All,
Holmqvist et al (2011), Ch. 13, p.428 suggests that, "using a stimulus monitor with, for instance, an 8 ms refresh time will reduce the efficient speed to 125 Hz for these measures, even if a much faster eye-tracker is being used." (Where "these measures" refers to a shopping basket of latency and distance measures.)
We have upgraded our lab to SMI 500's and are doing more and more gaze contingent things as well as tracking fixations (and other measures) on dynamic displays as, e.g., for video games (Tetris, Snake, Space Fortress, and more). In addition, after having used 60 Hz machines for the last 15 years, we are looking forward to doing more of the sorts of studies and measures that faster machines will support.
It is hard for us to assess the seriousness or limitation of the statement in Holmqvist. Note that we are well aware of the arguments made by Ulirch & Giray (1989) for sampling rates of computer and it seems certain that the same logic applies to monitors:
Ulirch, R. & Giray, M. (1989). Time Resolution of Clocks - Effects on Reaction-Time Measurement - Good News for Bad Clocks. British Journal of Mathematical \& Statistical Psychology, 42, 1--12.
On the other hand, it does seem like the disparity between 500 vs 125 hz between eye tracker and monitor would negatively affect the effective sampling rate.
We have an important, but secondary reason to consider LEDs; namely, their lower power draw and the lower heat they would output. This is important because, the acoustic pods where we run our Ss tend to get warm/hot with the doors closed. (Switching from two 60 watt incandescent light bulbs to two 10 watt LED bulbs has made a world of difference.)
So - although I don't see the "heat" issue sufficient to go out and buy new monitors, less heat and more accuracy would push me over the threshold.
Comments, advise, anecdotes would all be welcomed.
Many thanks,
Wayne
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