Millisecond Forums

Hi,

I'm really new to Inquisit and trying to create a pretty standard memory experiment that requires to show a structured sequence of images. I didn't see any previous post about this question, so any suggestion is greatly appreciated!

I'm trying to create a number of triplet images (meaning there's a set order between these three images and they will show up one by one in that order). But the order among the triplets should be randomized. No image should be the same. Let's say I try to create 3 triplets, each repeated 3 times within a block for 3 blocks. And across blocks, the order of the triplets should not be the same. For all of the images some of them are neutral picture, and others are negative. For those three triplets, one triplet has the structure of "negative, neutral, neutral", one "neutral, neutral, negative", and one "neutral, neutral, neutral". It does not matter which exact neutral or negative image it selects from the pool, because we want some randomization among subjects. In a word, each picture as two property: 1) negative or neutral 2) it's position in the triplet.

I hope I made it clear what I'm trying to get! I made a few attempts but it's not getting me very far to what i want to achieve. My idea is :
1) have two lists that have all the negative/neutral image paths. e.g.,
<list negativeImages>
/ items = ("./stimuli/negative/2053.jpg","./stimuli/negative/2141.jpg","./stimuli/negative/2205.jpg","./stimuli/negative/2301.jpg","./stimuli/negative/2345.1.jpg","./stimuli/negative/2352.2.jpg","./stimuli/negative/2307.jpg","./stimuli/negative/2399.jpg","./stimuli/negative/2413.jpg")
/ selectionmode = noreplace
</list>
(same for <list neutralImages>)

2)create three item variables that select from the negative and neutral image lists to determine what's which image is placed as the first one of the triplet or second or third. e.g.,
/1: first element of "negative, neutral, neutral" triplet
/2: first element of "neutral, neutral, negative" triplet
/3: first element of "neutral, neutral, neutral" triplet
<item 1stImages>
/1 = list.negativeImages
/2: = list.neutralImages
/3: = list.neutralImages
</item>
(Similar for <item 2ndImages> and <item 3rdImages>. Together item.1stImages.1 + item.2ndImages.1 + item.3rdImges.1 form the first triplet with structure "negative, neutral, neutral")

<picture 1stImages>
/items = 1stImages
/select = noreplace
</picture>

<picture 2ndImages>
/items = 2ndImages
/select = picture.1stImages.currentindex
</picture>

<picture 3rdImages>
/items =3rdImages
/select = picture.2ndImages.currentindex
</picture>

Question1: I don't quite how to let each item selects from the list. The console kept giving me errors. I think it was expecting a string-type of input (the image path) instead of reading from a list

Question2: It's possible to get duplicated stimuli from the same category under 1stImages, 2ndImages, and 3rdImages, since they're under different item elements and selected from the same list. How can I solve that?

3)display the triplet in random order for 3 times in each block. e.g.,

<trial encoding>
/ stimulustimes = [500 =1stImages; 2500=2ndImages; 4500=3rdImages]
/ correctresponse = ("j", "k")
/ validresponse = ("j", "k")
/ beginresponsetime = 0
</trial>

<block encoding>
/ preinstructions = (encodingIntro)
/ trials = [1-27 = encoding]
/ bgstim = (fixation)
</block>

Question3: this snippet of code doesn't really do what I expect.It seems like there's no set order within the triplet: each image will be selected from the pool of negative/neutral each time. How can I achieve this part?

Question4: How should I display the same triplet for multiple times? How do I randomize triplet order?

Sorry about these many questions all at once. Hope I made everything clear. I'd appreciate any help I can get!