Have fixation shown for duration if a key is pressed

[liwenna]

obviously...

"if triallist.sample > 1 then
fixationslide.duration = 500 + (2500 - prevrt)fixationslide.duration =
500 +(2500 - prevrt)"

... should be:
"if triallist.sample > 1 then
fixationslide.duration = 500 + (2500 - prevrt)"

On Nov 5, 10:21 pm, liwenna <liwe... at gmail.com> wrote:
> Hey Cishores,
>
> Am I correct to think that you basically want/need to ensure that
> there is exactly 2,5 seconds + the 'normal fixation time' between the
> onset of the image and the next cue?
>
> How about prolonging the duration of the fixation cross on the NEXT
> trial with the remainder of the 2.5 seconds?  This way you also won't
> end your last trial with a fixationcross as you would if an extra
> fixationcross is added at the end of a trial.
>
> I am not entirely sure if my suggestion works (or works right away) as
> I have no e-prime to try at the moment... but what you could do is:
> first declare a global variable that will have the response time for
> each trial written to it so it can be used in the next trial: on the
> user tab of the script window type "declare prevRT as integer".
> On your trialproc  you probably have 3 slides: fixationslide, cueslide
> and imageslide (i am just making up some names now). Insert an inline
> after the imageslide that writes the response time to the 'prevRT'-
> variable: if imageslide.rt > 0 then prevRT = imageslide.rt (the first>0 part is to ensure that there actually WAS a response during the
>
> imageslide, I don't know what you want the program to do in case of no
> response... things might actually be done litle different depending on
> that). Now at the end of the trial the variable prevRT holds the
> response time on that trial and carries this value over to the next
> trial, so we can use it to prolonge the fixationslide. I think that
> that should be possible by placing an inline right before the
> fixationslide with something like: "if triallist.sample > 1 then
> fixationslide.duration = 500 + (2500 - prevrt)fixationslide.duration =
> 500 +(2500 - prevrt)" wherein 500 is my guess at your 'normal'
> fixationslide duration, the (2500 - prevrt) is rather obvious I hope
> and the if triallist.sample > 1 part should ensure that the first
> trial doesn't start with a 3000 ms fixation cross.
>
> I think that in order for this to work you should leave the duration
> on the fixationslide properties tab empty.
>
> I hope that this is of some help to you. As said: no e-prime here, so
> no trying out and no guarantees :) Alternatively it might be possible
> to use two states on your imageslide, one with the image and one is an
> 'extra' fixationcross and then have the 2500 ms slide switch states
> when a response is given, but a) not sure if that works, b) can't make
> up the code top of my head and c) code would depend on the inputdevice
> for the response I think.
>
> Best regards,
>
> liwenna
>
> On Nov 5, 7:38 pm, David McFarlane <mcfar... at msu.edu> wrote:
>
> > Then I did not follow the description of your experiment, sorry.
>
> > -- David McFarlane, Professional Faultfinder
>
> > >That makes the image stay on the screen for the duration.  We want the
> > >fixation image to display for the remainder of the time.
>
> > >THanks for the reply.
>
> > >On Nov 5, 12:23 pm, David McFarlane <mcfar... at msu.edu> wrote:
> > > > Try setting End Action to (none).
>
> > > > (I just did my own search of the Getting Started and User's Guides,
> > > > you only learn this in passing deep within Chapter 3 of the User's
> > > > Guide.  I don't even remember how I learned this myself, probably
> > > > just pressing all the buttons myself long ago as I continue to do to
> > > > this day.  This really needs to be better documented.  But I would be
> > > > glad to be corrected.)
>
> > > > -- David McFarlane, Professional Faultfinder
>
> > > > >We currently have an experiment when the subject is shown a fixation -
> > > > >a cue - an image.  They are given 2.5s to respond to the image.  If
> > > > >they respond before the 2.5s is up we would like the fixation to
> > > > >display for the remainder of the 2.5s.
>
> > > > >Is there an easy way to do this?
>
> > > > >Thanks!
--~--~---------~--~----~------------~-------~--~----~
You received this message because you are subscribed to the Google Groups "E-Prime" group.
To post to this group, send email to e-prime at googlegroups.com
To unsubscribe from this group, send email to e-prime+unsubscribe at googlegroups.com
For more options, visit this group at http://groups.google.com/group/e-prime?hl=en
-~----------~----~----~----~------~----~------~--~---