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Neurologic state transitions in the eye and brain: Kinetics of loss and recovery of vision and consciousness

Published online by Cambridge University Press:  08 June 2015

TYP WHINNERY  and
ESTRELLA M. FORSTER
TYP WHINNERY*
Affiliation:
Oklahoma City, Oklahoma 73142
ESTRELLA M. FORSTER
Affiliation:
Mustang, Oklahoma 73064
*
*Address correspondence to: Typ Whinnery, P. O. Box 720753, Oklahoma City, OK 73172. E-mail: chance-whinnery@ouhsc.edu
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Abstract

Visual alterations, peripheral light loss (PLL) and blackout (BO), are components of acceleration (+Gz) induced loss of consciousness (LOC) and recovery of consciousness (ROC). The kinetics of loss of vision (LOV) and recovery of vision (ROV) were determined utilizing ocular pressure induced retinal ischemia and compared to the kinetics of LOC and ROC resulting from +Gz-induced cephalic nervous system (CPNS) ischemia. The time from self-induced retinal ischemia in completely healthy subjects (N = 104) to the onset of PLL and complete BO was measured. The time from release of ocular pressure, with return of normal retinal circulation, to the time for complete recovery of visual fields was also measured. The kinetics of pressure induced LOV and ROV was compared with previously developed kinetics of +Gz-induced LOC and ROC focusing on the rapid onset, vertical arm, of the +Gz-induced LOC and ROC curves. The time from onset of increased ocular pressure, immediately inducing retinal ischemia, to PLL was 5.04 s with the time to BO being 8.73 s. Complete recovery of the visual field from BO following release of ocular pressure, immediately abolishing retinal ischemia, was 2.74 s. These results confirm experimental findings that visual loss is frequently not experienced prior to LOC during exposure to rapid onset, high levels of +Gz-stress above tolerance. Offset of pressure induced retinal ischemia to ROV was 2.74 s, while the time from offset of +Gz-induced CPNS ischemia to ROC was 5.29 s. Recovery of retinal function would be predicted to be complete before consciousness is regained following +Gz-induced LOC. Ischemia onset time normalization in neurologic tissues permits comparison between different stress-induced times to altered function. The +Gz-time tolerance curves for LOV and LOC provide comparison and integration of neurologic state transition kinetics in the retina and CPNS.

Keywords

NeurophysiologyOphthalmologyVisionConsciousnessAcceleration (+Gz)
Type
Research Article
Information
Visual Neuroscience , Volume 32 , 2015 , E008
Copyright
Copyright © Cambridge University Press 2015 

