<ep> <fd 1><d 59> <s 1><cr><t 1500><id keyboard> <dbc 210210210>

<dfs 36><vm 1024,768,768,16,60><nfb><rcot><eop>

$

! Counting Stroop task;

! Includes one counting block;

! 9 trials per block, scrambled within block;

 

! Item number AB;

! A=condition (1=congruent, 2=neutral, 3=incongruent);

! B= item number in condition;

! last edited on 11-21-05;

 

0 <d 10>"Press SPACEBAR to start";

0 <d 10><ln -1> "Press key to indicate the number of objects", <ln 1> "Ignore the actual object" <ms% 7000>/c;

0 <d 10><% 59> /c;

$

+11 * <umnr>1<umpr>2<mpr +14>3<mnr +2>5<mnr +3> "1" <% 30> /<% 60>/;6

+12 * <umnr><umpr><mpr +2><mnr +1><mnr +3> "2           2" <% 30> /<% 60>/;

+13 * <umnr><umpr><mpr +3><mnr +1><mnr +2> "3           3          3" <% 60> /<% 60>/;

+21 * <umnr><umpr><mpr +1><mnr +2><mnr +3> "X" <% 30> /<% 60>/;

+22 * <umnr><umpr><mpr +2><mnr +1><mnr +3> "X           X" <% 30> /<% 60>/;

+23 * <umnr><umpr><mpr +3><mnr +1><mnr +2> "X           X         X" <% 30> /<% 60>/;

+31 * <umnr><umpr><mpr +1><mnr +2><mnr +3> "3" <% 30> /<% 60>/;

+32 * <umnr><umpr><mpr +2><mnr +1><mnr +3> "1           1" <% 30> /<% 60>/;

+33 * <umnr><umpr><mpr +3><mnr +1><mnr +2> "2           2          2" <% 30> /<% 60>/;

$

0 <d 10><ln -1> "Experiment Complete!", <ln 1> "Thank you for participating.";
$

 

1: UMNR/Unmap Negative Response – This command unmaps all buttons that have been previously mapped to the negative response (e.g., the key which, when pressed, indicates a negative response).  By default, the left shift key is mapped to the “negative response”; thus, at this point in the script, <umnr> unmaps the left shift key.

2: UMPR/Unmap Positive Response – This command unmaps all buttons that have been previously mapped to the positive response.  {by default the right shift key is mapped to the + response).

3: MPR/Map Positive Response – This command tells DMDX to associate the indicated key with the positive response.  You can have as many positive responses as you like.  However, one key cannot be mapped to both positive and negative response (obviously).  In this example, the 1 key will now indicate a positive response (when the 1 key is pressed, DMDX will see that as a positive response).

4: When a “plus sign” symbol is placed within the mapping response keywords it indicates the depression of the key.  In this example, +1 stands for the depression of the 1 key.  Thus, DMDX will record the time at which the 1 key is depressed (as opposed to the time at which the 1 key is released, which would be indicated with a  – sign before the 1).  Do not confuse this + with the + at the beginning of the line (as a correct response indicator) which would indicate that the positive response is the correct response for the trial.

5: MNR/ Map Negative Response – This command tells DMDX to associate the indicated key with the positive response.  In this example, the depression of the 2 or the 3 key will be seen as a negative response.

6:  Collectively, the mapping and upmapping keywords and the + correct response indicator at the start of the item function such that if the participant presses the one key, it will be recorded as correct and the 2 or 3 key will be recorded as incorrect.  If the participant presses any other key, DMDX will not register that a response has been made. 

Note:  This file is in AZK format.  The AZK file imposes 2 limitations on the type of output one can gather. 

First, AZK files will only accept one response per trial.  In contrast, ZIL can allow multiple responses per trial/item.  In this example, this is not a problem because we only want one response for each item. 

Second, AZK output will only indicate if the response was correct or incorrect, not the actual response that was selected.  In this example this limitation causes a problem.  Because there are two possible negative responses, we can know if the participant provides an incorrect response, but we will not know WHICH incorrect response was provided.  ZIL format (used with ZOR, which forces ZIL to accept only one response per trial) will overcome this limitation.  See the ZOR version of this script to see how. 

 

Created by Becky McGill

Last edited 11-21-2005