In about 90% of cases, tinnitus is a phantom sound produced by the brain. That is, the sounds don’t come from the external environment; they are not real physical sounds.
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This type of tinnitus is also called subjective tinnitus, because the sound is only heard by the person who suffers from it, and cannot be detected by external means.
Having said that, there are likewise external issues that can cause tinnitus, but they cause fewer than 10% of cases. For instance, physical blockages outside the inner ear, such as the accumulation of earwax or fluid build-up from a middle ear infection may force the brain to “turn up its internal volume.”
In addition, the sounds may be produced by an actual internal physical movement or fluid flow, which can be heard by a third person by using a stethoscope near the ear or jaw. For instance, vascular issues, such as high blood pressure, changes in blood flow, or narrowed arteries near the ear, or uncontrolled muscle spasms in the tiny muscles of the middle ear or jaw can cause tinnitus. This type of tinnitus is known as objective tinnitus.
In any case, the brain creates the inner sound(s) of tinnitus in two main situations:
The first situation is when it’s trying to compensate for the loss of real sound input. This happens when the small hair cells in the inner ear are damaged or aged, and they have stopped sending normal sound signals to the brain. In response to this hearing loss, the brain simply turns up its internal volume to listen closer. This higher neural sensitivity amplifies its own background electrical noise (internal static), which the brain then mistakenly interprets as a real, continuous external sound such as ringing, buzzing, roaring, clicking, or hissing.
The second situation is that of somatic tinnitus. In this case, the brain creates the sound(s) because it confuses physical touch and/movement signals with sound signals.
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For instance, if you have head, neck or jaw tension, a neck injury, or bad posture, the nerves in the head, neck or jaw start transmitting chaotic physical distress signals to the brain. Because these nerves are positioned right next to the auditory nerves in a central pathway when traveling to the brain, these intense physical signals may “spill over” into the auditory pathway.
The brain then, which through the auditory nerves receives these electrical signals from the neck or jaw nerves, translates those into high-pitched ringing, hissing, or buzzing because the auditory center only knows how to process sound.
Now, clenching the jaw or pressing on it, opening the mouth, turning the neck, or pushing on your head physically alters the electrical current flowing through the accompanying nerves and hence instantly change the volume or pitch of tinnitus. This, by the way, is one of the most clear signs that you suffer from somatic tinnitus, and one of the primary methods healthcare professionals use to diagnose the type of tinnitus you have.
Keep in mind that somatic tinnitus quite often has an emotional root cause, that is, sustained and accumulated stress and anxiety, or a sudden traumatic experience, typically leads to tension of the head, neck, jaw, and shoulder muscles, jaw clenching, and/or hypersensitivity of the trigeminal nerve system, which create or increase the phantom sounds.
