+x+xDear experts,
I am trying to modify the adaptive n-back task (from Jaeggi et al 2010).
In this task, stimuli are selected from a list of items. The version that I am programming includes three conditions:
1-back, where correct response is to press a button if the current stimulus is the same than the previous one
2-back, where correct response is to press a button if the current stimulus is the same than the stimulus presented two positions before
3-back, where correct response is to press a button if the current stimulus is the same than the stimulus presented three positions before
In the original script the stimuli selection is made using the "replace" option. However, I need a version with no lures. It means that, for example, if the participant is performing the 3-back condition, 1-back and 2-back conditions cannot appear.
I am not familiarized with Inquisit programming options, and I wonder if I could somehow specify the following conditions for stimulus selection:
//Assuming that N is the n-back condition
// Declare the following variables:
values.n1 = 0;
values.n2 = 0;
values.n3 = 0;
// Conditions for stimulus selection
if ( values.N = 1) {
do {
values.currenttarget = list.items.item(values.N);
} while (values.currenttarget = values.n2 or values.currenttarget.n3)
else if ( values.N = 2) {
do {
values.currenttarget = list.items.item(values.N);
} while (values.currenttarget = values.n1 or values.currenttarget.n2)
else if ( values.N = 3) {
do {
values.currenttarget = list.items.item(values.N);
} while (values.currenttarget = values.n1 or values.currenttarget.n2)
// Update the variables after each trial
values.n1 = currenttarget;
values.n2 = values.n1;
values.n3 = values.n3
I hope you understand this issue.
Thank you very much!
Best regards,
Naiara
You'll want the list set to selection with replacement, but use /not attributes to exclude the item numbers you do not want.
Concretely, the following changes to the code would be among those required:
<picture startshape>
/ items = shapes
/select = noreplace/size = (40%, 40%)
</picture>
// add variables to block selection of what would amount to a 1-back target during a 2-back block or 2-back block
// or what would amount to a 2-back target during a 3-back block
<values>
/ not1back = 0
/ not2back = 0
</values>
*list.notargetvalue selects any of the 8 numbers but the one selected for targetvalue
<list notargetvalue>
/items = (1, 2, 3, 4, 5, 6, 7, 8)
/ not = (values.currenttarget)
/ not = (values.not1back)
/ not = (values.not2back)/ selectionrate = always/ replace = true</list>
<trial nontarget>
/ ontrialbegin = [
trial.nontarget.insertstimulustime(clearscreen, parameters.stimulusPresentationtime);
if (values.N > 0){
values.currenttarget = list.items.item(values.N);
};
if (values.N == 1){
// no additonal constraints during 1-back;
// unclear whether you would consider what would amount to a 2-back target during a 1-back block a "lure"
values.not1back = 0;
values.not2back = 0;
} else if (values.N == 2) {
// block what would amount to a 1-back target during 2-back block;
// unclear whether you would consider what would amount to a 3-back target during a 2-back block a "lure"
values.not1back = list.items.item(values.N-1);
values.not2back = 0;
} else if (values.N == 3){
// block what would amount to either a 1-back or a 2-back target during a 3-back block;
values.not1back = list.items.item(values.N-1);
values.not2back = list.items.item(values.N-2);
} // the adaptive n-back has no maximum n-level, so you need to decide what to do if n gets greater than 3;
else if (values.N > 3) {
values.not1back = 0;
values.not2back = 0;
};]
/ stimulustimes = [0 = nontargetshape]
/validresponse = (noresponse, "A")
/ beginresponsetime = 0
/ correctresponse = (noresponse)
/ ontrialend = [
trial.nontarget.resetstimulusframes();
list.items.insertitem(picture.nontargetshape.currentitemnumber, 1);
list.blockACC.appenditem(trial.nontarget.correct);
//summary variables:
if (trial.nontarget.correct){
values.responseCategory = "CorrReject";
list.commissions.appenditem(0);
if (values.N == 0){
list.commissions_N0.appenditem(0);
} else if (values.N == 1){
list.commissions_N1.appenditem(0);
} else if (values.N == 2){
list.commissions_N2.appenditem(0);
} else if (values.N == 3){
list.commissions_N3.appenditem(0);
} else if (values.N == 4){
list.commissions_N4.appenditem(0);
} else if (values.N == 5){
list.commissions_N5.appenditem(0);
} else if (values.N == 6){
list.commissions_N6.appenditem(0);
};//if further values of N should be added, add the necessary code here
} else {
values.responseCategory = "Commission Error";
list.commissions.appenditem(1);
list.commissionsRT.appenditem(trial.nontarget.latency);
if (values.N == 0){
list.commissions_N0.appenditem(1);
list.commissionsRT_N0.appenditem(trial.nontarget.latency);
} else if (values.N == 1){
list.commissions_N1.appenditem(1);
list.commissionsRT_N1.appenditem(trial.nontarget.latency);
} else if (values.N == 2){
list.commissions_N2.appenditem(1);
list.commissionsRT_N2.appenditem(trial.nontarget.latency);
} else if (values.N == 3){
list.commissions_N3.appenditem(1);
list.commissionsRT_N3.appenditem(trial.nontarget.latency);
} else if (values.N == 4){
list.commissions_N4.appenditem(1);
list.commissionsRT_N4.appenditem(trial.nontarget.latency);
} else if (values.N == 5){
list.commissions_N5.appenditem(1);
list.commissionsRT_N5.appenditem(trial.nontarget.latency);
} else if (values.N == 6){
list.commissions_N6.appenditem(1);
list.commissionsRT_N6.appenditem(trial.nontarget.latency);
};//if further values of N should be added, add the necessary code here
};
]
/ trialduration = parameters.SOA
</trial>