Chapter 6: The Staying Power of the Brain

1. Global Ageing. The Economist 2014;411(8884):13. Demography, growth and inequality. The Economist 2014;411(8884):23-5.
2. Butler RN, Miller RA, Perry D, et al. New model of health promotion and disease prevention for the 21st century BMJ 2008;337:149-50. Kiraly SJ. Mental health promotion for seniors. BC Medical Journal 2011;53(7):336-40.
3. Poon LW, Martin P, et al. The influence of cognitive resources on adaptation and old age. Int J Aging Hum Dev 1992;34(1):31-46. The Georgia Centenarian Study reported on 165 individuals between 60 and 100 years old: (Accessed on December 12, 2014)
4-5. Cone C. Theory of Cell Division. Chem Eng News 1970;48(14):7-8. Cone CD.(Sr) “Control of Cell Division by the Electrical Voltage of the Surface Membrane”, San Antonio, Texas : Proceedings of the Twelfth Annual Science Writers’ Seminar of the American Cancer Society, March, 1970. Cone CD (Jr), Cone CM. Induction of mitosis in mature neurons in central nervous system by sustained depolarization. Science 1976;192(4235):155–158.
6. Zimmer C. 100 Trillion Conections. Scientific American 2011;January:pp.59-63. The Brain. Winter 2009. pp. 88. In the 1970s the brain was considered to have at least 10 billion (1010) neurons. The number peaked around age 25. It dropped by 6% in an average lifetime. The possible interconnections, based on those figures was calculated to be an astounding 10801, an unimaginably and unmanageably large number. It is a number greater than the number of particles in the universe. Just for comparison, the number of particles in the observable universe has been estimated at 1080. The number of snowflakes that have ever fallen on earth is estimated at 1035. (Those estimates were from 1991)
7. Mathematicians who can calculate combinations, the different possible arrangements in a set, tell us that the number if neuronal combinations could be as high as 10 to the 100 trillionth power. That is 10100,000,000,000,000 (10 with a trillion zeros after it).
8. Eriksson PS, Perfilieva E, Bjork-Eriksson T, et al. Neurogenesis in the adult human hippocampus. Nature medicine 1998;4(11):1313-17. During neurogenesis some brain cells can give birth to new ones – entirely new brain cells. It was not until 1998 that this was conclusively demonstrated in humans. Kempermann G, Gage FH. New nerve cells for the adult brain. The Hidden Mind. Scientific American 1999;May:pp.38-44.
9-10. Pruning – Jay Giedd and colleagues (National Institutes of Health and Montreal Neurological Institute. Also, Nature, Volume 404, March 9, 2000. Jay Giedd: Kays JL, Hurley RA, Taber KH. The Dynamic Brain: Neuroplasticity and Mental Health. The Journal of Neuropsychiatry and Clinical Neurosciences 2012;24(2):118-124. Also see work of Elizabeth Sowell, Professor of Pediatrics, University of Southern California (neuroimaging, developmental cognitive neuroscience, brain development) (Accessed on December 13, 2014)
11. Diamond MC, Scheibel AB, Murphy GM, Harvey T. On the Brain of a Scientist: Albert Einstein. Experimental Neurology 1985;88:198-204.
12. Sachdev PS, Valenzuela M. Brain and Cognitive Reserve. Editorial. Am J Geriatr Psychaitry 2009;17(3):175-77. Merrill DA, Small GW. Prevention in Psychiatry: Effects of Healthy Lifestyle on Cognition. Psychaitr Clin N Am 2011;34:249-261.
13. Comijs HC, Gerritsen L, Penninx BWJH, et al. The Association Between Serum Cortisol and Cognitive Decline in Older Persons. Am J Geratr Psychiatry 2010;18(1):42-56.
14. Delaunay F, Khan A, Cintra A, et al. Pancreatic b Cells Are Important Targets for the Diabetogenic Effects of Glucocorticoids. J Clin Invest 1997;100(8):2094-98. Couce M, Kane LA, O’Brien TD, et al. Treatment with growth hormone and dexamethasone in mice transgenic for human islet amyloid polypeptide causes islet amyloidosis and beta-cell dysfunction. Diabetes 1996;45(8):1094-101. Blondeau B, Lesage J, Czernichow P, et al. Glucocorticoids impair fetal b-cell development in rats. Am J Physiol Endocrinol Metab 2001;281:E592-E599. Ehrmann DA, Breda E, Corcoran MC, Cavaghan MK, et al. Impaired beta-cell compensation to dexamethasone-induced hyperglycemia in women with polycystic ovary syndrome. Am J Physiol Endocrinol Metab 2004;287(2):E241-6.

Additional Readings & Resources:
Wickelgren I. The Aging Brain: For the Cortex, Neuron Loss May Be Less Than Thought. Science 1996;273:48-50.
Kimura S. Brain tissue generated from embryo stem cells. Reported in: The Asahi Shimbun, November 7, 2008. pp.23. The team at Riken Center for Developmental Biology reported that self organizing, complex cortical brain tissue 2 mm in diameter was created from human embryonic stem cells (also in the journal Stem Cell).
Alleyne R. Fri Mar 4 2011, Page: B1 / Front, Section: Canada & World. By: Richard Alleyne. Dateline: LONDON. Source: Daily Telegraph: American researchers have turned stem cells derived from skin into neurons in the brain that are critical to memory retrieval but which are killed by the degenerative conditions “Now that we have learned how to make these cells, we can study them in a tissue culture dish and figure out what we can do to prevent them from dying,” said Dr. Jack Kessler, who led the study at Northwestern University in Chicago. Kessler’s team has successfully tested the neurons on mice. The research is published in the journal Stem Cells.
Pinel, J. Biopsychology: Hot Topics. Neurogenesis in the Adult Human Brain: (Accessed on December 13, 2014)


Reviewed on December 13, 2014