how to create a 2-back test (case 22831)

[fadi]

I am trying to create a 2-back test using images. I have the directrt 2010 version and have read the tutorial, but I am having a hard time coding. This is my first time working on a computer program and am confused. Is there any way someone could talk me through it? I am testing for reaction time.

[jason_reed]

Could you please give me some specific details about what exactly you need your two-back task to do in DirectRT? That is, what should a typical trial of this task look like and what do you need your participants to do.

What specifically are you having trouble programming DirectRT to do?

Please also tell me the full version number (i.e., 20xx.x.xxx) of your copy of DirectRT. You can find it by opening DirectRT and selecting Help>About DirectRT from the main menu bar.

[fadi]

Between each presented image, I want to be able to show whether the answer is correct or not. I found this a template excel sheet online and included my photos. it is working, yet would you explain to me the condition and critical columns.. Would it be easier to analyze data if you code in a certain way - same with the time column?
Directrt Version 2012.4.0.166

[jason_reed]

Could you please explain what you mean by "critical columns?"

[fadi]

Ignore my last question. The critical column is just to help show the matches and nonmatches - it just helps me with data. I have updated my excel sheet. At this point, I am facing problems with timing everything. How will I be able to present the stimuli for a certain amount of time rather than present it until there is a response? Also, I want to shorten the amount of time that the "feedback" is presented. Would you be able to help me?

[fadi]

The correct Excel sheet is this one****

[jason_reed]

Thanks for the file. Based on what you have there, it appears that for your trials with a key press you also want to control the amount of time that the stimulus is on the screen but still allow for these key presses to happen. If that is correct, take a look at the section named "Fixed Response Window/Stimulus Duration with an RT" here in the DirectRT manual: http://www.empirisoft.com/directrt/help/directrt_minmax_setting_rt_limits.htm. You will put the amount of time you want the stimulus to stay on the screen as the maximum value for the MinMax cell with the same number in the styles.drt file as the one in your trial.csv file.

To control the amount of time that the feedback in the last two rows of your trial.csv file stays on screen, simply put the number of milliseconds in the time cell of those rows. Right now, you have it programmed to keep the feedback onscreen for 2000 milliseconds.

[fadi]

Thank you! That was helpful. It worked out. One last thing, if it takes a little while for me to respond to the stimulus, a "Please respond faster" pops out on the screen. How could I remove that?

[jason_reed]

To remove the "Please respond faster" message, set the minimum value of the MinMax column for that style number in the styles.drt file to 0 (see this section of the DirectRT manual: http://www.empirisoft.com/directrt/help/directrt_messages.htm)