Millisecond Forums

The values in /stimulustimes are *milliseconds*, i.e., you're presenting the audio at 20 and 30 milliseconds into the trial, not 20 and 30 *seconds*.

Well, I'll be damned ... that just might be the most obvious solution to a "problem" .. thanks!

Sometimes a fresh set of eyes helps -- things like these are easy to miss after staring at code for hours. :)

alas, it's not ready to be put to rest. I have one more creeping concern --
There are two general types of sound stimuli: non-repeating (18 different files to randomly select) and repeating (only one file). In repeated.videos trials I want the one sound stimulus to play at 10000 and repeated again at 30000; in the non-repeated.videos trials I want two different sound stimuli (randomly selected from the pool of 18) to come on, again, one at 10000 and another at 30000. Right now, in the non-repeated trials, the same sound file plays twice, rather than two different ones.  And in the repeated trials, it only plays once, at 10000, but not again at 30000.
I played around with different settings of the /select and /selectionrates functions, but same thing happens... here's the code:


Thanks!

###General purpose text and stimulus elements ###

<sound audioinstruction.nonrepeated>
/ items = AudioInstructionListNonRepeated
/ select = noreplacenorepeat
/ selectionrate = always
</sound>

<sound audioinstruction.repeated>
/ items = AudioInstructionListRepeated
/ select = replace
/ selectionrate = always
</sound>

###Trials ###

<trial repeated.videos>
/ stimulustimes = [0 = videoclip; 10000= audioinstruction.repeated; 20000 = audioinstruction.repeated]
/ validresponse = (anyresponse)
/ timeout = 40000
/ posttrialpause = 1000
</trial>

<trial nonrepeated.videos>
/ stimulustimes = [0 = videoclip; 10000 = audioinstruction.nonrepeated; 30000 = audioinstruction.nonrepeated]
/ validresponse = (anyresponse)
/ timeout = 40000
/ posttrialpause = 1000
</trial>

###Blocks###

<block block.repeated>
/ trials = [1=repeated.videos; 2=emotionratings]
</block>

<block block.nonrepeated>
/ trials = [1=nonrepeated.videos; 2=emotionratings]
</block>

<sound audioinstruction.nonrepeated>
/ items = AudioInstructionListNonRepeated
/ select = noreplacenorepeat
/ selectionrate = always
</sound>

That won't work -- it's not how stimulus elements (are supposed to) behave. You need two <sound> elements sampling from the same item pool.

<sound audioinstruction.nonrepeated1>
/ items = AudioInstructionListNonRepeated
/ select = list.nonrepeatedlist.nextindex
</sound>

<sound audioinstruction.nonrepeated2>
/ items = AudioInstructionListNonRepeated
/ select = list.nonrepeatedlist.nextindex
</sound>

<list nonrepeatedlist>
...
/ selectionrate = always
</list>

<trial nonrepeated.videos>
/ stimulustimes = [0 = videoclip; 10000 = audioinstruction.nonrepeated1; 30000 = audioinstruction.nonrepeated2]
/ validresponse = (anyresponse)
/ timeout = 40000
/ posttrialpause = 1000
</trial>