The effect of prolonged cathode ray tube (CRT) work on the afferent visual neural and focusing system of the human eye was examined by visually evoked potentials (VEPs) and laser optometer techniques, respectively. These measures were compared with parallel measurements of search performance. Ten volunteers performed three 4-hr sessions of a search/decision task on a high-resolution-red/ green/blue (RGB) monitor. Stimuli were numbers and symbols presented in a blue/black, red/black, or red/green foreground/background combination. Results showed minimal changes in the neural and focusing responses to each foreground/background combination over time on task. Weak correlations were found between neural-optical and search performance measurements. These data suggest that the use of chromatic stimuli in the color combinations examined do not have a detrimental effect on visual performancé.
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