A unified statistical approach for determining significant signals in images of cerebral activation

@article{Worsley1996AUS,
  title={A unified statistical approach for determining significant signals in images of cerebral activation},
  author={Keith J. Worsley and Sean Marrett and Peter Neelin and Alain C. Vandal and Karl J. Friston and Alan C. Evans},
  journal={Human Brain Mapping},
  year={1996},
  volume={4}
}
We present a unified statistical theory for assessing the significance of apparent signal observed in noisy difference images. The results are usable in a wide range of applications, including fMRI, but are discussed with particular reference to PET images which represent changes in cerebral blood flow elicited by a specific cognitive or sensorimotor task. Our main result is an estimate of the P‐value for local maxima of Gaussian, t, χ2 and F fields over search regions of any shape or size in… 
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  • Biology
    Proceedings of the National Academy of Sciences of the United States of America
  • 1992
We report that visual stimulation produces an easily detectable (5-20%) transient increase in the intensity of water proton magnetic resonance signals in human primary visual cortex in gradient echo
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