using a t-contrast with +1 will show positve correlations only - a  
negative t-contrast (-1) will show the negative correlations and a  
F-contrast (1 or -1 doesn't matter) will show both


> Dear Sir or Madame,
> For several weeks I am trying to find the solution for the  
> following  problem. After functional connectivity analysis I made a  
> factorial  design to look at the results. I am trying to find out  
> how I can see  whether the results are positive or negatively  
> correlated with my  seed voxel. SPM5 only shows positive t-values.   
> Even when I make a  plot with my effect of interest I only see  
> positive values. Does  this mean that I only found positive  
> correlations? Is this the right  way to check whether the results I  
> found are positive or negatively  correlated with my seed voxel?
> I really hope you can help me.
> I hope to hear from you soon.
> Yours faithfully,

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