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Brain Development and Increasing Intelligence

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

Abstract

In the past, it was essentially impossible to study brain changes in a healthy child because no means existed to examine the brain without doing at least some harm to the child. Brain surgery is only done as a last resort, when someone is desperately ill, hence, this option was ruled out as a way to understand the developing brain. Autopsy is permissible in a child who has died, but there is always a concern whether a child who has died is fundamentally different from a child who is well. Medical imaging could have been done, but medical imaging carried some risk for the person being imaged. Over 100 years ago, X-rays were discovered, so they could have been used to study the developing brain, but this was not done because of the risks from radiation; even low levels of radiation can be harmful to the growing brain [1]. More recently, computed tomography (CT) became available, which yields far more detailed images, but CT still requires radiation exposure, so the benefits of research do not outweigh the risks of harm [2]. Recent advances in medical imaging have reduced the radiation-related risk concerns, making it safe to study the developing brain. Using a method called magnetic resonance imaging or MRI, it is possible to visualize the brain at every phase of its growth, from the fetus to the fully adult, without exposing a person to harmful radiation. The MRI method is too complex to be explained in detail, but the images are simply maps of the distribution and abundance of water in brain tissue. Because the brain is soft tissue containing a great deal of water, these “water maps” form detailed and genuinely beautiful images that enable clinicians to visualize the brain with clear and compelling detail. Contrast between structures in the image is largely a function of the water content of brain tissue. Thus, a bright area in an image can reveal brain regions with a great deal of free water, such as the fluid-filled spaces within or around the brain. Conversely, dark areas in an image can reveal brain regions that have relatively little water content, such as the cortical gray matter. These images are so detailed and so faithful to brain anatomy that neuro­surgeons routinely use them while planning surgery.

Keywords

White Matter Gray Matter Gray Matter Volume Pubertal Timing White Matter Volume 
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.

