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Understanding Systemic Noise Trauma

This article will tell you the following:

  • How noise traumatizes people
  • Why noise traumatizes some people but not others

Noise and the Autonomic Nervous System

If you want to understand how noise injures people, physiologically, socially, and psychologically, and you are hoping to make sense of the Symptoms & Side Effects of Noise poster, you first need to understand that the human body has a mind of its own, by which I mean that the inner workings of our bodies -- like breathing, digestion, the regulation of hormonal levels, alterations in blood flow, and the beating of our hearts, among others -- are all regulated below the level of conscious awareness.

These inner workings of the human body are part of something called the autonomic nervous system, which is closely linked to the endocrine system. The more you know about those two bodily systems, the easier it will be for you to understand the mechanism whereby noise destroys all that human kind holds most dear.

The unconscious processes of the human body must find their own pace because, to function optimally, the speed with which the inner body goes about its business must fluctuate if it is to effectively facilitate the activity in which we are engaged at the moment. Sometimes our hearts pound and we breathe quickly as our bodies gear-up for an exciting or strenuous event, and sometimes we relax as our inner, autonomic processes slow, in an attempt to gear-down for a non-threatening or a physically undemanding event.

It is important to note that the speeding up and the slowing down of our inner, autonomic functioning is regulated by a particular part of the brain called the hypothalamus, which sends electrical messages that cause a body-wide transformation as many of our inner processes speed up or slow down in unison.

You can't be excited or alert without your autonomic processes first shifting into a higher gear, and you can't relax or fall asleep unless your inner system slows down. Therefore, our energy level and our level of attentiveness, as well as our ability to relax and fall asleep, are all determined and limited by our autonomic processes. Even our ability to function sexually is dependent upon the capacity of our autonomic nervous systems to transform themselves as necessary, in order to carry us smoothly between the dimensions of tension and relaxation as it constantly adjusts to keep us in a state of being that is consistent with the task at hand.

To understand how people are impacted by noise force-fed into their homes, you also have to realize that emotion is physical in nature, by which I mean that you can only experience a given emotion if you are physiologically in a state that is consistent with that emotion. For example, you can't feel depressed or deeply mellow unless your autonomic processes slow way down, and you can't feel panicky or wildly elated unless they speed way up.

Therefore, emotion is a physiologically-based phenomenon in that along with fluctuations in our autonomic function come shifts in our endocrine systems, as hormones are released into our blood streams that cause us to experience a given emotion. Without the necessary hormones present in your system, you cannot experience a given emotion and, with those hormones in your blood stream, there is no way that you can avoid experiencing that particular emotion.

The emotion we feel is one with the consciousness we experience, and both are determined by the state of our autonomic and endocrine systems. Indeed, among other things, consciousness, blood flow patterns, energy level, alertness, muscle tension, digestion, and sexual functioning, along with one's emotional state, all fluctuate in tandem with our autonomic processes.

Life is such that sometimes we need to be in a highly alert, high-energy state with all of our autonomic processes revved-up, just so we can deal with the demands the outside world is making on us. Other times we need to slow down and relax, either because the moment calls for a relaxed perspective, or because our bodies are physically over-extended and we need to rest.

That is what our autonomic nervous systems do. They help us to get our bodies into the optimal gear by creating a body-wide slow-down or speed-up of our inner processes in order to create both the physiologic and the emotional state most conducive to what we need to do in order to deal effectively with the situation in which we find ourselves.

Our health, our happiness, and our ability to function effectively, then, are all dependent on our autonomic nervous systems being in proper trim, so that our level of autonomic arousal can fluctuate as our physical condition and our external circumstance dictate.

If you hope to feel good and be effective in the arena of life, then, your autonomic nervous system needs to be in just the right gear for whatever it is that you are trying to do at the moment.

Because of that, we all find ways to manipulate our autonomic nervous systems as a way of keeping them in a state that is conducive to what needs to be accomplished at that particular moment. If we need to rev-up our systems we eat sugar or have a caffeinated drink, or use tobacco, or cocaine, or one of the other stimulant drugs, while alcohol is just one of the many substances people use in order to shift their autonomic nervous systems into a lower gear.

However, pharmaceuticals are not the only way we have to regulate our autonomic nervous systems. You can speed-up or slow-down your ANS just by concentrating on something you find soothing or something you find exciting.

You can also elevate your energy level by kick-starting the ANS with a brisk walk or some other physical activity. Turning up or turning down the heat in the room can also trigger an autonomic shift, as can putting on or taking off clothing to adjust one's body temperature.

