Skip to main content
SpringerLink
Log in

Thickness and resistivity variations over the upper surface of the human skull

  • Published:
Brain Topography Aims and scope Submit manuscript

Summary

A study of skull thickness and resistivity variations over the upper surface was made for an adult human skull. Physical measurements of thickness and qualitative analysis of photographs and CT scans of the skull were performed to determine internal and external features of the skull. Resistivity measurements were made using the four-electrode method and ranged from 1360 to 21400 Ohm-cm with an overall mean of 7560±4130 Ohm-cm. The presence of sutures was found to decrease resistivity substantially. The absence of cancellous bone was found to increase resistivity, particularly for samples from the temporal bone. An inverse relationship between skull thickness and resistivity was determined for trilayer bone (n=12, p<0.001). The results suggest that the skull cannot be considered a uniform layer and that local resistivity variations should be incorporated into realistic geometric and resistive head models to improve resolution in EEC Influences of these variations on head models, methods for determining these variations, and incorporation into realistic head models, are discussed.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Log in via an institution

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Institutional subscriptions

Similar content being viewed by others

References

  • Bass, W.M. Human Osteology, 2nd ed. Columbia: Missouri Archaeology Society, 1981.

    Google Scholar 

  • Black, J. and Mattson, R.U. Relationship between porosity and mineralization in the Haversian osteon. Calcif. Tissue Int., 1982, 34: 332–336.

    Google Scholar 

  • Butler, S.R., Fisher, S. and Glass, A. EEG asymmetry and skull thickness. Electroenceph. clin. Neurophy., 1986, 63: 79-P.

    Google Scholar 

  • Chakkalakal, D.A. and Johnson, M.W. Electrical properties of compact bone. Clin. Ortho. Rel. Res., 1981, 161: 133–145.

    Google Scholar 

  • Chakkalakal, D.A., Johnson, M.W., Harper, R.A. and Katz, J.L. Dielectric properties of fluid-saturated bone. IEEE Trans. Biomed. Engr., 1980, 27(2): 95–100.

    Google Scholar 

  • Cuffin, B.N. Effects of local variations in skull and scalp thickness on EEG's and MEG's, IEEE Trans. Biomed. Engr., 1993, 40: 42–48.

    Google Scholar 

  • Cuffin, B.N. Effects of head shape on EEGs and MEGs. IEEE Trans. Biomed. Engr., 1990, 37: 44–52.

    Google Scholar 

  • Cuffin, B.N., Cohen, D., Yunokuchi, K., Maniewski, R., Purcell, C., Cosgrove, M., Ives, J., Kennedy, J. sand, Schomer, D. Tests of EEG localization accuracy using implanted sources in the human brain. Ann. Neurol., 1991, 29: 132–138.

    Google Scholar 

  • Fabiani, M., Gratton, G., Karis, D. and Donchin, E. Definition, identification, and reliability of measurment of the P300 component of the event-related brain potential. Adv. Pschophys., 1987, 2: 1–78.

    Google Scholar 

  • Farkas, L.G. Anthropometry of the head and face in medicine. New York: Elsevier, 1981.

    Google Scholar 

  • Fender, D.H. Models of the human brain and the surrounding media: Their influence on the reliability of source localization. J. Clin. Neurophys., 1991, 8: 381–390.

    Google Scholar 

  • Garfin, S.R., Botte, M.J., Centeno, R.S. and Nickel, V.L. Osetology of the skull as it affects halo pin placement. Spine, 1985, 10: 696–698.

    Google Scholar 

  • Geddes, L.A. and Baker, L.E. The specific resistance of biological material-a compendium of data for the biomedical engineer and physiologist. Med. biol. Engr., 1967, 5: 271–293.

    Google Scholar 

  • Gevins, A., Le, J., Brickett, P., Reutter, B. and Desmond, J. Seeing through the skull: Advanced EEGs use MRIs to accurately measure cortical activity from the scalp. Brain Topogr., 1991, 4: 125–131.

