Harry Harlow : biography

October 31, 1905 - December 6, 1981

Overwhelmingly, the infant macaques preferred spending their time clinging to the cloth mother. Even when only the wire mother could provide nourishment, the monkeys visited her only to feed. Harlow concluded that there was much more to the mother/infant relationship than milk and that this “contact comfort” was essential to the psychological development and health of infant monkeys and children. It was this research that gave strong, empirical support to Bowlby’s assertions on the importance of love and mother/child interaction.

Successive experiments concluded that infants used the surrogate as a base for exploration and a source of comfort and protection in novel and even frightening situations.Harlow, H. F. (1958). The nature of love. In an experiment called the “open-field test,” an infant was placed in a novel environment with novel objects. When the infant’s surrogate mother was present, it clung to her, but then began venturing off to explore. If frightened, the infant would run back to the surrogate and cling to her for a time before sallying forth again. Without the surrogate mother’s presence, the monkeys were paralyzed with fear, huddling in a ball and sucking their thumbs.

In the “fear test,” infants were presented with a fearful stimulus, often a noisemaking teddy bear. Without the mother, the infants cowered and avoided the object. When the surrogate mother was present, however, the infant did not show great fearful responses and often contacted the device—exploring and attacking it.

Another study looked at the differentiated effects of being raised with only either a wire mother or a cloth mother. Both groups gained weight at equal rates, but the monkeys raised on a wire mother had softer stool and trouble digesting the milk, frequently suffering from diarrhea. Harlow's interpretation of this behavior, which is still widely accepted, was that a lack of contact comfort is psychologically stressful to the monkeys and the digestive problems are a physiological manifestation of that stress.

The importance of these findings is that they contradicted both the then common pedagogic advice of limiting or avoiding bodily contact in an attempt to avoid spoiling children and the insistence of the then dominant behaviorist school of psychology that emotions were negligible. Feeding was thought to be the most important factor in the formation of a mother-child bond. Harlow concluded, however, that nursing strengthened the mother-child bond because of the intimate body contact that it provided. He described his experiments as a study of love. He also believed that contact comfort could be provided by either mother or father. Though widely accepted now, this idea was revolutionary at the time.

Some of Dr. Harlow’s final experiments explored social deprivation in the quest to create an animal model for the study of depression. This study is the most controversial and involved isolation of infant and juvenile macaques for various periods of time. Monkeys placed in isolation exhibited social deficits when introduced or re-introduced into a peer group. They appeared unsure of how to interact with their conspecifics and mostly stayed separate from the group, demonstrating the importance of social interaction and stimuli in forming the ability to interact with conspecifics in developing monkeys, and, comparatively, in children.

Critics of Harlow's research have observed that clinging is a matter of survival in young rhesus monkeys, but not in humans, and have suggested that his conclusions, when applied to humans, overestimate the importance of contact comfort and underestimate the importance of nursing.Mason, W.A. Early social deprivation in the nonhuman primates: Implications for human behavior. 70-101; in D.C. Glass (ed.) Environmental Influences. New York: Rockefeller University and Russell Sage Foundation, 1968.

Harlow first reported the results of these experiments in "The Nature of Love", the title of his address to the sixty-sixth Annual Convention of the American Psychological Association, Washington, D.C., August 31, 1958.

Living octopus

Living octopus

In countries which are located near sea coasts, sea food is an important part of national cuisine