“Apparently it is some kind of mental condition or disease.”
That is not a mental condition that is neurological.
I’ve heard of epileptic going into seizures after seeing certain colors of lights, mostly red ones or flashing strobe ones. This is the first time I’ve heard a noise doing it but anything is possible when it comes to epilepsy.
Well, they do not really know. He is dead for almost 800 years! No modern medicine then and The historian accounts are obviously not very detailed. He got some kind of seizures from sounds of ringing the bells and could not sleep when gold was present. Otherwise pretty healthy guy.
Modern historians think it might be epilepsy, but who knows.