Useful E-Prime Script

Title	Useful E-Prime Script
Version	5th June, 2023

A summery regarding E-Prime script.

Set random interval

In designing experiments, to avoid the influence of irrelevant variables caused by subject expectancy effects, it is necessary to randomize the presentation time of masked stimuli.

Method 1

Object.duration = Random (200,600) 

Method 2

Object.duration = 2 * Random (100,300) 

Have a rest during full session

To avoid the fatigue effect caused by long-term experiments, it is necessary to set rest intervals between trials.

Define E-Prime User Script

Dim N as Integer

Method 1

c.GetAttrib (“ListName.sample”) 
if N mod 40 = 0 Then 
    msgbox (“It’s time to rest ! “Press SPACE to continue”)
End If

Method 2

N=N+1
If N Mod 40 = 0 Then
	GoTo label1
Else
	GoTo label2
End If

Practice or real session

Choose between practice and formal testing, it can be automatic (based on accuracy) or manual (based on selection).

Method 1

If Object.RESP= 1 Then Goto Label1
Else
Goto Label2
End If

Method 2

Define E-Prime User Script

Public N as Integer

If Object.ACC=1 Then
    N = N+1
End If

If (N/PracticeList.Size)<0.80 Then 
    N=0
GoTo label3 
Else
GoTo label4
End If 

Open port

Method 1

Experiment properties - Devices add Parallel Port

Method 2

Object.OnsetSignalEnabled = True 
Object.OnsetSignalPort = &H0378
'Open Port
Object.OffsetSignalEnabled = True 
Object.OnsetSignalPort = &H0378
'Close Port

Stimulus marker

Parallel Port

WritePort &H0378, 0
Object.OnsetSignalData = c.GetAttrib ("Code")

Serial Port

Object.Tasks.Reset If 
    Serial.GetState() = ebStateOpen Then
Object.Tasks.Add Serial.CreateTask ("Object.OnsetTime", 0, "WriteByte", "(custom)", c.GetAttrib("Mark"), "Byte", True)
End If

If Serial.GetState() = ebStateOpen Then
    Object.Tasks.Add Serial.CreateTask ("Object.OnsetTime", 10, "WriteByte", "(custom)", ebDigit_0, "Byte", True)
End If

Socket Port

Object.Tasks.Reset

Object.Tasks.Add Socket.CreateTask("Object.OnsetTime", 0, "WriteByte", "(custom)", c.GetAttrib("Code"), "Byte", True)

Response marker

Parallel Port

If Object.Acc = 1 then 
    WritePort &H0378,77
Else If Object.Acc = 0 then 
        WritePort &H0378,88
else
        WritePort &H378,99
    End If
End If

Serial Port

Experiment properties - Devices add Parallel Port

Const sleeptime As Integer = 5

If target.acc=1 Then 
    Serial.WriteByte 77
Else Serial.WriteByte 88
End If 

Sleep(sleeptime)
Serial.WriteByte 0

Socket Port

Define E-Prime User Script

Const sleeptime As Integer = 5

If target.acc=1 Then 
    Socket.WriteByte 77
Else Socket.WriteByte 88
End If 

Sleep(sleeptime)
Socket.WriteByte 0

Others

Custom response in a TextDisplay Object

If Object.ACC = 1 Then

	Feedback.Text ="Correct!" 
	Feedback.ForeColor = Color("Blue")
    	Feedback.FontSize = 28

Else
	Feedback.Text ="Wrong!" 
	Feedback.ForeColor = Color("DarkRed")
    	Feedback.FontSize = 28

End If

For the color code pleae refer to https://shorturl.at/eiPS2 (PST support site) for reference.

E-Prime online resource

E-Prime Command Reference https://pstnet.com/ecr/

PST support service https://support.pstnet.com/hc/en-us

PST YouTube Channel https://www.youtube.com/@PSTNET

E-Prime Google Group https://groups.google.com/g/e-prime

[TBC]