Thanks. That seems to have solved the problem. There's still some indication of electrical noise in that the green bar in the voice response utility flickers back and forth a bit even when there's absolutely no vocal input, but the sensitivity can be moved far enough along that only actual voice responses will trigger an RT.
However, the RTs recorded are a lot longer than they should be (well over 1000 ms) and I think my input file is problematic. I want a fixation cross to be up there for 750 ms before a word stim appears for 160ms and the fixation cross to stay for at least 250 ms after the word stim disappears, with a vocal RT to the subject's response to the word stimulus, making sure that to record the whole sound file of their word response. I had a hard time figuring out how to do this, but the input file I came up with is:
[edited a bit here for formatting by moderator]
On each trial, three combinations of stim, loc and time as follows:
Code:
~+ 0,0,1 750
~CLOUDY <3> 1025,575,0 160
~+ <1> 0,0,1 RT:aud,rec,-1500
Would appreciate help on how to correct the input file accordingly so that the RTs will be accurate. Thanks.