Provided a new understanding of human behavior and development through studies of social behavior of monkeys.
Theory
His theory hinged on the universal need for contact. Harlow's famous wire/cloth "mother" monkey studies demonstrated that the need for affection created a stronger bond between mother and infant than did physical needs (food).
Experiment
He separated baby monkeys from their mothers and used a wire mother- covered in soft cloth- with a nipple with milk- as a mother substitute for the baby. One day a baby monkey took a poop on the fake mother and Harlow had to wash the cloth. The baby monkey freaked out with the wire monkey without the soft cloth. So Harlow wanted to see if the cloth was really that important. He put baby monkeys into cages with two mothers- one with a soft cloth and no food, one a hard wire mesh with a nipple that provided food. To everyone's astonishment, the baby stayed with the cloth mother all day and ignored the one with food. Even when hungry the baby would quickly reach across, take some food, but run back to the soft mother. Thus, it was discovered that soft touch is critical for monkeys to develop attachment.
Critiques
George Miller & Robert Buckhout (1973) theorized that one contributing factor to the monkeys’ subsequent delinquent behavior would have been the lack of discipline imposed on ‘normal’ monkeys by their mother (usually in the form of a cuff around their head!) whenever behavior was unacceptable. Additionally the isolated monkeys would not have been in the presence of normal social monkey behavior from the earliest age, witnessing monkeys playing, grooming, presenting and mounting and the social cues that stimulated such behavior.
Although the sample size of the initial study was small, Harlow replicated the study numerous times and got similar results, indicating the results are reliable.
Although partly inspired by the theory of Maternal Deprivation, Bowlby then used Harlow’s work to support his