Millisecond Forums

+x

 

PieterGoos - 1/10/2023

Hello,

I want to present a stimulus 5 times in a row through a parallel port (electrical stimulus through a Digitimer). It needs to be a 50 hz signal and needs to be presented in a trial.

I have tried to do this like this below, but it didn’t work (only presents the electrical stimulus once):

<port US>
/port = LPT1
/subport = data
/items = (“00000001”)

<trial US_50Hz>
/ stimulustimes = [0 = US; 20 = US; 40 = US; 60 = US; 80 = US; 2000 = cover]
/ timeout = 2000
</trial>

When for example using a sound as a stimulus, it will present the stimulus 5x in a row in a trial. How come this doesn't work?

Though, it works when I put the signal in a block (but this is no solution, because it needs to be presented in a trial together with a picture):

<trial US>
/ stimulustimes = [0 = US; 20 = cover]
/ timeout = 20
</trial>

<block US_50hz>
/trials = [1 = trial.US; 2 = trial.US; 3 = trial.US; 4 = trial.US; 5 = trial.US]
</block>

Does anybody know how to do this?

+x

 

Dave - 1/10/2023

+x

 

PieterGoos - 1/10/2023

Hello,

I want to present a stimulus 5 times in a row through a parallel port (electrical stimulus through a Digitimer). It needs to be a 50 hz signal and needs to be presented in a trial.

I have tried to do this like this below, but it didn’t work (only presents the electrical stimulus once):

<port US>
/port = LPT1
/subport = data
/items = (“00000001”)

<trial US_50Hz>
/ stimulustimes = [0 = US; 20 = US; 40 = US; 60 = US; 80 = US; 2000 = cover]
/ timeout = 2000
</trial>

When for example using a sound as a stimulus, it will present the stimulus 5x in a row in a trial. How come this doesn't work?

Though, it works when I put the signal in a block (but this is no solution, because it needs to be presented in a trial together with a picture):

<trial US>
/ stimulustimes = [0 = US; 20 = cover]
/ timeout = 20
</trial>

<block US_50hz>
/trials = [1 = trial.US; 2 = trial.US; 3 = trial.US; 4 = trial.US; 5 = trial.US]
</block>

Does anybody know how to do this?

<port US>
/port = LPT1
/subport = data
/items = ("00000001")
</port>

<trial US_50Hz>
/ stimulustimes = [0 = US; 20 = US; 40 = US; 60 = US; 80 = US; 2000 = cover]
/ timeout = 2000
</trial>

The port signal remains raised throughout the trial, just like a visual stimulus will remain on-screen for the duration of the trial.

You need to lower the signal in-between if you want to raise it repeatedly, i.e.

<port US>
/port = LPT1
/subport = data
/items = ("00000001")
</port>

<port allbitstolow>
/port = LPT1
/subport = data
/items = ("00000000")
</port>

<trial US_50Hz>
/ stimulustimes = [0 = US; 10=allbitstolow; 20 = US; 30=allbitstolow; 40 = US; 50=allbitstolow; 60 = US; 70=allbitstolow; 80 = US; 90=allbitstolow; 2000 = cover]
/ timeout = 2000
</trial>