I can relate to this. I notice cognitive changes after 8 months on prednisone. I've had some problems with word-finding before but not completely going blank. I went to the grocery store to get some water chestnuts for an Asian dish I was cooking. I couldn't find them in the International section so headed to another section that has tofu. On the way I got distracted by marinated artichokes and picked up a jar of those. I finally found an employee and when I started asking him where the water chestnuts were my mind went completely blank. He was nice and knew what I was talking about when I described them. No, the store did not carry them!