However, some studies have shown that lack of maternal sensitivity can result in an infant displaying insecure attachment behaviours. A longitudinal study (same subjects studied over a period of time) on the impact of post-natal depression on infants was conducted by Murray (1992) and she found that by 18 months of age, the infants with depressed mothers were much more likely to be assessed as insecurely attached. Murray had videotaped interactions between these mothers and their infants over the 18-month period and found that these mothers seemed more preoccupied with their own thoughts and were not therefore responsive to the infants. These infants were also more often described as having behavioural problems. This study supports the views of Bowlby and Ainsworth that the primary caregiver should be available and responsive to the infant. Bowlby also believed that infants bond with just one mother figure, a concept called monotropism but perhaps, especially when the mother is depressed, the infant would benefit from attachments to other caregivers.
Bowlby's original Maternal Deprivation hypothesis was formed in light of several different sources of evidence, one of which was based on his own observation that around 9 months of age, infants display separation protest and fear of strangers. This has been observed in the 'Strange Situation' experiment, where typically the infant will not be comforted by the stranger in the playroom after the mother has left. Bowlby interpreted his observations to mean that the avoidance of strangers would prevent the infant from forming further attachments. Recent research has shown that infants can form more than one attachment although there is a limit to the number of these attachments and it is still important that the primary caregivers are sensitive to the infants needs.
Lewis (1986) found that fathers, if sensitively attuned to the infant could form an attachment with them.
The changing role of fathers is discussed on the audio-cassette band 'Fathering' where 'New Men' are now said to bond with their children rather than just provide financial security for them as in the past. Dr. Charlie Lewis suggests that this is nothing to do with the concept of the 'New Man' but is a result of fathers having more time to spend with their offspring because of unemployment and changing work patterns which allow for shared childcare between parents. But, as Dr Margaret O'Brien points out, the mother often shares a more intimate relationship with the newborn, as interaction with the infant can be quite intense during the months of breastfeeding. This relegates the attachment of the father to one of a supporting nature. Often where day-care is established for the infant, it will be the mother who makes arrangements to take and collect the infant and to be available during any periods of sickness.
Dr Charlie Lewis also pointed out on the tape, that many children are brought up in single-parent families without ill-effect, so perhaps fathers are not strictly necessary as long as the infant has one or two primary caregivers who are responsive and available. This idea is supported by the work of Wallerstein & Kelley (1980) who found that in cases of divorce, the children were least affected where grandparents were available to sensitively support the children throughout the experience. The concept of monotropism then, is gradually being replaced by the idea that infants will thrive where there is a strong social network supporting the child and where attachment is possible with one or two caregivers.
The maternal deprivation hypothesis was took account of studies of children who had experienced early childcare in institutions. One such study was conducted by Goldfarb (1947) who concluded that children who had been separated from their mothers before age 9 months and remained in care until age 3 ½, suffered retardation to their social, emotional and cognitive development. Bowlby saw these adverse effects as being due to the separation from the mother figure. Modern research has lead to a different interpretation of these studies. Orphanages in the 1940's were devoid of any stimulation for the infants which would account for the lack of cognitive development. Further studies by Tizard et al. (1975,1978) found that modern institutions providing a stimulating environment produce no adverse effects on children’s cognitive development. However there was still evidence of a lack of social and emotional development which was interpreted as being due to the high turnover of staff. Just as in Goldfarb’s day, the institutionalised infants suffered from too many caregivers resulting in a lack of bonding with any of them.
Another influential experiment (1969) by Harlow & Harlow showed that rhesus monkeys who had been separated from their mothers and reared in isolation became either withdrawn or aggressive and disturbed. It was concluded that if the separation continued beyond 3 months the effects were irreversible. This confirmed Bowlby's belief that separation from the maternal figure can result in delinquency, but subsequent research in 1972 by Suomi & Harlow found that although isolated monkeys tended to be attacked by other adult monkeys, when placed with other normally reared 3 month old monkeys they were able to overcome their depression and eventually gain social and emotional competence. Attachments then, seem to be important between siblings and peers as well as with the infant’s parents. The maternal deprivation hypothesis then, in the light of recent research, seems to be too narrow in it's focus on the maternal figure.
Bowlby was also influenced by the films of hospitalised children created by the Robertson’s (1967 - 1973), which highlighted the protest, despair and denial displayed, by these children. While these films served to improve the visiting arrangements at hospitals to alleviate the distress of the children it also reinforced the view that separation from the mother is psychologically damaging to the child. It is now recognised that it was not just the separation, but also the strange environment, the uniforms, the unpleasant medical procedures and lack of familiar/kind faces which resulted in distress. As Rutter (1981) suggested, separation from the primary caregiver is possible if handled sensitively.
Unfortunately, not all mothers find the maternal role satisfying; being constantly available and responsive to an infant can result in boredom, loss of self-esteem and even depression, especially in women who have taken a break from a satisfying career. A study by Boulton (1983) found that nearly half of the women in his sample felt that parenting was unfulfilling. Perhaps in these cases, it would be better for both the infant and the mother if both parents worked part-time and shared the childcare, or used another family member as a caregiver to the child. The issue of day-care is a complex one, seeming to favour environments where the adult to infant ratio is low enabling the infant to form an attachment to a caregiver (the Thomas Coram research unit study (Melhuish et al 1990)). Professor Melhuish has identified the features of high quality day-care as being the consistent supply of high quality communication, responsiveness and affection (T.V. program 'Attachment'). He states that where this quality of day-care is provided, no difference is found between the quality of attachment displayed by day-care children and that of home care children.
This finding represents a substantial modification to Bowlby's original recommendation. In 1966, the ethologist Konrad Lorenz elaborated his work on imprinting to include a critical period during which imprinting occurs. Bowlby was influenced by this work and suggested that humans have a critical period between the ages of 6 months and 3 years of age during which time the infant needs continuous care from the mother figure. This suggestion reinforced the view that mothers should stay at home with their pre-school age children. Bowlby's recommendation now seems too restrictive, as modern research is indicating that child day-care can be a positive experience for the infant.
One aspect of Bowlby's work which has not been modified but has provided the basis for further research is the concept of the internal working model. Bowlby suggested that the infant forms a mental representation of their relationship with their primary caregiver which persists throughout life. Work has been done using Mary Main's AAI (Adult Attachment Interview) to ascertain the quality of the relationship in the adult. It is widely believed that the quality of early attachment relationships affects the way we form later relationships and the quality of parenting skills. Research is currently investigating ways of intervening where there is risk of insecure attachment by modifying the adult internal working model.
Bowlby's work then has provided a good foundation for further research; the strange situation technique was based on Bowlby's theory of attachment and is still widely used today in assessing the quality of attachments. The concept of the internal working model is also still useful and has provided a way of approaching the improvement of parenting skills. Modern research has, however, largely rendered the maternal deprivation hypothesis redundant, along with the message that mothers should stay at home to raise their children.
