Some People Hear Music That Isn’t There—and Scientists Think They Know Why

Here’s what you’ll learn when you read this story:

• While we’ve all had a tune frustratingly stuck in our head from time to time, some people experience auditory hallucinations that are indistinguishable from listening to real music.
• Scientists analyzed data from 80 subjects who experience this strange phenomenon, and found that they often experience other forms of hallucination or sensory distortion as well.
• The most compelling explanation for this brain glitch is deafferentiation theory, where the auditory cortex in people with hearing loss begins pulling music from our long-term memory for auditory processing.

While neuroscience has made gargantuan strides in understanding how the human mind works, the organ remains a labyrinth filled with medical mysteries—chief among them hallucinations. One of the best-known hallucinations is the so-called “phantom limb,” in which the brain continues to feel sensation from a limb that’s been amputated—and this “phantom” phenomenon can affect other senses as well.

For example, there’s Charles Bonnet Syndrome (CBS), named after the 18th-century Swiss naturalist who experienced visual hallucinations due to loss of vision—and the same is true for hearing as well. These musical hallucinations take the form of songs that sound just as real as music on the radio. The condition also goes by auditory CBS, or Oliver Sacks’ Syndrome, after the neurologist who wrote extensively about it.

Now, a new study published in the Journal of Neurology takes a closer look at this phenomenon in an attempt to establish baseline assumptions about the condition. Researchers from the Netherlands and the U.K. analyzed data from a cohort of 80 individuals who experienced musical hallucinations. Participants completed the Musical Hallucinations (MuHa) Questionnaire and underwent neuroimaging, auditory testing, and electroencephalograms (EEGs). Overall, the cohort skewed older, with a mean age of 65; causes included psychiatric disorders, hearing loss, and structural neurological damage.

Although experiences varied, the authors identified a few head-scratching trends. For example, those with asymmetric hearing loss typically heard these phantom tunes as coming from outside their heads, while most others perceived the music as originating within their own minds. They also found that a vast majority of the songs were examples of music from the past rather than newer music.

One theory, especially as it pertains to hearing loss, is that the auditory cortex gets “bored,” according to the Cleveland Clinic—and because its job is to process sound, it starts pulling music from a person’s memory. The authors call this deafferentiation theory, a kind of perceptual release in which “nonessential data stored in our memory systems can ‘break through’ and ‘be released into’ consciousness due to pathological processes that break down inhibitory mechanisms,” they write. They also note that musical hallucinations can have a connection with epilepsy, but found only two participants in the study that fit that particular description.

Interestingly, this music isn't pulled from the Billboard Hot 100, but rather from songs often associated with childhood. A 2005 study in the International Journal of Geriatric Psychiatry reported that these hallucinations were often religious in nature, or otherwise related to holiday or children’s songs. This new study reports a similar finding, with religious songs the most commonly reported at 18 percent. That once again suggests the brain is reaching into long-term memory for tunes learned in childhood, rather than recycling newer music.

For most of us, an earworm is a temporary annoyance—often solved by an impromptu karaoke session in the isolated comfort of a highway-bound automobile. These hallucinations are different: only one-fifth of participants reported having any control over them, such as playing real music to drown out the phantom tunes.

“Having difficulty concentrating and sleeping, and suffering from the unrelenting onslaught of music, in the end many become exhausted and depressed,” the authors note, adding that people with this condition are often reluctant to pursue help for fear of a diagnosis of psychosis or dementia. “In more than 65% of the cases the music was rated as burdensome. Moreover, most of the participants had very little control over their hallucinations, and mostly only fleeting.”

Treatment can vary depending on the underlying cause which, as this study lays out, can be varied. Antipsychotics and other psychotropic medications can help, as can therapy aimed at explaining the underlying science. The goal is to de-stigmatize the condition and instill a sense of acceptance that much about the human mind remains a mystery.