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Real-time recording of neuropsychophysiological parameters during 50 Hz magnetic field exposure

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Abstract

In order to assess the possible effects of occupational levels of 50 Hz magnetic fields (MF) on human performance it is preferable to monitor performance during rather than subsequent to MF exposure. We previously reported studies of heart rate and cognitive behaviour where the issue of contamination was not a serious one. Our present study involves electrophysiological measures, which have a greater capacity to identify the effects and assist in localising them. The contamination of EEG signal by the MF exposure is clearly a problem in this type of study. Previous investigators have not reported these types of measurement concurrent with MF exposure due to the contamination difficulty; but this paper reports means of accomplishing this. Overall a combination of 12 methods for reducing pickup were employed. These were: 1) Distancing recording instruments from the MF source; 2) Shielding the devices and wiring; 3) Appropriate choice of cables; 4) Grounding the instrumentation; 5) Orientation of conduits; 6) Isolation of electrical mains power supplies; 7) Balancing the input impedances; 8) Applying a driven shield technique; 9) Improved electronics design incorporating pre-amplification and circuit impedance level control; 10) Analogue filtering; 11) Signal Averaging; and 12) Post acquisition digital filtering using frequency and time domain techniques.

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References

  1. Keetley, V., Wood, A. W., Sadafi, H. A. and Stough, C. K. K.,Neurological sequelae of 50Hz magnetic fields, Int J Radiation Biol., 77(6): 735–742, 2001.

    Article  CAS  Google Scholar 

  2. Sadafi, H. A., MAppSc Thesis,Human physiological effects of power frequency magnetic fields, School of Biophysics and Electrical Engineering, Swinburne University of Technology, 1993.

  3. Kazantzis, K., Podd, J. V. and Whittington, C. J.,Acute effects of 50 Hz, 100 μT magnetic field exposure on visual duration discrimination at two different times of the day, Bioelectromagnetics, 19: 310–317, 1998.

    Article  CAS  PubMed  Google Scholar 

  4. Graham, C., Cook, M. R., Cohen, H. D., Riffle, D. W., Hoffman, S. J. and Gerkovich, M. M.,Human exposure to 60 Hz magnetic fields: neurophysiological effects, Int J Psychophysiol., 33: 169–175, 1999.

    Article  CAS  PubMed  Google Scholar 

  5. Merritt, R., Purcell, C. and Stronik, G.,Uniform magnetic field produced by three, four and five square coils, Rev Sci Instrum., 54 (7 July), 1983.

  6. Sadafi, H. A., PhD Thesis,Human Brain Effects of 50 Hz Electricity Power Frequency Magnetic Fields with special emphasis on assessment of neurophysiological and cognitive behavioural measures during magnetic field exposure, School of Biophysics and Electrical Engineering, Swinburne University of Technology, 2003.

  7. AS3005,Electrical installations — Patient treatment areas of hospitals and medical and dental practices, Australian Standards, 1985.

  8. AS3200, AS3200 2.1: Approval and test specification — Medical electrical equipment: General requirements for safety collateral standard electromagnetic compatibility requirements and tests, Australian Standards, 1995.

  9. IEC601-2-26,Medical electronic equipment, Part 2: Particular requirements for the safety of electroencephalographs, 1993.

  10. EN60601-1,Medical electronic equipment — Part 1: General requirements for safety, European Standards, 1992.

  11. Preece, A. W., Wesnes, K. A. and Iwi, G. R.,The effect of a 50 Hz magnetic field on cognitive function in humans, Int J Radiat Biol., 74: 463–470, 1998.

    Article  CAS  PubMed  Google Scholar 

  12. Hyne, J.,Electromagnetic interference control in buildings, 2nd ed. Paradigm Press, Australia, 2002.

    Google Scholar 

  13. Berger, H.,Uber das elektrenkephalogramm des menchen, Arch Psychiat Nervenheik., 87: 527–570, 1929.

    Article  Google Scholar 

  14. Duffy, F. H., Jones, K., Bartels, P., Albert, M., McAnulty, G. B. and Als, H.,Quantified neurophysiology with mapping: Statistical influence, exploratory and confirmatory data analysis, Brain Topogr., 3: 3–12, 1990.

    Article  CAS  PubMed  Google Scholar 

  15. Siberstein, R. B. and Cadusch, P. J.,Measurement processes and spatial principal component analysis., Brain Topogr., 4: 267–276, 1992.

    Article  Google Scholar 

  16. Jung, T. P., Humphries, C., Lee, T. W., Makeig, S., McKeown, M.J., Iragui, V. and Sejnowski, T.J.,Removing electroencephalographic artefacts: Comparison between ICA and PCA, Neural Networks for Signal Processing, VIII: 68-72, 1998.

  17. Maskell, S. J.,RF susceptibility of an EEG and considerations for attenuating RFI in hospitals, IEEE Trans Ind Appl., IA-21: 876–881, 1985.

    Article  Google Scholar 

  18. Stecker, M. M. and Patterson, T.,Strategies for minimizing 60 Hz pick up during evoked potential recording, Electroencephal Clin Neurophysiolo., 100: 370–373, 1996.

    Article  CAS  Google Scholar 

  19. Winter, B. B. and Webster, J. G.,Reduction of interference due to common mode voltage in biopotential amplifiers, IEEE Trans Biomed Eng., BME-30: 58–61, 1983.

