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Domande generiche per collegare l'esperimento Inquisit con l'EEG

https://forums.millisecond.com/Topic36831.aspx

By Antonella - 1/21/2025

Good morning,
I will start with some general questions as I have no training in this and see if I can understand anything.

As with other example experiments, I now have to link my experiment in Inquisit to a /port = LPT ()

I have to define the markers which if I understand are associated with the stimuli.
I have 24 visual stimuli of the same duration, 24 auditory stimuli of variable duration and 24 visual+auditory stimuli of variable duration.

The markers are numeric codes.
1. Are these numeric codes generated by software or do we write them manually?
2. Do I only have to define 48 markers and then the machine will take these to mark the visual+auditory stimuli?
3. What is a trigger?

Basically in the code I am looking at I have this information which I would like to understand the meaning of:

<data>
values.startMarkerID, values.startMarker, values.faceMarker,......
</data>.

<trial debugTrial>
/ ontrialbegin = [
    expressions.initTrialVariables;
]
/ stimulustimes=[
    0=debugValues;
]
/ validresponse = (" ")
/ beginresponsetime = 0
/ recorddata = false
/ responseinterrupt = immediate
</trial>


<trial fixation>
/ stimulustimes = [0 = fixation, trial_start_marker, pulse_trigger;
       100 = fixation, reset_pulse, reset_marker;]
/ trialduration = (values.durationFixation)
/ showmousecursor = false
/ recorddata = false
/ branch = [trial.stim]
</trial>

<trial stim>
/ stimulustimes = [0 = picStim, pic_marker, pulse_trigger;
       100 = picStim, reset_pulse, reset_marker;]
/ trialduration = (5000)
/ showmousecursor = false
/ recorddata = false
/ branch = [trial.stim_offset]
</trial>

<trial stim_offset>
/ stimulustimes = [0=blank, trial_end_marker, pulse_trigger;
                 100=blank, reset_pulse, reset_marker;]
/ trialduration = (500) //give extra time to make sure that trigger is reset
/ showmousecursor = false
/ recorddata = false
/ branch = [
    if(values.trialType=="humanness"){
        slidertrial.MH_resp    
    }else if(values.trialType=="likability"){
        slidertrial.lik_resp
    }else if(values.trialType=="viewing"){
         trial.end_viewing_trial
    }
]
</trial>



Thank you to those who will answer me to start asking more precise questions
By Dave - 1/21/2025

Antonella - 1/21/2025
Good morning,
I will start with some general questions as I have no training in this and see if I can understand anything.

As with other example experiments, I now have to link my experiment in Inquisit to a /port = LPT ()

I have to define the markers which if I understand are associated with the stimuli.
I have 24 visual stimuli of the same duration, 24 auditory stimuli of variable duration and 24 visual+auditory stimuli of variable duration.

The markers are numeric codes.
1. Are these numeric codes generated by software or do we write them manually?
2. Do I only have to define 48 markers and then the machine will take these to mark the visual+auditory stimuli?
3. What is a trigger?

Basically in the code I am looking at I have this information which I would like to understand the meaning of:

<data>
values.startMarkerID, values.startMarker, values.faceMarker,......
</data>.

<trial debugTrial>
/ ontrialbegin = [
    expressions.initTrialVariables;
]
/ stimulustimes=[
    0=debugValues;
]
/ validresponse = (" ")
/ beginresponsetime = 0
/ recorddata = false
/ responseinterrupt = immediate
</trial>


<trial fixation>
/ stimulustimes = [0 = fixation, trial_start_marker, pulse_trigger;
       100 = fixation, reset_pulse, reset_marker;]
/ trialduration = (values.durationFixation)
/ showmousecursor = false
/ recorddata = false
/ branch = [trial.stim]
</trial>

<trial stim>
/ stimulustimes = [0 = picStim, pic_marker, pulse_trigger;
       100 = picStim, reset_pulse, reset_marker;]
/ trialduration = (5000)
/ showmousecursor = false
/ recorddata = false
/ branch = [trial.stim_offset]
</trial>

<trial stim_offset>
/ stimulustimes = [0=blank, trial_end_marker, pulse_trigger;
                 100=blank, reset_pulse, reset_marker;]
/ trialduration = (500) //give extra time to make sure that trigger is reset
/ showmousecursor = false
/ recorddata = false
/ branch = [
    if(values.trialType=="humanness"){
        slidertrial.MH_resp    
    }else if(values.trialType=="likability"){
        slidertrial.lik_resp
    }else if(values.trialType=="viewing"){
         trial.end_viewing_trial
    }
]
</trial>



Thank you to those who will answer me to start asking more precise questions

A <port> is a stimulus element like any other -- it works exactly like <text>, <picture>, or <sound>. A <port> stimulus is not "displayed" on.screen or played over your speakers, instead it is sent over the LPT port to any receiving equipment (e.g. an EEG machine). Its items are 8-bit TTL values, which you can either speciy as binary strings ("000000" to "11111111") or integer values 0 t0 255.