Mary Ainsworth: Attachment Theory and the Strange Situation

Mary Ainsworth (1913-1999), a Canadian-American developmental psychologist, was predominantly known for her contributions to attachment theory – including the Strange Situation experiment.

Attachment theory was one of the 20th century’s most influential theories of social, personality, and relationship development. Even now, it is described as “the dominant approach to understanding early social development”¹.

John Bowlby is most commonly attributed with the foundational work on attachment theory, and for good reason, as the core facets of the theory were based on his early experiences and career². However, Mary Ainsworth is recognized as a significant contributor to how we recognize attachment theory in modern-day psychology.

To help you understand Mary Ainsworth’s contributions to attachment theory, this article covers:

• A biography and background of Mary Ainsworth’s early life and career
• Mary Ainsworth’s contributions to attachment theory
• How Mary Ainsworth’s Strange Situation paradigm was established
• The classification of the attachment styles
• Mary Ainsworth’s further contributions to the field of psychology

Biography and Background of Mary Ainsworth

Mary Ainsworth’s Early Life

Born in Glendale, Ohio in 1913 and raised in Canada from the age of 4, Mary Ainsworth, née Salter, was the eldest of three girls. At the age of 15, Ainsworth was introduced to a book that would inspire her future endeavors in psychology: William McDougall’s Character and the Conduct of Life³.

DISCOVER YOUR ATTACHMENT STYLE

After graduating high school, Ainsworth pursued a degree in psychology at the University of Toronto beginning in 1929. Once she completed her undergraduate studies in 1935, she went on to earn her master’s degree and her PhD while working as a teaching assistant. In the midst of World War I, Ainsworth enlisted in the Canadian Women’s Army Corp and climbed to the rank of major.

After the war ended, Mary Ainsworth returned to the University of Toronto as an assistant professor, before marrying her husband, Leonard Ainsworth, and moving to London in 1950³.

Mary Ainsworth’s Career

After transitioning to London, Ainsworth joined forces with John Bowlby at the Tavistock Clinic where they researched the effects of disruptions to the mother-child bond on an infant’s psychological development³. What they found through their endeavors was that children are at risk of developmental issues when attachments between mothers and children are broken in some way.

After her time at the Tavistock Clinic, Ainsworth continued her research into the importance of the mother-child bond at the East African Institute for Social Research in Uganda in Kampala.

Returning to the US in the late 1950s and divorcing in 1960, Ainsworth taught at John Hopkins University until 1975. It was during this period that she underwent therapy which contributed to her interest in psychoanalysis. She then became a professor of psychology at the University of Virginia and remained there until 1984 when she decided to retire from teaching. She stayed active as a professor emeritus until 1992.

While it’s clear that Ainsworth had an eminent career, let’s consider her specific contributions to attachment theory.

Mary Ainsworth’s Attachment Theory

John Bowlby may predominantly be associated with attachment theory, but Mary Ainsworth’s attachment theory added significant contributions that shape how the theory is still discussed and used to this day.

The Strange Situation is the most well-known of Ainsworth’s contributions to attachment theory. During her time at John Hopkins, Ainsworth collaborated with a colleague, Sylvia Bell, to develop an assessment that measured the bond between mothers and their children – the Strange Situation⁴. During this assessment, a researcher (the “stranger”) observes a child’s response to when their mother leaves them alone in a room.

The Strange Situation is still highly regarded in its validity, and different variations are still used within modern-day research.

The Strange Situation experiment

Mary Ainsworth’s Strange Situation was developed to examine the attachment between mothers and children in an unknown environment.

During the original experiment, children between the ages of 49 and 51 weeks old from a sample of 56 white, middle-class American families were observed.

The setup for the experiment consisted of a small room filled with toys. The room also had a one-way glass window to facilitate the researcher’s covert observations of the child’s reactions.

The experiment involved eight steps, each with a duration of approximately three minutes. These steps are:

1. The mother and child are alone in the room
2. The child is encouraged to explore
3. A stranger enters the room and attempts to interact with the child
4. The mother leaves the room – the child and stranger are now alone
5. The mother returns and the stranger leaves
6. The mother leaves again
7. The stranger returns
8. The mother returns again and the stranger exits

Ainsworth and Bell used four criteria (separation; stranger anxiety; reunion behavior, and willingness to explore) to classify the children into one of three categories.

The Strange Situation measures how a child explores their environment in the presence of their caregiver, in their absence, and in the presence of a stranger. The original experiment drove the formation of the attachment classification system, allowing for a distinction between ambivalent and dismissive behaviors upon children’s reunion with their mothers.

