With her pioneering 'Strange Situation' study, psychologist Mary Ainsworth (1978) built upon Bowlby's ideas of attachment whilst pointing to the direct impact of attachment on behaviour. Her study involved researchers observing how children between the age of 12 and 18 months responded to a situation in which they were briefly left alone with a stranger and then reunited with their mothers.
Based on observations of these infants' behavioural responses, Ainsworth described three general styles of attachment:
Later, a fourth attachment style was introduced by researchers Main and Solomon (1986), which they called Disorganised-insecure Attachment.
On the next page you will see two videos which describe the above attachment styles whilst providing some current perspectives on attachment theory.