Hi all,
I have a set of picture stimuli, and I want to set correct responses for my trial. However, my correct responses are different within the picture element, i.e. m25, m30, m35, and m40 have correct response as lbuttondown, and m60, m65, m70, and m75 have correct response as rbuttondown. I know that I can create two picture elements and two separate trials so that I can distinguish the correct responses with the picture elements, but I was hoping that there might be an easier way where I can have just the one picture element and one foil trial.Thanks.
<picture foil>/ items = ("m_25.jpg", "m_30.jpg", "m_35.jpg", "m_40.jpg", "m_60.jpg", "m_65.jpg", "m_70.jpg", "m_75.jpg")/ select = noreplacenorepeat/ position = (50%,50%)</picture>
<trial foil_1>[....]/ stimulustimes = [0=forwardmask; 50=Word; 100=backwardmask; 150=foil;1000=blackrectangle]/ inputdevice = mousekey/ validresponse = (rbuttondown, lbuttondown)/ responsetime = 150/ response = timeout(3000)</trial>
You can do this by using the '/ iscorrectresponse' attribute in your <trial> element. Basically you need to set up another element, e.g. a <counter>, that holds the correct responses for your picture stims:
<counter correctresp>/ items = ("lbuttondown", "lbuttondown", "lbuttondown", "lbuttondown", "rbuttondown", "rbuttondown", "rbuttondown", "rbuttondown")/ select = current(foil)</counter>
and check if the response on the trial is equal to the one returned by the counter:
<trial foil_1>[....]/ stimulustimes = [0=forwardmask; 50=Word; 100=backwardmask; 150=foil;1000=blackrectangle]/ inputdevice = mousekey/ validresponse = (rbuttondown, lbuttondown)/ iscorrectresponse = [trial.foil_1.response==counter.correctresp.selectedvalue]/ responsetime = 150/ response = timeout(3000)</trial>
~Dave
"To understand recursion, you must first understand recursion." - Unknown Zen Master