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Linear transform model (MRI)

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The linear transform model refers to a fundamental assumption guiding the analysis of functional Magnetic Resonance Imaging (fMRI) studies. Specifically, the model holds that the fMRI signal is approximately proportional to a measure of local neural activity, averaged over a spatial extent of several millimeters and over a time period of several seconds.

Debate

The linear transform model is a common and widespread assumption used in the interpretation of fMRI studies. However, some scientists suggest reasons exist to remain sceptical. Heeger and Ress, in a review of fMRI and its relation to neuronal activity, argue that it is a reasonable and useful approximation for local neural activity "for some recording sites, in some brain areas, using certain experimental protocols", but it is not under other circumstances.[1]

See also

References

  1. ^ Heeger, D.J. & Ress, D. (February 2002). What does fMRI tell us about Neuronal Activity?, Nature Reviews, Volume 3, 142-151.