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How to register the temporal allocation of stimuli and responses in Psychopy?

I’m constructing a lexical decision task with the builder and I’m writing to ask whether it is possible to register the temporal alocation of stimuli and responses across trials. In Matlab there is a function called GetSecs. Is there something like GetSecs in the Psychopy?

Best Regards,
Marcelo.

Can you define exactly what you mean by that? You are presumably controlling the time of occurrence of your stimuli, and collecting responses, so both of these things should be recorded in the data automatically for you.

Hi Marcelo,

maybe core.Clock() is the function you’re looking for? It helped me record response times across trials in a similar situation.

Best
Torge

Hi, Michael. Thanks for responding.

Well, let me see if I can clarify my issue with and example.

Think of a semantic decision task that presents several sequences of stimulus pairings in the following way: fixation point -> prime stimulus -> inter-stimulus interval -> target stimulus -> question mark. Consider that primes are ‘cat’, ‘snail’, lion’ and targets are ‘pet’, ‘pest’, ‘beast’. I’m trying to figure out how to generate an output which shows in which moment of the task the stimuli were been preseted. For example, at 00:01:00, the prime was ‘snail’; at 00:01:015, the target was ‘pest’; at 00:01:20, the participant pressed key ‘y’, et cetera.

Hi, Torge.

I need more than just reaction times. I need outputs showing which stimuli was been presented in a given moment. I’ll give you the example I gave to Michael.

Think of a semantic decision task that presents several sequences of stimulus pairings in the following way: fixation point -> prime stimulus -> inter-stimulus interval -> target stimulus -> question mark. Consider that primes are ‘cat’, ‘snail’, lion’ and targets are ‘pet’, ‘pest’, ‘beast’. I’m trying to figure out how to generate an output which shows in which moment of the task the stimuli were been preseted. For example, at 00:01:00, the prime was ‘snail’; at 00:01:015, the target was ‘pest’; at 00:01:20, the participant pressed key ‘y’, et cetera.

I’m still puzzled here. You already control when the stimuli are presented, they don’t just pop up on screen of their own accord. So you already know when they were presented, and those times (if they were specified in a conditions file) should be automatically saved for you by Builder in your data file. Similarly, the reaction time is recorded automatically also.

Have you actually tried running a task and then inspected the data output?

Hi, Michael.

You’re right. The builder does it all for me. I was thinking that I had to insert extra commands to get all these information. I was thinking that Psychopy works the same as Matlab.
Thank you!