Flicker paradigm problems

If this template helps then use it. If not then just delete and start from scratch.

OS: WIn 10
PsychoPy version (e.g. v2024.1.4):
**Standard Standalone? ** Yes
What are you trying to achieve?: A flicker paradigm/change detection task with pairs of images, each displayed for 240ms plus two fixations one before image 1 and a one before image 2, the pair must be repeated until a response is made or 60seconds elapses. After a response, then move to next trial recording accuracy and rt from first stimulus onset.

What did you try to make it work?: Tried learning code!! Badly.

What specifically went wrong when you tried that?: I cannot get it to repeat the pair of images until a response or 60seconds.

As usual I have gone through the forum for similar issues and not really got close.
condsPrac.xlsx (8.7 KB)
Jolie.psyexp (18.7 KB)

It’s also doing something really funky in resizing one of the images in the pair mid run even though I have checked sizes etc. I have no idea what that is all about!!

Start by deleting your loadStim routine and trialsLoading loop. They are trying to run your experiment in code.

The simple (low code) way would be to have one routine with five components (fix1, image1, fix2, image2 and key_resp). Give them appropriate start times. Give the trials loop the correct number of iterations to add up to 60 seconds. Point the trials_2 loop at your spreadsheet.

Ok, thanks. Done that.

It sort of works. The keyboard response should end the iteration if a response is provided, but it doesn’t. The presentation of the pair continues for the whole duration, irrespective of a response.

Two options.

  1. Break the loop with trials.finished = True if there is a response.
  2. Use Each Frame code to loop the images within a single routine, as per my RSVP online demo.