It is thought that mice are a fairly quiet animal, however they are a highly social animal that constantly communicate with one another via complex vocalisations. Their squeaks can be incredibly difficult to pick up as the frequency exceeds the limits of human hearing, therefore are difficult to separate from background noise.
A team from the University of Washington are investigating the effects of addictive drugs such as alcohols and opioids and have developed a piece of software to listen in on the chitchat of rats and mice. Called DeepSqueak, the program transforms audio signals into sonograms and visual representations of the sounds that can be analysed using Al techniques, similar to those that enable driverless cars to ‘see’ their environment. This will enable researchers to separate the rodents call from background noise.
“The animals have a rich repertoire of calls, around 20 kinds,” said Dr Kevin Coffey, a postdoctoral fellow in the University’s Neumaier lab. Coffey and his team found that male rodents made happy sounds when they were anticipating a reward. However, when the males sensed that a female was close, their vocalisations became far more complex, almost like they are singing a courtship song. This became far more dramatic when the male rodent could smell but not seen the female, almost suggesting they have distinct songs for various stages of courtship.
Due to its low cost and convenience it’s hoped this technique can eventually be used to investigate the effects of addictive drugs by monitoring psychological states of rodents in various stages of withdrawal.
“If scientists can understand better how drugs change brain activity to cause pleasure or unpleasant feelings, we could devise better treatments for addiction,” said laboratory director Prof John Neumaier.