Hi, I'm trying to display some magazine ads as a stimulus. I have a pool of 16 filler ads from which I'd like to select 8 at random to show and a pool of 8 target ads from which I'd like to select 4 at random to show.

The complication is that I'd also like to set a certain amount of time that the ad is displayed on the screen before enabling the space bar for Ps to move on. I know how to get the ads to display randomly in directRT (using the identifier "$") and how to set a particular display time before allowing Ps to move on in MediaLab (setting parameter as "d-30" to make sure it's displayed for 30 seconds). But, is there a way that I can use MediaLab or DirectRT to both the set display time AND choose the stim randomly?

In other words, I'd like an ad to be chosen randomly from the pool (well 4 from one pool and 8 from another pool), displayed for 30 seconds, and then activate the space bar for Ps to move onto the next randomly chosen ad.

Thanks for your help!
Missie