Pausing and Resuming during a procedure

[Tony Zuccolotto]

Matt,

I would recommend trying something like setting your stimulus duration
to 0 and then running a Wait object immediately after the object.   The
Wait object will not alter the display when it runs but can collect an
input.   You should then probably write some script to examine the
Wait.RESP property to determine if the input that came in is your
pause/resume key.  If so, you can then run another Wait object, or
possibly use the goto command with a Label placed above the Wait object
to rerun the current object.   Note though that if you use Goto
statements and labels to jump execution around in the trial procedure
you should take care to make sure all the relevant attributes you need
to log to the data file are updated to current values (e.g. call
c.SetAttrib "name", "value" as needed to update attributes in the
context) and then call c.Log sometime prior to the goto.  The c.Log call
will cause a new row to be generated in the data file with all the
current attributes.   Normally you don't have to do this because a c.Log
call happens automatically at the end of the trial procedure, but if you
start jumping around then you typically must make some calls yourself to
assure all the data you are interested in gets logged.

Another approach to consider would be to use two different input masks
on the same stimulus presentation object.  For example you could create
a keyboard mask and set 1 and 2 as allowable response keys for the
stimulus, but then create another keyboard input mask on the same object
with P (for pause) as the only allowable key.   The first input mask can
be set to terminate, and the second one can be set to Jump to a specific
label.   You then put script after the label to do whatever special
processing is required to implement a pause/resume feature. 

Hope that gives you some ideas to try out.  You might need a few lines
of script to accomplish what you want, but you should definitely be able
to implement this in E-Prime.

Thanks,
Tony

*** DISCLAIMER: ALL VIEWS EXPRESSED ARE MY OWN AND DO NOT NECESSARILY
REFLECT THOSE OF PSYCHOLOGY SOFTWARE TOOLS ***

Anthony P. Zuccolotto
Vice President
Psychology Software Tools, Inc.
2050 Ardmore Boulevard
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Email     anthony.zuccolotto at pstnet.com
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> -----Original Message-----
> From: Matt Conroy [mailto:mconroy at ucsd.edu]
> Sent: Wednesday, October 08, 2003 4:43 PM
> To: eprime at mail.talkbank.org
> Subject: Pausing and Resuming during a procedure
> 
>   I am creating an experiment that requires subjects to orally
identify
> visual stimuli, which are presented sequentially.
>   I want to make a subject input that can pause the stimulus
presentation
> (during which the current stimulus remains on the screen indefinitely)
and
> a
> second input that causes the stimulus presentation to resume normally.
>   It is important to record the time of these inputs, or the stimulus
> during
> which they occurred.
> 
>   Thank you for any advice.
> 
> Matt Conroy
> Graduate Student
> UC San Diego Psychology Dept
> mconroy at ucsd.edu
> 
>