Combined-research* has revealed that silence is a generative force for our brains.
Mice exposed to 2 waking hours silence/day developed new cells in the hippocampus (a region of the brain associated with memory, emotion & learning) which then became functioning neurons. Relaxing music and sleep did not produce the same positive effects, and conversely, chronic (although not necessarily loud) noise levels resulted in impaired function.
The latter point will not surprise anyone unwillingly exposed to constant noise (she typed from beneath a pile of children on summer-break), but it may act to remind us that consciously spending just a small part of each day in silence, as an act of self-care, will do us the power of good.
*World Health Organization, the European Commission’s Joint Research Centre, The journal 'Brain, Structure and Function'.