Roberto,
> > Our initial thought was to use spm_est_smoothness.m & spm_resels.m
> > Using a temporal lobe mask, we should be able to obtain a FWHM
> > estimate for the temporal lobe area of each ADC-map, and after that a
> > resel count for the temporal lobe. Then, we would apply a Bonferroni
> > correction with the number of resels in stead of the number of voxels.
>
> I am not sure I remember well, but I think there is actually a warning
> somewhere that doing a Bonferroni correction with the resels count does
> not give the same result as the random field theory test. It would be
> interesting to have some simulations clarifying what happens when you
> do this.
Keith Worsley has mentioned the problems of using a 'RESEL Bonferroni'
correction, but I'm not sure if he has ever written anything about it.
In [1] we reported the problem in math mode in section 3.2.3, and with
simulations showed how it was very anticonservative (rejected too
often) for all smoothness and df considered (see Fig 6).
-Tom
[1] Nichols & Hayasaka
Controlling the familywise error rate in functional neuroimaging:
a comparative review
Statistical Methods in Medical Research, 2003; 12: 419-446
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