Betheny,
Sorry for the bug in the ArtRepair toolbox. I use an older Matlab version and was not aware of this problem. You may safely just delete the aREADMEArtRepair_v5b.m file, or move it outside of the toolbox. Then the toolbox should work correctly.
A few very large spikes, 10-15 mm, is not necessarily a problem. ArtRepair will detect them, and interpolate through them using the temporal interpolation from the nearest good scans before and after. Thus, the large motions don't matter if they are detected as artifacts. The interpolation introduces a small error into the estimates of beta coefficients that are used for group studies. My rule of thumb is to limit interpolations to <20% of the data-- other researchers may suggest less is better.
The large motions introduce a second problem which is they may cut off results from parts of the head. This is due to the usual implicit mask used by SPM that computes voxel wise results only if all the data is available in the time series. A big head movement sometimes moves the head outside of some voxels, so data is lost there. ArtRepair solves this problem because of the interpolation method. Removing the artifact scans (such as the Nichols, or Powers papers) also avoids this problem. However, the methods (e.g. Lemieux) that add null regressors may lose coverage of the head because of this issue.
Best regards,
Paul
----- Original Message -----
From: "Bethany" <[log in to unmask]>
To: [log in to unmask]
Sent: Friday, July 24, 2015 10:38:05 AM
Subject: [SPM] ArtRepair Toolbox installation/Use
Hi All,
I've been having some trouble installing and using the ArtRepair(v5b) toolbox in SPM8 running in MATLAB R2014b.
I've placed the ArtRepair folder in the toolbox directory for SPM, and it comes up in the Toolbox drop down like the other toolboxes I've added, but when I select it, I receive this error:
Error: File: aREADMEArtRepair_v5b.m Line: 22 Column: 22
Expression or statement is incomplete or incorrect.
Error in spm (line 981)
evalin('base',xTB(i).prog);
Error while evaluating UIControl Callback
In the readme file, line 22 is a series of dashes (commenting them out only leads to another error on the next line). I admit, I am more familiar with R than MATLAB, so I'm not sure how to remedy this...
Have others encountered this error?
Thank you in advance!
Bethany Sussman
P.S. While on the subject, does anyone have experience using ArtRepair or other toolboxes/methods to look at movement sometimes around of 10-15 mm (usually in sporadic spikes)? I'm working with a pediatric clinical population that often gives me movement between 3-5mm, but every once and a while is more severely wiggly (to use the technical term). I was planning on starting with ArtRepair to see what I can get, but if someone has recommendations for tools for that degree of movement, I appreciate any input.
