To a chef, the sounds of lip smacking, slurping and swallowing are the highest form of flattery (恭维). But to someone with a certain type of misophonia (恐音症), these same sounds can be torturous. Brain scans are now helping scientists start to understand why.
People with misophonia experience strong discomfort, annoyance or disgust when they hear particular triggers. These can include chewing, swallowing, slurping, throat clearing, coughing and even audible breathing. Researchers previously thought this reaction might be caused by the brain overactively processing certain sounds. Now, however, a new study published in Journal of Neuroscience has linked some forms of misophonia to heightened “mirroring” behavior in the brain: those affected feel distress while their brains act as if they were imitating the triggering mouth movements.
“This is the first breakthrough in misophonia research in 25 years,” says psychologist Jennifer J. Brout, who directs the International Misophonia Research Network and was not involved in the new study.
The research team, led by Neweastle University neuroscientist Sukhbinder Kumar, analyzed brain activity in people with and without misophonia when they were at rest and while they listened to sounds. These included misophonia triggers (such as chewing), generally unpleasant sounds (like a crying baby）, and neutral sounds. The brain’s auditory (听觉的) cortex, which processes sound, reacted similarly in subjects with and without misophonia. But in both the resting state and listening trials, people with misophonia showed stronger connections between the auditory cortex and brain regions that control movements of the face, mouth and throat, while the controlled group didn’t. Kumar found this connection became most active in participants with misophonia when they heard triggers specific to the condition.
“Just by listening to the sound, they activate the motor cortex more strongly. So in a way it was as if they were doing the action themselves,” Kumar says. Some mirroring is typical in most humans when witnessing others’ actions; the researchers do not yet know why an excessive(过分的) mirroring response might cause such a negative reaction, and hope to address that in future research. “Possibilities include a sense of loss of control, invasion of personal space, or interference with current goals and actions,” the study authors write.
Fatima Husain, an Illinois University professor of speech and hearing science, who was not involved in the study, says potential misophonia therapies could build on the new findings by counseling patients about handling unconscious motor responses to triggering sounds—not just coping with the sounds themselves. If this works, she adds, one should expect to see reduced connected activity between the auditory and motor cortices.
【小题1】It can be learnt from the new study that ______.| A．misophonia sufferers can’t help imitating the triggers |
| B．people with misophonia are more likely to flatter chefs |
| C．the brains of people with misophonia overreact to sounds strongly |
| D．misophonia sufferers tend to have similar annoying activities in their brains |
| A．suffer less severely at the resting state | B．own markedly different brain structures |
| C．react more negatively at a mirroring response | D．lose control of their facial movements easily |
| A．Improving speech and hearing science. | B．Developing a treatment for misophonia. |
| C．Drawing people’s attention to misophonia. | D．Promoting human brain structure research. |
