In 2011, Montreal researchers scanned the brains of volunteers listening to their favorite music. At the moment of chills, the brain released dopamine, the chemical messenger tied to pleasures like eating. Better still, another region released it a few seconds before the expected passage: your brain also savors the anticipation of the note to come.
Remembering is not replaying a recording — it is rebuilding. Each time you recall a memory, it becomes temporarily malleable and can be altered before being stored again. That is why two people can sincerely remember the same event… differently.
In 2003, Johnson and Goldstein compared European countries. Where you must tick a box to become a donor, consent rates ranged from 4% to 28%. Where you're a donor by default unless you opt out, they topped 85%. People aren't more generous on one side; most simply stick with whatever option was chosen for them.