Key study


Ainsworth & Bell (1970)


The Strange Situation







The Strange Situation constitutes a standardised way of assessing individual differences in attachment. An infant is observed in a set sequence of seven episodes: with the mother (or caregiver); with the mother when a stranger is present; with just the stranger; and on its own. The infant’s reactions are observed providing measures of stranger fear and separation distress.




Ainsworth and Bell found that infants could be classified into one of three categories: anxious avoidant (Type A); securely attached (Type B); and anxious-resistant (Type B). Securely attached infants are relatively unconcerned by the stranger so long as the mother is present. They are distressed when the mother leaves but quickly reassured when she returns. Insecurely attached infants are either indifferent towards the mother (Type A) ambivalent towards her (distressed when she leaves but resist contact when she returns – Type C). The pattern of response varies from culture to culture, but in the West the proportions that fall into each category are roughly 20%, 70% and 10% respectively.




The conclusion of the Ainsworth & Bell’s study, which have been confirmed by numerous studies, is that infants do seem to fall into one of these categories (although there is also evidence for a fourth type: insecure-disorganised/disorientated) and the patterns remain constant (at least up to five years).




There have been some criticisms of her approach. Because it is generally carried out in the laboratory, the Strange Situation can be criticised as lacking ecological validity. The laboratory situation could induce a degree of stress in the infant that it would not normally experience at home.


The procedure has also been criticised for being limited in terms of the amount of information that is gathered (in contrast to less structured observational methods) and for not taking sufficiently into account the mother’s behaviour. It has also been suggested that the pattern of response is not consistent and can vary as family circumstances change, particularly the degree of stress that mothers are subjected to.


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