Tinnitus refers to a sound heard by a person that is not present in the environment around them. Lots of people get tinnitus, but it affects some people very severely. There are a number of causes of tinnitus, and a number of ways we divide it up.


The most main way we divide tinnitus up is into ‘tonal’ or ‘pulsatile’ tinnitus. ‘Tonal’ tinnitus is much more common, and refers to a continuous, often high pitched or white noise sound in the ears. ‘Pulsatile’ tinnitus refers to a whooshing sound in the ear that often occurs with the heart beating. ‘Pulsatile’ tinnitus can be ‘objective’ which means that other people can hear it, or ‘subjective’ which means other people can not hear it, even when they listen carefully. Pulsatile tinnitus needs to be investigated to rule out any concerning causes, although often these investigations do not find a specific cause.


Tonal tinnitus is often associated with hearing loss and stress (1). The brain has a system to control the amount of sound you can hear at any time. It uses this system to try and give you a constant amount of hearing, so in quiet environments you can hear quiet sounds and in loud environments you are not overwhelmed by the amount of sound you hear. When you lose hearing in one or both ears, then the amount you can hear is less than normal - it’s like you’re in a quieter environment. The brain will try to make up for that by increasing the amount of sound you can hear (2). However, if you have lost some hearing you can perceive a constant ringing sound, as there is no hearing for the brain to make louder. This is also why tinnitus is much more common in quiet environments like when you go to sleep.


The hearing loss that leads to tinnitus can be so minor that you don’t notice it and tests don’t show it, but even small amounts of wear and tear in the hearing organ (the cochlea) can cause tinnitus. The sound is most frequently high pitched, as it is high pitched hearing that is most susceptible to the wear and tear of ageing which happens from teenage years onwards.


The other system in the brain that controls how much we hear is the ‘fight or flight’ system (3). This is the same as feeling stressed. From an evolutionary perspective, this occurs because when we feel physically threatened, it is useful to be able to hear even quiet sounds clearly and loudly to have warning of nearby threats. Obviously in today’s world, we don’t feel threatened by animal attacks or things in which hearing acutely is useful, but rather by our health, family and jobs, where hearing things more loudly doesn’t really help. But the brain will still try to hear things more loudly, and this causes tinnitus.


Tonal tinnitus sometimes needs to be investigated, and hearing testing is useful. For some specific causes of tinnitus there may be medications or procedures that are recommended. Beyond that, the treatments for tinnitus focus on the two things that are the main cause of tinnitus - hearing loss and stress. For more about hearing loss see here. Stress is difficult, as tinnitus itself makes us feel stressed, which can worsen the tinnitus, which worsens the stress and so on. This cycle can be broken by something called tinnitus retraining therapy.


There is another form of tinnitus which sounds like a clicking or fluttering sound in the ears. This can be caused by spasm of muscles in the throat or the middle part of the ear. This form of tinnitus is much much less common, and there are various treatments that can be considered.


​
References:

1. A Qualitative Study on Factors Modulating Tinnitus Experience. Colagrosso EMG, Fournier P, Fitzpatrick EM, Hébert S. Ear Hear. 2019 May/Jun;40(3):636-644. 

2. The Neural Bases of Tinnitus: Lessons from Deafness and Cochlear Implants. Knipper M, van Dijk P, Schulze H, Mazurek B, Krauss P, Scheper V, Warnecke A, Schlee W, Schwabe K, Singer W, Braun C, Delano PH, Fallgatter AJ, Ehlis AC, Searchfield GD, Munk MHJ, Baguley DM, Rüttiger L. J Neurosci. 2020 Sep 16;40(38):7190-7202.

3. Personality Traits, Perceived Stress, and Tinnitus-Related Distress in Patients With Chronic Tinnitus: Support for a Vulnerability-Stress Model. Biehl R, Boecking B, Brueggemann P, Grosse R, Mazurek B. Front Psychol. 2020 Jan 24;10:3093.