[Mne_analysis] permutation cluster analysis only shows significant results on right hemisphere

[Xing Tian]

Can anyone who is familiar with permutation cluster analysis help me on 
this?
I used 'permutation_cluster_1samp_test' in MNE python on my data and 
only the right hemisphere showed significant results. Is it possible 
that the effects on right hemisphere is so strong that the weaker 
effects on the left was washed out by the permutation significant test? 
Is so, can I run the permutation cluster analysis for each hemisphere 
separately?

Thanks,
Xing