Noise sensitivity is a problem when it prevents a person from living a normal life. Physical or psychological health conditions often affect the way we hear noise and sound. Medical conditions of sound and noise include tinnitus, hyperacusis, misophonia, phonophobia, recruitment, and vibroacoustic disease.
Everyone is sensitive to certain sounds. Fingernails on a blackboard make most of us cringe. Loud sounds such as amplified music or the sound of power tools can cause hearing damage, deafness or increased sensitivity to noise. Prolonged exposure to sounds such as industrial or computer noise can also trigger noise sensitivity.
Medical conditions of sound and noise include tinnitus, hyperacusis, misophonia, phonophobia, recruitment, and vibroacoustic disease.
Effects and Causes of Noise Sensitivity
Sensitivity to noise isn’t always related to the loudness, or decibel level, of a sound. For example, a person with noise sensitivity might think that the ticking of a watch (20 decibels) is louder than the hum of a dial tone (80 decibels).
A noise-sensitive person has difficulty leading a normal life. Noise sensitivity causes anxiety, reclusive behavior, depression, hypertension, sudden rages, and the feeling of going crazy. The sufferer may hear a sound as overwhelming, even though others may not notice it at all.
A person who is noise sensitive can experience headaches and other physical ailments. In extreme cases, a person may attempt suicide or lash out at others, in a desperate attempt to stop the noise.
Causes of noise sensitivity may include unpleasant associations with a sound; prolonged exposure to loud or abrasive sounds; ear or sinus infection; damage to the inner ear structure; or progressive hearing loss. Lack of magnesium in the diet is another possible cause. Noise sensitivity may be a symptom of TMJ disorder. Stress or fatigue can aggravate a sensitivity to noise. See also: TMJ Disorder and Noise Sensitivity.
How much noise is too much noise?
Decibels (dB) measure the volume, or loudness, of a sound. Suffers of noise sensitivity will perceive certain sounds as distorted, or louder than they really are. The normal human ear can safely withstand 85 decibels for about eight hours, or 100 decibels for about fifteen minutes.
A soft whisper: 30 dB
Rainfall: 50 dB
Normal conversation: 60 to 70 dB
A screaming child: 90-110 dB
A power mower: 107 dB
Music at a rock concert, within four to six feet of the speakers: 120-140 dB
A jet engine: 140 dB
Medical Conditions of Noise and Sound
Symptoms of tinnitus include ringing, buzzing or other unpleasant noise in the ears. Some people hear beeps and whistles. Tinnitus affects about 17% of the population. The causes are uncertain, and tests are usually necessary to determine whether or not the condition is physical. Stress and fatigue are known to aggravate tinnitus.
Victims of hyperacusis hear all sounds too loudly. Severe hyperacusis is rare, but many people suffer from a milder form. 40% of tinnitus patients also have hyperacusis. Musicians, who play in a loud environment, or people exposed to prolonged industrial or workplace noise, can develop mild hyperacusis as well.
Misophonia is an intolerance to certain sounds, such as food being chewed. Literally, misophonia means “dis-like of sound”. A person suffering from misphonia will have strong emotional reactions to certain sounds.
Phonophobia, or fear of sound, often occurs together with misophonia or other conditions. Despite the term, the sufferer doesn’t always feel afraid of a sound, but the sound triggers an unconscious physical response. The body tenses, breathing gets shallow, and the mind becomes highly focused on the sound. The sufferer may become obsessed with the sound, even when it’s not present.
Recruitment is usually a side effect of hearing loss. Sufferers may have trouble hearing sounds below 50 dB, but sounds over 80 dB seem amplified or distorted. Recruitment is often due to changes or damage to tiny hairs in the inner ear. Damage or changes to the hairs can cause distortion or erratic transmission of sound.
6. Vibroacoustic Disease
This condition usually occurs over several years of exposure to a low-frequency sound such as that of machinery. Often, the sound is too low for the human ear to detect. Symptoms cover a wide range of physical and psychological ailments, and may include aggressive or abnormal behavior, vertigo, visual impairment, stroke, and neurological conditions such as epilepsy.
Diseases of noise and sound are real and often disabling. Usually one condition occurs together with other physical or psychological conditions, making diagnosis and treatment difficult. Medical science is only beginning to understand the effects of noise and sound on an individual.