Hi,
On 30 Apr 2007, at 08:54, Xuelin Cui wrote:
> hi folks:
>
> I ran MELODIC for fMRI data, and thus have a bunch of independent
> components which are displayed by a html file. In the html file,
> there is a spatial map, a time course, as well as a Fourier
> spectrum of the time course.
>
> I have some questions on those in the html file:
>
> 1. Are all the spatial maps in single html file snapped at
> different time point? IF so what time are they?
>
No
> 2. What is the relation between the time course and the spatial map
> in the same html file?
>
They express the spatial and temporal characteristics of a component
- in a similar way that EVs (regressors in the GLM) and the
associated maps of parameter estimates express BOLD modulation. That
is, the spatial maps corresponds to a map of parameter estimates and
the time course describes how that spatial map is modulated in
strength at different time points.
> 3. Are the 125 points time course variance corresponds to a certain
> voxel in the brain? If so, which voxel is it? If not, what is it
> related to? Some certain region?
>
Likewise, the time course is related to the entire IC map - not to a
single voxel.
cheers
christian
> Thanks a lot
>
> Xuelin
>
> ****************************************
> Xuelin Cui
> Department of Electrical Engineering
> University of Hawaii-Manoa
> Honolulu HI 96822
>
> Tel: 1-808-349-0983
> Email: [log in to unmask]
> ****************************************
____
Christian F. Beckmann
University Research Lecturer
Oxford University Centre for Functional MRI of the Brain (FMRIB)
John Radcliffe Hospital, Headington, Oxford OX3 9DU, UK.
[log in to unmask] http://www.fmrib.ox.ac.uk/~beckmann
tel: +44 1865 222551 fax: +44 1865 222717
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