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Q: I can't stand the continuous ringing of bells during prayer in my house. Is there something wrong with me? These sounds irritate me a lot. Why is this?
Krishna: Some people have a higher sensitivity to sound than others. While the majority of people respond negatively to excessively loud sounds or very sharp sounds, others find everyday sounds overwhelming too. People who experience ear ringing or tinnitus may also have hypersensitive hearing.

People with normal hearing function will typically find very loud noises uncomfortable. Noises within a frequency range of 2,000 to 5,000 Hz are known to be particularly difficult to listen to. There are two reasons for this.

Firstly, our hearing function is damaged when we are exposed to loud noises. In fact, anything over 85 decibels could cause hearing loss. As loud sounds damage the nerves, membranes and hair cells within the ears, it’s logical that we experience these sounds as unpleasant noise. As we find these noises so uncomfortable to listen to, we are more likely to switch to a different environment or lower the volume, thus protecting our hearing function from exposure to the loud sounds.

Secondly, studies have shown that our brains respond differently to high pitched sounds, particularly those within a 2,000 to 5,000 Hz frequency range. Although it’s not entirely understood why this happens, imaging studies have confirmed that a particular part of the brain, the amygdala, becomes active when we hear noises at this level. As the amygdala is responsible for our emotional reactions, it may explain why these high-pitched noises cause us to experience a sense of discomfort, fear or even panic.

There is  a condition called hyperacusis, where ordinary sounds seem uncomfortably loud. But researchers are just starting to understand that some patients experience a more severe form, where noise is not just heard — but is actually felt, as physical pain. Using new lab tools and techniques, pioneering scientists have identified what appear to be pain fibers in the inner ear, or cochlea. They are coining new terms, including “noxacusis” and “auditory nociception,” for this newly recognized sensation of noise-induced ear pain. In cases of hyperacusis, however, the individual’s ability to tolerate noise is lowered. Essentially, their Loudness Discomfort Levels (LDL’s) are much lower than average.

Hyperacusis can be associated with auto-immune disorders, traumatic brain injury, metabolic disorders, and other conditions.

The hearing and balance systems of the inner ear are interconnected. Both systems are filled with fluid whose movement stimulates tiny sensory cells. Sounds are detected as energy vibrations; the human cochlea can hear best the frequencies associated with speech. The balance system uses lower-frequency sensations to help maintain posture in relation to gravity.

Hyperacusis is an abnormal condition in which the complex electrical signals generated by sound vibrations are misinterpreted, confused, or exaggerated. The signals coming in are identical to those that present to a normal ear, but the reaction in the abnormal system is markedly different: for example, the sounds in a quiet library may seem like a loud parade to a person with hyperacusis.

Exposure over time to more modest noise — from music, movies, sirens, lawnmowers, and a thousand other everyday things — can damage hearing and set off the pain fibers. Noise can cause damage even if it doesn’t feel uncomfortably loud in the moment. Individual susceptibility to noise exposure varies greatly, and may be genetic. There’s no firm estimate of how many people may suffer from noise injury.

COCHLEAR VS. VESTIBULAR HYPERACUSIS

With cochlear hyperacusis, subjects feel ear pain, discomfort, annoyance, and irritation when certain sounds are heard, including those that are very soft or high-pitched. Most people react by covering their ears or leaving the room. Severe emotional reactions may also occur; crying or panic reactions are not uncommon.

In vestibular hyperacusis, exposure to sound can result in falling or a loss of balance or postural control. Such disturbances have been called by various names, including Tullio’s syndrome and audiogenic seizure disorder. Some of the same reactions as with cochlear hyperacusis can also occur, along with sudden severe vertigo or nausea. In some cases, vestibular hyperacusis can affect the autonomic system and cause problems such as loss of consciousness, mental confusion, nausea, or extreme fatigue.

In both cochlear and vestibular hyperacusis, headache is common. In addition, many subjects with hyperacusis feel distinct cognitive changes during these exposures and will describe themselves as being “out of myself” or disassociated from reality, unable to take in other stimuli, having an immediate feeling of something being wrong or a sensation of being unwell or experiencing severe confusion.

A suspected cause of cochlear hyperacusis involves a loss of the regulatory function provided by the system that conducts impulses along the auditory neural pathways. In hyperacusis, the mechanism that regulates amplification erroneously magnifies the incoming sounds and noises instead of reducing them. For example, the sound of a passing car is interpreted as comparable to the roar of a jet engine!

Other possible explanations of cochlear hyperacusis involve brain-chemistry dysfunction or head trauma that damages the chain of tiny bones in the middle ear that amplify sound and help transmit vibrations to the inner ear fluid. Changes in the transmission of electrical signals along complex neural pathways are also highly possible in cases of head injury.

In vestibular hyperacusis, we suspect that the main pathology results from damage to the nerve cells in the balance system. These cells may suffer damage from trauma such as head injury, metabolic disruptions due to chemical ingestions (e.g., medications or anesthesia), or circulatory changes due to heart disease or artery blockages. In addition, autoimmune disease, which can be triggered by many different causes, can harm the balance organ. Head trauma in a motor vehicle accident can set off an autoimmune reaction in the inner ear that can destroy the nerve cells, often weeks or months after the initial injury.

Hyperacusis can be treated by wearing hearing aids. Hearing aids that generate pink noise act as masking devices which minimize the impact of everyday sounds and background noise. By reducing your sensitivity to sound, carefully programmed hearing aids with pink noise generators can significantly reduce the symptoms of hyperacusis.

Some people are simply born with hypersensitivity to certain sounds. Typically, individuals are only hypersensitive to sounds which are above a certain frequency, although this varies from person to person. Depending on the level of hypersensitivity, even everyday sounds and background noise can be extremely distressing.

People with autism sometimes experience hypersensitive hearing, although it can be present in isolation. 

People with misophonia have an intense dislike of sound. Unlike other sound sensitivities, misophonia isn’t limited to loud or high-pitched. In fact, soft sounds can often be the most common triggers for people with misophonia. Sound therapy is often used to treat misophonia, although some people find that masking devices and white noise can help them to cope with exposure to noise more effectively.

Sometimes migraines cause irritation towards loud sounds.

As you can see, there are numerous causes of hearing sensitivity. A specialist can evaluate which type yours belong to and suggest remedy measures.

If these bell sounds are causing lots of discomfort to you, please see an ENT doctor.

 

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