Soothing sounds like that of a small waterfall or a steady rain tend to shift most people into a more relaxed state. Silence can also result in a greatly slowed autonomic function, which is a big part of why people tend to want to have at least some kind of background sound going when they need to get things done.

Mellow music can shift you into an autonomic slowdown, which you are likely to experience as a calmer state of being, while lively music with a driving beat will tend to produce an autonomic speed-up.

Any teenager can tell you what an exhilarating rush it is to go to a concert where the sound is at saturation levels. That rush the teen concert-goer gets from the blaring music is due to the noise-induced speed-up of his autonomic functioning, which is accompanied by a release of hormones that contribute greatly to his sense of excitement.

Clearly then, noise can keep our level of autonomic arousal high enough to keep us awake and functioning in boring situations. It can even be fun and it is often exciting.

But it is no fun at all if you can't relax, or you can't have sex, or you can't get the knots out of your shoulder muscles, or sleep in your own home because the neighbor's barking dog, the din of traffic, the blare of train horns, or the roar of the local airport so disrupt the functioning of your autonomic nervous system that those things become impossible.

Click here for more information about the autonomic nervous system and how it is effected by noise.

The Definition of Stress

When a healthy person lives in healthy surroundings, his or her autonomic nervous system will frequently shift up and down the continuum of tension and relaxation, while in the process causing many of the major organs to speed-up or slow-down their rate of functioning.

However, sometimes something happens to a person that will cause their autonomic nervous system to lock into high gear for far longer than is healthy. That can happen as a result of using stimulant drugs, of course, and many other people experience a prolonged speed-up because they live in dangerous surroundings where fear is part of their everyday existence. That is to be expected, since anxious thoughts and the perception of danger tend to rev-up the ANS, and can lock the autonomic processes into a state of excitement for a period of time that far exceeds the body's capacity to adapt in a healthy fashion.

Upsetting interactions with those around you that continue over time can also trigger a prolonged autonomic imbalance.

When your body is in a state of autonomic speed-up so often that it causes you to grow emotionally distressed, and/or your body begins to break down under the all-too-frequent strain, you are said to be in a state of stress.

Stress-Related Disorders

The term stress-related disorder refers to any physical or psychological disorder that is caused by or exacerbated by stress. In other words, any physical or psychological disorder that is caused by or exacerbated by an autonomic imbalance in which the body is strained by an untenably frequent, sustained arousal of the unconscious processes.

Among the most notable stress-related disorders are anxiety disorders, phobias, panic disorder, essential hypertension, chronic depression, migraine headaches, and muscle-contraction headaches. Because the definition of a stress-related disorder includes any maladies that are exacerbated by stress, a definitive list would be huge, since most anything that can go wrong with a human being is sure to be exacerbated if that person is experiencing an autonomic disruption that makes it difficult for them to rest, relax and sleep and, thereby, recover.

Noise-Induced Trauma

Noise speeds up the ANS which is, of course, why it so often produces high blood pressure, tight muscles, and all the rest of it. If the autonomic speed-up that is causing or exacerbating your particular disorder is, in turn, caused by exposure to chronic noise, then, you are said to be suffering from noise trauma, or noise-induced trauma. Sometimes we add in the word systemic to note the fact that we are speaking of trauma that extends throughout the entire bodily system, as opposed to the local trauma that occurs when loud sound damages someone's hearing, without necessarily having any significant impact on the functioning of that person's bodywide systems.

The portion of The Symptoms and Side Effects poster, titled, The Impact of forcibly projecting noise into the home environment over time, lists some of the many stress-related disorders that can be produced by noise-induced trauma.

If your noise-induced autonomic speed-up makes you more anxious than anything else, then you will be diagnosed with an anxiety disorder, while if your noise-induced autonomic speed-up gives you high blood pressure, then, you will be diagnosed with essential hypertension. If, more than anything else, your noise-induced autonomic speed-up gives you headaches, then you will be diagnosed with muscle contraction or migraine headaches.

Thus, systemic noise trauma is itself a stress-related disorder that can manifest as any number of other stress-related disorders.

We see, then, that noise can create illness and emotional distress in the form of one or more of the stress-related disorders. It can also exacerbate any pre-existing conditions.

However, when you go to the doctor or a psychologist for help, in all probability he will point to your most pronounced symptom - the headache, the emotional labilty, your sleeping problems or whatever - and declare that the symptom is the problem, or mistakenly conclude that your most pronounced symptom is a reflection of some other, peripherally-related variable, when in reality, the symptom of exposure to chronic noise which you are experiencing is just the most pronounced manifestation of a noise-induced autonomic imbalance.

