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Evidence of Physical Plasticity in Humans

  • R. Grant Steen
Chapter
Part of the The Springer Series on Human Exceptionality book series (SSHE)

Abstract

There is overwhelming evidence that human IQ is increasing at an astonishing rate of about 1 point every 2 years. This rapid rate of IQ change cannot be explained as a trivial artifact, such as a flaw in the tests or a change in the way that the tests are used. Neither can this rapid rate of change be explained by evolution, a process that is inexorable but majestic in tempo. Rising IQ is also not a result of accelerated child development, since the rate of child development may not be changing and is certainly not changing fast enough to explain the Flynn effect. And clearly the social environment – the supportive matrix of interactions provided by family – is unlikely to be improving at a rate that could power a 1% increase in IQ every 2 years; in fact, many critics argue that the family environment has been getting worse for years. Thus, the only remaining possibility would seem to be that the “non-social environment” is changing, in ways that foster intellectual performance among children. Clearly, a healthy child with better nutrition and more energy, a child with fewer school days lost to chronic illness, a child freed from the burden of hunger or homelessness, a child who has not been exposed to alcohol in utero or lead as an infant, a child immunized against the scourges of polio, influenza, hepatitis, and whooping cough, will be better able to shine on an IQ test. Yet it may be very hard for some people to accept that something as trivial as a vaccination program or a reduction in environmental lead can have an effect on human IQ. At issue, perhaps, is a sense that the brain determines who we are and that the essence of our being should not be so vulnerable to environmental insult; we would like to think that we are less susceptible to the sheer randomness of life. Perhaps, because each person is largely unaware of how the medical environment has impacted them, we are reluctant to credit that it can affect anyone else either. Or perhaps it is ingrained to consider the environment as being comprised entirely of the social network that surrounds us, so that it seems misguided to grant importance to a bacterium or a brief exposure to toxin.

Keywords

Medical Environment Early Life Stress Secular Change Cranial Vault Head Shape 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Springer Science+Business Media, LLC 2010

Authors and Affiliations

  1. 1.Medical Communications Consultants, LLCChapel HillUSA

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