inoculation effect media n. a psychological theory proposed by William J. McGuire (1925-2007) following the Korean War to explain how resistance to persuasion can be built up by through a process of exposure to weak counterarguments. Like a medical inoculation, which allows one to build up resistance to disease through exposure to small doses of a virus, attitudinal inoculation allows the individual to become actively defensive in strengthening beliefs, opinions, and attitudes in anticipation of future attacks by messages or arguments. SJ