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References

Acceleration (2002). Joint Aerospace Physiology Student Guide. CNATRA P-204 (Rev. 03-02) Naval Air Training Command; NAS Corpus Christi, Texas; Lesson JP (0)107:72–83.Google Scholar
Anderson, B. (1968). Ocular effects of changes in oxygen and carbon dioxide tension. Transactions of the American Ophthalmological Society 66, 423–474.Google ScholarPubMed
Andina, F. (1937). “Schwarzsehen” als ausdruck von blutdruckschwankungen bei sturzflugen. Schweizerische Medizinische Wochenschrift 67, 753–756.Google Scholar
Banks, R.D., Brinkley, J.W., Allnut, R. & Harding, R.M. (2008). Human response to acceleration. In Fundamentals of Aerospace Medicine (4th ed.), eds. Davis, J.R., Johnson, R., Stepanek, J. & Fogarty, J.A., pp. 83–109. Philadelphia: Lippincott Williams and Wilkins.Google Scholar
Burton, R.R. (1986). A conceptual model for predicting pilot group G tolerance for tactical fighter aircraft. Aviation, Space and Environmental Medicine 57, 733–744.Google Scholar
Burton, R.R. (2000a). Mathematical models for predicting G-level tolerances. Aviation, Space, and Environmental Medicine 71, 506–513.Google ScholarPubMed
Burton, R.R. (2000b). Mathematical models for predicting G-duration tolerances. Aviation, Space, and Environmental Medicine 71, 981–990.Google ScholarPubMed
Carlisle, R., Lanphier, E.H. & Rahn, H. (1964). Hyperbaric oxygen and persistence of vision in retinal ischemia. Journal of Applied Physiology 19, 914–918.CrossRefGoogle ScholarPubMed
Cochran, L.B., Gard, P.W. & Norsworthy, M.E. (1954). Variations in Human Tolerance to Positive Acceleration. Pensacola, Florida: US Naval School of Aviation Medicine. Research Report NM 001 059.02.10.CrossRefGoogle Scholar
Duane, T.D. (1953). Phase III. Preliminary Investigation into the Study of the Fundus Oculi of Human Subjects Under Positive Acceleration. Johnsville, PA: Naval Air Development Center. Report No. NM 001.060.12.01.Google Scholar
Duane, T.D. (1954). Observations on the fundus oculi during blackout. Archives of Ophthalmology 51, 343–355.CrossRefGoogle ScholarPubMed
Duane, T.D. (1966). Experimental blackout and the visual system. Transactions of the American Ophthalmological Society 64, 488–542.Google ScholarPubMed
Duane, T.D. (1967). Experimental blackout and the visual system. Aerospace Medicine 38, 948–962.Google ScholarPubMed
Forster, E.M. & Whinnery, J.E. (1992). Statistical Analysis of the Human Strangulation Experiments: Comparison to +Gz-Induced Loss of Consciousness. Warminster, PA: Naval Air Warfare Center. Report No. NAWCADWAR-92026-80.Google Scholar
Gaton, D.D., Ehrenberg, M., Lusky, M., Wussuki-Lior, O., Dotan, G., Weinberger, D. & Snir, M. (2010). Effect of repeated applanation tonometry on the accuracy of intraocular pressure measurements. Current Eye Research 35, 475–479.CrossRefGoogle ScholarPubMed
Gauer, O. & Henry, J.P. (1953). Physiology of flight. In Air Force Manual 160-30, Department of the Air Force, pp. 133–134. Washington, D.C: Government Printing Office.Google Scholar
Gauer, O.H. & Zuidema, G.D. (1961). The physiology of positive acceleration. In Gravitational Stress, Chapter 13 (1st ed.), eds. Gauer, O.H. & Zuidema, G.D., pp. 115–133. Boston: Little, Brown and Company.Google Scholar
Gillingham, K.K. (1988). High-G stress and orientational stress: Physiologic effects of aerial maneuvering. Aviation, Space, and Environmental Medicine 59(Suppl. 11), Al0–A20.Google ScholarPubMed
Gillingham, K.K. & Fosdick, J.P. (1988). High-G training for fighter aircrew. Aviation, Space, and Environmental Medicine 59, 12–19.Google ScholarPubMed
