Hi,
A friend from our schools psychology department wants to use PD and GEM for an experiment. Here is his question and attached is the example patch. We need you help on this. Thanks.
OK, this is the patch that I'm going to use to conduct a research on cross-modal interactions in human perception. I'd be happy to fill anyone in on the topic because generally human cognition is fun to poke around.
So the required stimuli are a "beep" sound (which is a 3.5khz sine with 7 ms duration) and a "flash" (which is basically a white circle visible only for 20ms).
The problem is, it is very hard for an object to "flash" with this short duration. If you look at the patch you'll see that less than 50% of the trials do not produce anything.
I have to come up with a workaround to this and I thought maybe if I can syncronize the onset of the flash with the refreshing rate, I can at least make the disk visible for all of the trials. I can sacrifice the precision in terms of duration but that is bound to happen I guess.
I made this patch on windows with my laptop with a poor refreshing rate and another laptop with Macosx did not perform any better on the task(they are both 60hz screens). But I am guessing that a non-lcd monitor may do better? Any comments or suggestions on this?
Relevant information on the stimuli and the procedure can be found in this reference article for those of you who are interested "Visual illusion induced by sound" by Ladan Shamsa, Yukiyasu Kamitanib, Shinsuke Shimojoa.
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