This fast flicker is largely fused by our visual system ( Kristofferson, 1967 Andrews et al., 1996 Carmel et al., 2006), but not necessarily completely, as it can affect electrophysiological recordings ( Wollman and Palmer, 1995 Krolak-Salmon et al., 2003 Williams et al., 2004). In CRT monitors each pixel of the screen changes from bright to dark with certain vertical refresh rate frequency (60 Hz or higher), producing constant flicker. First, the light is not presented continuously, but discretely in flashes. Nevertheless, CRT monitors are not perfect as they continue to pose several limitations for researchers. These systems allowed researchers to adjust a much larger number of stimulus’ parameters and are partly responsible for the expansion of the research in vision. Later, these expensive devices were replaced by cheaper and broadly available cathode-ray tube (CRT) monitors, which could be controlled conveniently and flexibly via personal computers (PCs Brainard, 1989). In early times, accurate timing of visual stimuli was achieved by specialized apparatus such as tachistoscopes ( Mollon and Polden, 1978). The LCD monitor seems suitable for many applications in vision research, including the studies that require combined accuracy of timing and intensity of visual stimulation.Īccurate stimulus presentation is vital to research in vision, and the biggest limitations are imposed by the device used to display stimuli ( Krantz, 2000 Bukhari and Kurylo, 2008). Brightness was also delivered reliably across repeated presentations (<0.04% error) and across blocks with different durations (<3% error). The onset time was stable across repetitions, 95% confidence interval (the error) of which was <0.01 ms. Here we report that there is at least one new inexpensive 120 Hz model, whose timing and stability is on a par with a benchmark cathode-ray tube monitor, or even better. Despite their main advantages of continuous illumination and low electromagnetic emission, these monitors had problems with timing and reliability. Until now, liquid crystal display (LCD) monitors have not been used widely for research in vision.
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