Problems with feedback timing

Phineas_Gaze

Hello, I am running and experiment and I was trying to ensure that there was an ITI at the start of a trial of 500 ms (which it does) a guess/lure length of 7000 ms (which it also does) and then feedback presented for 5000ms. The feedback is what I'm having trouble getting to be 5000 ms. I believe it's down to the prepare and run nature of OpenSesame, and I attempted to solve this a bit with the supertiming inline script. However, the duration of feedback still varies, being up to 200-300 ms off on some trials. I'd like to know if solving this is possible.

Below is a copy or the prepare and run phase of the script

# prepstart

var.prepstart = self.time()

exp.set("feedbackdur",0)

# calculate the preparation time

preptime = int(self.time() - exp.prepstart)

exp.set("feedbackdur", int((4995 - preptime)))

#import random

# timing settings (mean ITI and jitter)

#ITI = 500

#jitter = 10

# calculate the actual pausing time (including jitter)

#pausedur = random.randint((ITI - preptime) - jitter, (ITI - preptime) + jitter)

# pause!

#self.sleep(pausedur)

eduard

Hi,

I don't get your code. If the feedback is very complex (many text elements, a lot of computations, etc.) it might cause delays, but I hardly have seen it before. Can you share (a simplified version of) your experiment with us? Then we can have a closer look.

Thanks,

Eduard