Advertisement

Basic Aspects of Magnetic Resonance Functional Neuroimaging: Physiology, Signals and Maps

  • J. Frahm
  • A. Kleinschmidt
  • G. Krüger
  • M. Requardt
  • K. D. Merboldt
  • W. Hänicke
Conference paper
Part of the Syllabus book series (SYLLABUS)

Abstract

The noninvasive window on human brain “function” offered by magnetic resonance imaging (MRI) is based on the fact that functional challenge causes regional changes in perfusion and metabolism affecting blood flow, volume, and oxygenation [1]. This contribution deals with the detectability of pertinent phenomena by MRI and their use for high-resolution functional neuroimaging. In particular, it covers physiologic and physical aspects of image acquisition as well as strategies for data evaluation and paradigm design. Although a variety of techniques have been proposed to monitor changes in perfusion and metabolism, we will focus on gradient echo MRI sequences that are sensitized to changes in cerebral blood oxygenation (CBO) and thus allow mapping of neuronal activation.

Keywords

Functional Magnetie Resonance Imaging Magnetie Resonance Imaging Signal Human Motor Cortex Magnetie Resonance Imaging Signal Intensity Luminance Modulation 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. 1.
    Raichle ME (1987) The Nervous system. In: Mountcastle VB (ed.) Handbook of physiology, Sect. 1, Vol: 5. AmericanGoogle Scholar
  2. Physiological Society, pp. 643–674Google Scholar
  3. 2.
    Frahm J, Krüger G, Merboldt KD, Kleinschmidt A (1996) Dynamic uncoupling and recoupling of perfusion and oxidative metabolism during focal brain activation in man. Magn Reson Med 35: 143–148PubMedCrossRefGoogle Scholar
  4. 3.
    Fox PT, Raichle ME (1986) Focal physiological uncoupling of cerebral blood flow and oxidative metabolism during somatosensory stimulation in human subjects. Proc Natl Acad Sci USA 83: 1140–1144PubMedCrossRefGoogle Scholar
  5. 4.
    Fox PT, Raichle ME, Mintun MA, Dence C (1988) Nonoxidative glucose consumption during focal physiologic neural activity. Science 241: 462–464PubMedCrossRefGoogle Scholar
  6. 5.
    Clarke DD, Sokoloff L (1994) Circulation and energy metbolism of the brain. In: Siegle GJ, Agranoff GW, Albers RW, Molinoff PB (eds) Basic neurochemistry, Raven, New York, pp. 645–680Google Scholar
  7. 6.
    Frahm J, Merboldt KD, Hänicke W (1993) Functional MRI of human brain activation at high spatial resolution. Magn Reson Med 29: 139–144PubMedCrossRefGoogle Scholar
  8. 7.
    Frahm J, Merboldt KD, Hänicke W, Kleinschmidt A, Boecker H (1994) Brain or vein — oxygenation or flow? On signal physiology in functional MRI of human brain activation. NMR Biomed 7: 45–53PubMedCrossRefGoogle Scholar
  9. 8.
    Krüger G, Kleinschmidt A, Frahm J (1996) Dynamic MRI of cerebral blood oxygenation and flow during sustained activation of human visual cortex. Magn Reson Med (in press)Google Scholar
  10. 9.
    Frahm J, Merboldt KD, Hänicke W (1995) The effects of intravoxel dephasing and incomplete slice refocusing on susceptibility contrast in gradient-echo MRI. J Magn Reson B 109: 234–237CrossRefGoogle Scholar
  11. 10.
    Bandettini PA, Jesmaniwicz A, Wong EC, Hyde JS (1993) Processing strategies for time-course data sets in functional MRI of the human brain. Magn Reson Med 30: 161–173PubMedCrossRefGoogle Scholar
  12. 11.
    Kleinschmidt A, Requardt M, Merboldt KD, Frahm J (1995) On the use of temporal correlation coefficients for magnetic resonance mapping of functional brain activation. Individualized thresholds and spatial response delineation. Intern J Imag Sys Technol 6: 238–244Google Scholar
  13. 12.
    Kleinschmidt A, Lee BB, Requardt M, Frahm J (1995) Functional mapping of color processing by magnetic resonance imaging of responses to selective P- and M-pathway stimulation. Exp Brain Res (in press)Google Scholar
  14. 13.
    Sanes JN, Donoghue JP, Thangaraj V, Edelman RR, Warach S (1995) Shared neural substrates controlling hand movements in human motor cortex. Science 268: 1775-1777Google Scholar
  15. 14.
    Kleinschmidt A, Nitschke M, Frahm (1996) Somatotopy in the human motor cortex and area (submitted)Google Scholar

Copyright information

© Springer-Verlag Italia, Milano 1996

Authors and Affiliations

  • J. Frahm
    • 1
  • A. Kleinschmidt
    • 1
  • G. Krüger
    • 1
  • M. Requardt
    • 1
  • K. D. Merboldt
    • 1
  • W. Hänicke
    • 1
  1. 1.Biomedizinische NMR Forschungs GmbH am Max-Planck-Institut für biophysikalische ChemieGöttingenGermany

Personalised recommendations