    Article  CAS  PubMed  Google Scholar 

  20. Pallás-Areny, R.,Interference-rejection characteristics of biopotential amplifiers: A comparative analysis, IEEE Trans Biomed Eng., BME-35: 953–959, 1988.

    Article  PubMed  Google Scholar 

  21. Metting, V.A.C., Peper, A. and Grimbergen, C.A.,High quality recording of bioelectric events, Part. 1: Interference reduction, theory and practice, 1990.

  22. Wood, D. E., Ewins, D. J. and Balachandran, W.,Comparative analysis of power-line interference between two- and threeelectrode biopotential amplifiers, Med Biol Eng Comput., 33: 63–68, 1995.

    Article  CAS  PubMed  Google Scholar 

  23. Ferdjallah, M. and Barr, R. E.,Frequency-domain digital filtering techniques for the removal of powerline noise with application to the electrocardiogram, Comput and Biomed Res., 23: 479–489, 1990.

    Google Scholar 

  24. Huhta, J. C. and Webster, J. G.,60-Hz interference in electrocardiography, IEEE Trans Biomed Eng., 20: 91–101, 1973.

    Article  CAS  PubMed  Google Scholar 

  25. Jasper, H. H.,The ‘10–20’ system, Electroenceph Clin Neurophysiol., 10: 371–375, 1958.

    Google Scholar 

  26. Brown, B. H., Smallwood, R. H., Barber, D. C., Lawford, P. V. and Hose, D. R.,Medical physics and biomedical engineering, Institute of Physics Publishing, London, 1999.

    Book  Google Scholar 

  27. Dawson, G. D.,A summation technique for detecting small signals in a large irregular background, J Physiol., 115: 2P-3P, 1951.

    CAS  PubMed  Google Scholar 

  28. Misulis, K. E.,Essentials of clinical neurophysiology. Butterworth-Heinemann, MA, USA, 1997.

    Google Scholar 

  29. Regan, D.,Human brain electrophysiology: evoked potentials and evoked magnetic fields in science and medicine, Elsevier, New York, 1989.

    Google Scholar 

  30. Siberstein, R. B. and Cadusch, P. J.,Measurement processes and spatial principal component analysis, Brain Topogr., 4: 267–276, 1992.

    Article  Google Scholar 

  31. Nunez, P. L.,Neocortical dynamics and human EEG rythms. 1995.

  32. van der Tweel, L. H. and Verduyn, L. H. F. E.,Human visual responses to sinusoidally modulated light, Electroenceph Clin Neurophysiol., 18: 587–598, 1965.

    Article  Google Scholar 

  33. Geisler, C. D., Frishkopf, L. S. and Rosenblith, W. A.,Extracranial responses to acoustic clicks in man, Science, 128: 1210–1211, 1958.

    Article  CAS  PubMed  Google Scholar 

  34. Tompkins, W. J. and Webster, J. G.,Design of microprocessorbased medical instrumentation, Prentice-Hall Inc, Englewood Cliffs, New Jersey, 1981.

    Google Scholar 

  35. Barr, R. E. and Ferdjallah, M.,Frequency domain digital filtering techniques for selective noise elimination in biomedical signal processing, IEEE Comp in Cardiol., 12: 813–814, 1990.

    Google Scholar 

  36. Widrow, B., Glover, J. R., Jr., McCool, J. M., Kaunitz, J., Williams, C. S., Hearn, R. H., Zeidler, J. R., Dong, E., Jr. and Goodlin, R. C.,Adaptive noise-cancelling: Principles and applications, IEEE Proc., 63: 1692–1716, 1975.

    Article  Google Scholar 

  37. Ogatta, K.,Modern control engineering, 2 ed. Prentice-Hall Inc, Englewood Cliffs, New Jersey, 1990.

    Google Scholar 

  38. Bronzino, J. D.,The biomedical engineering handbook. CRC Press Inc., USA, 1995.

    Google Scholar 

  39. Ifeachor, E. C. and Jervis, B.W.,Digital signal processing: a practical approach, Addison-Wesley Publishers, USA, 1993.

    Google Scholar 

  40. Johnson, J. B.,Thermal agitation of electricity in conductors, Phys. Rev., 32: 97 1928.

    Article  CAS  Google Scholar 

  41. Nelson, W. R.,Interference handbook. Radio Publications Inc, Wilton, 1981.

    Google Scholar 

  42. Ott, H. W., Noise reduction techniques in electronic systems, John Wiley & Son, USA, 1988.

    Google Scholar 

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Authors and Affiliations

  1. The Walter and Eliza Hall Institute of Medical Research, Royal Melbourne Hospital, P. O. Box 2041, 3050, Parkville, Victoria, Australia

    H. A. Sadafi

  2. School of Biophysical Sciences & Electrical Engineering, Swinburne University of Technology, Hawthorn, Australia

    P. Cadusch & A. W. Wood

Authors
  1. H. A. Sadafi
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  2. P. Cadusch
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  3. A. W. Wood
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Correspondence to H. A. Sadafi.

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Sadafi, H.A., Cadusch, P. & Wood, A.W. Real-time recording of neuropsychophysiological parameters during 50 Hz magnetic field exposure. Australas. Phys. Eng. Sci. Med. 28, 43 (2005). https://doi.org/10.1007/BF03178863

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  • DOI: https://doi.org/10.1007/BF03178863

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