It would be an overstatement to claim that a single book transformed modern culture. One could view One Flew Over the Cuckoo's Nest by Ken Kesey as part of a larger movement to reconsider treatment of mental illness in the 1960s. It was one of several works questioning the safety of electroshock therapy. It also problematized the then-modern understanding and treatment of mental illness.

Electroconvulsive therapy (ECT) is a method of treating severe mental illness. It involves administering small electric currents through the brain. In the 1960s, psychiatrists administered high doses of electricity, without anesthesia, on patients. This practice had many negative effects on patients. Kesey's dramatization of the issue contributed to public awareness. Greater awareness helped change protocols for administering ECT.

Another issue tackled in the novel is the degree to which treatment of mental illness is a social control mechanism. Kesey (along with other thinkers) questions if diagnoses reflect a dysfunction in society as much as in the individual. Ronald David Laing (7 October 1927 – 23 August 1989), a counter-cultural psychiatrist, was a significant figure in this movement. The seminal 1961 work Madness and Civilization: A History of Insanity in the Age of Reason by the French philosopher Michel Foucault also contributed to new understanding of the issue.

Kesey's work is best seen as a part of a larger movement in the late 1950s and early 1960s. He, along with others, changed cultural understanding around the nature and treatment of mental illness.