Help: filter for successful trials.

Hey there, 

I am in the process of doing a gPPI analysis with Conn. It is a stop signal task where there is a go and a stop condition. When I automatically upload the .tsv files, there are both successful and unsuccessful trials. Can I only filter the successful ones with Conn? If so, how does that work?
Or do I have to write a script for the tsv files first and take out the unsuccessful trials?