Delayed response to keypress

vatsalthebest

Hello!

I have designed a very simple task on OS for my undergraduate students. They have lab class next week so its a bit urgent if someone can help me resolve this.

The task is a arrow flanker task. For making the experiment easier I have short pre practice sequence with four trails. I have keyboard response for responding. Whenever, there I press the dseignated key response it doesn't gets registered at the first time I have to press it again to get the response.

I am not sure how to solve this issue would be really great if someone can explain if I am doing something wrong.

@sebastiaan is this a software issue because I have seen this issue in older versions as well.

Thanks

Vatsal

Flanker_task.osexp

Fab

Hi @vatsalthebest,

That problem is typically the result of requesting two responses. This is indeed your case. In the pre-practice loop, you set the duration of new_sketchpad5 to "keypress" and then you have a keyoboard object taking a response again. Set the duration of the new_sketchpad5 slide to 0. That way it will display the target and executes the keyboard object right away.

Incidentally, you have a lot redundancy in your experiment. You could have used linked objects in the various sequences instead of creating distinct instances (that why, correcting an issue in one place would fix it in all sequences at the same time).

I also noticed that in other sequences, you set the duration of the target slides (Target_1 and Target_1_2) to 250. That means that your RTs measured from the subsequent keyboard obkects will not be measured from the target's onset. That is, if you present the target and the subject responds 360ms later, the RT you're measuring will come up as 160ms in your output. This is because you display the target for 250ms and only then starts taking a response. To fix this, set the duration of the target slides to 0.

Good luck,

Fabrice.

vatsalthebest

Hi @Fab

Thanks for your swift reply.

I have incorporated your changes and the issue I was facing was corrected. However, I have a doubt on adjusting the timings for target slides. As per the paradiagm the target is to be displayed for 250ms but if put 0 then I am not sure how I am controling the presentation time?

Could point me towards a specific section in the documentation or if you could just briefly explain?

Thanks

Vatsal

Fab

Hi @vatsalthebest,

If you'd like to have the target presentation limited to 250ms while the response registration starts with the target and keeps going, have a look at the coroutine object: https://osdoc.cogsci.nl/3.3/manual/structure/coroutines/

Your program contains quite a few redundancies and problems (e.g., your logger does not log individual RTs). You might want to take the time to follow the tutorials and check OS's documentation to get a better grasp of some of the basic features. in the long run, it'll make your task easier.

Hope this helps.

Fabrice.