Noise in cities destroys the brains of mice

The sounds of vehicles, honking, noise . no definite frequencies and rhythms destroy the auditory center on the brain and negatively affect the behavior of the mice taken to the city and live 2 months here.

Biologists publish this conclusion in the journal Nature Communications.

In the past, ecologists and biologists have had a lot of researches on the effect of city sound on the activities of birds, animals and plants.

For example, in August 2011 Dutch scientists saw noise in cities preventing corn finches from choosing objects to pair. In March 2012 a group of other biologists demonstrated that the honking of horns negatively affected California's pine forests, because the engine boom carried emissions that damaged pollen dispersal in the air.

Noise in cities destroys the brains of mice.

Similarly, Xiaoming Zhou, East China University in Shanghai and Michael Merzenich, University of California at San Francisco, tracked the impact of whistle on hearing and behavior of adult mice.

They split the mice into two groups, one group put in the barn with loudspeakers and the other group lived in normal conditions to be the control. In the one-speaker group emitted sounds from the city whistle, but at a low level, only about 50 to 60 decibels, equal to one-tenth of the real sound on the street, corresponding to the normal voice people. They are subjected to the continuous impact of these sounds around the clock. The second group placed in a quiet environment is like a rural area far from the city.

After 2 months, they conducted a series of meticulous measurements of hearing sensitivity, the ability to distinguish sounds but also the reaction of mice to those sounds to determine the negative impact of city noises. the animals compared to the control group.

The results showed that there were significant differences between the two groups of mice in terms of sensitivity, awareness and behavioral responses to situations. In mice in group 1, the noise damaged many nerve cells, corresponding to the differentiation of sounds. Reacting to the sounds repeated in them becomes slower, weaker.

'Our studies show that sound pollution in the city adversely affects the hearing of experimental mice such as destroying some neurons responsible for hearing and having negative effects. to their health. They are less flexible and respond to repetitive sounds , 'the researchers said.