Synchronize random trials?

I have designed a simple minimal pair test in which the subject will see and image file with two words on it (I had to use image files due to a lack of Arabic support), then a brief ISI and then they hear one of the two words spoken. I would like to randomize the presentation of the stimuli, but when I do that the images and sound files are no longer synchronized, so obviously that won’t work. I assume there must be an easy fix for this, but I haven’t been able to figure it out.
Any ideas?

It sounds like you might be randomizing the events in the trial. Instead I suggest randomizing the trials within the block, which is done on the block level.

Thanks! That did the trick.

Synchronising Random trials again!


I’m really stuck on something concerning stimuli randomization. I understand that you want to randomise the trials (which I know you do at the block level). However, I want to present pairs of events but they must be RANDOMLY paired:

a)A photo (participant responds to a question under the photo)
b)A face (another question the participant has to respond to)

Then it has to be repeated.

The events have to be in the order stated above and they have to be randomly paired (so that each time a photo appears, any face comes after it.

I have randomised the blocks already (so the trials are random), but within each trial I have had to programme the stimuli into sets that are already paired just to keep the order of a) before b). This takes away the randomisation of events!

What should I do?


Please see: