Tinnitus is the perception of a sound in the ear when there is no external source. Tinnitus is not considered a disease but a symptom. It is usually a sign that something is wrong with your auditory system.
Tinnitus sounds can manifest as whistling, clicking, blowing, pulsating, buzzing, humming, or roaring. The frequency or intensity of the sound depends on its underlying cause. The pitch of the sound also varies.
In some cases, the tinnitus sound is faint and negligible. In others, it can be so intense that it disrupts daily activities. Tinnitus can affect one ear or both. Depending on the cause, it can be temporary or permanent.
Common causes of tinnitus include sudden or continuous exposure to loud sounds, earwax blockage, head trauma or injury, tumor development in the ear, autoimmune diseases of the inner ear, ototoxic medications, and ear infections.
Besides ringing in the ear, tinnitus can be accompanied by other symptoms, such as an inability to concentrate, difficulty sleeping, and inability to follow conversations, especially in crowded places.
The structure of the ear
Our ears are responsible for hearing and balance. Each ear is divided into three main parts: the outer ear, the middle ear, and the inner ear.
The outer ear
The outer ear consists of two main parts: the earlobe and the auricle. The auricle, made of skin and cartilage, is the shell-shaped part of the outer ear that directs external sound waves into the ear canal.
The ear canal transmits the sound wave to the eardrum, which vibrates when the sound reaches it. The eardrum, or tympanic membrane, is a thin membrane that separates the outer ear from the middle ear.
The middle ear
The middle ear is an air-filled cavity, located between the outer ear and the inner ear, which contains three small bones called ossicles. These three ossicles are called the anvil, stirrup, and hammer. They form a link between the eardrum and the inner ear, via the cochlea.
When the eardrum vibrates, it transmits the vibration to the ossicles. The ossicles amplify the sound and transmit the vibration to a thin membrane located between the middle ear and the inner ear, called the oval window.
The inner ear
The inner ear contains two main structures: the cochlea and the three semicircular canals.
The cochlea, responsible for hearing, is filled with fluid and also houses the organ of Corti. This contains thousands of specialized sensory hair cells.
When vibrations reach the inner ear, the fluid inside forms tiny waves. These waves cause the extensions of the hair cells, called cilia, to vibrate. The hair cells convert this vibration into signals or nerve impulses and send them to the brain, which interprets them as sounds.
The semicircular canals also contain hair cells. Unlike those in the cochlea, these cells detect movement.
When your head moves, the fluid in the semicircular canals shifts. The hair cells detect this movement, then send nerve impulses to your brain informing it about the position of the body and head relative to gravity.
This allows your body to make the necessary postural changes to maintain balance. When this function is disrupted, you may experience dizziness or loss of balance.
Types of tinnitus
Tinnitus is classified according to the type of sound perceived by patients and its cause. Here are the most common types of tinnitus:
1. Subjective tinnitus
Subjective tinnitus is the most common type of tinnitus. It is also called non-vibratory or non-auditory tinnitus. Only the patient suffering from it can hear the sound of subjective tinnitus.
Exposure to loud sounds often causes subjective tinnitus, which can lead to hearing loss. Subjective tinnitus can appear and disappear suddenly, and last from 3 to 12 months.
When the hair cells of the inner ear are damaged, tinnitus can become permanent or lead to hearing loss.
2. Objective tinnitus
Objective tinnitus, also called vibratory tinnitus or pseudo-tinnitus, is a rare type of tinnitus caused by involuntary movements, twitching, or muscle contractions.
Eustachian tube dysfunction, a neurological disease, or muscle spasms around the middle ear can cause objective tinnitus. Unlike subjective tinnitus, these real sounds can be heard by an outside observer.
In most cases, the noise in the ear disappears when the cause of the tinnitus is identified and treated.
3. Pulsatile tinnitus
Tinnitus can present as a rhythmic noise synchronized with the patient's heartbeat. A change in blood circulation in the vessels near the ear is usually responsible. It is also called synchronous pulsatile tinnitus, vascular tinnitus, or rhythmic tinnitus.
Pulsatile tinnitus often results in a loud and disturbing blowing or pulsating sound. A change in blood flow or an abnormality in the vessels closest to the ear can also cause this type of tinnitus.
4. Neurological tinnitus
The term neurological tinnitus covers two different aspects. Conditions like Meniere's disease, which primarily affect the brain's auditory functions, cause neurological tinnitus.
The phrase "neurological tinnitus" can also describe how auditory nerves react to hearing loss.
While, in objective tinnitus, the patient hears real sounds produced by cardiovascular system disturbances, in most cases of tinnitus, patients believe they hear sounds due to neurological dysfunction.
Understanding neurological tinnitus
To understand neurological tinnitus, you must first know what a neurological disorder or disease is.
A neurological disorder is a disorder that affects the brain as well as the nerves distributed throughout the body and the spinal cord. Neurological disorders are often accompanied by muscle weakness, loss of sensation, poor coordination, and paralysis.
Causes of neurological problems include genetic diseases, congenital anomalies or disorders, brain injuries, spinal cord injuries, nerve damage, degeneration, trauma, brain tumors, and malnutrition.
Neurological diseases can affect vision, cognition, movement, communication, or hearing, depending on the location of the lesion or the nerve affected. In neurological tinnitus, the part of the brain responsible for receiving sound signals is affected.
