Fwd: Do ... Loop

[Pedro Margalhos]

---------- Forwarded message ----------
From: Pedro Margalhos <marg...@gmail.com>
Date: 28/01/2008 16:18
Subject: Do ... Loop
To: e-p...@googlegroups.com

Hi,

 

I'm trying to set an experiment with e-prime to run a flicker paradigm. Therefore, i need do use a Do ... Loop Statement (more specifically a Do ... Loop Until condition). This because i need to have the stimulus repeated until the condition/answer is True.

The experiment consists in presenting a fixation cross, a picture (A), a mask, a picture (A'), a mask, and then have the participant to signal if there were any differences between both images presented. If there is no answer or a wrong (False) from the participant the set must be repeated.

 

Thanks in advance,

 

Pedro Margalhos Rodrigues

 

[ben robinson]

it sounds like all you may really need is an If... Then statement.

'this is what you'll need in your trial procedure time-line:
Label1
fixation
A
mask
A'
Inline1:
If A'.ACC = 0 Then Goto Label1
'this If... Then statement will cause the script to return to the beginning of the trial if the incorrect response is given (A'.RESP = 0)

[David McFarlane]

Pedro,

Or, try running your flicker procedure from an ordinary E-Prime
list. First set the list(let's call it FlickerList) to run some very
large number of times or seconds (essentially forever). In your list
procedure, have an Inline object with the following line:
If A'.ACC = 1 Then FickerList.Terminate

This will repeat the list until the subject gives a correct answer,
and the correct answer will terminate the list.

(For advanced users, the line could be
If (A'.ACC Or GetUserBreakState()) Then FickerList.Terminate
i.e., (1) The test A'.ACC <> 0 is implied, and (2)
GetUserBreakState() allows the developer to gracefully exit the list
using the <ctrl><shift> key combo.)

---
David McFarlane, Systems Designer
Dept. Psychology, Michigan State University
mcfa...@msu.edu www.msu.edu/~mcfarla9
Voice: (517) 353-0799 Fax: (517) 353-1652

At 1/28/2008 12:58 PM Monday, you wrote:
>it sounds like all you may really need is an If... Then statement.
>
>'this is what you'll need in your trial procedure time-line:
>Label1
>fixation
>A
>mask
>A'
>Inline1:
>If A'.ACC = 0 Then Goto Label1
>'this If... Then statement will cause the script to return to the
>beginning of the trial if the incorrect response is given (A'.RESP = 0)
>
>On Jan 28, 2008 11:31 AM, Pedro Margalhos

[Pedro Margalhos]

Hi once again,

 

First of all, thanks for the tips.

 

Secondly, i need other help:

I need to present the following (In a Flicker Paradigm):

 

Fixation cross (textdisplayobject)

StimulusA (slideObject)

Mask(textdisplayobject)

StimulusA'(slideObject)

Mask(textdisplayobject)

 

This set need to be presented until the subject gives an answer (i.e: until the subject gives an answer the images must be repeatedly presented).

 

when the subject gives an answer, the following happens:

1. If the subject answer 0 then the next pair of stimulus appear;
2. If the subject answer 1 then Goto a SlideObject to answer a different question;
3. This situation happens independently of the subjects answer.

Once again Thanks in advance,

 

Pedro Margalhos Rodrigues

 

p.s. I'm sorry for all the questions but I'm starting with E-Prime and Visual Basic it's not my speciality.

---------- Forwarded message ----------
From: Pedro Margalhos <marg...@gmail.com>
Date: 28/01/2008 16:18
Subject: Do ... Loop
To: e-p...@googlegroups.com