Gissian random field (GRF) in DPABI for multiple correction

Dear experts,

I used Gissian random field (GRF) in DPABI  for multiple correction when comparing rs FC maps differences between patient groups.

Forums:

Gissian random field for multiple correction

Dear experts,

I used Gissian random field (GRF) in DPABI  for multiple correction when comparing rs FC maps differences between patient groups.

However, a reviewer suggested "this method (GRF) is based upon the hypothesis that the spatial smoothness of BOLD signal in the whole brain is consistent and the distribution of the spatial autocorrelation function in accordance with specific curve. Practically, the BOLD data is hardly accord with the hypothesis".

How to Set thr in the image caculator?

Dear Dr Yan

         I have several problem which confuse me .

         1. How to set the thr in the image caclator. I gonna set a mask use the expression, (i1<thr)+(i2<thr). I have no idea about the definition of thr. I had ever used the number of Voxels(alpha sim correction) and thr in Viewer. But it doesn't work.

        2.It confuse me that there are many noises in the blank region. 

Forums:

smoothing, alff and reho

Dear Dr.Yan,

May I ask a simple but sounds stupid question? I know it should do reho before smoothing, but is it possible that calculate alff before smoothing as well? Why?

best

fish

Forums:

Mixed effect analysis

Dear experts

In a statistcal analysis of DPABI, a default setting of mixed effect analysis is 2X2. 

What if I want to use mixed effect analysis of DPABI with factors greater than 2? 

Best, Dong Woo 

Forums:

在Matlab的脚本中 启用并行

各位专家:

       请教各位老师,我在写matlab的一些小脚本时,运行速度很慢,请教各位老师,需要进行怎样编码/设置可以启动8核的并行计算(我用的32G内存的工作站,Matlab2011b) 多谢指教!

Forums:

Paired T-test in RS comparison

Dear Experts,

I am new to FSL and RS signal analysis, so I need a help to understand the methods and the results of a preliminary fcMRI study that my supervisor has been working through.

He wanted to test variation in connectivity within motor circuits at rest. It is a single group design with repeated measures, divided into three parts: baseline RS scan, task performance and control RS scan. The idea was to compare the two RS scans in order to see variation in connectivity after the task performance, thus expecting increase functional connectivity within motor circuits.

How to run DPARSFA on Sun Grid Engine

Dear DPARSFA list,

 

I am wondering how I can run DPARSFA with sun grid engine (SGE). Our server does not allow to run parallel processing so I was wondering if you could give advice on how I can run DPARSFA with SGE. 

 

Many thanks for your help.

 

Best wishes,

 

Forums:

Problem with running preprocessing

Hi there,

While attempting to run the preprocessing on the Demo Data from the fMRI course per the video instructions, I ran into a few issues. Upon hitting run, MatLab says it is launching a parallel pool to run my processing in, but also MatLab says no jobs are currently running. Additionally, it says that the parallel pool is busy, and this continues for hours, over 9 that is. I can't seem to find the file either of the altered data, so perhaps the process is just incomplete. What could be a potential problem? 

Thanks,

Zoe Dittman

Forums:

Setup for ancova with covariates

Hi,

I'm trying to set up an ANCOVA with covariates.  I have FD as one covarate and 4 groups (numbered 1, 2,3,4)

How do I set up the analysis.  Can I load in an FD.txt file and a file with groups listed as 1-4, or do I make a multicolumn file with 5 columns, or do I need a separate file for each group, as well as 1 for FD?  Also, how will I know from the output that the covariate has been removed from the data prior to the group F test being computed?

Thanks,

Matt

Forums:

Pages

Subscribe to Front page feed