Interaction of Illumination with noise on neuropsychological performance capability

To determine the interaction effect of illumination with noise performance data were recorded from 20 male college student volunteers on a battery of neuropsychological tests comprising 'memory and search,' 'name and number checking,' 'Flanagan's eye-hand coordination' and 'digit symbol.' Each subject worked under two of the four combinations of illumination (low, 300 lux; high, 500 lux) with quiet (60 dBA) and noise (100 dBA) conditions. A 2 x 2 analysis of variance was performed on the test scores. The accuracy of performance was found enhanced by high illumination in all the tests, but the speed of performance was impaired by noise. The interaction effect was significant, indicating the speed and efficiency of performance increasing while the accuracy of performance affected differently with high illumination under noise condition. However, the error of performance increased by noise under high illumination. Further investigation on a range of neuropsychological tests is suggested before the conclusions are drawn more firmly.