In Harlow's experiments, what material did he use to mimic contact comfort?

In Harlow's experiments, he utilized terry cloth to mimic contact comfort. His research involved infant rhesus monkeys, and he wanted to understand the importance of comfort and attachment in the development of these young primates. By using a soft, plush material like terry cloth, Harlow demonstrated that the infants preferred to cling to the soft surrogate mother, rather than a wire mother that provided food. This preference indicated that emotional support and comfort were critical elements of attachment, showcasing that physical touch and warmth significantly impact the behavior and development of young animals. The use of terry cloth successfully illustrated the concept of contact comfort, which was foundational in his studies on attachment.