I do a lot of hiking and skiing between 3500 and 4500m and don't notice much cognitive degradation at those altitudes even when exercising hard. I do notice tha

I do a lot of hiking and skiing between 3500 and 4500m and don't notice much cognitive degradation at those altitudes even when exercising hard. I do notice that I'll get drunk much quicker around 4500m than I do where I live at 1700m