Milgram completed research on obedience on 40 male participants between the ages of 20 and 50. He had them give electric shocks to a "learner", who was tasked on learning word pairs, every time they made an error. The shocks started at 15 volts but increased in increments of 15 volts to 450 volts. The participants were made to believe that the research was on the effect of punishment on learning but in fact the "learner" was a confederate and the experiment was investigating obedience to the "experimenter". When the participant, known as the "teacher", indicated they wanted to stop the experiment the "experimenter" would issue one of 4 prods from"please continue" to "you have no other choice, you must go on". The results were that 65% of participants continued until the full voltage and all participants reached 300v.