There was an elderly couple who in their old age noticed that they were getting a lot more forgetful, so they decided to go to the doctor. The doctor told them that they should start writing things down so they don't forget.
They went home and the old lady told her husband to get her a bowl of ice cream. "You might want to write it down," she said. The husband said, "No, I can remember that you want a bowl of ice cream."
She then told her husband she wanted a bowl of ice cream with whipped cream. "Write it down," she told him, and again he said, "No, no, I can remember: you want a bowl of ice cream with whipped cream."
Then the old lady said she wants a bowl of ice cream with whipped cream and a cherry on top. "Write it down," she told her husband and again he said, "No, I got it. You want a bowl of ice cream with whipped cream and a cherry on top."
So he goes to get the ice cream and spends an unusually long time in the kitchen, over 30 minutes. He comes out to his wife and hands her a plate of eggs and bacon. The old wife stares at the plate for a moment, then looks at her husband and asks, "Where's the toast?"