The ins and outs of fMRI signals

@article{Logothetis2007TheIA,
  title={The ins and outs of fMRI signals},
  author={Nikos K. Logothetis},
  journal={Nature Neuroscience},
  year={2007},
  volume={10},
  pages={1230-1232}
}
Despite the widespread use of functional magnetic resonance imaging, we still do not fully understand what it measures. A new study reports that oxygen-concentration changes and local field potentials are concurrent in time and space. 
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In the version of this article initially published online, the labeling on Figure 1c was incorrect and the error has been corrected in the HTML and PDF versions of the article.
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