Effects of Loud Sound on Human ear

How do we hear?

The overall structure of the human ear can be divided into three broad parts:

• The outer ear

• The middle ear

• The inner ear

The sound waves enter the ear through the outer ear and reach the eardrum. Due to these sound waves, the eardrum vibrates and sends the vibrations to the three bones present in the middle ear. These bones then increase the volume of the sound vibration and then forward it to the inner ear. The inner ear contains two critical structures that play a significant role in how you hear:

• Cochlea is a fluid-filled structure present inside the inner ear

• Tiny hair cells which act as receptors for detecting sound

The amplified sound waves create vibrations in the fluid which causes tiny hair cells to bend and convert the vibrations into electrical signals

Once the sound waves are converted into electrical signals, the auditory nerve carries these signals to the brain, which interprets the sound.

Note: Auditory nerve is a bundle of nerve fibers.

What is defined as loud sounds?

Studies have shown that sound levels above 85 dBA can damage your ear

Note: Decibels (db) is the unit used to measure the loudness of a sound. However, since human hearing cannot hear all sound frequencies therefore based on the hearing threshold of human beings the unit dBA (A-weighted decibels) is used

How do you know which sounds are safe for you?

Based on the table below containing familiar sources of sound and their levels, you can get an idea about which sounds are safe for you and which are not. It would be best if you tried to limit your exposure to the sounds that are above the harmful threshold

What are the effects of loud sounds on the human ear?

Exposure to loud sounds can damage the hair cells in the human ear, causing noise-induced hearing loss (NIHL). The hair cells in the human ears don’t regenerate. Therefore after prolong or consistent exposure to loud noises, if the hair cells die, they won’t grow back, and you will suffer from hearing loss.

What are the symptoms of noise-induced hearing loss?

Typically, noise-induced hearing loss is gradual. However, if you notice the following signs and symptoms, you may be losing your hearing because of exposure to high volumes of sound:

• With time sound becomes distorted or muffled

• Difficulty in listening during a conversation

• Consistently needing to increase the volume of televisions because of the inability to hear at normal levels

• Requiring hearing aids to listen to the sounds around you

• Ringing or buzzing sound in the ear – tinnitus

Sometimes noise-induced hearing loss can be temporary, and your hearing can return within 16 to 48 hours. However, studies have shown that even though the hearing returns, there is a long term hearing damage.

Alert: Since the loss of hearing is gradual, you may not notice it until it’s too late. Hence, if you notice the slightest of symptoms like needing to raise the volume of your radio or stereo because you are not able to hear at lower volumes, you should get yourself tested. If the hearing loss is detected in the early stages, its progress can be managed. However, if overlooked, it can severely impact your life.

How is noise-induced hearing loss diagnosed?

For the diagnosis of noise-induced hearing loss, your health care provider will adopt the following approach:

• Routine evaluation

• Audiometry: this test is conducted to evaluate your ability to listen to sounds at varying levels of accurately

• Sound intensity
• Pitch
• Tones
• The audiometry test involves different thresholds and frequencies.

Note: Typically NIHL is caused because of high-frequency sounds

Are there treatments available for noise-induced hearing loss?

Noise-induced hearing loss is permanent; however, if detected at the right time, your doctor may recommend the following steps to stop further damage and to manage your loss of hearing better:

• Cochlear implants: These are surgically implanted electronic devices that modify your sense of sound. Cochlear implants send an electrical signal to simulate the auditory nerve directly. Therefore due to the cochlear implants, your normal process of the hearing will be bypassed.

• Hearing aid: These are recommended to magnify the sound

• Suggestions to avoid further exposure to loud noises after diagnosis what kind of sounds damaged your ear in the first place

Can you prevent Noise-induced hearing loss (NIHL)?

With some proactive measures, you can save your hearing and avoid the harmful effects of loud sound on your ears:

• Use hearing protection devices like activity-specific earplugs or earmuffs to save your ear if you are always in a situation where there are loud noises

• Be wary of the loud noises primarily if you work in a hazardous environment where this is the situation, for example, a factory or a nightclub

• Learn about the noises that are harmful to your ears and try to avoid them

• Keep the volume low when listening through headphones and Bluetooth devices

• Get yourself tested if you suspect hearing loss

• Keep your children away from loud music or equipment at home

Finally, can Noise-induced hearing loss be cured permanently?

Unfortunately, so far, there is no way to reverse the harmful effects of loud sounds on the human ear and to cure NIHL permanently.

However, if diagnosed at the right time, it can be managed better.

References:

1. https://www.ncbi.nlm.nih.gov/-pmc/articles/PMC4356173/
2. https://www.ncbi.nlm.nih.gov/-pmc/articles/PMC4311346/
3. https://www.ncbi.nlm.nih.gov/-pmc/articles/PMC6513655/
4. https://www.cdc.gov/nceh/hearing-_loss/what_noises_cause_hearing_loss.html