Enhancing Functional Neuroimages: Wavelet Denoising as an Alternative to Gaussian Smoothing

نویسندگان

  • Alle Meije Wink
  • Jos B.T.M. Roerdink
چکیده

We present a general wavelet-based denoising scheme for functional neuroimages and compare it to Gaussian smoothing, the standard method in functional neuroimaging. We adapted WaveLab thresholding routines to 2D data, and tested their effect on the signal-to-noise ratio of noisy images. In a simulated time series test, we also investigated the shapes of detected activations after denoising. keywords: Wavelets, functional neuroimaging, denoising, signal-to-noise ratio

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تاریخ انتشار 2002