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Dear Will, list,
I really appreciate the HBM2 PDFs on the the link you mentioned. It is a great overview of the algorithms underlying SPM2.
My question: can I use this material for courses here in our institute? I am expected to give trainings to researchers in fMRI analysis, and this material would come in handy as handouts. But I assume it underlies some form of copyright, although the site only says it cannot be reposted (online?) without permission. Would it be OK to provide copies of some chapters during our in house trainings?
Cheers,
Bas
-----Original Message-----
From: SPM (Statistical Parametric Mapping) on behalf of Will Penny
Sent: Fri 1/14/2005 19:25
To: [log in to unmask]
Cc:
Subject: Re: [SPM] How to use contrast?
Dear Kohkichi Hosada,
If you get the same results using either method
then I would see that as good news. Your effects
are so robust that even SPM can't mess them up.
More seriously, many of these options are described in
a book chapter available from our website:
http://www.fil.ion.ucl.ac.uk/spm/doc/books/hbf2/pdfs/Ch7.pdf
Best wishes,
Will.
Kohkichi Hosoda wrote:
> Dear Will and Zoltan,
>
> Thank you guys for providing excellent explanations. I appreciate it
> veru much. Could I ask you a second question? ;-)
>
> As you can see, I am carrying out a clinical examination, in which I
> compare each patient value with normal values derived from 27 controls
> on MRI after normalization of all patients and control images. In the
> previous mail, I wrote that I did not use "grand mean scaling",
> "Threshold masking", "threshold", "Implicit mask", "explicitly mask",
> "Global calculation", and "non-sphericity correction." However, I
> realized that this was a first-level analysis. Therefore, I thought I
> should have used some of them, and I tried to use them in GUI of SPM2
> as followings;
>
> 1. grand mean scaling ---> scaling of overall grand mean
> 2. scale overall grand mean to ---> 50
> 3. Threshold masking ---> relative
> 4. threshold (relative to global) ---> 0.8
> 5. Implicit mask (ignore zero's)? ---> no
> 6. explicitly mask images? ---> no
> 7. Global calculation ---> mean voxel value (within per image
> fullmean/8 mask)
> 8. non-sphericity correction? ---> no
>
> Then, I obtained very similar results to those when I said no to all
> options described above. I am wondering which is the correct way and
> which values are correct if I should use grand mean scaling and
> masking etc. I would appreciate any help very much in advance.
>
> --
> Kohkichi Hosoda M.D.
>
> Department of Neurosurgery,
> Hyogo Emergency Medical Center/Kobe Red Cross Hospital,
> 1-3-1 Wakinohama-Kaigan-Dori, Chuo-ku, Kobe, 651-0073, JAPAN
> Telephone 078-241-3131
> Fax 078-241-2772
> e-mail address : [log in to unmask]
>
>
>
--
William D. Penny
Wellcome Department of Imaging Neuroscience
University College London
12 Queen Square
London WC1N 3BG
Tel: 020 7833 7475
FAX: 020 7813 1420
Email: [log in to unmask]
URL: http://www.fil.ion.ucl.ac.uk/~wpenny/