Green, N.D.C. (2006). Effects of long-duration acceleration. In Ernsting’s Aviation Medicine (4th ed.), eds. Rainford, D.J. & Gradwell, D.P., pp. 137–158. London: Oxford University Press.CrossRefGoogle Scholar
Ham, G.C. (1943). The effects of centrifugal acceleration on living organisms. War Medicine (Chicago) 3, 30–56.Google Scholar
Hickam, J.B. & Frayser, R. (1966). Studies of the retinal circulation in man. Circulation 33, 302–316.CrossRefGoogle ScholarPubMed
Howard, P. (1965). The physiology of positive acceleration. In A Textbook of Aviation Physiology (1st ed.), ed. Gillies, J.A., pp. 551–687. London: Pergamon Press.Google Scholar
Jorge, J., Ramoa-Marques, R., Lourenco, A., Silva, S., Nascimento, S., Queiros, A. & Gonzalez-Meijome, J.M. (2010). IOP variations in the sitting and supine positions. Journal of Glaucoma 19, 609–612.CrossRefGoogle ScholarPubMed
Klarica, M., Radoš, M., Erceg, G., Petošić, A., Jurjević, I. & Oreškovic, D. (2014). The influence of body position on cerebrospinal fluid pressure gradient and movement in cats with normal and impaired craniospinal communication. PLoS ONE 9(4), e95229.CrossRefGoogle ScholarPubMed
Krediet, C.T.P., Parry, S.W., Jardine, D.L., Benditt, D.G., Brignole, M. & Wieling, W. (2011). The history of diagnosing carotid sinus hypersensitivity: Why are the current criteria too sensitive? Europace 13, 14–22.CrossRefGoogle ScholarPubMed
Lambert, E.H. (1945). The physiologic basis of “blackout” as it occurs in aviators. Federation Proceedings 4, 43.Google Scholar
Lambert, E.H. & Bjurstedt, H. (1952). Effect of variations of oxygen and carbon dioxide tensions on latency of blackout produced by pressure on the eyeball. Federation Proceedings 11, 87–88.Google Scholar
Lambert, E.H. & Wood, E.H. (1946). The problem of blackout and unconsciousness in aviators. Medical Clinics of North America 30, 833–844.CrossRefGoogle ScholarPubMed
Lee, J.Y., Yoo, C., Jung, J.H., Hwang, Y.H. & Kim, Y.Y. (2012). The effect of lateral decubitus position on intraocular pressure in healthy young subjects. Acta Ophthalmologica 90, e68–e72.CrossRefGoogle ScholarPubMed
Lewis, D.H. (1955). An analysis of some current methods of G-protection. Aviation Medicine 26, 479–485.Google ScholarPubMed
Lindberg, E.F. & Wood, E.H. (1963). Acceleration. In Physiology of Man in Space, ed. Brown, J.H.U., pp. 61–111. New York: Academic Press.CrossRefGoogle Scholar
Magnaes, B. (1976). Body position and cerebrospinal fluid pressure. Part 1: Clinical studies on the effect of rapid postural changes. Journal of Neurosurgery 44, 687–697.CrossRefGoogle ScholarPubMed
Martin, E.E. & Henry, J.P. (1951a). The effects of time and temperature upon tolerance to positive acceleration. Journal of Aviation Medicine 22, 382–390.Google ScholarPubMed
Martin, E.E. & Henry, J.P. (1951b). The effects of time and temperature upon tolerance to positive acceleration. Technical Data Digest 16, 19–23.Google Scholar
McGowan, D.G. (1997). “ALOC” – Almost loss of consciousness and its importance to fighter aviation. [Abstract]. Aviation, Space and Environmental Medicine 68, 632.Google Scholar
Meyer, A. (2009). Transient loss of consciousness 1: Causes and impact of misdiagnosis. Nursing Times 105, 16–19.Google ScholarPubMed
Middlemore, R. (1835). Treatise on the Diseases of the Eye and its Appendages, Vol. II. London: Longman.Google Scholar
Mitchell, J.R., Roach, D.E., Tyberg, J.V., Belenkie, I. & Sheldon, R.S. (2012). Mechanism of loss of consciousness during vascular neck restraint. Journal of Applied Physiology 112, 396–402.CrossRefGoogle ScholarPubMed
Morrissette, K.L. & McGowan, D.G. (2000). Further support for the concept of a G-LOC syndrome: A survey of military high-performance aviators. Aviation, Space and Environmental Medicine 71, 496–500.Google ScholarPubMed
