Re: [Freesurfer] Normalization of external regressors

2017-02-15 Thread Douglas N Greve
It depends a bit on whether they are nuisance regressors or not. If they are not nuisance regs, then I would be very careful normalizing them because it could make the regression coefficients hard to interpret when comparing across subjects (you would probably just use the same scale for all su

Re: [Freesurfer] Normalization for functional connectivity

2016-05-11 Thread Sahil Bajaj
I already used this argument during preprocessing. According to the explanation here: http://surfer.nmr.mgh.harvard.edu/fswiki/FsFastFunctionalConnectivityWalkthrough in step-3, time-series data are sampled onto fsaverage then I am not sure why 2nd-level analysis is showing me significant self conn

Re: [Freesurfer] Normalization for functional connectivity

2016-05-11 Thread Martin Juneja
I would suggest you to check if preproc is done using the argument -mni-305-2mm. On Wed, May 11, 2016 at 12:48 PM, Sahil Bajaj wrote: > Hi Dr. Greve, > > This works for me if I define seeds into subject-wise anatomical space. > > Now, location of seed regions across subjects might differ because

Re: [Freesurfer] Normalization for functional connectivity

2016-05-11 Thread Sahil Bajaj
Hi Dr. Greve, This works for me if I define seeds into subject-wise anatomical space. Now, location of seed regions across subjects might differ because these are defined in subject-wise anatomical space. Hence subject-wise connectivity maps are generated from subject-wise seeds but these can be

Re: [Freesurfer] Normalization for functional connectivity

2016-05-10 Thread Douglas N Greve
You should map the ROI into the individual subject's anatomical space, the specify the ROI when you configure the seed (eg, fcseed-config -seg ROI.mgz -segid 1 ...) On 05/10/2016 10:37 AM, Sahil Bajaj wrote: > Hello all, > > I am interested in importing some seed regions which are in MNI space

Re: [Freesurfer] normalization of hippocampal volume

2015-10-22 Thread Douglas N Greve
I'm not sure what you mean by either of those options. can you explain? On 10/22/2015 04:18 AM, geschwind2013 wrote: > Hi, FS Experts, > > I’m using version 5.3 and have performed hippo-subfields analysis. > > To perform the statistics, shall I get the normalized volumes of each > hippo-subfield

Re: [Freesurfer] -normalization all black

2014-07-03 Thread Louis Nicholas Vinke
Hi Teo, You might just need to adjust the contrast/brightness settings when viewing the volume in freeview. If you move your mouse around do any non-zero values appear in the bottom right voxel info panel? The T1.mgz for bert should be 4.6mb, so you can see if what you have matches that. O

Re: [Freesurfer] normalization problem (versions 5.1 and 5.3)

2014-05-23 Thread Bruce Fischl
Hi Maia it's hard to say since I don't really know what steps worked in 5.3 or why vs. 5.1. I guess you could try starting from after the normalization in 5.1 and seeing if they go through the rest of recon-all Bruce On Tue, 20 May 2014, Maia Pujara wrote: Thanks for your response, Bruce.

Re: [Freesurfer] normalization problem (versions 5.1 and 5.3)

2014-05-20 Thread Maia Pujara
Thanks for your response, Bruce. Since we would rather not re-run all 200+ subjects through version 5.3, would it be possible, for the sake of keeping things consistent, to add any flags to recon-all using version 5.1, to be able to include the remaining 35 subjects into our analysis? On Fri, Apr

Re: [Freesurfer] normalization problem (versions 5.1 and 5.3)

2014-05-15 Thread Bruce Fischl
Hi Maia Yes, it's possible. We've made a bunch of improvements Bruce > On May 15, 2014, at 1:13 PM, Maia Pujara wrote: > > To follow up, it makes sense that the noise might be an issue, but it seems > like version 5.3 creates the surfaces just fine regardless of the noise, so > I'm wondering i

Re: [Freesurfer] normalization problem (versions 5.1 and 5.3)

2014-05-15 Thread Maia Pujara
To follow up, it makes sense that the noise might be an issue, but it seems like version 5.3 creates the surfaces just fine regardless of the noise, so I'm wondering if perhaps there has been a chance in preprocessing before the end of the T1.mgz computation that solves the problem. Would there ha

Re: [Freesurfer] normalization problem (versions 5.1 and 5.3)

2014-04-28 Thread Bruce Fischl
Hi Maia it's hard to know from just these images, but I wonder whether the high background noise level at the top of the image is messing up 5.1. You might try cropping that out and seeing if things get better. cheers Bruce On Fri, 25 Apr 2014, Maia Pujara wrote: Hi all, After running 200

Re: [Freesurfer] Normalization Errors?

2013-05-08 Thread Gonzalo Iribarne
Hi Bruce, The nu.mgz volume is has the most pronounced contrast between grey and white matter. The orig.mgz volume blurs the distinction between white/grey matter to a point where it is difficult to tell by visually inspecting it. The grey matter in the orig.mgz volume has values as high as 147-15

Re: [Freesurfer] Normalization Errors?

