Millisecond Forums

I've just tried to replicate the Valent/Neutral Categorisation Task (Werner & Rothermund, 2012) in Inquisit 3, and encounter con with the following troubles:
first, I used stimulustimes attribute to present the trial. I know the LCD refresh rate might have something to do with the accuracy of time, but it doesn't mean a lot to me. Well I run the Monkey and everything seems all right. Then I checked the data, and suddenly discovered that there's something wrong with the stimulusonsets. The trial should present in the sequence of fixation(500ms) - blank screen(200ms) - priming(150ms) - blank screen(50ms) - target(200ms) - interval(200ms). But what I found was:
stimulusonsets1 stimulusonsets2 stimulusonsets3 stimulusonsets4 stimulusonsets5
5 855 705 855 905
My script:
<text prime_PN>
/items =prime_PN
</text>
<text target_PN>
/items =target_PN
</text>
<text fixation>
/items=("+")
/fontstyle=("Arial",48px)
</text>
<text blank>
/items=("　　")
</text>
<trial PN_PN_L>
/validresponse=("D","K")
/correctresponse=("D")
/stimulustimes=[1=fixation;400=blank;700=prime_PN;850=blank;900=target_PN]
/posttrialpause=250
</trial>
Maybe anyone can tell me what's wrong with the second stimulus?

Second problem is about the blank screen or the mask according to what I actually put into use. If I set the text stimulus for the blank trial with no string, one of the priming text item will take the place. So I have to set the stimulus with several spacebars. It works, but I would prefer any better alternative if it is possible.

Third, and the most critial problem is, I couldn't set the assignment perfectly balanced as the original paper done.According to the paper, amount of positive and negative primes are both 20, and neutral primes are 40. The assignment of targets are the same. Each target will be paired with one positive, one negative and two neutral primes. That will make the total pairs(trials) upto 320. The valence relations and affective congruency will be perfectly balanced (valent prime - neutral target 25%,neutral prime - valent target 25%, valent prime - valent target 25%, neutral prime - neutral target 35%; of valent - valent trials, affective congruency and affective incongruency are both 50%)
Well I cut down the amount to half, so there will be 160 trials totally. And I tried different ways to put down my scripts but all failed in getting the balanced assignment. It's interesting that when I used 8 items (positive and negative primes and targets are all 2) to create a simple evaluative priming task, every target was presented two times while the selection of primes were always unequally. And I just switched the prime and target items, I still found the same result. I post my scripts down here, and beg anyone to help me find out what the problem really is.
Trials are all in the same form as I post above. And I've also tried to change the stimulustimes to stimulusframes, and the result is the same.
<block pr1>
/trials=[1-8=noreplace(PN_PN_Lp,NN_NN_Lp,PN_NN_Lp,NN_PN_Lp)]
</block>
And the following script is one block of the valent/neutral task. PN_NN means postive prime paired with negative target (n stands for noun, what I set for further design of experiments), the other trial names are in the same way, and UN means neutral. I set 5 affective congruency and 5 incongruency in one block in order to make the balance.
<block L1>
/trials=[1,9,17,25,33=noreplace(PN_PN_L,NN_NN_L);5,13,21,29,37=noreplace(PN_NN_L,NN_PN_L);2,6,10,14,18,22,26,30,34,38=UN_UN_L;4,8,12,16,20,24,28,32,36,40=noreplace(UN_PN_L,UN_NN_L);3,7,11,15,19,23,27,31,35,39=noreplace(PN_UN_L,NN_UN_L)]
</block>

Thank you a lot for reading my poor description.