Basic Aspects of Magnetic Resonance Functional Neuroimaging: Physiology, Signals and Maps
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 . 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.
KeywordsFunctional Magnetie Resonance Imaging Magnetie Resonance Imaging Signal Human Motor Cortex Magnetie Resonance Imaging Signal Intensity Luminance Modulation
Unable to display preview. Download preview PDF.
- 1.Raichle ME (1987) The Nervous system. In: Mountcastle VB (ed.) Handbook of physiology, Sect. 1, Vol: 5. AmericanGoogle Scholar
- Physiological Society, pp. 643–674Google Scholar
- 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
- 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
- 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
- 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
- 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
- 14.Kleinschmidt A, Nitschke M, Frahm (1996) Somatotopy in the human motor cortex and area (submitted)Google Scholar