(Taken from the 2005 documentary, Monkey Love.)
Harry Frederick Harlow (October 31, 1905 – December 6, 1981) was an American psychologist best known for his maternal-separation, dependency needs, and social isolation experiments on rhesus monkeys, which manifested the importance of caregiving and companionship in social and cognitive development. He conducted most of his research at the University of Wisconsin–Madison, where humanistic psychologist Abraham Maslow worked with him for a short period of time.
Harlow’s experiments were controversial; they included cultivating infant monkeys in isolation chambers for up to 24 months, from which they emerged intensely disturbed. Some researchers cite the experiments as a factor in the rise of the animal liberation movement in the United States. A Review of General Psychology survey, published in 2002, ranked Harlow as the 26th most cited psychologist of the 20th century.