2013-05-08 Thread Bruce Fischl
Hi Gonzalo it's hard to tell from just that image. What does it look like before normalization (e.g. the nu.mgz or orig.mgz)? Is there gray/white contrast there? cheers Bruce On Wed, 8 May 2013, Gonzalo Iribarne wrote: > Hello Freesurfers, > There are some areas of grey and white matter that

Re: [Freesurfer] Normalization

2012-10-06 Thread Ana Arruda
It's clear now. Thank you very much. And you're right about manual ICV, I have only two images for each patient with the area of the biggest plan in the brain, commissural area. Best regards, Ana Arruda ___ Freesurfer mailing list Freesurfer@nmr.mgh.ha

Re: [Freesurfer] Normalization

2012-10-06 Thread Martin Reuter
Hi Ana, if you work on a study comparing groups or age effects, that analyzes hippocampal volume, then you would usually normalize that volume. People have different head sizes and therefore differently sized hippocampi. To remove headsize differences researchers often normalize voumes by ICV.

Re: [Freesurfer] Normalization

2012-10-06 Thread Ana Arruda
Thanks a lot Martin. I really get confused about normalization. I've already done the comparisons and the values between methods, as you said, are different. Although I haven't understood why, in this case, I don't have to normalize. My advisor told me to normalize all the brain values from the pa

Re: [Freesurfer] Normalization

2012-10-06 Thread Martin Reuter
Hi Ana, when comparing to manual labels or other segmentation methods you do not need to normalize. But other methods and even manual segmentations may follow a different protocol, so it can be expected that some method gives consistently different (e.g. smaller) values. ICV in FreeSurfer is c

Re: [Freesurfer] normalization

2012-08-17 Thread Douglas N Greve
Not really, but you might want to account for total brain size or (estimated) ICV. doug On 08/17/2012 02:13 PM, Alfredo Damasceno wrote: > Dear freesurfers, > > > Do I need to normalize volumes (MNI space or Tailarach) from > aseg.stats and aparc.stats before entering data in another statistical

Re: [Freesurfer] -normalization error

2008-09-24 Thread Bruce Fischl
Hi Jeff, I've seen this happen before with the N3 stuff where it reduces the image intensities so much that you start losing dynamic range. Not sure what causes it, but you could cp orig.mgz to nu.mgz and run from there forward. cheers, Bruce On Wed, 24 Sep 2008, Jeff Sadino wrote: Hello

Re: [Freesurfer] Normalization of mris_anatomical_stats

2005-12-08 Thread Bruce Fischl
Hi Glenn, we have some estimated total intracranial volume (eTIV) in the new stuff using something that Randy Buckner showed recently - the determinant of the tal transform is predictive of TIV. Should be out soon. It's not clear however that thickness needs to be corrected by it. The MNI fol

Re: [Freesurfer] Normalization of mris_anatomical_stats

2005-12-08 Thread Bruce Fischl
you mean by ICV? No, although in our new versions we compute ICV/TIV. Do you mean volume labels or surface labels? Volume of volume labels can be computed with mri_label_volume, surfaces can be given to mris_anatomical_stats -l cheers, Bruce On Thu, 8 Dec 2005, Glenn Lawyer wrote: Hi, W

RE: [Freesurfer] Normalization problem

2005-11-21 Thread Fornito, Alexander
Cc: freesurfer@nmr.mgh.harvard.edu Subject: Re: [Freesurfer] Normalization problem Hi Martin, we're looking into it - it's probably a bug in recon-all. Bruce On Mon, 21 Nov 2005, Martin Ystad wrote: > I'm working on the latest developmental release for Rh. 9. and I'm &g

Re: [Freesurfer] Normalization problem

2005-11-21 Thread Bruce Fischl
Hi Martin, we're looking into it - it's probably a bug in recon-all. Bruce On Mon, 21 Nov 2005, Martin Ystad wrote: I'm working on the latest developmental release for Rh. 9. and I'm having problems with the normalization procedures on my datasets. My datasets have large intensity inhomogene

Re: [Freesurfer] normalization failed

2005-01-12 Thread Joongnam Yang
Hi, I am having trouble removing the pons with recon-all -stage1 -pons-xyz. I've tried five pons coords, unsuccessfully. When you move the mouse location in the sagittal, horizontal, and coronal images, the slice numbers change. When I get the talairach coords for the pons, should the slice numbe

Re: [Freesurfer] normalization failed

2005-01-07 Thread Joongnam Yang
Hi, For one subject's data, "process volume" didn't get the skull stripped. The skull was there intact in "brain" volumes. To correct it, I used "expert preferences" and used "don't use watershed analyze", which led to most of the skull removed in "brain" volumes. But still there are pieces of th

Re: [Freesurfer] normalization failed

2005-01-06 Thread Doug Greve
You can tell recon-all not to touch the talairach.xfm file by adding -notalairaach to the command-line doug On Thu, 6 Jan 2005, Joongnam Yang wrote: Thanks Bruce, How would I specify the new talairach.xfm in the run of recon-all -stage1. If I copy the new file into the usual /mri/transforms directo

Re: [Freesurfer] normalization failed

2005-01-06 Thread Joongnam Yang
Thanks Bruce, How would I specify the new talairach.xfm in the run of recon-all -stage1. If I copy the new file into the usual /mri/transforms directory, it's overwritten during the recon-all process. Comments are appreciated. Nam. >>> Bruce Fischl <[EMAIL PROTECTED]> 01/06/05 4:55 PM >>> chec

Re: [Freesurfer] normalization failed

2005-01-06 Thread Bruce Fischl
check the talairach transform On Thu, 6 Jan 2005, Joongnam Yang wrote: Hi, During recon-all -stage1 running, I got the following error. ... MRInormalize: could not find any valid peaks No such file or directory mri_normalize: normalization failed No such file or directory ERROR: mri_normalize e