The brain gives two ways of evaluating suffering, as laid out by Nobel-Prize winning behavioral economist Daniel Kahneman in
Thinking, Fast and Slow. He studied a group of patients undergoing colonoscopy and kidney stone procedures. They rated their pain both during and after the procedure. Patients typically had low to moderate pain punctuated by spikes of significant pain while they experienced it. But afterward, their ratings were predicted by an average of the pain at two moments: the worst moment, and the very end, not according to the total amount (the Peak-End rule).