OAEs are considered to be related to the amplification function of the cochlea. In the absence of external stimulation, the activity of the cochlear amplifier increases, leading to the production of sound. Several lines of evidence suggest that, in mammals, outer hair cells are the elements that enhance cochlear sensitivity and frequency selectivity and hence act as the energy sources for amplification. One theory is that they act to increase the discriminability of signal variations in continuous noise by lowering the masking effect of its cochlear amplification.
There is a lot to like about The Nourishing Traditions Book of Baby and Child Care by Sally Fallon Morrell and Thomas S Cowan. Some of it is exceptionally well-researched (other things I thought were a little sketchy or questionable, see further below). I could never list all the awesome things the book discusses, but some of the highlights for me include:
Your government contends that these changes are necessary because they will “increase access”. To the contrary, analyses by public entities and community service providers show that “new” infant rooms with a younger, narrower age range at a very high fee will close and that there will be severe financial and practical effects that affect service viability across age groups.