Tinnitus is a disturbing sound that may be perceived in one or both ears, or inside the head. It is most commonly described as a high-pitched “ringing,” but it may also be experienced as buzzing. In some cases, tinnitus presents as a variable, diffuse sound across the entire audible frequency range (such as chirping, cicadas, crickets, squeaking, or frying noises), or as a pulsating sound like a heartbeat, or intermittent like a mechanical clicking.

As for intensity—that is, the loudness of tinnitus—although it can be measured through audiometric tinnitus tests, its subjective impact is of primary importance, namely the level of distress it causes to the individual. Tinnitus that is classified as mild in intensity based on audiometric testing may be perceived by the patient as unbearable and can lead to a complete inability to carry out normal daily activities.

Tinnitus cannot be defined as a specific disease; rather, it may represent a symptom of various conditions, not necessarily affecting the ear or the auditory pathways. However, it has been shown that, in virtually all cases, tinnitus is associated with some degree—often very slight—of inner ear damage. Tinnitus is generally subjective, meaning it can only be perceived by the person affected. Only in very rare cases is it objective, that is, audible to an external examiner.

Objective tinnitus is generated by mechanical movement within the skull or the cervico-facial region. Examples include small clonic contractions of certain muscles or noise produced by blood flow within the arteries. Subjective tinnitus, on the other hand, originates within the auditory pathways or the brain and is a “phantom” sound, audible only to the person who experiences it.

Causes of Tinnitus and Hyperacusis

Conscious sound perception originates in the cerebral cortex, meaning that we hear with our brain. Sounds reach the cerebral cortex in the form of nerve impulses coming from the ear through the auditory pathways, which consist of the auditory nerve and its processing centers (subcortical nuclei).

Within the ear, it is the cochlea that converts the sound vibrations transmitted by the eardrum into nerve impulses, which then travel through the auditory nerve to the brain. The cochlea is made up of thousands of nerve cells (hair cells), characterized by tiny cilia on their surface that are sensitive to sound vibrations. These hair cells are directly connected to the auditory nerve. As it exits the cochlea, the auditory nerve consists of approximately 30,000 fibers. In fact, the auditory nerve does not merely transmit sounds to the brain; through the subcortical nuclei, it also processes them.

The auditory nerve functions bidirectionally: it carries sound signals from the periphery (the ear) to the center (the auditory areas of the brain), and it also sends regulatory and control signals from the center (the brain and neural nuclei) back to the periphery. This mechanism plays a crucial role in enhancing the perception of voices and sounds.

To further refine sound processing, the auditory system operates in a “cross-modal” manner, meaning it interacts and exchanges information with other sensory systems and with motor centers.

How Tinnitus Develops

Even a small functional change in a neural center can have consequences—at least temporarily—along the entire auditory pathway.

Likewise, a dysfunction affecting a limited area of the ear’s hair cells can create an imbalance that develops into tinnitus. The site that most often “triggers” tinnitus is the cochlea, where even mild and transient stress can lead to a small lesion. Although this lesion often has no noticeable effect on hearing sensitivity and may only be detected through advanced audiometric techniques, it can cause an imbalance in neural nuclei and thereby lead to the onset of tinnitus.

Tinnitus may be caused by common ear conditions such as viral or bacterial infections, otitis, otosclerosis, tympanosclerosis, genetic hearing loss, and others. Other minor dysfunctions—such as problems involving the cervical spine or temporomandibular joint, posture-related issues, middle ear disorders, or dental problems—can also affect the auditory system, creating imbalances that may induce tinnitus.

Certain medications, known as “ototoxic” drugs, can have side effects on the ear. In addition, the body itself can produce substances that become harmful to the ear under conditions of acoustic stress or more general psychophysical stress; this phenomenon is known as “excitotoxicity.” Clinical experience shows that tinnitus frequently begins during or following periods of anxiety, stress, or intense emotional experiences. Furthermore, the ear may be affected by autoimmune conditions, which can sometimes manifest with tinnitus as well.

Tinnitus: a multifactorial condition

The entire body plays a crucial role in the onset of tinnitus. The causes can be multiple, which is why tinnitus is defined as a multifactorial condition. Moreover, these causes vary from patient to patient. This is why there is no single, universal cure that is effective for everyone. Problems involving the cervical spine or temporomandibular joint, postural issues, dental problems, hormonal imbalances, organic dysfunctions even at an early stage (e.g. circulatory problems, diabetes, etc.), increased anxiety, unhealthy lifestyles, and poor dietary habits can all create imbalances in the body that favor the onset of tinnitus.

