Procedure of Harlow's study
Method used: Lab experiment
Independent variable:The two types of surrogate mothers - a harsh 'wire mother' which supplied milk and a soft 'towelling mother'
Dependent variable: Which mother would the monkey run to when frightened / distressed
What happened?1) Two types of surrogate mother were constructed - a harsh'wire mother' and a soft 'towelling mother'. Sixteen baby monkeys were used, four in each of four conditions:
• a cage containing a wire mother producing milk and a towelling mother producing no milk• a cage containing a wire mother producing no milk and a towelling mother producing milk• a cage containing a wire mother producing milk• a cage containing a towelling mother producing milk
2) The amount of time spent with each mother, as well as feeding time, was recorded.
3) The monkeys were frightened with a loud noise to test for mother preference during stress.
4) A larger cage was also used to test the monkeys' degree of exploration.