References

  1. 1.
    Steen, R. G. (1996). DNA & Destiny: Nature and Nurture in Human Behavior. New York: Plenum. 259 pp.Google Scholar
  2. 2.
    Flynn, J. (1984). The mean IQ of Americans: Massive gains 1932 to 1978. Psychological Bulletin, 95, 29–51.CrossRefGoogle Scholar
  3. 3.
    Prifitera, A., Weiss, L. G., & Saklofske, D. H. (1998). The WISC-III in context. In A. Prifitera & D. Saklofske (Eds.), WISC-III Clinical Use and Interpretation: Scientist-Practitioner Perspectives (pp. 1–38). New York: Academic.CrossRefGoogle Scholar
  4. 4.
    Flynn, J. R. (1998). Israeli military IQ tests: Gender differences small; IQ gains large. Journal of Biosocial Science, 30, 541–553.CrossRefPubMedGoogle Scholar
  5. 5.
    Randhawa, B. S. (1980). Change in intelligence and academic skills of grades four and seven pupils over a twenty-year period. 22nd International Congress of Psychology. Leipzig, East Germany.Google Scholar
  6. 6.
    de Leeuw, J., & Meester, A. C. (1984). Over het intelligence-onderzoek bijde militaire keuringer vanaf 1925 tot heden [Intelligence-as tested at selections for the military service from 1925 to the present]. Mens en Maatschappij, 59, 5–26.Google Scholar
  7. 7.
    Rist, T. (1982). Det Intellektuelle Prestasjonsnivaet i Befolkningen Sett I lys av den Samfunns-Messige Utviklinga [The level of the intellectual performance of the population seen in the light of developments in the community]. Oslo, Norway: Norwegian Armed Forces Psychology Service.Google Scholar
  8. 8.
    Teasdale, T. W., & Owen, D. R. (2000). Forty-year secular trends in cognitive abilities. Intelligence, 28, 115–120.CrossRefGoogle Scholar
  9. 9.
    Bouvier, U. (1969). Evolution des cotes a quelques tests [Evolution of scores from several tests]. Brussels, Belgium: Belgian Armed Forces, Center for Research into Human Traits.Google Scholar
  10. 10.
    Elley, W. B. (1969). Changes in mental ability in New Zealand school-children. New Zealand Journal of Educational Studies, 4, 140–155.Google Scholar
  11. 11.
    Clarke, S. C. T., Nyberg, V., & Worth, W. H. (1978). Technical report on Edmonton Grade III achievement: 1956–1977 comparisons. Edmonton, Alberta: University of Alberta.Google Scholar
  12. 12.
    Uttl, B., & Van Alstine, C. L. (2003). Rising verbal intelligence scores: Implications for research and clinical practice. Psychology and Aging, 18, 616–621.CrossRefPubMedGoogle Scholar
  13. 13.
    Vroon, P. A., de Leeuw, J., & Meester, A. C. (1984). Correlations between the intelligence levels of fathers and sons. In J. R. Flynn (Ed.), Utrecht, The Netherlands: Department of Theoretical Psychology and History of Psychology.Google Scholar
  14. 14.
    Colom, R., & Garcia-Lopez, O. (2003). Secular gains in fluid intelligence: Evidence from the culture-fair intelligence test. Journal of Biosocial Science, 35, 33–39.CrossRefPubMedGoogle Scholar
  15. 15.
    Lynn, R., Hampson, S. L., & Mullineux, J. C. (1987). A long-term increase in the fluid intelligence of English children. Nature, 328, 797.CrossRefPubMedGoogle Scholar
  16. 16.
    Daley, T. C., et al. (2003). IQ on the rise: The Flynn effect in rural Kenyan children. Psychological Science, 14, 215–219.CrossRefPubMedGoogle Scholar
  17. 17.
    Fuggle, P. W., et al. (1992). Rising IQ scores in British children: Recent evidence. Journal of Child Psychology and Psychiatry, 33, 1241–1247.CrossRefPubMedGoogle Scholar
  18. 18.
    Girod, M., & Allaume, G. (1976). L’evolution du niveau intellectuel de la population francaise pendent le dernier quart de siecle [The evolution of the intellectual level of the French population during the last quarter century]. International Review of Applied Psychology, 25, 121–123.CrossRefGoogle Scholar
  19. 19.
    Steen, R. G. (2007). The Evolving Brain: The Known and the Unknown (p. 427). New York: Prometheus Books.Google Scholar
  20. 20.
    Gould, S. J. (1981). The Mismeasurement of Man. New York: W. W. Norton & Co. 352 pp.Google Scholar
  21. 21.
    Detterman, D. K., & Thompson, L. A. (1997). What is so special about special education? The American Psychologist, 52, 1082–1090.CrossRefPubMedGoogle Scholar
  22. 22.
    Brand, C. (1987). Intelligence testing: Bryter still and bryter? Nature, 328, 110.Google Scholar
  23. 23.
    Daley, T. C., et al. (2003). IQ on the rise: The Flynn effect in rural Kenyan children. Psychological Science, 14, 215–219.CrossRefPubMedGoogle Scholar
  24. 24.
    Steen, R. G. (1996). DNA & Destiny: Nature and Nurture in Human Behavior (p. 295). New York: Plenum.Google Scholar
  25. 25.
    Flynn, J. R. (1987). Massive IQ gains in 14 nations: What IQ tests really measure. Psychological Bulletin, 101, 171–191.CrossRefGoogle Scholar
  26. 26.
    Carpenter, P. A., Just, M. A., & Shell, P. (1990). What one intelligence test measures: A theoretical account of the processing in the Raven Progressive Matrices Test. Psychological Review, 97, 404–431.CrossRefPubMedGoogle Scholar
  27. 27.
    Duncan, J., & Owen, A. M. (2000). Common regions of the human frontal lobe recruited by diverse cognitive demands. Trends in Neurosciences, 23, 475–483.CrossRefPubMedGoogle Scholar
  28. 28.
    Flynn, J. R. (1998). Israeli military IQ tests: Gender differences small; IQ gains large. Journal of Biosocial Science, 30, 541–553.CrossRefPubMedGoogle Scholar
  29. 29.
    Teasdale, T. W., & Owen, D. R. (2000). Forty-year secular trends in cognitive abilities. Intelligence, 28, 115–120.CrossRefGoogle Scholar
  30. 30.
    Teasdale, T. W., & Owen, D. R. (1987). National secular trends in intelligence and education: A twenty-year cross-sectional study. Nature, 325, 119–121.CrossRefGoogle Scholar
  31. 31.
    Johnson, S. (2005). Eveything Bad is Good for You. New York: Penguin GroupGoogle Scholar
  32. 32.
    Pullman, H., Allik, J., & Lynn, R. (2004). The growth of IQ among Estonian schoolchildren from ages 7 to 19. Journal of Biosocial Science, 36, 735–740.CrossRefGoogle Scholar
  33. 33.
    Slyper, A. H. (2006). The pubertal timing controversy in the USA, and a review of possible causative factors for the advance in timing of onset of puberty. Clinical Endocrinology, 65, 1–8.CrossRefPubMedGoogle Scholar
  34. 34.
    Herman-Giddens, M. E., et al. (1997). Secondary sexual characteristics and menses in young girls seen in office practice: a study from the Pediatric Research in Office Settings Network. Pediatrics, 99, 505–512.CrossRefPubMedGoogle Scholar
  35. 35.
    Kaplowitz, P. B., Slora, E. J., Wasserman, R. C., Pedlow, S. E., & Herman-Giddens, M. E. (2001). Earlier onset of puberty in girls: relation to increased body mass index and race. Pediatrics, 108, 347–353.CrossRefPubMedGoogle Scholar
  36. 36.
    Sun, S. S., et al. (2002). National estimates of the timing of sexual maturation and racial differences among US children. Pediatrics, 110, 911–919.CrossRefPubMedGoogle Scholar

Copyright information

© Springer Science+Business Media, LLC 2010

Authors and Affiliations

  1. 1.Medical Communications Consultants, LLCChapel HillUSA

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