    Google Scholar 

  • Goodin, D.S., Squires, K.C., Henderson, B.H. and Starr, A. Age-related variations in evoked potentials to auditory stimuli in normal human subjects. Electroenceph. clin. Neurophys., 1978, 44: 447–458.

    Google Scholar 

  • He, B., Musha, T., Okamoto, Y., Homma, S., Nakajima, Y. and Sato, T. Electric dipole tracing in the brain by means of the boundary element method and its accuracy. IEEE Trans. Biomed. Engr., 1987, 34: 406–414.

    Google Scholar 

  • Hildebolt, C.F., Vannier, M.W. and Knapp, R.H. Validation study of skull three-dimensional computerized tomography measurements. Am. J. Phys. Anthr., 1990, 82: 283–294.

    Google Scholar 

  • Hildebolt, C.F. and Vannier, M.W. Three-dimensional measurement accuracy of skull surface landmarks. Am. J. Phys. Anthr., 1988, 76: 497–503.

    Google Scholar 

  • Howells, W. Cranial variation in man. Papers of the Peabody Museum No. 67, Harvard University, 1973.

  • Johnson, R.W. Developmental evidence for modality-dependent P300 generators: A normative study. Psychophys., 1989, 26: 651–667.

    Google Scholar 

  • Katznelson, R.D. Normal modes of the brain: neuroanatomical basis and a physiological theoretical model. In: P.L. Nunez (Ed.), Electric Fields of the Brain: The Neurophysics of EEC. New York: Oxford University Press, 1981: 401–442.

    Google Scholar 

  • Kearfott, R.B., Sidmann, R.D., Major, D.J. and Hill, C.D. Numberical tests of a method for simulating electrical potentials on the cortical surface. IEEE Trans. Biomed. Engr., 1991, 38: 294–299.

    Google Scholar 

  • Kosterich, J.D., Foster, K.R. and Pollack, S.R. Dielectric properties of fluid-saturated bone-the effect of variation in conductivity of immersion fluid. IEEE Trans. Biomed. Engr., 1984, 31: 369–373.

    Google Scholar 

  • Law, S.K., Nunez, P.L. and Wijesinghe, R.S. High resolution EEG using spline generated surface Laplacians on spherical and ellipsoidal surfaces. IEEE Trans. Biomed. Engr., 1993, 40: 145–153.

    Google Scholar 

  • Leissner, P., Lindhom, L.E. and Peterson, I. Alpha amplitude dependence on skull thickness as measured by utrasound technique. Electroenceph. clin. Neurophys., 1970, 29: 392–399.

    Google Scholar 

  • Manzanares, M.C., Goret-Nicaise, M. and Dhem, A. Metopic sutural closure in the human skull. J. Anat., 1988, 161: 203–215.

    Google Scholar 

  • Marino, F.E. The passive propagation of electric fields inside the head modeled by the finite difference method. Master's thesis, Department of Computer Science, University of California at Los Angeles, Los Angeles, 1991.

    Google Scholar 

  • Mullis, R.J., Holcomb, P.J., Diner, B.C. and Dykman, R.A. The effects of aging on the P3 components of the visual event-related potential. Electroenceph. clin. Neurophys., 1985, 62: 141–149.

    Google Scholar 

  • Nawrocki, S.P. Cranial thickness and skull biomechanics in Archaic Homo. Am. J. Phys. Anthro., 1992, Supplement 14: 127.

    Google Scholar 

  • Nawrocki, S.P. A biomechanical model of cranial vault thickness in archaic homo. Doctoral Dissertation, University of New York at Binghamton, 1991.

    Google Scholar 

  • Nunez, P.L and Pilgreen, K.L. The spline-Laplacian in clinical neurophysiology: a method to improve EEG spatial resolution. J. Clin. Neurophys., 1991, 8(4): 397–413.

