[open] Interstimulus Interval (ISI)

noamkarsh

Hello,
I am trying to create a fixed ISI for my task that is sensitive to participants response time. For example, I have tried to set the stimulus duration by defining it as "1000-avg_rt" so that the stimulus duration will be a function of participants response time (faster response leads to longer stimulus duration) but it didnt work.
I will appreciate any suggestions how to create a fixed ISI that can overcome participants response time.
thanks
Noam

lvanderlinden

Hi Noam,

The best way to achieve this is to insert a variable delay immediately after collecting the response. By doing so, the total delay (response_time + delay) is always the same.

The delay would be, for example, 2000 ms - response_time. You could do this by inserting an inline_script item right after the keyboard_response, with the following code in the Run phase tab:

fixed_dur = 2000
self.sleep(fixed_dur - self.get("response_time"))

Does this make sense?

Best,

Lotje