ROI definition

I am trying to run a correlation for a group of subjects at once. I have the timecourses for my seed ROI in text files. It seems however, that the option for defining voxelwise ROIs using text files only allows one file to be loaded at a time. Is it possible to load multiple text files, corresponding to the seed timecourses for each subject?
Thanks for your help,

You just can choose one file at a time if you use the GUI of REST.
But you can read the fc.m and wrote a program to call it.

Dear Alex,
DPARSF ( may help you to do multiple time course Funtional Connectivity analysis, although it's a software supply one-stop service for Resting-State fMRI analysis.