Dear Max,
I would give Ben's suggestion a try and just change:
matlabbatch{1}.spm.tools.fieldmap.presubphasemag.subj.defaults.defaultsval.blipdir = 1;
to
matlabbatch{1}.spm.tools.fieldmap.presubphasemag.subj.defaults.defaultsval.blipdir = -1;
and see what happens. Maybe that will solve your problem.
Siawoosh
-------- Original-Nachricht --------
> Datum: Wed, 28 Nov 2012 08:25:05 +0000
> Von: Maximilian Hilger <[log in to unmask]>
> An: "[log in to unmask]" <[log in to unmask]>
> Betreff: Re: [SPM] Inverted effect of phasemap
> Dear Ben,
>
> thanks for your suggestion!
>
> We did check the blip direction, it is set to +1 (or +ve, when using the
> fieldmap toolbox instead of the batch tool), as it is standard in our lab.
> This also resulted the phasemap meeting our expectations during visual
> examinations, having relatively high positive values in the frontal lobe. Still,
> these parts associated with positive phasemap-values seem to shrink
> instead of expanding upon unwarping.
>
> Best,
> Max
>
>
> 2012/11/28 Ben de Haas
> <[log in to unmask]<mailto:[log in to unmask]>>
> Dear Max,
>
> I'm far from being an expert, but did you double-check the blip direction?
>
> Best,
> Ben
>
--
Dr. Siawoosh Mohammadi
Post Doctoral Research Fellow
Wellcome Trust Center for Neuroimaging
Institute of Neurology
University College London
12 Queen Square
London WC1N 3BG
United Kingdom
Tel. +44-20-344-84368, (internal ext 84368)
Fax. +44-20-7813-1420
[log in to unmask]
--
Dr. Siawoosh Mohammadi
Post Doctoral Research Fellow
Wellcome Trust Center for Neuroimaging
Institute of Neurology
University College London
12 Queen Square
London WC1N 3BG
United Kingdom
Tel. +44-20-344-84368, (internal ext 84368)
Fax. +44-20-7813-1420
[log in to unmask]
