Harlow, H., (1958). The Nature of Love.
Arhe Vaninetti
Research Methods and Statistics, PSY 301, Pacific University, Oregon
February 6, 2023
Harlow’s groundbreaking research on the nature of attachment and affection between baby rhesus macaque monkeys and their surrogate, experimental mothers was established due to a lack of understanding on evolutionary love. Harlow found the existing psychological literature on basic needs to be lacking on the essential ingredient of love, affection and attachment. Viewed holistically, Harlow claimed that love was not a tertiary need of these neonatal monkeys, but instead a primary drive comparable to hunger and thirst. As Harlow mentions at the beginning of the research, he was interested in human-based needs for love, but could not commit to the research due to poor motor skills in the human infant and due to confounding variables.
Nonetheless, Harlow found that rhesus macaque monkeys were adequate for the research because of their similarities with human infants in attachment, as well as their growth and development rates. Once Harlow began his research with the infant monkeys, he was able to create two experimental groups and two control groups. The experimental group consisted of infant monkeys that were given a wire mother with milk and a barren cloth mother, or a barren wire mother and a cloth mother with milk. The surrogate mothers were identical in design, with the exception of the warmth and comfort that the cloth mother gave off.
For the other experimental group, both sets of infant monkeys were given barren wire and cloth mothers with no milk. Additionally, there was a group of monkeys that were given no mothers. Harlow found, as reported in numerous graphs, that the monkeys raised with the cloth mothers—regardless of the presence of milk—used them as a secure base and went to them for comfort, indicating the importance of attachment and love over the need for nourishment. At the end of the study, Harlow also reported that a certain premature monkey that was raised with an unfinished mother with a blank ball of wool for a head, preferred his cloth mother when she had no discernable features. Harlow also reported that this monkey would turn the face of the finished mother’s head to view the blank side. In this study, Harlow concludes with the notion that the research would be applicable to then-contemporary society due to women entering the job force and men beginning to care for infants, stating that it may become a luxury for infants to nurse through natural means.
While this study lacks solid statistical analyses, it makes up for it with clear and concise prose and form. Even while regarding the stream-of-consciousness writing, it is helpful in understanding the order of events, methodology, and concluding thoughts. The positive attributes of Harlow’s writing and statistical graphs are overshadowed, however, by the ethical implications of his research. While this research was (luckily) not performed on human infants, the rhesus macaque monkeys likely suffered from emotional toils from this experiment. Despite Harlow stating that human-reared infant monkeys had lower mortality rates than naturally reared monkeys, these monkeys were kept alive in isolation for the duration of the experiment. As Harlow suggests, due to attachment and love being so necessary to survival, it seems wrong for him to have deprived the monkeys of the ability to interact with others. Furthermore, while isolating these monkeys, Harlow fails to see his imbuement of anxious tendencies, as indicated by the rocking and fear-based behaviors. Glaringly, Harlow utilized a loud and obtrusive monkey-banging-a-symbol toy as the fear stimulus (as indicated in Figure 13). While the ethics of this study would not pass the 1973 Belmont Report, the findings could be expanded into the realms of social psychology through the research on lack of interaction in macaque monkeys. With the lack of socialization, could these monkeys still learn communal grooming behaviors or hierarchical dynamics, or would they struggle? Furthermore, would these monkeys have the same level of spacial awareness as socialized monkeys due to lack of cage space and territorial behavior from other monkeys? In essence, while this study has large flaws (mainly in the ethics department), it utilizes a consistent methodology, writing style, and research question, which is appreciable for this era of research in psychology.