Taking the baby into a bright room with lots of background noise, to add as much background stimulus as possible. (askmoxie.org)
This also means the speaker can be audible in situations with lots of background noise. (digitaltrends.com)
An environment most conducive to your child's learning style matters, too: Some kids prefer quiet solitude while others do better with lots of background noise to stimulate the senses. (verywellfamily.com)