Psychology research · Reference
What is attachment theory?
Attachment theory is a framework in developmental psychology describing how early emotional bonds between infants and caregivers shape patterns of relating, studied through methods such as the Strange Situation.
Definition and origin
Attachment theory was developed by the psychiatrist John Bowlby, who proposed that the bond between infant and caregiver is an evolved system promoting survival by keeping the infant close to a protector. The psychologist Mary Ainsworth turned the theory into an empirical research programme, devising methods to observe and classify attachment behaviour. The theory treats the early caregiver relationship as a foundation for an "internal working model" — a set of expectations about relationships — that researchers study as a developmental construct rather than as a basis for individual diagnosis.
The Strange Situation and attachment styles
Ainsworth’s Strange Situation is a structured laboratory procedure in which an infant experiences a sequence of separations from and reunions with a caregiver and a stranger. Observers code the infant’s behaviour, particularly at reunion, to classify attachment patterns.
The original classifications were secure, insecure-avoidant, and insecure-ambivalent (resistant); a fourth, disorganised, was later added by Mary Main and colleagues. These styles are research categories describing observed behaviour patterns, not labels of worth or fixed destinies.
Evidence and developments
Attachment research has grown into a large empirical literature spanning infancy to adulthood, including instruments such as the Adult Attachment Interview that assess how adults represent their early relationships. Studies have examined how attachment patterns relate to later social and emotional development, while also debating the strength and stability of these links and the influence of temperament and culture. As with any construct, findings are interpreted through the reliability and validity of the measures used and the design of the studies.
Significance for research
For measurement science, attachment theory is a notable example of translating a broad developmental idea into observable, codeable behaviour through the Strange Situation and related instruments. It illustrates the importance of standardised procedures, trained coders, and inter-rater reliability when measuring something as abstract as an emotional bond. The framework is presented here as a research construct within developmental psychology, not as clinical guidance or a tool for assessing individuals.
Key facts
At a glance
- Field: developmental psychology
- Originated by: John Bowlby
- Developed empirically by: Mary Ainsworth
- Key method: the Strange Situation procedure
- Styles: secure, avoidant, ambivalent, plus disorganised (Main)
- Framing: a research construct, not individual diagnosis
Common questions
FAQ
What is attachment theory?+
It is a developmental-psychology framework describing the emotional bonds between infants and caregivers and how these shape patterns of relating. It was originated by John Bowlby and developed into empirical research by Mary Ainsworth.
What is the Strange Situation?+
The Strange Situation is a structured laboratory procedure devised by Mary Ainsworth in which an infant goes through separations from and reunions with a caregiver. Trained observers code the infant’s behaviour to classify attachment patterns.
What are the attachment styles?+
The original styles were secure, insecure-avoidant, and insecure-ambivalent (resistant), with a fourth, disorganised, added later by Mary Main and colleagues. These are research categories describing observed behaviour, not fixed labels for individuals.
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