I'm looking to measure the time to complete the whole task of matching 6 pairs of images and the #of invalid matches. I want to know if direct rt can place two of each image file randomly on a grid and allow the subject to click and find pairs of images. Im also interested I the number if times a subject clicks on an image without finding it's match (but this is least important). 
I'm testing the difference between rts when  the level of detail in sets of images vary. I will be using the same images over 3 trials but in one they will be black silhouettes, next just black outlines, third will be full color. 

Jesse