Ricky sometimes goes "ear blind" by choice, even standing next to me. But if I open a bag of his favorite treats, not just any bag, his favorite treats, he can identify the sound even when he is in the opposite end of the house and comes running full tilt to my side. An amazing recovery from deafness!Oh so funny! Willow knows all the sounds. Had a cat once that would come to the sound of a can opener. It was used only for the cat food can.