There’s something I’m stuck on and I hope by posting here people can help me with this problem and potentially offer more insights for people who are in similar situations as I am.
In the online study that I am building, I’m presenting an audio (wav file) and a picture simultaneously to participants in each trial (I will refer to those types of trials as “normal trials” below).
However, I want to add in some silent “catch trials” where only the picture is presented—no sound will be presented on such trials. And I want to mix in those silent picture-only trials with the “normal trials” so that participants do not know which type of trial will come next. They will reply to both the silent trials and the “normal trials” with key presses.
Right now, I only have the “normal trials” set up because I am not sure how to add in the “silent trials”. Currently, the normal trials are presented as:
There’s a certain amount if jitter time between each trial. Both the picture and the audio are set to start at the Jitter time, and participants can make responses right after Jitter time starts. It looks like this in a routine:
Similarly, the picture (labelled as ‘image1’ above) and response start time (labelled as ‘key_resp1’ above) all start with $Jitter.
The routine is wrapped inside a loop, and the loop contains an excel file that specified which audio and picture files to present, as below:
However, the problem is, if I want to add in silent trials (as the third row in the picture above), I will put in the picture path under the column “Picture”, but what should I specify under the “Audio” column?
Any suggestions/insights would be very much appreciated. Thank you all!