Stop Signal Task- Is the pracblock included in SSRT estimation?

Dave - 5/15/2023

+x

SanWin - 5/15/2023
I wonder if the Pracbloc is included in the global SSRT estimation, because I want to create an additional Pracblock without a stop signal, as shown below. Is it possible to do it this way, or could this skew my data?
Thank you very much.

   Practice 1 (1 Block of 16 Trials)
***********************************************************************************************************************************************************************
<block pracblock1>
/ onblockbegin = [values.trialnumber=0; values.blocknumber="Übung1"; values.countdown=values.waitbetweenblocks]
/ onblockend = [values.blocknumber=0; values.ssd=0; values.ssd_sum=0; values.ns_rtcorrsum=0; values.sr_rtsum=0;
    values.sr_ntotal=0; values.ns_nmiss=0; values.ns_ncorr=0; values.ns_ntotal=0; values.ss_ncorr=0; values.ss_ntotal=0;
    values.raw_rtsum=0; values.ns_nnoresp=0; values.ns_rtsum=0; values.ns_nresp=0]
/ onblockend = [if(values.resetpracticessd==true)values.ssd_next=values.ssd_start]
/ trials = [1=InstruktionTest; 2= Instruktion1; 3=Training; 4-19=noreplace(nstrial)]
/ recorddata = true
</block>

***********************************************************************************************************************************************************************
    Practice 2 (1 Block of 16 Trials)
***********************************************************************************************************************************************************************
<block pracblock2>
/ onblockbegin = [values.trialnumber=0; values.blocknumber="Übung2"; values.countdown=values.waitbetweenblocks]
/ onblockend = [values.blocknumber=0; values.ssd=0; values.ssd_sum=0; values.ns_rtcorrsum=0; values.sr_rtsum=0;
    values.sr_ntotal=0; values.ns_nmiss=0; values.ns_ncorr=0; values.ns_ntotal=0; values.ss_ncorr=0; values.ss_ntotal=0;
    values.raw_rtsum=0; values.ns_nnoresp=0; values.ns_rtsum=0; values.ns_nresp=0]
/ onblockend = [if(values.resetpracticessd==true)values.ssd_next=values.ssd_start]
/ trials = [1=Training2; 2-17=noreplace(nstrial,nstrial,nstrial,sstrial); 18= blocksummary; 19=Instruktion2]
/ recorddata = true
</block>

> I wonder if the Pracbloc is included in the global SSRT estimation.

No, practice trials are not included. There is an asterisk, however. In the original Verbruggen et al. implementation, SSD is not reset to its starting value after practice, i.e. the test block proceeds starting from whatever the SSD was at the end of practice. If you don't want this, the script explicitly contains a switch to reset the SSD after practice, and this is explained in the user manual.