enough to allow you to detect a substance diluted to as much as one part in 30 billion. 

No special care is required to guard the senses of taste and smell. You may wish to read, in connection with these senses, the section dealing with care of the mouth and the nose. Touch, sometimes called the fifth sense, is actually five senses: touch, pressure, pain, heat, and cold. Skin: sensations are registered in nerve endings all over the body. Nerve fibers carry them as impulses to the spinal cord and then to the brain where all these feelings register. If you place your hand lightly on any object, the first sensation is touch.

Press harder and you sense pressure. And if the object has a rough surface and you press hard enough, you may feel pain. The senses are closely related though distinct from each other. Also in the skin are separate nerve endings to register heat and cold, which is absence of heat. A discussion of sense organs could go much further but would serve no useful purpose here. 

For example, you can feel the pain of a stomach- ache, but you can also feel hunger, which is quite different. You can also feel thirst, which is not among the sensations classically classified. Some investigators have suggested that the senses might well be divided into a dozen or more categories. In addition to the usual five-sight, hearing, taste, smell, and touch-pressure, heat, cold, and pain deserve individual categories, and so, too, the ability to sense vibration, position, and equilibrium. 

Drug addiction releif and benefits on sensory organs

There may be a sharpening of other senses-taste, smell, hearing, touch. And often various sensory impressions may appear to merge, so that colors, for example, may seem to have taste. Users report many other strange experiences, including simultaneous opposite emotions, being at once happy and sad, elated and depressed, tense and relaxed. 

At different times, there may be different effects for the same individual. Responses cannot be predicted, which is why users often describe their experiences as "good trips" and "bad trips." Some LSD users believe that since LSD heightens their senses, it makes them more creative. But this is not supported by the paintings, writings, and other creative efforts of drug users i in fact, in many cases, the works produced after drug use am poorer than before. How LSD works in the body is not yet thoroughly understood.

There is some evidence that it affects the amounts or levels of certain chemicals in the brain and changes brain electrical activity. Experiments with animals suggest that the drug may block a normal filtering process in the brain which then becomes flooded with myriad un screened sights and sounds. The dangerous effects of LSD are many. Hospitals report that some users, in a panic over their inability to cut off the effects of the drug, fear they are losing their minds. 

Some become paranoiac, developing in- creasing suspicions that people are out to harm them and control their thinking. Weeks and even months after LSD use has been stopped, some people have recurrences of the same experiences they had while using the drug and fear they are going insane.

Accidental deaths have been reported-instances of users walking in front of moving cars, convinced they were impervious to harm, and even leaping out of high windows because of a conviction they could fly. Medical experts report that the overwhelming fears and worries that may accompany an LSD experience can sometimes be disturbing enough to produce acute and even long-lasting mental illness.

Changes in chromosomes-the tiny threads in the nucleus of all cells which carry genetic information and guide reproduction-have raised concern. The changes found are actual breaks in the chromosomes, and the fear is that this may lead to birth defects in children of users.