Earlier quoted context omitted.
Hard as it may be to believe, earbuds/earphones/in-ear headphones were not invented with the iPod, or even the MP3 player. ;-) Today, many adults already have significant hearing loss from having regularly listened to loud music on portable players like the Walkman starting 30+ years ago. The first research on this seems to have been done in the mid-80's.
>"Hard as it may be to believe, earbuds/earphones/in-ear headphones were not invented with the iPod, or even the MP3 player" Believe I am well aware of that time before ipod/iphone/streaming services etc :) However back then there amount of time spent by people wearing earphone and headphones was much smaller comparison. Even with the existence of the Walkman it was not common to see people using them for instance in…
You're only considering adults. Teens definitely did spend hours a day with earbuds in.