stonefree

From the article,

"In participants with tinnitus, this seemingly normal signal from the brainstem comes from the brain compensating for its hearing loss by boosting nerve cells’ signal-sending activity in a way that doesn’t depend on the external sounds, Schaette and McAlpine propose. It’s this heightened — and spontaneous — nerve cell activity in the brainstem that leads to the phantom tinnitus sound, they reason."

Sounds like "in the mind" to me.