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Yes. For a go/nogo paradigm, you'll want to set up a bunch of <values> and <expressions> to track the metrics of interest (number of responses, number of correct responses, mean latency for trials where a response occurred). You can then report those statistics back to the participant via a <page> or <trial> element. Basic example:
<values> / sumlatency = 0 / nresponses = 0 / ncorrect = 0 / ntrials = 0 </values>
<expressions> / meanlat = (values.sumlatency/values.nresponses) / pctcorrect = (values.ncorrect/values.ntrials)*100 </expressions>
<expt> / postinstructions = (performance) / blocks = [1=myblock] </expt>
<block myblock> / trials = [1-12 = noreplace(go, nogo, nogo)] </block>
<trial go> / ontrialend = [if (trial.go.response != 0) {values.sumlatency += trial.go.latency; values.nresponses += 1;};] / ontrialend = [values.ncorrect += trial.go.correct] / ontrialend = [values.ntrials += 1] / stimulusframes = [1=gotxt] / validresponse = (57, 0) / correctresponse = (57) / timeout = 2000 </trial>
<trial nogo> / ontrialend = [if (trial.nogo.response != 0) {values.sumlatency += trial.go.latency; values.nresponses += 1;};] / ontrialend = [values.ncorrect += trial.nogo.correct] / ontrialend = [values.ntrials += 1] / stimulusframes = [1=nogotxt] / validresponse = (57, 0) / correctresponse = (0) / timeout = 2000 </trial>
<text gotxt> / items = ("RESPOND!") / txcolor = green </text>
<text nogotxt> / items = ("Do NOT respond.") / txcolor = red </text>
<page performance> ^Your mean RT was <%expressions.meanlat%> ms. ^You responded correctly in <%expressions.pctcorrect%> % of all trials. </page>
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