Controversial experiment involving 22 orphaned children saw them get £730,000 compensation years later

In 1939, a controversial experiment on children was carried out which would go on to earn it the nickname 'monster study' and result in those still alive being awarded compensation years later.

There has been much research into the causes of stuttering and stammering, and how people might be able to work through speech impediments.

However, in this experiment conducted by Dr Wendell Johnson on 22 orphaned children in Iowa, the results left some of them feeling the effects for the rest of their lives.

The 22 children were split into two groups, those who showed signs of stuttering and those who didn't, and within those groups, they were split again.

Five stuttering children were told that they were actually speaking fluently and that they weren't stuttering, while another five were told they had speech problems and received speech therapy.

The study was conducted by Wendell Johnson, and left some children feeling the effects for the rest of their lives (University of Iowa)

In the other group, six fluently speaking children were told that they could speak well and were complimented on their ability to do so, while another six who could speak without stuttering were told that they were awful speakers who were developing stutters and were banned from speaking unless they could do so fluently.

These last six children very soon went from being able to speak fluently to hardly being able to talk at all.

Researchers wrote that in the case of a five-year-old girl, it 'was very difficult to get her to speak, although she spoke very freely the month before', while a nine-year-old was recorded as almost 'refusing to talk'.

They also noted that a 15-year-old talked less and started saying 'a' a lot, and when asked why she told researchers she was afraid of not being able to say the next word.

The academic ability of all six of the children in this group declined and they continued to suffer after the experiment was over.

The University of Iowa has a building named after the man who carried out the study (Facebook)

The results of the study were never actually published, though researchers knew about it and gave it the 'monster study' name. The results instead stayed in the University of Iowa until 2001 when an investigative journalist found them tucked away.

Jim Dyer of the San Jose Mercury News reached out to the people who had been experimented on, who told him they had suffered long-term psychological impacts.

In 2007, the state of Iowa agreed to pay $925,000 (£730,000) in compensation to the orphans.

NBC reported at the time that Hazel Potter Dornbush, an 84-year-old woman who had once been the 15-year-old girl who was afraid that she wouldn't be able to speak the next word, said: "It was awful stressful all these years. I’m just glad it’s over.

"How would you like to have them turn over all your past for the last 80 years?

"I call that brainwashing. I don’t care what anybody else calls it, that’s my language. I was wise to it right away, but I cooperated.

"You know we weren’t in no position to argue with nobody. We had nobody to lean on to help us out."

The University of Iowa still names its speech and hearing center after Wendell Johnson.