Hi!
I'm programming a Go / No-go task where participants respond to frequent targets by pressing the space bar (Go trials) and withhold a response to infrequent targets (No-go trials). To make sure participants understand the instructions and are capable of performing the task adequately, I'm starting with a practice round where they get feedback on errors and slow responses. For errors on No-go trials and slow responses on Go trial this has been no problem at all. My problem lies in displaying an error-message also when participants don't respond to a go trial. I can't get this to work. I'd be thankful for your help.
This is what I did. On NoGo trials, error feedback ( = trial.wrong) is given when participants make a response.
<trial NoGo>
/trialduration = 1150
/posttrialpause = 100
/stimulustimes = [1=targetp; 250=fixation]
/correctresponse = (noresponse)
/validresponse = (57, noresponse)
/responseinterrupt = trial
/ branch = [if (trial.NoGo.response == 57) trial.wrong]
</trial>
On Go trials, "too slow" feedback ( = trial.slow) is given when participants make a response above 600 ms. The same feedback should be shown when they make no response. For some reason this doesn't work. Here is my code for the trial and below some alternatives I tried.
<trial Go>
/trialduration = 1150
/posttrialpause = 100
/stimulustimes = [1=nontargetp; 250=fixation]
/correctresponse = (57)
/validresponse = (57, noresponse)
/responseinterrupt = trial
/ branch = [if (trial.Go.latency > 600) trial.slow]
/ branch = [if (trial.Go.response != 57) trial.slow]
</trial>
I tried out if the problem lies in the multiple branching. This is not the case. No feedback is shown even when I use conditional branching only based on the response alone, like this:
<trial Go>
/trialduration = 1150
/posttrialpause = 100
/stimulustimes = [1=nontargetp; 250=fixation]
/correctresponse = (57)
/validresponse = (57, noresponse)
/responseinterrupt = trial
/ branch = [if (trial.Go.response != 57) trial.slow]
</trial>
I also tried alternatives such as
/ branch = [if (trial.Go.correct == 0) trial.slow]
or
/ branch = [if (trial.Go.latency = 1150) trial.slow]
With the last line, I get an error message. With any of the other lines, the program runs, but doesn't show the feedback for response omissions.
Thanks in advance for your suggestions!