Stop-Signal task

[Ana_Maria_Flps]

Hi, everyone. Quick question: I am programming a stop-signal task, so in some cases I do not want the participants to press any keys to respond. That means that the correct answer is pressing no keys. How can I put that on my excel file? Thanks ?)

[4d4c]

Have you tried the solutions from this previous post?

No response a correct response

Thank you so much! Very much appreciated! Sorry if I kept asking you. It’s because I’m new to this software. Thanks again!

[dvbridges]

Hi @Ana_Maria_Flps. Attached is a simple stop-signal task - respond using space bar for white triangles only. In this task, the correct responses are stored in the conditions excel file under the corrAns column. Correct answers are defined in the keyboard component as a variable e.g., $corrAns, where None defines the correct answer for red triangles. Written in version 1.90.

stopSignal.psyexp (6.1 KB)
stopSignal.xlsx (8.7 KB)

[Ana_Maria_Flps]

Thank you very much!!!

[Ana_Maria_Flps]

Hi, everyone. Me again. Quick question still concerning the SSGNG.

I need to insert sounds (the stop signal) only on stop trials. However, I have an excel file with all my conditions (go, no go and stop signal). Is it possible that I insert the sound only for the stop signal trials? Does anyone have an example of how I could do that? Or maybe if anyone has an example of a go-no-go/stop signal task, where go trials become stop trials, could it please be sent to me? I don’t mind if it is visual and not by sound. Many thanks everyone

[Michael]

You can make the execution of routines conditional on some variable, e.g.

Random selection of stimuli without repeating in different blocks

Hi David, Welcome along… Well, below is a quick code snippet to show you how a tiny bit of Python can go a long way… You don’t need to break your trials into blocks. The easiest arrangement to have here is a single loop surrounding your trial routine so that it will run all 96 trials in random order. What you can then have is a pause routine that interrupts that single loop, but only on trials 32 and 64. i.e. insert a new routine. Just put a text stimulus on it saying something like “Take …

[Ana_Maria_Flps]

Many thanks! But what if I do not have the number of the trials, since my stop trials are random? Can I put something like: "if stop trials = sound? Is psychopy able to recognise stop trials from my excel file and add sounds to it?

[Michael]

@Ana_Maria_Flps

But what if I do not have the number of the trials, since my stop trials are random?

Yes, that was just an example of the technique, but you can use whatever test is appropriate to your relevant variables. We don’t know what it is called or what it holds, so amend something like this as required:

if your_trial_type_variable != 'stop':
    continueRoutine = False

[Ana_Maria_Flps]

Thanks!!!

[george98]

Hi, thanks for sharing this. I’m completely new to PsychoPy and don’t know how to implement what you shared in psychopy. Any help on how and where I’d use this would be great.

[Michael]

Hi, you should create a new topic, and give details of exactly what you want to do and what the stumbling block is – at the moment, this question is too broad to get a useful answer.