In other words, how a child behaved during separation from and reunion with their mother revealed a lot about their form of attachment.

Types of Attachment Styles According to Ainsworth

Based on the findings of the Strange Situation, Ainsworth concluded that there were three types of attachment and developed the Strange Situation Classification⁵. This classification is still the cornerstone of how we categorize attachment behaviors today.

There are three attachment styles in the original Strange Situation Classification:

• Secure: The child demonstrates distress when separated from their caregiver. However, they are easily soothed by them on their return. They show preference to their parent over the stranger but are able to engage with the stranger. They explore freely and refer back to their secure base when uncertain (the caregiver).
• Anxious-ambivalent: The child displays high levels of distress when the caregiver leaves, but they are not comforted by their return. They are wary of the stranger and do not show as much exploration behavior.
• Anxious-avoidant: The child shows little preference for their caregiver over the stranger. They don’t react when the caregiver leaves and resist contact with them on their return. They don’t show much interest in exploring.

According to Ainsworth’s original findings, 70% of the children were secure, 15% were anxious-avoidant, and 15% were anxious-resistant.

The Addition of Disorganized Attachment

Mary Main, one of Ainsworth’s PhD students, noted that there was a specific subgroup of children who didn’t quite “fit” into the behaviors described by the other three attachment styles.

DISCOVER YOUR ATTACHMENT STYLE

This led to the classification of a fourth attachment pattern: the disorganized attachment pattern⁶. This style encapsulated infants whose behavior didn’t always align with an existing category, although it was intended to be used in addition to, rather than instead of, the other 3 categories. This means infants could be both anxious-avoidant and disorganized, for example.

This classification system led to countless subsequent studies on attachment and the different attachment styles.

Ainsworth’s Other Contributions to Psychology

Ainsworth’s work on the Strange Situation provided a framework for people to understand how children explored their environment. When a child has a secure attachment style, they use their caregivers as a “secure base” from which to explore and are comforted by their caregivers during times of distress.

However, children with insecure attachments don’t have this “secure base” from which to explore their world. They are not comforted by their caregiver’s presence, so maintaining proximity with them is their only source of safety.

Such findings challenged the traditional psychoanalytic and childcare viewpoints on development: attunement and sensitivity to a child’s needs rather than a strict routine leads to stronger bonds and healthier development.

Additionally, Ainsworth’s work emphasized the importance of the caregiver’s actions in determining the quality of the attachment bond – leading to the Caregiver Sensitivity Hypothesis. This hypothesis suggests that attachment styles are predicted by caregiver sensitivity.

Furthermore, the development of an attachment classification system allowed for extensive research into the impact of each. There is now a broad understanding that attachment styles are not fixed – they transition on the spectrum of attachment according to experiences. Also, attachment styles are no longer understood to be childhood-specific; they affect our adult patterns within relationships.

In general, the understanding is that people with a secure attachment style are more trusting of others and better able to effectively regulate their emotions. For these reasons, they tend to lead long-lasting and fulfilling relationships.

In contrast, insecure attachment styles are associated with distrust and emotional dysregulation, so people with these styles might see romance and love as more transient.

Conclusion and Future Perspectives on Ainsworth’s work

Although the Strange Situation wasn’t without controversy – for example, because it neglected the role of the father-child dynamic – it still contributed significantly to the field of developmental and social psychology. The attachment classification system which stemmed from its findings has helped shape our perspectives on caregiver sensitivity and emotional development for children.

Furthermore, Ainsworth’s classification system opened numerous avenues for research. These avenues include topics such as child-caregiver synchronicity and how much our early relationships continue to affect us throughout life, amongst others.

References

1. Crouch M. Attachment: What is it and Why is it so Important?. Kairaranga. 2015 Jul 1;16(2):18-23.
2. Bretherton I. The origins of attachment theory: John Bowlby and Mary Ainsworth. In Attachment theory 2013 Apr 15 (pp. 45-84). Routledge.
3. Russo NF, O’Connell AN, editors. Models of achievement: Reflections of eminent women in psychology. Columbia University Press; 1983.
4. Ainsworth MD, Bell SM. Attachment, exploration, and separation: Illustrated by the behavior of one-year-olds in a strange situation. Child development. 1970 Mar 1:49-67.
5. Ainsworth MDS, Wittig BA. Attachment and exploratory behavior of one-year-olds in a strange situation. In: Foss BM, editor. Determinants of infant behavior. Vol. 4. London: Methuen; 1969. p. 113–136.
6. Main M, Solomon J. Procedures for identifying infants as disorganized/disoriented during the Ainsworth Strange Situation. Attachment in the preschool years: Theory, research, and intervention. 1990;1:121-60.