Neurological causes of tinnitus
Neurological causes of tinnitus include head trauma, multiple sclerosis, acoustic neuroma, syphilis, meningitis, whiplash, cerebellopontine angle tumors, infections such as Lyme disease, and otitis media.
Damaged hearing
In a person with normal hearing, neurological activity goes unnoticed. When your hearing is damaged or diminished, this neurological activity is "laid bare".
In case of hearing loss, the brain automatically increases the sensitivity of the auditory system to compensate: the patient then perceives neuronal activity as a sound.
Furthermore, the brain implements a filtering mechanism that easily spots tinnitus among other signals circulating along the auditory pathways. The increase in perceived intensity makes the patient more uncomfortable, leading to anxiety and stress.
Anxiety and stress can in turn worsen tinnitus; this is why doctors sometimes prescribe anxiolytics to tinnitus patients.
Meniere's disease
Disorders like Meniere's disease can cause neurological tinnitus because they affect the brain's auditory functions. When you move your head, the fluid in the inner ear (endolymph) shifts. This movement causes nerve receptors to send a signal to the brain.
In Meniere's disease, an accumulation of endolymph disrupts balance and hearing signals between the ear and the brain. One of the results is tinnitus. The volume of fluid varies due to factors such as:
Genetic predisposition
Obstruction or anatomical anomaly leading to drainage problems
An abnormal immune response
An infection
The disease usually affects only one ear, and patients are most often between 40 and 50 years old. Depending on the cause of endolymph variations, medications or lifestyle changes can improve symptoms. It is a chronic condition, but the disease often experiences periods of remission.
While doctors usually use the term "neurological tinnitus" to refer to tinnitus caused by a pathology such as Meniere's disease, they also use it to distinguish objective cardiovascular tinnitus from subjective tinnitus.
Tinnitus treatments
Depending on its cause, tinnitus can be temporary or permanent. Its duration depends on the underlying cause.
Tinnitus due to earwax blockage often disappears after its removal: the earwax only obstructed the ear canal and prevented sound from passing through, with little or no damage to the ear.
If tinnitus is due to a more serious condition, such as an autoimmune disease of the inner ear or Meniere's disease, the risk of it being permanent is higher. Without prompt medical attention, underlying conditions can permanently damage the ear structures.
Although there is no cure for tinnitus, some treatments and therapies can alleviate its clinical symptoms and allow patients to carry out their daily activities without too much discomfort.
An ENT doctor often prescribes treatment or therapy after an audiological assessment. Here are the most commonly recommended therapies:
1. Treating the underlying cause
If tinnitus is due to damage to blood vessels, treating this damage with the appropriate medication or surgery can make it disappear.
Similarly, if tinnitus is caused by an ototoxic medication, discontinuing that medication will make it disappear. The same applies to tinnitus due to earwax blockage: once the earwax is removed, the symptoms disappear.
2. Noise cancellation
Since permanent tinnitus cannot be cured, your doctor may recommend devices designed to mask the noise. These devices are called maskers or white noise machines.
Maskers are devices that produce ambient sounds or a continuous hum. This effectively helps manage neurological tinnitus, where the sound comes from the noise of background neurological activity.
White noise machines help create enough background noise to make the noise from neurological activity less noticeable.
Instead of actual sound masking devices, you can use fans, air conditioners, or humidifiers to produce white noise.
Maskers resemble hearing aids: they produce a continuous, low-intensity white noise that masks the tinnitus sound and makes it less noticeable.
3. Psychological follow-up
Given the effect of tinnitus on patients' emotional and psychological health, psychological support is often part of the recommended therapies.
This support aims to help patients change how they perceive, think about, or feel their symptoms. Tinnitus thus becomes more bearable.
The main support options for tinnitus are cognitive-behavioral therapy and tinnitus retraining therapy.
Cognitive-behavioral therapy is conducted by a qualified psychologist who teaches patients coping techniques to enable them to carry out their daily activities without difficulty.
Tinnitus Retraining Therapy (TRT) combines sound masking devices and support from a trained professional or audiologist. The patient receives a masker designed to reduce symptoms while receiving psychological support.
Beyond tinnitus, this support can help patients cope with other related problems, such as depression and anxiety.
4. Medications
Although there is no specific medication for tinnitus, certain treatments such as antidepressants and anxiolytics are often prescribed to patients. Most of them suffer from anxiety and depression.
The relationship between tinnitus and anxiety is circular: the noise of tinnitus causes anxiety, and anxiety accentuates tinnitus.
Medications that fight anxiety and depression help alleviate tinnitus symptoms by breaking this vicious circle.
Conclusion
As you now know, neurological tinnitus comes from a brain problem, not the ears. This is why you cannot treat yourself.
"There is no substitute for a comprehensive medical examination by a qualified ENT doctor when experiencing tinnitus symptoms." - Drew Sutton, MD, board-certified otolaryngologist.
Identifying the exact cause of tinnitus and prescribing the appropriate treatment is the job of an audiologist or healthcare professional. It is important to always consult your doctor when you hear whistling or other noises in your ear.
Sources:
Tinnitus | NHS
Tinnitus: Characteristics, Causes, Mechanisms, and Treatments | NCBI
Tinnitus Treatment Options | ATA
