(Surrogate) Mother Love

1958

Harry Harlow (1905–1981)

Researchers at the Primate Laboratory at the University of Wisconsin in the 1950s were surprised when the young monkeys they had raised in isolation proved to be nearly useless in their studies of intelligence. The monkeys often were unresponsive to stimulation when brought in for experiments, looking away or becoming despondent. Then researchers noticed that the monkeys clung to the cloth diapers placed in their cages to cushion the cold floors. Building on this observation, lab director Harry Harlow designed experiments intended to shed light on, as he put it, the “origin of the infant’s love for his mother.”

In the 1950s, Harlow created a series of experiments to test his ideas about the importance of bodily contact, affection, and love. He published his first full account of these studies in 1958 in the journal American Psychologist. Two wire “mothers”—one bare, one covered in terry cloth—were created, each with a nipple for nursing. Eight newborn monkeys were given equal individual access to both mothers, with four being fed by the bare-wire mother and four fed by the terry-cloth-covered mother. There were no feeding differences between the two groups—the baby monkeys gained weight and grew regardless of which mother fed them; however, there were important differences in the psychological responses to the mothers. All eight monkeys spent much more of their time with the cloth-covered mother, and the amount only increased as they grew older. The dominant theories of the time predicted that the infants would spend more time with the mother that was the source of food, but Harlow showed that contact comfort was perhaps more important for bonding, attachment, and love.

In further experiments, Harlow found that the soft surrogate mother was an important refuge when the babies were frightened and seemed to serve as a secure base from which the infants could explore their environments. These findings complemented contemporaneous research on attachment by John Bowlby and Mary Ainsworth. Truly, love consists of more than nourishment.

SEE ALSO Failure to Thrive (1945), Attachment Theory (1969), The Strange Situation (1969)

Harlow’s experiments in the 1950s showed that baby monkeys require contact comfort for maternal attachment.