What Is Attachment Theory?

The Importance of Early Emotional Bonds

Attachment theory focuses on relationships and bonds (particularly long-term) between people, including those between a parent and child and between romantic partners. It is a psychological explanation for the emotional bonds and relationships between people.

This theory suggests that people are born with a need to forge bonds with caregivers as children. These early bonds may continue to have an influence on attachments throughout life.

Stages of Attachment
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History of the Attachment Theory

British psychologist John Bowlby was the first attachment theorist. He described attachment as a "lasting psychological connectedness between human beings." Bowlby was interested in understanding the anxiety and distress that children experience when separated from their primary caregivers.

Thinkers like Freud suggested that infants become attached to the source of pleasure. Infants, who are in the oral stage of development, become attached to their mothers because she fulfills their oral needs.

Some of the earliest behavioral theories suggested that attachment was simply a learned behavior. These theories proposed that attachment was merely the result of the feeding relationship between the child and the caregiver. Because the caregiver feeds the child and provides nourishment, the child becomes attached.

Bowlby observed that feedings did not diminish separation anxiety. Instead, he found that attachment was characterized by clear behavioral and motivation patterns. When children are frightened, they seek proximity from their primary caregiver in order to receive both comfort and care.

Understanding Attachment

Attachment is an emotional bond with another person. Bowlby believed that the earliest bonds formed by children with their caregivers have a tremendous impact that continues throughout life. He suggested that attachment also serves to keep the infant close to the mother, thus improving the child's chances of survival.

Bowlby viewed attachment as a product of evolutionary processes. While the behavioral theories of attachment suggested that attachment was a learned process, Bowlby and others proposed that children are born with an innate drive to form attachments with caregivers.

Throughout history, children who maintained proximity to an attachment figure were more likely to receive comfort and protection, and therefore more likely to survive to adulthood. Through the process of natural selection, a motivational system designed to regulate attachment emerged.

The central theme of attachment theory is that primary caregivers who are available and responsive to an infant's needs allow the child to develop a sense of security. The infant learns that the caregiver is dependable, which creates a secure base for the child to then explore the world.

So what determines successful attachment? Behaviorists suggest that it was food that led to forming this attachment behavior, but Bowlby and others demonstrated that nurturance and responsiveness were the primary determinants of attachment.

Ainsworth's "Strange Situation"

In her research in the 1970s, psychologist Mary Ainsworth expanded greatly upon Bowlby's original work. Her groundbreaking "strange situation" study revealed the profound effects of attachment on behavior. In the study, researchers observed children between the ages of 12 and 18 months as they responded to a situation in which they were briefly left alone and then reunited with their mothers.

Based on the responses the researchers observed, Ainsworth described three major styles of attachment: secure attachment, ambivalent-insecure attachment, and avoidant-insecure attachment. Later, researchers Main and Solomon (1986) added a fourth attachment style called disorganized-insecure attachment based on their own research.

A number of studies since that time have supported Ainsworth's attachment styles and have indicated that attachment styles also have an impact on behaviors later in life.

Maternal Deprivation Studies

Harry Harlow's infamous studies on maternal deprivation and social isolation during the 1950s and 1960s also explored early bonds. In a series of experiments, Harlow demonstrated how such bonds emerge and the powerful impact they have on behavior and functioning.

In one version of his experiment, newborn rhesus monkeys were separated from their birth mothers and reared by surrogate mothers. The infant monkeys were placed in cages with two wire-monkey mothers. One of the wire monkeys held a bottle from which the infant monkey could obtain nourishment, while the other wire monkey was covered with a soft terry cloth.

While the infant monkeys would go to the wire mother to obtain food, they spent most of their days with the soft cloth mother. When frightened, the baby monkeys would turn to their cloth-covered mother for comfort and security.

Harlow's work also demonstrated that early attachments were the result of receiving comfort and care from a caregiver rather than simply the result of being fed.

The Stages of Attachment

Researchers Rudolph Schaffer and Peggy Emerson analyzed the number of attachment relationships that infants form in a longitudinal study with 60 infants. The infants were observed every four weeks during the first year of life, and then once again at 18 months.

Based on their observations, Schaffer and Emerson outlined four distinct phases of attachment, including:

Pre-Attachment Stage

From birth to 3 months, infants do not show any particular attachment to a specific caregiver. The infant's signals, such as crying and fussing, naturally attract the attention of the caregiver and the baby's positive responses encourage the caregiver to remain close.

Indiscriminate Attachment

Between 6 weeks of age to 7 months, infants begin to show preferences for primary and secondary caregivers. Infants develop trust that the caregiver will respond to their needs. While they still accept care from others, infants start distinguishing between familiar and unfamiliar people, responding more positively to the primary caregiver.

Discriminate Attachment

At this point, from about 7 to 11 months of age, infants show a strong attachment and preference for one specific individual. They will protest when separated from the primary attachment figure (separation anxiety), and begin to display anxiety around strangers (stranger anxiety).

Multiple Attachments

After approximately 9 months of age, children begin to form strong emotional bonds with other caregivers beyond the primary attachment figure. This often includes a second parent, older siblings, and grandparents.

Factors That Influence Attachment

While this process may seem straightforward, there are some factors that can influence how and when attachments develop, including:

  • Opportunity for attachment: Children who do not have a primary care figure, such as those raised in orphanages, may fail to develop the sense of trust needed to form an attachment.
  • Quality caregiving: When caregivers respond quickly and consistently, children learn that they can depend on the people who are responsible for their care, which is the essential foundation for attachment. This is a vital factor.

