There are some criticisms of the ‘strange situation’ largely concerning its low ecological validity: Lamb suggests that the main problems with the experiment are that it is extremely artificial and fails to take the mother’s behaviour into account. Main et al (1985) suggested a fourth classification (Type D – insecure/disorganised infants) after finding that 13% of infants tested did not conform to either the A, B or C classifications set out by Ainsworth.
Main’s Type D infants displayed a diverse array of disorganised and disordered behaviour and failed to display a clear-cut strategy for dealing with stressful situations. Cross-cultural studies are helpful in determining universal traits and can also point to any culture specific aspects of testing situations thus providing useful evaluative material. 32 worldwide studies using the ‘strange situation’ with over 2000 infants carried out by Van Ijzendoom ; Kroonenberg (1985) came up with three major conclusions: firstly there are marked intra-cultural differences in distribution of the attachment Types A, B and C. Secondly, the overall distribution of attachment types was very close to Ainsworth’s standard (Type B 70%, Types A and B approximately 15% each), but even within the US there was a high variability between samples.
Van Ijzendoom ; Kroonenberg found a strong pattern of cross-cultural differences whereby Type B infants are universally the most common whereas Type A babies are more common than Type A in Western Europe and Type C are more common than Type A in Israel and Japan, indicating that cultural differences affect the way in which the ‘strange situation’ is interpreted by children, for instance, Japanese babies who are rarely separated from their mothers find her departure during the experiment more upsetting than majority of children from most of other cultures.
It is also worth mentioning ethical implications whilst evaluating Ainsworth’s experiment as it is designed to see how infants react to stress in the form of an unfamiliar physical environment, separation from their mother and contact with a stranger; however the experiment is adapted to the needs of each infant with certain stages being lengthened or shortened in order to avoid undue stress on the part of the infant.
Whereas Ainsworth’s work was mainly geared towards creating a methodical way of categorising attachment types, Bowlby’s approach was a lot more theoretical. Bowlby’s attachment theory was highly influenced by ethological theory (especially Lorenz’s theory of imprinting); in particular he emphasised the instinctive nature of attachment, including his theory of monotropy, and the existence of a critical period for attachment formation. Schaffer (1989) views Bowlby’s theory as ‘…the most comprehensive theoretical account of attachment formation.’ It has become the most widely used conceptual framework within which research on attachment has been conducted in recent years.
Bowlby views attachment behaviour as instinctive. Babies are born with a tendency to display proximity-ensuring behaviours such as smiling and crying, which are displayed towards the mother figure. Bowlby hypothesised that infants and mothers have evolved a biological need to stay in constant contact with each other and that attachment is an important survival mechanism protecting against predators by reducing the amount of time the infant spends separated from the mother.
Bowlby claimed that the infant displays a strong innate tendency to become attached to one particular individual, he termed this monotropy and asserted that it is normally, though not exclusively, an instinct geared towards the mother. This attachment is qualitatively different from any subsequent attachments; Bowlby argues that the attachment to the mother is of a different order altogether from other relationships.
Schaffer and Emerson (1964) carried out a study which produced results which directly conflict with Bowlby’s theory of Monotropy. During four-weekly visits to family homes during a baby’s first year with a follow up visit at 18 months, attachment was measured by the amount of protest the baby showed when separated from a familiar person. At about seven months, 29% had already formed several attachments simultaneously, by ten months 59% had developed more than one attachment and by 18 months, 87% had formed multiple attachments.
Although there was usually only one particularly strong attachment, only half of the 18-month-olds were principally attached to the mother. From Schaffer and Emerson’s study it can be concluded that infants form a hierarchy of attachments and that multiple attachments are the exception rather than the rule and the mother is not always or necessarily the main attachment figure.
The concept that there is a critical period for the formation of primary attachments is a view that was proposed by Bowlby, who suggested that children must form attachments before the age of two or else they would never recover. Rutter (1981) however, believes that although there is a sensitive period during which children are more likely to form primary attachments, recovery of maternal deprivation is possible over time. The onset of the sensitive period is determined by perceptual factors: the infant directs attachment behaviour directly once he has the ability to discriminate between people. The sensitive period is gradually brought to an end as the infant becomes increasingly wary of strangers.
The combined ideas of monotropy and the critical period led Bowlby to the formation of the Maternal Deprivation Hypothesis. Bowlby believed that the attachment to the mother could not be broken in the first few years of life without serious and permanent damage to social, emotional and intellectual development. Also, if an attachment that had already been formed was disrupted through separation from the mother figure there would be severe emotional effects on the infant for the duration of the separation, with a risk of permanent damage depending on the length of the separation. One problem with assessing Bowlby’s ideas about deprivation is that human deprivation can only be studied where it occurs naturally and deprivation is unlikely to be an isolated event so the separation from the mother will be the result of other factors, therefore the precise cause of an infant’s behaviour cannot be directly determined.
The short term affects of deprivation, occurring either immediately or over a short period of time after separation from the mother, follow a typical sequence. First the infant shows protest in the form of acute distress, then despair is displayed as general misery and apathy and finally detachment when the infant is no longer concerned by the parent’s absence. Research by Rutter has shown that there are a number of factors which effect the intensity of the separation anxiety expressed by infants. Firstly, distress on separation is greater in a strange environment (for instance admission to hospital) than in a familiar one, secondly a link with previous family life – either the presence of someone in the family or the continuity of the structure of family life with new people may reduce a child’s feelings of isolation – children accompanied by a sibling to a residential nursery showed significantly less distress than children attending alone (Heinicke ; Westheimer, 1967).
Long-term effects of maternal deprivation, which may occur several years after separation, include metal retardation and defects of personality or behaviour. Evidence for this conclusion comes mainly from studies of institutionalised children who Tizard showed to display retardation in language and cognition. However, there is evidence that when institutional care involves a good quality of stimulation, no intellectual impairment is found. Children with a large number of siblings have been shown to display poorer intellectual development than their contemporaries implying that parental attention and interaction is important in intellectual development which may be the element missing in institutions where there may be a large child to adult ratio. Alternatively it is possible that that lack of social stimulation could have an indirect influence on intellectual development for instance, depression resulting from emotional deprivation could lead to poor intellectual progress.
Evidence provided by Rutter suggests that infants institutionalised early are more likely to show subsequent personality problems that those institutionalised late and implying that that long-term problems are the result of failure to form an attachment rather than being due to subsequent attachment disruption. There appear to be long-term effects of early life experiences but problems appear to arise primarily as a result of a loss rather than a lack of normal family experience. Bowlby’s emphasis of the mother’s role in deprivation is perhaps a little extreme; problems of deprivation could be viewed as a result of social deprivation as a whole rather than as a direct result of separation from the mother.
Bowlby’s work shows the importance of the formation of secure attachments during the early stages of infancy whilst Ainsworth’s ‘strange situation’ allows an objective measure to be made of attachment types. This enables us to attempt to determine the factors which contribute to successful attachment formation, which can be argued to be paramount with regards to intellectual, social and emotional success later in life.
Both Ainsworth and Bowlby have their critics but are widely regarded to be the leading names in their field; the sheer number of replications of Ainsworth’s experiment speaks volumes about the confidence that other psychologists have in her procedures whilst Bowlby’s theory of attachment could be argued to be in need of revision, but on the other hand, Bowlby’s work, commissioned by the World Health Organisation, had an enormous impact in the history of social reform. Bowlby’s work has had an enormous impact on social work policy, legislation relating to children, psychology and psychiatry.