dot probe task

[Paul]

Hello. Thank you for accepting me to the group.

I am a first time user of e-prime and I'm finding it rather difficult to get my head around! I hope it's not beyond the protocol to ask for very basic help to build my experiment.

We are trying to partially replicate Buechner, V. L., Maier, M. A., Lichtenfeld, S., & Schwarz, S. (2014). Red-take a closer look. PloS one, 9(9), e108111 link: http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0108111 

The above experiment was itself created with eprime.

Essentially we want to present a face with an initial stimulus of an image (a face overlaid with colour, approx 40 different images), followed by a dot probe task. I have followed basic tutorials but I am very unsure about many things, and I don't know how to begin designing our experiment. For example: I don't know what objects to use for the image, or for the dot probe task. Alternately it seems I can use ImageDisplay, Slide, FeedBackDisplay? I don't know which one is best. However for each of those I don't know how to connect the stimuli (both the target image and the dot probe are stmuli, I suppose) to the items in the TrialList (I've managed to do a triallist at least, though I don't know if I've done it correctly), or how to upload/add the stimuli themselves. 

I also don't know how to configure the attributes or the properties to ensure that things are positioned and presented correctly. For example: we want the image to be in a medium box and to be positioned randomly in a quadrant of the screen, and the same for the dot probe shape appearing straight after. The image is to be for 250ms, the dot probe shape infinite until a key is pressed. Between the two stimuli should be a delay of 100ms (a separate object??). While I think I can program the duration of the stimuli, I certainly don't know how to program the random positioning.

There are to be 80 proper trials, and 20 practise trials. A proper trial would contain 16 attentional shift trails, and 4 filler trials. 

At this stage, this is all I can think of to ask. Any help is gladly appreciated. Please forgive my idiocy.