How does one flew over the cuckoos nest connect to the time period?

I'll take a stab at this. I believe it connects to the time period because of the archaic way they used to treat people with mental disorders. Do a search on wiki about frontal lobotomies, electric shock treatment (EST) and maybe delve into some of the words used in the novel that do not seem politically correct these days. Take a look at the link below, it shows the dates that the Lobotomy was in it's hay-day.