I am working on inter-subject correlation and to verify the computations, I would like to view the activation in the region of visual cortex vs time. That could be done using 4D trace in MRIcron, using the ROI and event onset time files. But the intensity graph shown does not specify the voxel or slice number. Is it because it is plotting the average over the ROI? I am not able to find what it plots and want to confirm it. 

In another case, if there is no ROI selected, then it only shows the center voxel. Is there a way to change the voxel to be viewed?

Thank you

Yes, it plots the average of the ROI, or if no ROI is loaded it displays the data from the selected voxel.