[2] John Bowlby originally proposed the concept of the 'attachment behavioral system', an orientation and set of dispositions which evolved because it provided protection from predation and other risks to survival.
A collaborator of Bowlby's, Mary Ainsworth, developed a standardised laboratory observation procedure named the 'Strange Situation' in which an infant would undergo two brief separations and reunions from their caregiver as well as contact with a stranger.
Whilst it might seem odd or maladaptive at first sight for a child to turn away from their caregiver when anxious, Main argued from an evolutionary perspective that avoidance could be regarded as a strategy to achieve the protective proximity enjoined by the attachment system - but which responds to the context of a caregiver who would rebuff them and be less available if the infant made a direct appeal for contact and comfort.
She has since remained at Berkeley, though she has also held visiting scholar positions at the Centre for Interdisciplinary Research in Bielefeld (Germany) and the University of Leiden (Netherlands).
During her year with Karin and Klaus Grossmann at the Centre for Interdisciplinary Research in 1977, Main interacted with various biologists, evolutionary theorists and ethologists, including Richard Dawkins and Robert Hinde, who influenced her thinking about conflict behaviors.
She also helped Karin and Klaus Grossman with their Bielefeld longitudinal study, including encouraging them to analyse the role of fathers in infants' attachment development.
In this text, she draws from Tinbergen the important distinction between 'proximal' and 'ultimate' causation, noting that immense confusion about attachment arises when these levels of analysis are mistaken for one another.
"[8] In her attention to attachment as an evolutionary phenomenon, from early in her career Main was already reflecting that a conflict might arise between an infant's experience of aversive parenting and the attachment injunction to seek protection from a caregiver: Peculiar maltreatment effects – that is, the irrational return of the abused to the abusing object – were first noted by Darwin (1972) in his voyage to the Galapagos; they were presented along with an explanation of the mechanism.
"Perhaps this singular piece of apparent stupidity may be accounted for by the circumstance that this reptile has no enemy whatever on shore, whereas at sea it must often fall prey to the numerous sharks.
[16] For example, this classification in infancy has been found associated with school-age externalising problem behavior,[17] indices of dissociation in adolescence[18] and development of post-traumatic stress symptoms following trauma exposure.
[20] A meta-analysis of 4 samples involving 223 children found a significant association between disorganization and school age controlling attachment behavior.
[21] Main conceptualised disorganization/disorientation as representing some form of contradiction or disruption of the attachment system: either a conflict between simultaneous dispositions to physically approach and to flee the caregiver, or seeming disorientation to the environment.
[24] As Lyons-Ruth et al. have recently observed, "to date, few hypotheses have been advanced regarding the mechanisms underlying this striking difference among infants who display disorganized behavior".
For example, unresolved loss,[31] parental experiences of helplessness,[32] a parent's ongoing experience of an anxiety disorder,[33] multiple forms of social and economic disadvantage[34] and major separation in the absence of maltreatment (e.g. in divorce proceedings)[35] have also been found to predict infant disorganized attachment behavior.
Researchers have found that over 60 hours per week of day-care predicts disorganized attachment in the infant independently of the caregiver's behavior during the time they do interact.
A meta-analysis of the first twenty-five randomised control trials of VIPP-SD found that the intervention led to more sensitive caregiver behaviour and less disorganized and more secure attachment relationships.
In research conducted in the early 1980s with parents from a Berkeley sample, Main and colleagues found that transcribed responses to the AAI could be placed into one of three categories, named 'secure-autonomous', 'dismissing' and 'preoccupied'.
Interviews categorised as preoccupied are characterised by angry, vague, confused, or fearful fixation on particular attachment relationships or experiences.
[48] Main has explained that "while the content of an individual's life history cannot change, it can be told or reconstructed in many differing ways".
Other speakers exhibited lapses in discourse, suddenly moving into speech that was excessively detailed, eulogistic in style or that involved prolonged and unacknowledged silences.
[53] A 'Cannot Classify' category has also been delineated by Hesse and Main which is used to describe interviews in which no single predominant attachment state of mind can be identified.
[57] Unresolved responses to the AAI have been found associated with frightening, frightened or dissociative parental behaviour[58] but it has also been found that only a small part of the association between unresolved states of mind and disorganized infant attachment can be explained by the mediation of anomalous parental behavior, indicating that other as yet unknown factors must also be involved.
"[61] She has highlighted that a variety of favourable and unfavourable experiences may alter a child's developmental pathway and hence their state of mind with respect to attachment.
[62] Mary Main has more than 40 published journal articles and book chapters and has over 25,000 google scholar citations (as of January 2015).