Paper Info
Title
The global signal in fMRI: Nuisance or Information?
Abstract
The global signal is widely used as a regressor or normalization factor for removing the effects of global variations in the analysis of functional magnetic resonance imaging (fMRI) studies. However, there is considerable controversy over its use because of the potential bias that can be introduced when it is applied to the analysis of both task-related and resting-state fMRI studies. In this paper we take a closer look at the global signal, examining in detail the various sources that can contribute to the signal. For the most part, the global signal has been treated as a nuisance term, but there is growing evidence that it may also contain valuable information. We also examine the various ways that the global signal has been used in the analysis of fMRI data, including global signal regression, global signal subtraction, and global signal normalization. Furthermore, we describe new ways for understanding the effects of global signal regression and its relation to the other approaches.
Year
DOI
Venue
2017
10.1016/j.neuroimage.2017.02.036
NeuroImage
Keywords
Field
DocType
fMRI,Global signal,Physiological noise,Vigilance,Motion,General linear model
Econometrics,Normalization (statistics),Functional magnetic resonance imaging,Regression,Pattern recognition,General linear model,Psychology,Cognitive psychology,Vigilance (psychology),Artificial intelligence,Communication noise,Subtraction
Journal
Volume
ISSN
Citations 
150
1053-8119
36
PageRank 
References 
Authors
1.05
46
3
Name
Order
Citations
PageRank
Thomas T Liu1102276.03
Alican Nalci2483.23
maryam falahpour3442.22