Researchers say they were left shocked after a man being treated for severe obsessive-compulsive disorder became a passionate Johnny Cash fan after having a stimulation device planted in his head.

A report in the Frontier in Behavioral Neuroscience journal by Mariska Mantione and colleagues describe the case of “Mr. B.”, a 58-year-old Dutch man who had suffered severe obsessive-compulsive disorder from the age of 13.

As a last resort he was given deep brain stimulation (DBS), a surgical treatment involving the implantation of a medical device called a brain pacemaker, which sends electrical impulses to specific parts of the brain.

The treatment worked, the researchers said, as his anxiety and symptoms went down.

“Mr. B. reported he felt very confident, calm and assertive and he started to call himself 'Mr. B. II', the new and improved version of himself,” they said in the paper.

However, there was one unusual side-effect. Mr. B.’s brain couldn’t get enough of Johnny Cash.

“Half year after DBS surgery, Mr. B. stated that he was turning into a Johnny Cash fan. He had been listening to the radio, when he coincidentally heard Ring of Fire of the country and western singer and experienced that he was deeply affected by the song. Mr. B. started to listen to more songs of Johnny Cash and noticed that he was deeply moved by the raw and low-pitched voice of the singer,” researchers wrote. “Mr. B. reported that he felt good following treatment with DBS and that the songs of Johnny Cash made him feel even better. From this moment on, Mr. B. kept listening simply and solely to Johnny Cash and bought all his CD’s and DVD’s … From the first time Mr. B. heard a Johnny Cash song, [all other music] has been banned.”

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