Randomly changing the spatial position and visual items
I am working on a spatial perception project. Part of the task includes display of letters in 'A B C D' format while performing a concurrent timing task. Later I want to test the accuracy of the memory for the displayed items in this format ' * B * * '. What would be the most efficent strategy in the testing session for randomly changing the place of the to be displayed letter and creating the right and wrong options ? (eg. ' * B * * '-> True; ' * G * * ' -> False)
Note: I use variables Letter_1-2-3-4 for the display part.
Thanks in advance,