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Title: Discussion on “distributional independent component analysis for diverse neuroimaging modalities” by Ben Wu, Subhadip Pal, Jian Kang, and Ying Guo
Abstract

I applaud the authors on their innovative generalized independent component analysis (ICA) framework for neuroimaging data. Although ICA has enjoyed great popularity for the analysis of functional magnetic resonance imaging (fMRI) data, its applicability to other modalities has been limited because standard ICA algorithms may not be directly applicable to a diversity of data representations. This is particularly true for single‐subject structural neuroimaging, where only a single measurement is collected at each location in the brain. The ingenious idea of Wuet al.(2021) is to transform the data to a vector of probabilities via a mixture distribution withKcomponents, which (following a simple transformation to ) can be directly analyzed with standard ICA algorithms, such as infomax (Bell and Sejnowski, 1995) or fastICA (Hyvarinen, 1999). The underlying distribution forming the basis of the mixture is customized to the particular modality being analyzed. This framework, termeddistributional ICA(DICA), is applicable in theory to nearly any neuroimaging modality. This has substantial implications for ICA as a general tool for neuroimaging analysis, with particular promise for structural modalities and multimodal studies. This invited commentary focuses on the applicability and potential of DICA for different neuroimaging modalities, questions around details of implementation and performance, and limitations of the validation study presented in the paper.

 
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NSF-PAR ID:
10397028
Author(s) / Creator(s):
 
Publisher / Repository:
Oxford University Press
Date Published:
Journal Name:
Biometrics
Volume:
78
Issue:
3
ISSN:
0006-341X
Format(s):
Medium: X Size: p. 1109-1112
Size(s):
p. 1109-1112
Sponsoring Org:
National Science Foundation
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