I love reading about experiments performed in the 50s and 60s before all those pesky Ethical Review Boards(?)

>In an early version of the study, Brady placed monkeys in 'restraining chairs' and conditioned them to press a lever.[2] They were given electric shocks every 20 seconds unless they pressed the lever during the same time period. This study came to an abrupt halt when many of the monkeys died from perforated ulcers.