Rats bop to pop and respond to classical music as humans do
Humans aren’t the only beings able to bust a move on the dancefloor, with new research showing rats can also bop to the beat
READING LEVEL: ORANGE
Disco rats have thrown down a dancefloor challenge to humanity. Rhythm was always thought to be a skill unique to humans, but new research shows rats can also bop to the beat.
Nodding along to a catchy tune was found to depend on the speed at which our brains can respond to something, which is similar across all species – meaning that our auditory* and motor* systems’ ability to move to music may be shared.
WATCH THE VIDEO
The new discovery provides further insight into the animal mind as well as the origins* of human music and dance.
Whether you tap your toes in time or have two left feet, how well you move to music does depend a little on innate* genetic* ability and was previously thought to be a uniquely human trait*.
While animals do react to noise, make rhythmic sounds and can be trained to respond to music, none of these are the same as the complex neural* and motor processes that enable people to recognise the beat in a song, respond to it or even predict it – an ability known as “beat synchronicity*”.
But recent research studies and funny home videos have shown that some animals apparently share our human urge to move to the groove. And new research from the University of Tokyo reveals that rats are among them.
“Rats displayed innate — that is, without any training or prior exposure to music — beat synchronisation most distinctly within 120-140 bpm (beats per minute), to which humans also exhibit* the clearest beat synchronisation,” said University of Tokyo Associate Professor Hirokazu Takahashi from the Graduate School of Information Science and Technology.
“The auditory cortex*, the region of our brain that processes sound, was also tuned to 120-140 bpm, which we were able to explain using our mathematical model of brain adaptation.”
Previous studies have visually investigated animals’ responses to music, but wireless, miniature accelerometers* enabled this team to measure the slightest head movements.
But why play music to rats in the first place?
“Music exerts a strong appeal to the brain and has profound* effects on emotion and cognition*,” Dr Takahashi said. “To (use) music effectively, we need to reveal the neural mechanism underlying this empirical* fact.”
A specialist of electrophysiology*, which examines electrical activity in the brain, Dr Takahashi has studied the auditory cortex of rats for many years.
“After conducting our research with 20 human participants and 10 rats, our results suggest that the optimal tempo for beat synchronisation depends on the time constant in the brain,” said Dr Takahashi. “This demonstrates that the animal brain can be useful in elucidating* the perceptual* mechanisms of music.”
Human participants also wore accelerometers on headphones. They listened to Mozart’s* Sonata* for Two Pianos in D Major for one minute at four different tempos*: 75 per cent, 100 per cent, 200 per cent and 400 per cent of the original speed. The original tempo is 132bpm and results showed that the rats’ beat synchronicity was clearest within the 120-140 bpm range. The team also found that both rats and humans jerked their heads to the beat in a similar rhythm, and that the level of head jerking decreased the more that the music was sped up.
“To the best of our knowledge, this is the first report on innate beat synchronisation in animals that was not achieved through training or musical exposure,” said Dr Takahashi.
The study also offers some insight into the creation of music itself.
“Next I would like to reveal how other musical properties, such as melody and harmony, relate to the dynamics of the brain,” Dr Takahashi said. “I am also interested in how, why and what mechanisms of the brain create human cultural fields such as fine art, music, science, technology and religion.
“As an engineer, I am interested in the use of music for a happy life.”
GLOSSARY
- auditory: anything related to hearing
- motor: relates to moving and co-ordinating muscles in the body
- origins: the beginnings or causes of something
- innate: quality you are born with or naturally possess
- genetic: inherited, relating to genes and heredity
- trait: characteristic, attribute, distinguishing feature
- neural: involving the system of nerves that includes the brain
synchronicity: two or more related or similar events at the same time - exhibit: show, display, reveal
- cortex: outer layer, especially of the brain and other organs
- accelerometers: devices that measure acceleration or changes an object’s velocity
- profound: great, deep, important, very significant
- cognition: conscious mental processes like thinking and reasoning
- empirical: based on what is experienced or seen rather than on theory or hypotheses
- electrophysiology: biomedical field that studies electric activity in the body
- elucidating: explaining something or making it clear and plain
- perceptual: the ability to notice things, using senses to form an opinion about something
- Mozart: Wolfgang Amadeus Mozart, prolific Austrian composer, child prodigy; master of the classical style in all its forms of his time (1756-1791)
- sonata: piece of music in three or four parts, either for a piano or for another instrument
- tempo: rate of speed of music, movement or activity
EXTRA READING
Hip hop makes cheese taste great
Rafting rat starts long journey for Australian mammals
Brave rat rests up in well-earned retirement
QUICK QUIZ
- What is the range at which rats showed “beat synchronisation”?
- What region of the brain processes sound?
- How many human participants and how many rats participated in the study?
- What did they listen to?
- What were the four different tempos that were played?
LISTEN TO THIS STORY
CLASSROOM ACTIVITIES
1. 100 word challenge
Can you reduce the length of this news story to 100 words or less? Your new version should still include enough information for a reader to understand what was discovered by the University of Tokyo’s research.
Time: allow 30 minutes to complete this activity
Curriculum Links: English; Science
2. Extension
Choose a favourite song to listen to. Set a timer for one minute and try to count how many beats per minute there are in your chosen song. Is the tempo faster or slower than Mozart’s Sonata for Two Pianos in D Major?
Time: allow 15 minutes to complete this activity
Curriculum Links: English; Music
VCOP ACTIVITY
Wow word recycle
There are plenty of wow words (ambitious pieces of vocabulary) being used in the article. Some are in the glossary, but there might be extra ones from the article that you think are exceptional as well.
Identify all the words in the article that you think are not common words and particularly good choices for the writer to have used.
Select three words you have highlighted to recycle into your own sentences.
If any of the words you identified are not in the glossary, write up your own glossary for them.
Extension
Find a bland sentence from the article to up-level. Can you add more detail and description? Can you replace any base words with more specific synonyms?
Down-level for a younger audience. Find a sentence in the article that is high level. Now rewrite it for a younger audience so they can understand the words without using the glossary.