科学美国人60秒:熟悉的曲调能迅速唤醒大脑

This is Scientific American's 60-second Science, I'm Christopher Intagliata.
(CLIP: Tuning sound)
Remember scrolling through the radio dial, hoping a tune you liked would pop out of the static? You never had to listen too long to know you'd landed on a hit.
"Music has a really strong, remarkably strong, hold on us. So it's way enough to be exposed to a very brief snippet of a familiar song for us to be able to recognize it."
Maria Chait, an auditory cognitive neuroscientist at University College London.
Chait and her team recently studied how quick that reflex is. They started by asking 10 volunteers to name a feel-good, familiar song—like this:
(CLIP: Song 1)
Then the researchers handpicked a second tune that sounded similar but was unfamiliar to the volunteer.
(CLIP: Song 2)
They chopped both songs into tiny bits—each less than a second long—and then randomly interspersed them into a six-and-a-half-minute-long track of song snippets.
(CLIP: Snippet track)
As the snippets played, the scientists measured the volunteers' brain activity via a network of 128 electrodes and monitored changes in pupil diameter, too—a sign of arousal. And the researchers found that the listeners' pupils dilated more rapidly when they heard familiar versus unfamiliar samples—within just a tenth to a third of a second!

Familiar tunes also triggered a two-step pattern of brain activation almost identical to that seen in other memory studies—where the brain first recognizes something as familiar and then retrieves more detailed information about it. That pattern was absent for unfamiliar songs and for the control group.
The results are in the journal Scientific Reports.
The study does have limitations: it used a small number of songs; it was hard to mask the purpose of the study from the participants; and the control group ended up being primarily international students from Asia—since they had to be unfamiliar with every single song—so their native languages and music backgrounds differed from the experimental group—which was primarily students from a European background.
Still, for clinicians who want to use music as a therapeutic tool for patients with dementia, for example, this study might provide a few clues:
"There's a lot of interest in trying to develop so to speak objective measures of music enjoyment, of music familiarity. And this paradigm might be useful in this context, because it doesn't require the participant to indicate anything. They just listen passively."
Clinicians simply have to observe the neural fingerprints of hearing that same old song.
Thanks for listening for Scientific American's 60-second Science. I'm Christopher Intagliata.