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Dear Ramesh,

some first thoughts about your analysis:
1. By using an initial peak threshold of P<0.001 there survives one 
large cluster the cluster-level threshold FWE-corrected of P<0.05. 
Please check the SPM mail list for previous discussions about the use of 
cluster-level thresholds. In short: the initial peak-level threshold of 
P<0.001 allows the application of an additional (FWE-corrected) 
cluster-level threshold.
2. You can give the TFCE toolbox a try that combines peak- and 
cluster-levels
3. The estimated smoothness of about 18mm is surprisingly large for a 
Gaussian filtering with FWHM of 10mm. Have you used in the stat. model 
an absolute threshold of at least 0.1 to ensure that you only analyze 
gray matter?

Best,

Christian
________________________________________

Christian Gaser, Ph.D.
Professor of Computational Neuroscience/Neuroimaging
Biomagnetic Center
Structural Brain Mapping Group
Department of Neurology
Jena University Hospital
Am Klinikum 1, D-07747 Jena, Germany
Tel: ++49-3641-9325778 Fax:   ++49-3641-9325772
e-mail: [log in to unmask]
http://www.neuro.uni-jena.de

On 12 Dec 2017, at 17:54, Ramesh Babu wrote:

> Dear Expert,
>
> I did VBM analysis on two groups with n=40 in each by using CAT12 tool 
> in
> SPM. Please see the attached VBM result. Initially I kept p value as 
> 0.001
> uncorrected and got significant finding in some regions. In the VBM 
> result
> table at cluster level I found p value <0.05 for first cluster. But 
> when I
> change the significance level to 0.05 FWE corrected in SPM result 
> window, I
> am not getting any output (empty glass brain result).
> Could you please give me your suggestions to interpret and report the
> result?
>
> Additional details;
> Smooth = 10mm
> Nuisance co-variate - tiv, age, & sex
> K=175
>
> Thanks
> RB