At its base, traditional attachment theory makes the following prediction – take identical children and separate them at birth. One is brought up in a loving family where it forms stable attachments to its adopted or real parents. The other is less fortunate. It is moved through a children’s home, to foster parents, back into care and has no chance to enjoy a proper upbringing. Child one goes to a good school, child two goes to lots of bad schools. According to attachment theory we should see marked differences between the children once they grow into adults. But we don’t.
Even if no one has been cruel enough to do the experiment mentioned above, there have been hundreds of studies of identical twins separated at birth. The researchers were trying to establish how much their personalities and behaviour were affected by nature and how much by nurture. The answer was that identical twins showed a correlation with each other of about 50%. But this figure was almost the same whether they were brought up together by their natural parents, brought up together by adopted parents or separated and brought up apart. Nurture seemed to play no part. Likewise, adopted children did not correlate to their adopted parents anymore than a stranger off the street would. There were some nurture effects while children were still growing up, but once they were adults, these disappeared.
The first person to try to make sense of these results (which were the opposite of what most researchers had expected), was Judith Rich Harris in her book The Nurture Assumption. She was not a psychologist, still less a geneticist and some felt her outsider-status gave them a license to ignore or insult her. Contrary to popular belief, Harris did believe in nurture, but from peers rather than parents. Since attachment theory is generic enough to handle peer-to-peer relationships, some attachment theorists responded to Harris’s criticisms of family-based nurturing effects by shifting their attention from the parlour to the school yard.
The trouble is that there is hardly any evidence for Harris’s peer pressure hypothesis and quite a lot against it. For a start, it is, at first sight, unlikely that parents could have practically no effect and other children such a lot. Work comparing children sent to nursery at six months and those kept at home has found some evidence that the former are more confident and aggressive, but this wears off before they grow up. The Chicago work on school places I referred to a few posts ago suggests it doesn’t matter which school you went to, although this was based on academic results rather than personality. More work is required and we are still hamstrung by having no reliable way to measure intelligence, but things are looking pretty grim for the peer-to-peer hypothesis. The family hypothesis is already dead, if not buried. If peer pressure goes the same way, as seems very likely, there will be nothing left for attachment theory to attach itself to as far as long term outcomes are concerned.
Of course, attachment theory still feels it has something to say about relationships. We are all happier in a stable unit than cast out on our own. Single people are sadder than married people, orphans are less happy than children with both parents. But I’m not sure that we need a special theory to tell us this or that attachment theory’s explanations rise much above the level of psychobabble.
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