Murgatroyd, H. & Bembridge, J. (2008). Intraocular pressure. Continuing Education in Anaesthesia, Critical Care & Pain 8, 100–103.CrossRefGoogle Scholar
Palena, P.V., Jaeger, E.A., Behrendt, T. & Duane, T.D. (1970). Quantitative effect of increased intraocular pressure on blackout. Archives of Ophthalmology 83, 84–88.CrossRefGoogle ScholarPubMed
Reay, D.T. & Holloway, G.A. (1982). Changes in carotid blood flow produced by neck compression. American Journal of Forensic Medicine and Pathology 3, 199–202.CrossRefGoogle ScholarPubMed
Rossen, R., Kabat, H. & Anderson, J.P. (1943). Acute arrest of cerebral circulation in man. Archives of Neurology and Psychiatry 50, 510–528.Google Scholar
Ryoo, H.C., Sun, H.H., Shender, B.S. & Hrebien, L. (2004). Consciousness monitoring using near-infrared spectroscopy (NIRS) during high +Gz exposures. Medical Engineering & Physics 26, 745–753.CrossRefGoogle ScholarPubMed
Shender, B.S., Forster, E.M., Hrebien, L., Ryoo, H.C. & Cammarota, J.P. Jr. (2003). Acceleration-induced near-loss of consciousness: The “A-LOC”syndrome. Aviation, Space, and Environmental Medicine 74, 1021–1028.Google ScholarPubMed
Stewart, W.K. (1952). XVII. The physiological effects of gravity. Lectures on the Scientific Basis of Medicine 2, 334–342.Google Scholar
Stoll, A.M. (1956). Human tolerance to positive G as determined by physiological endpoints. Aviation Medicine 27, 356–367.Google Scholar
Toole, J.F. (1990). Applied physiology of the cerebral circulation. In Cerebrovascular Disorders, Chapter 2 (4th ed.), pp. 28–49. New York, NY: Raven Press.Google Scholar
Wieling, W., Krediet, C.T., Solari, D., de Lange, F.J., van Dijk, N., Thijs, R.D., van Dijk, J.G., Brignole, M. & Jardine, D.L. (2013). At the heart of the arterial baroreflex: A physiological basis for a new classification of carotid sinus hypersensitivity. Journal of Internal Medicine 273, 345–358.CrossRefGoogle ScholarPubMed
Vieira, G.M., Oliveira, H.D., De Andrade, D.T., Bottaro, M. & Ritch, R. (2006). Intraocular pressure variation during weight lifting. Archives of Ophthalmology 124, 1251–1254.CrossRefGoogle ScholarPubMed
Whinnery, J.E. (1979). Technique for simulating G-induced tunnel vision. Aviation, Space, and Environmental Medicine 50, 1076.Google ScholarPubMed
Whinnery, J.E. (1990). The G-LOC Syndrome. Warminster, PA: Naval Air Development Center. Report No. NADC-91042-60.Google Scholar
Whinnery, J.E. & Whinnery, A.M. (1990). Acceleration-induced loss of consciousness. A review of 500 episodes. Archives of Neurology 47, 764–776.CrossRefGoogle ScholarPubMed
Whinnery, T. & Forster, E.M. (2013). The +Gz-induced loss of consciousness curve. Extreme Physiology and Medicine 2, 19.CrossRefGoogle ScholarPubMed
Whinnery, T., Forster, E.M. & Rogers, P.B. (2014). The +Gz-recovery of consciousness curve. Extreme Physiology and Medicine 3, 9.CrossRefGoogle ScholarPubMed
White, W.J. (1961). Visual performance under gravitational stress. In Gravitational Stress, Chapter 11 (1st ed.), eds. Gauer, O.H. & Zuidema, G.D., pp. 70–79. Boston: Little, Brown and Company.Google Scholar
Wong-Riley, M.T.T. (2010). Energy metabolism of the visual system. Eye Brain 2, 99–116.CrossRefGoogle ScholarPubMed
Wood, E.H., Lambert, E.H., Baldes, E.J. & Code, C.F. (1946). Effects of acceleration in relation to aviation. Federation Proceedings 5, 327–344.Google ScholarPubMed
Woodrow, A.D. & Webb, J.T. (2011). Handbook of Aerospace and Operational Physiology. AFRL-SA-WP-SR-2011-0003. Air Force Research Laboratory 711th Human Performance Wing; School of Aerospace Medicine; Aerospace Medicine Education, Chapter 7.2.Google Scholar