15 Most Disturbing Experiments in Human History

5. The Monster Study

Never let it be said that positive reinforcement isn’t the best way to raise your kids. In 1926, Wendell Johnson and Mary Tudor conducted an experiment with 22 students in an Iowa classroom. Separated into two groups, one group was given gentle encouragement positive reinforcement in learning their speech patterns. The other group, meanwhile, was scolded harshly while learning. Unsurprisingly, the latter group endured serious speech impediments throughout their life.