The primary role of the brain

While the tinnitus sound is generated by an imbalance in the auditory pathways in combination with the dysfunctions described above, its persistence is “sustained” by the brain. Higher neural centers develop selective attention toward this sound and can even self-generate it, making it “audible” even after the original triggering cause has been resolved. Fortunately, the auditory system and the brain—like the rest of the body—have a strong ability to restore balance, thanks to brain plasticity.

A simple example: why do we “feel” a new watch on our wrist only during the first few days or hours after wearing it? Because the brain learns to consider that tactile sensation as normal and eventually “forgets” it. In a similar way, it is possible to “reprogram” the auditory pathways both to habituate to tinnitus until it is no longer noticed and, through external stimulation, to promote adaptive responses by harnessing brain plasticity, which remains active at any age.

Tinnitus as a conditioned response

When a sound has a special meaning, such as an ambulance siren or hearing our name being called, we respond to these auditory stimuli automatically. This occurs after a brief learning period, but these automatic responses remain active throughout life. Even faint sounds, if they are meaningful to the listener, are detected by neural centers between the ear and the auditory cortex and are sent to the brain as a signal of danger.

These conditioned responses are filtered by the limbic system, a very important part of the brain that links sensory perceptions to emotions. In turn, the limbic system controls the autonomic nervous system, which unconsciously regulates bodily functions.

What happens, even in cases of mild but persistent tinnitus, is the activation of a conditioned response to the sound. Since this response occurs in an unconscious part of the brain, what the patient consciously thinks about tinnitus has little influence on the reaction it produces.

The physiological reaction triggered by tinnitus through the limbic system and the autonomic nervous system is fundamental in creating a continuous state of agitation and discomfort. Stress is therefore determined by the degree to which unpleasant sensations related to tinnitus (from limbic system activity) and tension (from autonomic nervous system activity preparing the body for reaction) are experienced by the individual. External stress caused by fatigue, work, or other physical disorders, as well as a predisposition to anxiety, further amplifies the discomfort and annoyance associated with tinnitus.

Tinnitus = threat

When tinnitus is first perceived, it represents a new signal: there are no existing auditory memory models and no way to categorize it. Any new auditory experience tends to produce discomfort due to the loss of a state of well-being and the change in habitual auditory conditions. Until an appropriate evaluation of the meaning of tinnitus is made, this symptom is viewed with suspicion and fear. Many people with tinnitus do not describe it as a severe disorder, yet because of the tinnitus = threat association, they live in a state of significant distress.

Many patients consider tinnitus a serious symptom, often fearing it is a warning sign of a hidden, severe disease or that it represents permanent damage to the ear. There is also a common fear that tinnitus will continue forever, disturbing peace and quiet and preventing concentration at work, leisure activities, and sleep.

In some patients, extreme fear of tinnitus leads to the development of a phobic state similar to fear of spiders, snakes, confined spaces, and other phobias.

Fears related to tinnitus may be amplified by negative experiences shared by acquaintances or by incorrect advice from unqualified professionals. However, it is important to know that today effective, research-supported therapeutic approaches exist to manage tinnitus and significantly improve quality of life. A positive and reassuring message from qualified professionals, combined with a personalized treatment plan, can make a substantial difference. Even patients who have experienced ineffective treatments in the past may find relief by relying on appropriate therapeutic pathways and specialized care.

Hearing loss and tinnitus

Hearing loss can increase the perception of tinnitus. The loss may be mild or limited only to high frequencies. Anything that stresses the auditory system (such as a simple ear infection or temporary hearing loss due to a severe cold) can increase the imbalance of the neural pathways involved in tinnitus generation and consequently intensify its perception. For this reason, correcting hearing loss with appropriate hearing devices is an important part of tinnitus therapy.

Conclusion

It is therefore essential to understand the role of the inner ear as the “triggering” cause of tinnitus, the importance of factors such as anxiety, skeletal and muscular issues, and dysfunctions that may seem far removed from the ear as “accelerators” of the disorder, and the role of the brain, which is responsible for the persistence of tinnitus, our emotional responses to it, and therefore the distress it causes.

A qualified specialist consultation is the first fundamental step in addressing tinnitus. During this evaluation, an expert can identify possible causes, assess the severity of the condition, and detect associated factors such as musculoskeletal, organic, or neurological issues.

This process allows for the development of a personalized therapeutic plan, significantly increasing the chances of symptom relief and improvement in quality of life. Turning to experienced professionals ensures a multidisciplinary, up-to-date approach, which is essential when managing a complex condition such as tinnitus.