Re: reaction time measures

[Pawel Kusmierek <pawel.kusmierek@xxxxxxxxx>]

I know that people are happy with Presentation http://www.neurobs.com/
.  I am not sure how well it does handle timing of visual stimuli,
though you will probably have some idea if you read through their
online documentation. It maybe also informative in general way.

Keep in mind that timing of responses in one thing. The other thing is
timing of stimulus delivery - for visual stimuli you basically have to
be able to know when the frame display occurred.  With typical refresh
rate of 60 Hz you will get an error of up to 16 ms, if you don't look
into this. For this reason, I know people who decided to use LEDs
rather than fiddle with the display frames. Which is of course only
possible if you are happy with _very_ simple stimuli.

Similarly, if your program plays a sound under windows, the playback
latency will be around 20 ms unless you know how to bypass or
circumvent standard windows sound engine.

Nevertheless, it is possible to get ~1ms accuracy under windows, as
shown here http://www.neurobs.com/presentation/docs (go to
Timing>Uncertainties) and here
http://kusmierek.republika.pl/fiodor.html (see Timing capabilities
example ).

Good luck,

Pawel



--
Pawel Kusmierek PhD
Department of Physiology and Biophysics
Georgetown University Medical Center
The Research Building WP23
3970 Reservoir Road NW
Washington, DC 20007
phone: +1 202 687-8851 or 8028