Displaying images in a non-blocked fashion

I have been using media for a few months now and am becoming familiar with the software, however, I did have a question. If I want to show my participants a total of 12 pictures, can media lab randomly display 8 of the pictures for the first part of the experiment, and for the recognition test, can it randomly display the 4 pictures from the total 12 that it did not display before? In the sense, I am trying to have it sample without replacement. Is that possible to do in media lab?