Vector-based spatial-temporal minimum L1-norm solution for MEG

Ming Xiong Huang, Anders M. Dale, Tao Song, Eric Halgren, Deborah L. Harrington, Igor Podgorny, Jose M. Canive, Stephen Lewis, Roland R. Lee

Research output: Contribution to journalArticle

74 Citations (Scopus)

Abstract

Minimum L1-norm solutions have been used by many investigators to analyze MEG responses because they provide high spatial resolution images. However, conventional minimum L1-norm approaches suffer from instability in spatial construction, and poor smoothness of the reconstructed source time-courses. Activity commonly "jumps" from one grid point to (usually) the neighboring grid points. Equivalently, the time-course of one specific grid point can show substantial "spiky-looking" discontinuity. In the present study, we present a new vector-based spatial-temporal analysis using a L1-minimum-norm (VESTAL). This approach is based on a principle of MEG physics: the magnetic waveforms in sensor-space are linear functions of the source time-courses in the imaging-space. Our computer simulations showed that VESTAL provides good reconstruction of the source amplitude and orientation, with high stability and resolution in both the spatial and temporal domains. "Spiky-looking" discontinuity was not observed in the source time-courses. Importantly, the simulations also showed that VESTAL can resolve sources that are 100% correlated. We then examined the performance of VESTAL in the analysis of human median-nerve MEG responses. The results demonstrated that this method easily distinguishes sources very spatially close to each other, including individual primary somatosensory areas (BA 1, 2, 3b), primary motor area (BA 4), and other regions in the somatosensory system (e.g., BA 5, 7, SII, SMA, and temporal-parietal junction) with high temporal stability and resolution. VESTAL's potential for obtaining information on source extent was also examined.

Original languageEnglish (US)
Pages (from-to)1025-1037
Number of pages13
JournalNeuroImage
Volume31
Issue number3
DOIs
StatePublished - Jul 1 2006
Externally publishedYes

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Spatio-Temporal Analysis
Somatosensory Cortex
Median Nerve
Physics
Motor Cortex
Computer Simulation
Research Personnel
N-methyl-valyl-amiclenomycin
N-(2-cyanoethylene)urea

Keywords

  • Dipole
  • L1-norm
  • Lead field
  • Median-nerve
  • MEG
  • Minimum norm
  • Spatial-temporal

ASJC Scopus subject areas

  • Neurology
  • Cognitive Neuroscience

Cite this

Huang, M. X., Dale, A. M., Song, T., Halgren, E., Harrington, D. L., Podgorny, I., ... Lee, R. R. (2006). Vector-based spatial-temporal minimum L1-norm solution for MEG. NeuroImage, 31(3), 1025-1037. https://doi.org/10.1016/j.neuroimage.2006.01.029

Vector-based spatial-temporal minimum L1-norm solution for MEG. / Huang, Ming Xiong; Dale, Anders M.; Song, Tao; Halgren, Eric; Harrington, Deborah L.; Podgorny, Igor; Canive, Jose M.; Lewis, Stephen; Lee, Roland R.

In: NeuroImage, Vol. 31, No. 3, 01.07.2006, p. 1025-1037.

Research output: Contribution to journalArticle

Huang, MX, Dale, AM, Song, T, Halgren, E, Harrington, DL, Podgorny, I, Canive, JM, Lewis, S & Lee, RR 2006, 'Vector-based spatial-temporal minimum L1-norm solution for MEG', NeuroImage, vol. 31, no. 3, pp. 1025-1037. https://doi.org/10.1016/j.neuroimage.2006.01.029
Huang MX, Dale AM, Song T, Halgren E, Harrington DL, Podgorny I et al. Vector-based spatial-temporal minimum L1-norm solution for MEG. NeuroImage. 2006 Jul 1;31(3):1025-1037. https://doi.org/10.1016/j.neuroimage.2006.01.029
Huang, Ming Xiong ; Dale, Anders M. ; Song, Tao ; Halgren, Eric ; Harrington, Deborah L. ; Podgorny, Igor ; Canive, Jose M. ; Lewis, Stephen ; Lee, Roland R. / Vector-based spatial-temporal minimum L1-norm solution for MEG. In: NeuroImage. 2006 ; Vol. 31, No. 3. pp. 1025-1037.
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