Dear all,
just to let you know that an implementation of multiband slice timing
correction will make its way shortly in SPM12b. It is a contribution
from Michael Woletz and colleagues from the Medical University of
Vienna, Austria. Their work will be described in a poster at HBM next
week (number 3484).
I haven't looked at your code Michael (thanks for sharing!) but I assume
it should be very similar - with perhaps a difference in how the extra
parameters are specified.
Best regards,
Guillaume.
On 02/06/14 18:02, Michael Erb wrote:
> Hi all,
>
> here my solution to the Multiband Slice timing. I have changed the code
> so that for multi band the slice order is an array where each row give
> the slices which are measured at the same timepoint
>
> % Multi-Band: array
> % [ [ 1 4] same timepoint 1
> % [ 3 6] same timepoint 2
> % [ 2 5] ] same timepoint 3
>
> Hope it works also for you.
>
> Regards,
>
> Michael
>
>
> Am 02.06.2014 15:57, schrieb Torben Lund:
>> That is right. Looking at the code it seems that nslices is rather
>> fundamental for the way the code works, and that extra matlab coding
>> will be needed. You could either rewrite the spm_slicetiming.m code or
>> alternatively split each of the current volumes into (in our example)
>> three volumes, and perform the correction on each of the segments
>> seperately, and then after the correction merge the volumes again. Much
>> better would of course be a slice specific designmatrix in which case
>> this would not be a problem.
>>
>> Best
>> Torben
>>
>>
>> Torben Ellegaard Lund
>> Associate Professor, PhD
>> Center of Functionally Integrative Neuroscience (CFIN)
>> Aarhus University
>> Aarhus University Hospital
>> Building 10G, 5th floor, room 31
>> Noerrebrogade 44
>> 8000 Aarhus C
>> Denmark
>> Phone: +45 7846 4380
>> Fax: +45 7846 4400
>> http://www.cfin.au.dk <http://www.cfin.au.dk/>
>> [log in to unmask] <mailto:[log in to unmask]>
>>
>>
>>
>>
>>
>> Den Uge:23 02/06/2014 kl. 13.37 skrev Rajat Thomas <[log in to unmask]
>> <mailto:[log in to unmask]>>:
>>
>>> Hi Torben,
>>>
>>> Thank you for your suggestion. I think it is a good compromise because
>>> in this case for example, 1 3 5 which should be offset by zero
>>> (because its acquired simultaneously) but will be offset by TR/15
>>> (using default SPM). Indeed for TRs < 1s, this would be negligible.
>>>
>>> Cheers,
>>>
>>> Rajat
>>>
>>>
>>>
>>> Rajat Mani Thomas
>>> Social Brain Lab
>>> Netherlands Institute for Neuroscience
>>> Amsterdam
>>> ------------------------------------------------------------------------
>>> *From:*Torben Lund <[log in to unmask] <mailto:[log in to unmask]>>
>>> *Sent:*02 June 2014 11:48
>>> *To:*Rajat Thomas
>>> *Cc:*spm Parametric Mapping)
>>> *Subject:*Re: [SPM] Multiband Slice timing
>>> Hi Rajat
>>>
>>> This is a wild guess which I have not testet, but have you tried
>>> a sliceorder vector which reflects the situation e.g. with 15 slices
>>> and multislice acceleration of 3 [1 3 5 2 4 1 3 5 2 4 1 3 5 2 4 ]
>>>
>>> Best
>>> Torben
>>>
>>>
>>> Torben Ellegaard Lund
>>> Associate Professor, PhD
>>> Center of Functionally Integrative Neuroscience (CFIN)
>>> Aarhus University
>>> Aarhus University Hospital
>>> Building 10G, 5th floor, room 31
>>> Noerrebrogade 44
>>> 8000 Aarhus C
>>> Denmark
>>> Phone: +45 7846 4380
>>> Fax: +45 7846 4400
>>> http://www.cfin.au.dk <http://www.cfin.au.dk/>
>>> [log in to unmask] <mailto:[log in to unmask]>
>>>
>>>
>>>
>>>
>>>
>>> Den Uge:23 02/06/2014 kl. 11.08 skrev Rajat Thomas
>>> <[log in to unmask] <mailto:[log in to unmask]>>:
>>>
>>>> ​Dear SPMers,
>>>>
>>>> Any suggestion on how to perform multiband slice timing in SPM?
>>>>
>>>> Thanks.
>>>>
>>>> Rajat
>>>>
>>>>
>>>>
>>>> Rajat Mani Thomas
>>>> Social Brain Lab
>>>> Netherlands Institute for Neuroscience
>>>> Amsterdam
>>
>
--
Guillaume Flandin, PhD
Wellcome Trust Centre for Neuroimaging
University College London
12 Queen Square
London WC1N 3BG
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