Setting 2 seperate duration times

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LizaM

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Dec 18, 2009, 11:15:02 AM12/18/09
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Hello,

I have an experiment which runs 32 lists as facial image sequnces -
the participant has to press space when the eyes within the faces
appear to be no longer looking at them. Each list needs to reapeat
twice with each image in the sequence displayed for 200ms on one
viewing and 300ms on the other viewing - these should not be
sequential, ie seq 1 may have 300 ms on first view and 200 on 2nd, seq
2 may be the other way round etc. The lists need to be displayed in a
random order but one view must be 200ms and one 300ms. I have made
the duration on the image display object into a variable which is
selected from a list nested inside bloclk list - my question is how do
I ensure that one view of the seq is at 300ms and one at 200ms whilst
preserving the random order of sequences?

Many thanks for any help!

Liza

LizaM

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Dec 18, 2009, 11:41:47 AM12/18/09
to E-Prime
Just worked it out! Repeated the Procedures that run the Image seq
lists in the Blocklist twice, created an attribute called timeduartion
in that list, gave each a value of 200 for the first lot and 300 for
the repeats, used that as the variable in the Image Display duration,
set the blocklist to select randomly and bingo! It works! I think it
was documenting the problem here that helped though :)
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