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Harlow monkey experiments

The Harlow Monkey Experiments tested the bond between mother and child. Baby monkeys preferred a cloth "mother" that provided comfort over a wire "mother" that provided food. This showed that attachment is based more on comfort than nourishment. The cloth "mother" also acted as a secure base, encouraging exploration. Created by Brooke Miller.

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Video transcript

- [Voiceover] If you've ever been around young children, you're probably aware of the close bond that exists between mother and child, and scientists refer to this bond as attachment. But what causes this attachment? Why is there such a strong bond between mother and child? For years, scientist thought that it had to do with food. That a mom's unique ability to feed her child is what resulted in attachment. But that seems a little cold and kind of discounts all the things that mothers provide for their children. For example, contact comfort or the comfort that a child receives from being held by their mother. In order to find out exactly what causes this bond, scientists conducted a series of studies which are the Harlow Monkey Experiments. In these studies, baby monkeys were separated from their parents at a really young age. Which is something that we might consider to be kind of controversial today. But these monkeys were then given the choice to choose between two different substitute mothers. And I should note now that even though we're calling them mothers, we're actually referring to two different vaguely monkey shaped structures that were placed in the cage with the baby monkey. The first alternative mother option was the wire mother. And this was a mother that had a vaguely face like shape on top of it and then it had chicken wire that was kind of wrapped up in a cylinder as the body. and in the middle of that cylinder was a feeding tube. Which I'll put here in green and so within the cage that the monkey is in, this is the mother that can provide food. The second mother in the cage was referred to as the cloth mother, and this mother was the same size and shape as the wire mother, but instead of having exposed chicken wire, it had a soft cloth blanket that was wrapped around it, and so this mother is the mother that can provide comfort. So our monkey has been placed in this cage with two mother substitutes. Now, which mother do you think that the monkey is going to go to? Well, if you believe that food is the basis for attachment, then you would predict that the baby would go to the wire mother, because this is the mother with the feeding tube. This is the mother that can provide them food. On the other hand, if you think that attachment is based on things like comfort, then you would assume that the monkey would spend most of it's time around the cloth mother, because this is the mother that has the soft blanket, this is the mother that can provide contact comfort. Well it turns out that the baby monkeys overwhelmingly preferred the cloth mother. Indicating that it's comfort and not the ability to actually provide nourishment that forms the basis of attachment. In fact, these baby monkeys didn't just go to the cloth mother, they spent a large majority of their time absolutely clinging to her. In fact, when these monkeys did eventually need to eat, many of them tried to do it while clinging to the cloth mother. So they would keep part of their body wrapped around the cloth mother, while reaching over to the wire mother to try to feed from her. These monkeys simply did not want to lose contact with the cloth mother. They simply did not want to give up that comfort. And over a time these monkeys did eventually become more comfortable with their situation and they would sometimes move away from the cloth mother to explore the rest of their cage. But they would always return to the cloth mother afterwards, and because of this, we can refer to the cloth mother as being a secure base. And by that all I mean is that the baby monkey was secure in the knowledge that the cloth mother wasn't going anywhere. The baby monkey knew it could leave the cloth mother to explore, but that if it became anxious, that it would still be there when they got back. And so researchers would say that this pure attachment the baby monkey had with the cloth mother allows this cloth mother to act as a secure base, which eventually makes the monkey comfortable enough to explore the world on it's own.