SAGE KE Bulletin Board

Linking Bionics with Reliability Theory on Aging

24 September 2004

Rainer Spiegel

Leonid Gavrilov’s and Natalia Gavrilova’s article “Why we fall apart“ (Sep 2004 IEEE Spectrum, 16-21) provides very interesting ideas on aging and technology by linking human aging to the reliability theory in engineering. The Gavrilov’s write that similar to technical equipment "we age because our makeup includes irreplaceable but redundant parts, many of which are defective, and we age as each of those parts inevitably stops working." The authors’ idea is that advances in regenerative medicine might help to replace failed organs such as lungs, kidneys and heart tissue. As a consequence, humans could expect to live longer. In this letter I would like to add to these ideas some thoughts about neurobiology, bionics and the immune system. As far as the nervous system is concerned, there is much greater plasticity in early childhood than in later periods of human life (e.g. Elman et al., 1996, Rethinking Innateness, Cambridge MA: MIT-Press), though it has recently been discovered that throughout our lives, a limited number of neurons continue to form. It remains an open question whether it will be possible to sufficiently repair damages to the brain in very high age. We also know that the functioning of our immune system decreases with growing age. On the other hand, the functioning of our immune system is not only dependent on genetic influences, but also on external factors such as our bio-psycho -social well-being (e.g. Ader & Cohen, 1993, Psychoneuroimmunology, Annual Review of Psychology, 44, 53-85; David Spiegel et al., 1989, Effect of psychosocial treatment on survival of patients with metastatic breast cancer, Lancet, ii: 888-891; David Spiegel, 1993, Living Beyond Limits: New Hope and Help for Facing Life-Threatening Illness, New York: Times Books). It is not difficult to deduce that the loss of vision, hearing and sensorimotor function will have adverse effects on people’s bio-psycho- social well-being, which is likely to have a negative impact on their immune system. Because a well-functioning immune system is associated with a longer life, one could imagine that recent advances in bionics have a positive effect on people’s life expectancy. These advances include technical devices that help restore lost vision, hearing and sensorimotor function, which could ultimately lead to a better quality of life. William Craelins’ article "The Bionic Man: Restoring Mobility" (Science, 2002, 295, 1018-1021) provides an overview on recent advances in this field, and Donald Kennedy’s editorial "Longevity, Quality, and the One-Hoss Shay" (Science, 2004, 305, 1369) is related to longevity in particular.

Science of Aging Knowledge Environment. ISSN 1539-6150