A mind free of nurture

A core question in the study of personality and intelligence is about the relative contribution of inherited traits and learned behaviours. How much nature vs how much nurture shapes the mind? This problem can be approached in several ways, including the study of monozygotic twins that have been reared apart, and adoption studies (e.g. comparing the IQ of the biological vs. the adoptive parents to assess genetic vs. environmental effects respectively). However, on rare occasions we get the opportunity to study extreme cases of how nature and nurture influences the human mind. Such occasions include children that have grown up without (or with very little) influence from other people.

Such stories are at the same time shockingly disturbing and at the same time truly amazing, and they provide us with insights into the development of the human mind. It has demonstrated, for example, how there is a critical period for language acquisition.

What happens to a mind that is deprived from cultural influence during childhood? This is the ultimate test of the nature-nurture debate. But it is also the ultimate non-ethical experiment. Nevertheless, on rare occasions science has been provided with cases where children have been abandoned or seriously socially deprived. We don’t have to go father than last week’s story about Natascha Kampusch, the now 18 year old woman who was kidnapped eight years ago and kept in a cramped, windowless underground bedroom during her captivity, and isolated from interactions with any other human beings. Kampusch still had interaction with her kidnapper, but she has spent her entire adolescence in social isolation, a period of development that involves the development of social skills and personality.

In Boston Review, Rebecca Saxe who is an MIT psychologist, has an excellent review of Encounters with Wild Children by Adriana S. Benzaquén. The book is about the history of scientific studies of “wild children”, or as the publisher write:

Since the early seventeenth century, stories of encounters with strange children in unusual circumstances have been recorded, circulated, and reproduced in Europe and North America not simply as myths, legends, or good tabloid copy but as occurrences deserving serious scrutiny by philosophers and scientists. “Wild children” were seen as privileged objects of knowledge, believed to hold answers to fundamental questions about the boundaries of the human, the character and significance of civilization, and the relation between nature and culture, heredity and environment.

The study of these “wild children” have thus been thought of as a genuine path to study the influence of culture (or, rather, lack thereof) on the developing mind. But as Benzaquèn argues, we should not give these studies this high rank. As Saxe writes:

But here’s the catch: the forbidden experiment may belong to a smaller group of experimental problems that persistently seem meaningful but are not. Intuitively, we expect that while human nature interacts with human society in a typical child’s development, the natural and the social are in principle independent and distinguishable. If this intuition is wrong, the forbidden experiment is incoherent. In fact, the social and the natural may be irretrievably entangled in development. In part this is because a social environment that includes other human beings is inevitably more natural for a human infant than any wholly artificial environment that could be constructed to replace it. Even the unfolding of innately determined human traits relies on a social environment. For example, virtually every human infant is exposed to a language and learns it; an infant who was never exposed to any language could not possibly speak one. Yet it is the children who do learn a language—through social interactions—who illustrate the natural human capacity.

So although we might be interested in the psychological profile and story that may eventually come from the Natascha Kampusch story, it should definitely be taken with more than a grain of salt.

-Thomas

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