I would just remember, in my own head, that she is stressed and lashing out. Because I love her I would feel sorry for her, wish to make her laugh and feel better/relax and for myself, I look at her comments logically.

Her IQ is higher than yours. So? I do not know if you have ever been to a MENSA meeting but it's got cab drivers all proud and thinking they are "smarter" than the average Joe. Everyone is smarter than some, less smart than others but the IQ test doesn't correspond to anything useful in reality? A high emotional IQ is much more to be desired (at least by me) than that you can solve EFEs with nine components missing Too, one's IQ scores can change slightly as one gets older; your mother has been around 20ish years longer than you have, has that much more experience -- her mother was smarter than she is at some point?

All you are good at is giving her migraines? You have to laugh at how lame that is! You should know yourself well enough to know you have more worth than that, that she enjoys being with and interacting with you and that you have all your years together and all those experiences against this one stressful moment? Put your hand over your heart and do a melodramatic, "Mother, you wound me!" act I guarantee she'll smile and probably apologize.