Attachment is a deep and enduring emotional bond that exists between one person and another and is not subject to the limits of time or proximity. It is usually first experienced in the relationship between child and primary caregiver.

Many developmental psychologists believe that attachment, the special relationship between infant and caregiver, creates the emotional foundation for later relationships and adult personality. Attachment plays such a central role in theories of social and emotional development that the scientific study of attachment remained in the early 2000s at the forefront of developmental psychology.

John Bowlby (1907–90), a psychoanalytically trained clinician, developed modern attachment theory in the 1950s as a version of object-relations theory. Bowlby integrated many approaches into his new theory, including evolutionary and systems theories. He formulated the modern theory of the unique, enduring qualities of infant-caregiver connections.

Before the widespread acceptance of Bowlby's theory, psychologists viewed attachment as a merely secondary drive, inferior to primary drives such as hunger. Theorists believed that children's attachment to their mother occurred simply because she supplied food. The mother became the object of the infant's attachment through association with feeding. She was important only for the reduction of primary needs. Behaviorist psychologists theorized that the need for attachment arose from an infant's physical needs for food and warmth, both of which were provided by the mother. A baby's preference for the mother was simply the result of conditioning.

Important research in the 1950s, however, cast these theories into doubt. One of the most famous research studies on attachment was performed by Harry Harlow (1905–81). In his experiment, Harlow placed infant monkeys in a cage with two surrogate mother dolls: one was made of wire holding a bottle of milk and the other was made of soft terry cloth fabric. According to the behaviorists, the monkeys should have developed a strong attachment to the wire mother; she was the source of food. However, the infant monkeys emphatically preferred the cloth mothers and attached themselves to those. This experiment suggested that the needs for comfort and warmth are actually more important and more psychologically ingrained than the need for food.

Bowlby became one of the first to map out stages of attachment in his 1980 book, Attachment and Loss. He suggested that from birth until three months old, babies are in an initial pre-attachment phase. Early on, infants simply need to be held and demonstrate no preference for who holds them. The next phase, attachment-in-themaking, takes place from three to four months and is marked by an infant's emerging preference to be held by people who are familiar; the person does not necessarily have to be the mother. According to Bowlby, the final stage is the clear-cut attachment phase. Beginning at about six months, this phase features an infant's clear insistence on its mother or primary caregiver.

Mary Ainsworth (1913–99), a prominent researcher in attachment and Bowlby's associate, devised a famous test to measure the type and degree of attachment a child feels for his mother. The test, called the Ainsworth Strange Situation Test, begins with a mother leading her child into a strange room; the child is free to explore with the mother present. Next, a stranger enters the room and the mother leaves. If the child becomes distressed, the stranger will try to console her. The mother then returns and the stranger leaves. Based on a child's response to the mother's return, children are labeled “securely attached,” “avoidant,” or “ambivalent.”

Attachment serves to help children begin to feel safe enough to explore the world. As studies show, if infants are presented with a strange situation, they either avoid or engage in exploration, and their decision chiefly depends upon whether they have an attachment figure nearby. Lack of attachment in early life can also have a negative impact on exploratory propensity in later years. In 1971, researchers separated a group of monkeys from their mothers for six days and then analyzed their behaviors two years later in comparison to a control group that had not undergone separation. The group that had been separated was observed to be far more reticent in exploratory behaviors than the control group. Still other studies indicate that even cognitive functioning (questioning and curiosity) in children is enhanced among “securely attached” (according to the Ainsworth scale) infants. People tend to transfer early patterns of attachment—anxious, secure, or avoidant—onto those they love in their adult life.

See also Ainsworth, Mary; Behaviorism ; Bowlby, John; Separation anxiety ; Stranger anxiety .



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