Method
Brady yoked two monkeys together and administered electric shocks every 20 seconds for six-hour periods. One of the monkeys, the ‘executive,’ was able to press a lever that delayed the shocks for 20 seconds. However, it was unable to stop all shocks.
Results
Many of the ‘executives’ died of stomach ulcers.
Conclusion
Brady concluded it was the stress of being in control that had caused the ulcers. It couldn’t have been the shocks per se since the other monkey got the same number of shocks to its feet but didn’t get ulcers.
Evaluation
Where do you start?
Ethics: this is one of the cruellest experiments carried out in Psychology and would not be possible today. Relatively intelligent creatures were subjected to the pain and stress of foot shocks and died slow, painful deaths.
Method: The experiment appears to have been flawed. Weiss (1972) repeated the experiment on rats (these lack the aaahhh value of monkeys). He found no difference between ‘executives’ and ‘controls.’ The researchers noticed that in the original study Brady had used the most active and ‘extrovert’ monkeys as executives. They concluded that it wasn’t being in control that had killed the monkeys but their ‘personality’ or behaviour type.’
In another study Weiss preceded the shock with a warning tone. These executives were far less likely to develop ulcers which Weiss put down to the rats being able to ‘chill’ for some of the time. The effects of continual stress seemed far more damaging. This could be compared to some jobs such as air traffic controllers who need to maintain constant vigilance.