We've all had an “earworm” at one time or another—a tune that gets stuck in your head and plays on an endless loop. Earworms typically fade away after a few minutes if we think about or listen to something else. But for one 54-year old woman with multiple sclerosis (MS), auditory hallucinations have plagued her non-stop for years, shedding new light on the involvement of neural pathways in MS.
In a case study published in the journal Multiple Sclerosis and Related Disorders, researchers at the Oklahoma Medical Research Foundation (OMRF) shared the bizarre story of her unrelenting internal soundtrack.
In 2010, after a long history of relapsing MS, the patient began taking the disease-modifying therapy (DMT) Tysabri. A year later, the auditory symptoms began. She hears words like “jabberwocky” several times a day, and verses of familiar country songs—complete with instrumentation—play non-stop in her head. The problem is so persistent that she has to turn on other music in order to fall asleep at night.
Some medical conditions can produce auditory hallucinations that are treatable. “We tried her on antidepressants and antiepileptic medications, but they had no effect," Dr. Farhat Husain, lead study author who now works at Integris Neurology in Oklahoma City, told Healthline,
Since earworms like this are very rare in MS, no one thought it might be a symptom of MS. “She came to me from another neurologist,” said Husain, “and by that time she had one set of MRIs but doctors were not getting anywhere. They even took her off Tysabri for a time, but it made no difference.”
Husain and her team determined that the woman didn’t suffer from any mental or emotional problems, and that she had normal hearing. So they turned their attention to her past MRI films to look for patterns of disease activity that might explain her odd hallucinations. The films revealed that since 2010 she had developed a new lesion deep within the white matter of her brain that was still present but no longer enhancing or active.
“We found the inflammation had damaged an area of the brain called the auditory association cortex, which has pathways related not just to hearing, but also memory,” Husain said in an interview with News OK. “This created musical hallucinations. She didn’t just think about the music or the word, she thought she was hearing them.”
A Sound Explanation
According to researchers at Indiana University, the association cortex regions are the most developed parts of the human brain. The auditory association cortex is responsible for making the connection between something we hear and our memory of that sound.
Researchers hypothesized that, since the lesion was present in the area of the brain that’s used to process music, perhaps something known as the “release phenomenon” is to blame. A sort of never-ending loop of neural activity prevents the woman's brain from letting go of the songs and words no matter how much she would like to forget them.
This opens the door to a whole new area of exploration in MS research, as scientists study those regions of the brain to learn how the disease might manifest when deep white matter lesions like this occur. Hallucinations, like those experienced by the woman in this case, have rarely been reported in MS patients, but that may be due to physicians overlooking the possible connection.
The Band Plays On
Although this woman has yet to find relief from the band playing in her head, she is happy to know that researchers are finally taking her seriously. “Even her husband had trouble understanding what she was going through,” Husain said.
For healthy people who experience earworms, Dr. Jeremy Levin, who co-authored the study, said that it’s not an indication of damage, but rather, researchers suspect, “it’s just a memory replaying. Getting a song stuck in your head and having it play over and over can be easily replaced by listening to or thinking about something else. It may come back again but you do have the ability to get rid of it.”
While Husain admits that it is theoretically possible for the lesion causing this patient's earworm to eventually heal and disappear, so far that has not been the case. Instead, for over two years country stars have played a private—albeit unwanted—concert in her mind, and so far there’s no intermission in sight.