Ainsworth - strange situation

• Ainsworth's aim


  • to produce a method for assessing quality of attachment by placing an infant in a situation of mild stress to encourage them to seek comfort and encouraging exploration
  • seeking comfort and encouraging exploration are indicators of the quality of attachments
• Ainsworth's procedure: Who and what was involved?

  • 100 middle class american infants and their mothers
  • method of controlled observation was developed, this involved observing infants with their mother during a set of pre-determined activities- all sessions taking 3 minutes
• Ainsworth's procedure: Method


  1. mother and child enter the room
  2. mother and child are left alone and child can investigate the toys
  3. a stranger enters the room and talks with the mother, stranger gradually approaches the infant with a toy and the mother leaves her child alone with stranger who attempts to interact with the child
  4. mother returns to greet and comfort the child
  5. child is left on its own until stranger returns and tries to engage with child
  6. mother returns greeting and picking up the child - stranger leaves inconspicuously
• What did the observers make notes on?

  • separation anxiety
  • infant willingness to explore
  • stranger anxiety
  • reunion behaviour
• What did Ainsworth find?

  Ainsworth classified the infants into 3 groups

  1. securely attached infants
  2. insecurely avoidant infants
  3. insecurely resistant infants
• FINDINGS: Group 1 


  • securely attached infants
  • 66% of infants were classified into this group
  • explored, upset when mum left and relived when she returned
• FINDINGS: Group 2


  • insecurely avoidant infants
  • 22% of infants were classified into this group
  • didn't seem concerned at mothers absence and showed little interest when she returned
• FINDINGS: Group 3 


  • insecurely resistant infants
  • 12% of infants classified into this group
  • intense distress when mother was absent and rejected her when she returned
• Ainsworth's conclusions


  • shows that there are significant individual differences between infants and can be represented with 3 broad categories
  • all children who were observed were securely attached (north american culture)
  • appears to be an association between mother's behaviour and infant's attachment - suggesting the mother's behaviour may be important when determining attachment type
• Evaluation of Ainsworth's study

  • low population validity - unreasonable to make generalisations about all infant behaviour on the basis of this sample of middle-class americans
  • in a later study, Main and Cassidy identified a further group of children referred to as 'disorganised' - inconsistent behaviour