[solved] Difference between response_time and response_time_keyboard_response

kwolfs

Dear reader,

I have programmed an IAT in OpenSesame, and truly love this open source program. There is some discrepancy between the logger variables "response_time" and "response_time_keyboard_response". When I view the logger after running the experiment I noticed the values sometimes differ between response_time and response_time_keyboard_response. This only (and always) happens if participants made an error and the variable "correct" is set to 0. Sometimes it is only a small gap (e.g. 772 vs 621) but sometimes a large gap between the two can be observed (e.g. 823 vs 386).

Does anybody know why these two logger variables are not the same value when participants make an error (correct = 0) and what exactly is the difference between response_time and "response_time_keyboard_response"?

Kind regards.

Kenny Wolfs

lvanderlinden

Hi Kenny,

The variable 'response_time_keyboard_response' contains the RT of the key press collected by the keyboard_response item called 'keyboard_response'. Therefore, this is probably your variable of interest, also for the incorrect responses.

The variable 'response_time' contains the RT of the most-recently-collected response (e.g. another keypress or a mouse click). As you mentioned in your previous post, you provide participants with feedback only after a mistake. Therefore, if participants make another key press in response to the feedback display, on those trials the value of the 'response_time' will represent the RT of this press.

So, in short, I would advise you to use the 'response_time_keyboard_response' as your dependent variable.

Does this make sense?

Best,

Lotje

kwolfs

Hi Lotje,

Thanks a lot for this concise information, it's all very clear to me now.

King regards,
Kenny