    Google Scholar 

  • Nunez, P.L., Pilgreen, K.L., Westdorp, A.F., Law, S.K. and Nelson, A.V. A visual study of surface potentials and Laplacians due to distributed neocortical sources: Computer simulations and evoked potentials. Brain Topogr., 1991, 4:(2): 151–167.

    Google Scholar 

  • Pfefferbaum, A. Model estimates of CSF and skull influences on scalp-recorded ERPs. Alcohol, 1990, 7: 479–482.

    Google Scholar 

  • Pfefferbaum, A. and Rosenbloom, M.A. Skull thickness influences P3 amplitude. Psych. Pharm. Bul., 1987, 23: 493–496.

    Google Scholar 

  • Pfefferbaum, D., Ford, J.M., Wenegrat, B.G., Roth, W.T. and Kopell, B.S. Clinical application of the P3 component of event-related potentials. Normal aging. Electroenceph. clin. Neurophys., 1984, 59: 85–103.

    Google Scholar 

  • Poulnot, M., Lesser, G., Law, S.K., Westdorp, A.F. and Nunez, P.L. Determination of the electrical impedance of the bones of the skull. Report to the Brain Physics Group, Department of Biomedical Engineering, Tulane University, New Orleans, 1989.

    Google Scholar 

  • Rush, S. and Driscoll, D.A. EEG electrode sensitivity-an application of reciprocity. IEEE Trans. Biomed. Engr., 1969, 16: 15–22.

    Google Scholar 

  • Scherg, M. Fundamentals of dipole source potential analysis. In: M. Hoke, F. Grandori and G.L. Romani (Eds), Auditory Evoked Magnetic Fields and Potentials: Advances in Neurology, vol. 6. Basel: Karger, 1989.

    Google Scholar 

  • Schwan, H.P. Electrode polarization impedance and measurements in biological materials. Ann. N.Y. Acad. Sci., 1968, 148: 191–209.

    Google Scholar 

  • Shipman, P., Walker, A. and Bichell, D. The human skeleton. Cambridge, MA: Harvard University Press, 1985.

    Google Scholar 

  • Todd, T.W. Thickness of the male white cranium. Anat. Rec., 1924, 27: 245–255.

    Google Scholar 

  • Woolley, S.C., Borthwich, J.W., Gentle, M.J. Tissure resistivities and current pathways and their importance in pre-slaughter stunning of chickens. Br. Poul. Sci., 1986, 27: 301–306.

    Google Scholar 

  • Yan, Y., Nunez, P.L. and Hart, R.T. A finite element model of the human head. Med. Biol. Eng. Comput., 1991, 29: 475–481.

    Google Scholar 

Download references

Author information

Authors and Affiliations

  1. Section of Brain Electrophysiology and Imaging, Laboratory of Clinical Studies, National Institute on Alcohol Abuse and Alcoholism, Bethesda, Maryland

    Samuel K. Law

Authors
  1. Samuel K. Law
    View author publications

    You can also search for this author in PubMed Google Scholar

Additional information

The author would like to acknowledge James V. Sullivan and Paul Fitze of the Precision Instrument Unit of the Biomedical Engineering and Instrumentation Program, National Institutes of Health for their expert drilling of the skull, preparation of the samples, and fabrication of the four-electrode test assembly. The author would like to thank Drs. Michael J. Eckardt and Dan Hommer of the Lab. of Clinical Studies, NIAAA, for their review and comments of the manuscript, and Dr. Stephen Nawrocki, Deptartment of Biology, University of Indianapolis, for sharing his expertise in the study of the human cranium. Preliminary experiments were performed under Dr. Paul Nunez, Department of Biomedical Engineering, Tulane University, New Orleans, LA, supported by NIH grant R01-NS243314.

Rights and permissions

Reprints and permissions

About this article

Cite this article

Law, S.K. Thickness and resistivity variations over the upper surface of the human skull. Brain Topogr 6, 99–109 (1993). https://doi.org/10.1007/BF01191074

Download citation

  • Accepted:

  • Issue Date:

  • DOI: https://doi.org/10.1007/BF01191074

Key words

Search

Navigation