Tinnitus is caused by changes in how your brain processes sound, usually triggered by some form of damage or disruption to the auditory system. About 14.4% of adults worldwide have experienced it, with nearly 10% dealing with a chronic form lasting longer than three months. The ringing, buzzing, or whooshing you hear isn’t coming from an external source. It’s generated internally, and the triggers range from noise exposure and medication side effects to blood vessel abnormalities and jaw problems.
How the Brain Creates Phantom Sound
Most tinnitus starts with reduced input from the ear to the brain. When hair cells in the inner ear are damaged, whether from loud noise, aging, or disease, fewer sound signals reach the auditory centers of the brain. In response, the brain compensates by turning up its own activity, essentially amplifying neural noise to fill the gap. This compensation is what you perceive as ringing or buzzing.
Brain imaging studies show increased activity in the auditory cortex and thalamus of people with tinnitus, particularly in high-frequency neural oscillations called gamma waves. What appears to happen is that slower-than-normal brain waves develop in the damaged frequency region, and the contrast between these sluggish zones and the surrounding healthy tissue creates a kind of imbalance. The neighboring neurons become overactive, producing the phantom sound. This is why tinnitus often matches the pitch of the frequencies you’ve lost hearing in.
This also explains why tinnitus is so persistent. Once the brain rewires itself to compensate for lost input, the pattern can become self-sustaining even if the original trigger is resolved.
Noise Exposure and Hearing Loss
The single most common cause of tinnitus is damage to the sensory cells in the inner ear, called hair cells. These cells convert sound vibrations into electrical signals for the brain, and they don’t regenerate once destroyed. Loud noise, whether from a single blast or years of occupational exposure, can kill outer hair cells, damage the connections between inner hair cells and the auditory nerve, or physically rupture delicate structures in the cochlea. All of these reduce the signal the ear sends to the brain, setting off the compensation cycle described above.
Age-related hearing loss works through a similar mechanism. As hair cells gradually deteriorate over decades, the brain receives less and less input at higher frequencies. This is why tinnitus becomes more common with age and why many people describe it as a high-pitched tone.
Earwax, Infections, and Pressure Problems
Not every cause of tinnitus involves permanent damage. Anything that blocks or alters sound reaching the inner ear can trigger it. Earwax impaction is one of the simplest and most reversible causes. When cerumen builds up enough to obstruct the ear canal, it changes the sound input reaching your auditory system, and the brain may respond by generating tinnitus. Removing the blockage often resolves it.
Middle ear infections can do the same thing by filling the space behind the eardrum with fluid, dampening sound transmission. Eustachian tube dysfunction, where the small tube connecting your middle ear to the back of your throat doesn’t open and close properly, creates pressure imbalances that alter how sound travels. This is why you might notice tinnitus during a bad cold, with severe allergies, or after flying. Otosclerosis, a condition where abnormal bone growth stiffens the tiny bones of the middle ear, is another mechanical cause.
Medications That Affect Hearing
Certain medications are known to be ototoxic, meaning they can damage the ear and trigger tinnitus. According to Harvard Health Publishing, the most common culprits include high-dose aspirin, macrolide antibiotics like azithromycin when used at high doses for extended periods, certain chemotherapy drugs (particularly platinum-based ones), and loop diuretics used for heart failure and kidney disease. Some newer biologic drugs used in immunotherapy and disease modification can also affect hearing.
In many cases, tinnitus from medications is dose-dependent and reversible once the drug is stopped or the dose is lowered. But with some chemotherapy agents, the damage can be permanent. If you notice new ringing after starting a medication, that’s worth bringing up with whoever prescribed it.
Meniere’s Disease and Inner Ear Disorders
Meniere’s disease causes episodes of intense vertigo, fluctuating hearing loss, tinnitus, and a feeling of pressure or fullness in the affected ear. The underlying problem is an excessive buildup of fluid in the inner ear’s membranous labyrinth, a condition called endolymphatic hydrops. Why this fluid accumulates isn’t fully understood, but genetics, autoimmune responses, infections, allergies, and trauma have all been implicated. The tinnitus in Meniere’s disease tends to fluctuate along with the other symptoms, often worsening before or during a vertigo attack.
Jaw and Neck Problems
Tinnitus doesn’t always originate in the ear. Problems in the jaw joint (TMJ disorders) and the upper cervical spine can produce what’s known as somatic tinnitus. This happens because nerves from the jaw and upper neck feed into the same brainstem structures that process sound, specifically a region called the dorsal cochlear nucleus. When these nerves send abnormal signals due to muscle tension, joint dysfunction, or injury, they can interfere with auditory processing and create or worsen tinnitus.
A hallmark of somatic tinnitus is that you can change its pitch or volume by clenching your jaw, turning your head, or pressing on certain neck muscles. The nerve roots of the second, seventh, and eighth cervical vertebrae, along with the trigeminal nerve that supplies the jaw, all have documented connections to auditory pathways in the brainstem. This type of tinnitus sometimes improves with physical therapy, dental treatment, or correction of posture and alignment issues.
Pulsatile Tinnitus: A Different Category
If the sound you hear pulses in rhythm with your heartbeat, you likely have pulsatile tinnitus, which has entirely different causes from the more common ringing type. Pulsatile tinnitus is generated by actual blood flow, and it’s one of the rare forms that a doctor can sometimes hear too (making it “objective” tinnitus, as opposed to the “subjective” type only you can detect).
The sound comes from turbulent blood flow in vessels near the ear. This turbulence can result from narrowing (stenosis), abnormal connections between arteries and veins, or unusual anatomy. On the venous side, common causes include increased pressure inside the skull from a condition called idiopathic intracranial hypertension, narrowing of the large veins behind the ear (transverse sinus stenosis), and abnormalities of the jugular vein where it sits close to the inner ear. On the arterial side, carotid artery narrowing from atherosclerosis is the most frequent cause in older adults, affecting 8 to 20% of the general population. Arterial dissections, where the wall of a blood vessel tears, and a condition called fibromuscular dysplasia, which mainly affects women between 20 and 60, can also cause it.
Pulsatile tinnitus always warrants medical evaluation because some of its causes, like arteriovenous fistulas or aneurysms, need treatment.
How Stress Amplifies Tinnitus
Stress doesn’t typically cause tinnitus from scratch, but it reliably makes existing tinnitus worse. The body’s main stress response system, the HPA axis, is commonly disrupted in tinnitus patients. When you’re stressed, your body releases cortisol and norepinephrine. These hormones act on the limbic system, particularly the amygdala, hippocampus, and prefrontal cortex, all of which are brain regions implicated in tinnitus perception.
Research on veterans with PTSD found that tinnitus loudness increased during periods of high stress. In laboratory studies, tinnitus patients with high baseline stress levels showed elevated cortisol after social stress tasks, along with subjective increases in both stress and tinnitus severity. This creates a feedback loop: tinnitus causes anxiety, anxiety raises stress hormones, and those hormones make the tinnitus louder and more intrusive. Emotional stress is now considered one of the most important predictors of how severely someone experiences their tinnitus, independent of the volume of the sound itself.
The same brain regions involved in anxiety and depression overlap significantly with those involved in tinnitus. Chronically elevated cortisol levels influence the amygdala in ways that are common to all three conditions, which is why tinnitus, anxiety, and depression so frequently occur together.