Attachment Styles

There are four patterns of attachment, including:

  • Ambivalent attachment: These children become very distressed when a parent leaves. Ambivalent attachment style is considered uncommon, affecting an estimated 7% to 15% of U.S. children. As a result of poor parental availability, these children cannot depend on their primary caregiver to be there when they need them.
  • Avoidant attachment: Children with an avoidant attachment tend to avoid parents or caregivers, showing no preference between a caregiver and a complete stranger. This attachment style might be a result of abusive or neglectful caregivers. Children who are punished for relying on a caregiver will learn to avoid seeking help in the future.
  • Disorganized attachment: These children display a confusing mix of behavior, seeming disoriented, dazed, or confused. They may avoid or resist the parent. Lack of a clear attachment pattern is likely linked to inconsistent caregiver behavior. In such cases, parents may serve as both a source of comfort and fear, leading to disorganized behavior.
  • Secure attachment: Children who can depend on their caregivers show distress when separated and joy when reunited. Although the child may be upset, they feel assured that the caregiver will return. When frightened, securely attached children are comfortable seeking reassurance from caregivers. This is the most common attachment style.

The Lasting Impact of Early Attachment

Children who are securely attached as infants tend to develop stronger self-esteem and better self-reliance as they grow older. These children also tend to be more independent, perform better in school, have successful social relationships, and experience less depression and anxiety.

Research suggests that failure to form secure attachments early in life can have a negative impact on behavior in later childhood and throughout life.

Children diagnosed with oppositional defiant disorder (ODD), conduct disorder (CD), or post-traumatic stress disorder (PTSD) frequently display attachment problems, possibly due to early abuse, neglect, or trauma. Children adopted after the age of 6 months may have a higher risk of attachment problems.

Attachment Disorders

In some cases, children may also develop attachment disorders. There are two attachment disorders that may occur: reactive attachment disorder (RAD) and disinhibited social engagement disorder (DSED).

  • Reactive attachment disorder occurs when children do not form healthy bonds with caregivers. This is often the result of early childhood neglect or abuse and results in problems with emotional management and patterns of withdrawal from caregivers.
  • Disinhibited social engagement disorder affects a child's ability to form bonds with others and often results from trauma, abandonment, abuse, or neglect. It is characterized by a lack of inhibition around strangers, often leading to excessively familiar behaviors around people they don't know and a lack of social boundaries.

Adult Attachments

Although attachment styles displayed in adulthood are not necessarily the same as those seen in infancy, early attachments can have a serious impact on later relationships. Adults who were securely attached in childhood tend to have good self-esteem, strong romantic relationships, and the ability to self-disclose to others.

A Word From Verywell

Our understanding of attachment theory is heavily influenced by the early work of researchers such as John Bowlby and Mary Ainsworth. Today, researchers recognize that the early relationships children have with their caregivers play a critical role in healthy development. 

Such bonds can also have an influence on romantic relationships in adulthood. Understanding your attachment style may help you look for ways to become more secure in your relationships.

9 Sources
Verywell Mind uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. Bowlby J. Attachment and Loss. Basic Books.

  2. Bowlby J. Attachment and loss: Retrospect and prospect. Am J Orthopsychiatry. 1982;52(4):664-678. doi:10.1111/j.1939-0025.1982.tb01456.x

  3. Draper P, Belsky J. Personality development in the evolutionary perspective. J Pers. 1990;58(1):141-61. doi:10.1111/j.1467-6494.1990.tb00911.x

  4. Ainsworth MD, Bell SM. Attachment, exploration, and separation: Illustrated by the behavior of one-year-olds in a strange situation. Child Dev. 1970;41(1):49-67. doi:10.2307/1127388

  5. Main M, Solomon J. Discovery of a new, insecure-disorganized/disoriented attachment pattern. In: Brazelton TB, Yogman M, eds., Affective Development in Infancy. Ablex.

  6. Harlow HF. The nature of love. American Psychologist. 1958;13(12):673-685. doi:10.1037/h0047884

  7. Schaffer HR, Emerson PE. The development of social attachments in infancy. Monogr Soc Res Child Dev. 1964;29:1-77. doi:10.2307/1165727

  8. Lyons-Ruth K. Attachment relationships among children with aggressive behavior problems: The role of disorganized early attachment patterns. J Consult Clin Psychol. 1996;64(1):64-73. doi:https:10.1037/0022-006X.64.1.64

  9. Young ES, Simpson JA, Griskevicius V, Huelsnitz CO, Fleck C. Childhood attachment and adult personality: A life history perspective. Self and Identity. 2019;18:1:22-38. doi:10.1080/15298868.2017.1353540

Additional Reading
  • Ainsworth MDS, Blehar MC, Waters E, Wall S. Patterns of Attachment: A Psychological Study of the Strange Situation. Erlbaum.

  • Ainsworth MDS. Attachments and other affectional bonds across the life cycle. In: Attachment Across the Life Cycle. Parkes CM, Stevenson-Hinde J, Marris P, eds. Routledge.

  • Bowlby J. The nature of the child's tie to his mother. Int J Psychoanal. 1958;39:350-371.

By Kendra Cherry, MSEd
Kendra Cherry, MS, is a psychosocial rehabilitation specialist, psychology educator, and author of the "Everything Psychology Book."