Auditory and visual effects on solutions to computerized mathematics problems as a function of rate of digit...

This exploratory investigation concerned the effects of both auditory and visual stimulus variations on the accuracy of mental solutions to addition problems presented on a computer screen (CRT). 5 intensities of background noise and 5 background hues were presented randomly to 123 undergraduate volunteers as they mentally summed 25 numerals ranging from 1 to 5 at rates of either 1 sec. or 3 sec. per numeral timed from the onset of the previous numeral. A 2 x 2 x 5 mixed splitplot factorial analysis of variance gave a significant difference in errors between rates of digit presentation with greater accuracy associated with the 3-sec. rate. There was no significant difference in mean errors for auditory vs color modalities, yet a post hoc Newman-Keuls paired-comparison test of decibel levels at the 1-sec. rate of digit presentation gave a significant difference in mean errors between 60-dB and 70-dB sound-pressure levels (SPLs) of white masking noise. Also, a post hoc F test on differences between successive stages indicated significant differences suggesting a "learning set." Comparisons between 'everyday' instances of these noise levels are made with implications for optimal computational environments.