DocumentCode :
1170031
Title :
Standardized shrinking LORETA-FOCUSS (SSLOFO): a new algorithm for spatio-temporal EEG source reconstruction
Author :
Liu, Hesheng ; Schimpf, Paul H. ; Dong, Guoya ; Gao, Xiaorong ; Yang, Fusheng ; Gao, Shangkai
Author_Institution :
Sch. of Electr. Eng. & Comput. Sci., Washington State Univ., Spokane, WA, USA
Volume :
52
Issue :
10
fYear :
2005
Firstpage :
1681
Lastpage :
1691
Abstract :
This paper presents a new algorithm called Standardized Shrinking LORETA-FOCUSS (SSLOFO) for solving the electroencephalogram (EEG) inverse problem. Multiple techniques are combined in a single procedure to robustly reconstruct the underlying source distribution with high spatial resolution. This algorithm uses a recursive process which takes the smooth estimate of sLORETA as initialization and then employs the re-weighted minimum norm introduced by FOCUSS. An important technique called standardization is involved in the recursive process to enhance the localization ability. The algorithm is further improved by automatically adjusting the source space according to the estimate of the previous step, and by the inclusion of temporal information. Simulation studies are carried out on both spherical and realistic head models. The algorithm achieves very good localization ability on noise-free data. It is capable of recovering complex source configurations with arbitrary shapes and can produce high quality images of extended source distributions. We also characterized the performance with noisy data in a realistic head model. An important feature of this algorithm is that the temporal waveforms are clearly reconstructed, even for closely spaced sources. This provides a convenient way to estimate neural dynamics directly from the cortical sources.
Keywords :
brain models; electroencephalography; inverse problems; medical signal processing; neurophysiology; recursive estimation; signal reconstruction; signal resolution; spatiotemporal phenomena; cortical sources; electroencephalogram; head models; high spatial resolution; inverse problem; neural dynamics; spatio-temporal EEG source reconstruction; standardized shrinking LORETA-FOCUSS; temporal waveforms; Electroencephalography; Focusing; Head; Image reconstruction; Inverse problems; Noise shaping; Recursive estimation; Robustness; Spatial resolution; Standardization; EEG; inverse problem; spatio-temporal analysis; Action Potentials; Algorithms; Brain; Brain Mapping; Computer Simulation; Diagnosis, Computer-Assisted; Electroencephalography; Humans; Models, Neurological; Nerve Net; Reproducibility of Results; Sensitivity and Specificity;
fLanguage :
English
Journal_Title :
Biomedical Engineering, IEEE Transactions on
Publisher :
ieee
ISSN :
0018-9294
Type :
jour
DOI :
10.1109/TBME.2005.855720
Filename :
1510852
Link To Document :
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