Noise Damage May Cause Hearing Loss and Tinnitus
We’ve all heard the warnings: Protect your ears! Turn that music down! Don’t throw that firecracker at your brother!
When it comes to protecting your hearing from damage from very loud noises like sirens, loud music, firearms, motorcycles, etc ... your mother was right. Exposing yourself to sounds at those intensities may cause permanent damage to your ears. This damage may manifest itself in high frequency hearing loss.
People suffering from high frequency hearing loss may only gradually notice difficulty communicating. This may seem at first to be a loss of the clarity of speech, but not the overall volume. We get our perception of volume from low frequency sounds, and in conversational speech, these bass sounds are carried in the vowels. We perceive the clarity of speech from the high frequency sounds, which are carried by the consonant sounds of speech. That means, if you do have high frequency hearing loss, your spouse may not be able to sneak up on you while talking. You will know they are there, but when they ask you to “Bring me that hat,” you may think she said “bring me that cat.” This can lead to an eventful evening.
Another danger associated with noise exposure is tinnitus. After a loud concert, you may notice a ringing or buzzing in your ears. This sound may go away shortly after you are exposed to the loud sounds, but other times it sticks around. Tinnitus is often a symptom of high frequency hearing loss.
Yes, you hear with your ears. But your ears send the information they hear to your brain in the form of electricity where it is interpreted as sound. So, you hear with your ears AND your brain.
The normal, healthy ear picks up a broad range of sounds varying in both pitch and volume: bass sounds to very high pitched squeaky sounds; very soft whispers to booming thunder. After being damaged by excessive noise, the softest high pitch sound that the ear can hear may change. That is, the ear is damaged, and its sensitivity suffers. Your brain has been receiving very soft high frequency information from your ear its whole life. When the brain stops receiving that information, it starts to overcompensate. That part of your brain begins to look extra hard for the information it once received… it wants to keep its job. The harder that part of the brain looks for auditory information in the form of electricity, the more it is turning its own sensitivity up. We call that increasing “central gain”, or turning up your brain’s volume. When your brain does this, it may interpret some things incorrectly. It may pick up other electrical information that is not soft sound high pitch sound and interpret it as such, because that’s what it knows. Therefore, you now hear a ringing, hissing or buzzing in your ear that is not actually happening in the world around you.
“Protect your ears from loud noises, you say?! I’ll do better than that! I’ll protect my ears all day every day!”
Wait! Protecting your ears from loud, potentially damaging sounds is critical. However, if you overprotect your ears, you may be doing more harm than good. Remember when your brain lost those soft inputs, it began to turn its volume up and you started hearing ringing or buzzing or whooshing? If you plug your ears for an excessive amount of time when you are NOT exposed to damaging sounds, you are intensifying this deprivation effect. Your brain will be missing out on MORE soft sounds and turn up your central gain more than it did before. This can lead to even louder perceived tinnitus. What’s more, the quieter the setting around you, the more contrast there is between your tinnitus and the environment. This makes tinnitus more noticeable, like when you walk into a quiet room or a sound treated booth.
So, protecting your ears is an art, really. Plug up your ears when there is potential for noise damage, but the other times, let yourself hear and experience the world around you. Let the hearing part of your brain get its exercise, but keep those ears safe and healthy in the process.