"brain fog" from other stuff too, seems to be it.
I've found these to be very helpful
https://www.youtube.com/watch?v=1sZdLGd9tFw
if your mom would adapt to one of these it may help her "hear" better and more clearer. and if she wants, put ear plugs in for awhile and experiment. Being "paired up" to my phone, and hands, free to do whatever they like, just builds confidence.
Bone conduction is just another way to perceive sound.
It may be all about the hands and keeping them in shape. little bags to squeeze helps.
Crazy thought, bring your acoustic guitar in and let her hands touch it while you are playing it. bone conduction is amazing.
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