Batuhan Bozkurt wrote:
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.
hmm,
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.
the first thing i noticed is that you are running Gem with the default framerate, which is 20 fps (50ms!) there is plenty of time where you can trigger the flash right after a render-cycle and the flash will disappear before the next one.
so the first thing you ought to do is use a higher framerate, best choice will be the same rate as your monitor (60Hz): [gemwin 60]
it's hard to display a flash for 10ms if every frame stays there for 50ms... :-)
the next thing is to synchronize your trigger events with the gem-rendering.
just insert a [t a b] object to the gemchain (e.g. [gemhead]), the 2nd outlet will band everytime the gemchain is executed (the actual rendering (buffer swapping) is done immediately after all gemheads have returned, which is 0 logical time after the bang (but some microsecs real time)
fmadsr. IOhannes