A study conducted in 2015 showed that the complete absence of sound stimuli promotes the formation of new neurons in the hippocampus, which plays a key role in memory and learning processes in adult mice.
In this experiment, the animals were subjected to various sound conditions, including normal background noise, white noise, the sounds of ethologically significant signals (such as the cries of pups), structured music, and silence.
One day after exposure, the researchers observed an increase in the proliferation (division) of neural progenitors under all sound conditions. However, after a week, only those mice that were in silence showed a sustained increase in the number of new neurons, unlike those exposed to white noise or background sounds. This indicates that complete silence more effectively stimulates neurogenesis.
At first glance, it may seem surprising that the absence of sound elicits such a reaction. However, a study published in the journal PNAS in the summer of 2023 showed that silence is perceived by the brain similarly to sound, which can be interpreted as "hearing" the absence of sound.
Moreover, silence can serve as a powerful stimulus, as it is atypical for the natural environment and is perceived by the organism as a signal for heightened attention and adaptation. This need to adapt to "meaningful silence" may explain the brain's response. Despite the increasing amount of indirect evidence of neurogenesis in adult humans, caution should be exercised when transferring data obtained from rodents to the human brain.
The record Silence Generates New Neurons in the Brains of Adult Rodents first appeared on K-News.
