unlike the eye, the ear has no lids. Therefore noise penetrates without obstruction. Loud noises instinctively signal danger to any organism with a hearing mechanism, including human beings. In response, heartbeat and respiration accelerate. In fact, there is a general increase in functioning brought about by the flow of adrenalin released in response to fear. Because noise is unavoidable in a complex industrial society, we are constantly responding in the same ways that we would respond to anger. Recently, researchers have concluded that noise and our response may be much more than an annoyance. It may be a serious  threat to physical and psychological health and well-being causing  damage not only to the ear and brain but also to the heart and stomach. We have long known that hearing loss is America's number one  nonfatal health problem, but now we are learning that some of us with heart disease and ulcer may be victims of noise as well.