When a good song is played, people can’t help but move with the music, nod their heads, or tap their feet to the beat of the rhythm. This ability to sense the beat and move in sync with it has only been thought to exist in humans and a small group of other species.
But even rats can keep the beat, according to a study published Friday in the journal Science Advances. Researchers in Japan played Mozart’s Sonata for Two Pianos in D Major (K. 448) to 10 rats, and tiny wireless accelerometers attached to the animals’ heads showed that the rodents subtly nodded to the beat of the music.
The research undermines a long-standing theory that the ability to synchronize body movements to musical rhythms is only found in animals, which can change the sounds they produce in response to experience. In addition to humans, these so-called vowel learners also include some birds, bats, elephants, whales, dolphins and seals.
Because rats aren’t voice learners, but rather bounce to the beat anyway, “clock synchronization may be more widespread in the animal kingdom than previously thought,” said Juan Manuel Toro, a comparative cognition researcher at Pompeu Fabra University in Barcelona, who wasn’t involved in the Research.
SHARE YOUR THOUGHTS
What other animals do you think can keep time like humans? Join the conversation below.
“This is the kind of work that needs to be done if we’re to uncover the tremendous abilities that other ways of connecting to the world we don’t yet know have,” said Nina Kraus, a professor of neurobiology at Northwestern University not involved in the new research.
dr Kraus said the finding didn’t surprise her. “It may be that they always had these abilities,” she said of rats. “It was just scientists who were slow to measure them.”
Previous research has looked at rats’ ability to perceive musical rhythms and move in sync with them. But that effort involved analyzing video footage of the animals’ movements that are “too small to be captured by visual inspection,” said Hirokazu Takahashi, an associate professor in the University of Tokyo’s Department of Mechanical Engineering and a co-author of the new learning.
The research team of Dr. Takahashi played 60-second clips of the sonata at four different tempos. Data from the accelerometers showed that five of the 10 rats moved their heads to the beat of the sonata when played at its original tempo of 132 beats per minute, or bpm. The researchers also saw a similar effect when the sonata was played at 75% of its original speed.
“First the rats wait and see, then they start moving and then those movements get stronger,” said Dr. Takahashi, adding that only some rats move rhythmically in response to music. “Some people show very large movements in response to music, others are very shy,” he said. “There are also many individual differences in rats.”
At faster tempos – when the sonata was played at double and quadruple speed – the rats didn’t move much.
Subscribe to Newsletter
The 10 point.
A personal, guided tour of the best scoops and stories each day in The Wall Street Journal.
The rats also heard songs by Lady Gaga, Queen, Michael Jackson and Maroon 5. However, the study focused on data collected when the animals were exposed to the Sonata, which Dr. Takahashi’s other rodent studies have been prevalent in cognition and behavior.
The researchers also recorded neuronal activity in another group of rats while subjecting them to clicks at different tempos. Using electrodes attached to the animals’ brains, they studied the auditory cortex, a brain region that processes sounds. The scientists found that the activity there was synchronized to the beat of rhythmic sounds with a tempo between 120 bpm and 140 bpm.
The research also included human study participants listening to the sonata in the four tempi using headphones equipped with accelerometers. Like the rats, humans’ movements synchronized most clearly with tempos between 120 bpm and 140 bpm. According to Dr. Takahashi sense, as evidenced by the fact that popular music often uses tempos in this range.
“The study is interesting because it shows clock synchronization in rats, and more importantly, it shows that the preferred tempos for such synchronization are the same as observed in humans,” said Dr. toro “This provides evidence for biological underpinnings of musical preferences shared by humans and other species.”
Henkjan Honing, a professor of music cognition at the University of Amsterdam, who was not involved in the new research, criticized the methodology. The rats’ head movements may simply have been a startling response to certain loud passages of music, he said.
“They’re basically scared,” he said of the rats.
To prove that the rats sense and synchronize to the beat, the researchers would need to show that the animals’ movements occurred a few milliseconds before the beats, said Dr. honey “It should be a little early and a little bit predictive,” he said, adding that the rats in the study responded to the hit instead of anticipating it.
A compelling follow-up study to this study, he said, would be if the researchers slowly speeded up or slowed down the music during the experiment and examined whether the rats’ physical responses changed over time, adapting to a new beat.
Although the new study provides no evidence that rats can predict the stroke, “that doesn’t mean it doesn’t exist,” said Dr. frizzy “Maybe we just weren’t smart enough to figure out how to measure it.”
Write to Aylin Woodward at [email protected]
Copyright ©2022 Dow Jones & Company, Inc. All rights reserved. 87990cbe856818d5eddac44c7b1cdeb8