Why Some People Are Traumatized by Noise While Others Are Not

Other than the infliction of hearing damage, most people find it difficult to believe that noise can injure people simply because such a contention is not consistent with their own experience. They say, "Well, I hear a lot of different noises on and off throughout the day, and I'm not traumatized by it. In fact, I am not much bothered by it at all."

First, you need to realize that you may be more tense than you think, and noise may be effecting you more than you know. If you have long been subject to the same level of noise, then, you may have long since habituated to the level of bodily tension created by that level of exposure. In other words, because the sound is always there effecting you in about the same way, you may have lost sight of the fact that you are tense, and that the one is causing the other. In fact, many people are amazed to see the difference in their own level of tension when they are finally able to settle into a truly quiet environment.

It could be, then, that some of the physical and emotional problems you may be experiencing actually are symptoms caused by your level of noise-induced autonomic arousal. That would be consistent with the perspective of researchers who concluded that noise may be harming you even if you are not aware of being bothered by it.

However, to be sure, being a bit tense and a trifle irritated by noise is not at all the same as being traumatized by it. Rather, noise-induced trauma can be said to occur when noise exposure causes such severe distress or injury over time that some significant degree of social, emotional, functional, or physical debilitation sets in.

Whether you are deeply traumatized by noise or injured at some lesser level, or whether you are simply irritated by its presence depends on several factors. For one thing, the severity of the injury you suffer when exposed to a given noise depends to an enormous extent on the level of toxicity associated with that particular sound. For example, if the sound of water falling in your neighbor's outdoor fountain is force-fed into your bedroom, that would almost certainly produce less of a response from your autonomic nervous system and, therefore, have less potential for producing injury than if the guy next door were to chain a barking dog in that exact same spot.

If you doubt that some sounds are more toxic than others, check-out the research done in the United Kingdom by the University of Salford, where they tested people's reactions to thirty-five different sounds, commonly thought to be grating, in an effort to determine which sounds human beings find the most aversive.

Obviously, the decibel level to which any given individual is exposed is also going to make a huge difference, with the louder and sharper sounds more readily shooting the autonomic nervous system into the upper tiers of high-arousal functioning.

How often you are bombarded with noise is critically important as well, because if there are long stretches of time in-between outbursts of unwanted sound, and there are no other stressors in your life to ratchet-up your ANS, then, the long periods of silence between outbursts will allow your autonomic processes to slow down and let you recover somewhat before some new stressor once again elevates your level of autonomic functioning.

Long breaks between outbursts of noise give the autonomic nervous system the time it needs to return to baseline with a regularity that is sufficient to maintain homeostasis. Therefore, the more widely spaced the noise, the less traumatic it is likely to be.

Remember, having a high level of autonomic arousal is not necessarily a bad thing. Indeed, it only becomes a health hazard when the high level of autonomic functioning becomes by far the dominant mode and remains so over time, because in that circumstance the physical body begins to break down under the all-too-frequent strain, as does the psyche, which often lays waste to family and social relationships along the way.

When the noise occurs is also critically important. Even a little noise can be extremely detrimental if it is projected into your home during the very limited time that you might have otherwise slept or relaxed, because sleep and recuperative relaxation are not luxuries. Rather, they are essential to the effective functioning of the autonomic nervous system and the maintenance of good health.

What the noise costs you and how much you suffer from it will definitely factor in to the question of to what extent exposure to a given level of noise is likely to traumatize any given individual. For example, if noise from the neighbor's place keeps you from sitting outside in your hot tub, that is sure to be less upsetting than if noise force-fed into your bedroom throughout the night compels you to get up and go to work the next day with only two or three hours of sleep.

The general rule is that the more noise interferes with your ability to meet your needs, the more traumatic your exposure will be, with your ability to fulfill your basic needs of rest, relaxation, and sleep, being more critical variables than your capacity to satisfy your more subtle requirements.

How much stress the subject is under to begin with is another critical factor. Some people are constantly on edge from a wide-ranging array of irritants that have their autonomic systems already running on overtime as they attempt to cope with multiple stressors that all but overwhelm them, even in the best of times. For those who are so severely lacking in resilience, just a little noise forcibly projected into their last refuge can quickly bring them to the breaking point. Therefore, to a large extent, the condition you were in before you were forcibly exposed to noise will also figure-in, with people who were already under stress, in ill-health and/or living on the margin at the outset, sure to be impacted more readily.

Written by Craig Mixon, Ed.D. - Barking Dogs Webmaster

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This page on Noise Trauma is part of Section Seven:
the Harm section of