WHAT REDUCES READING PERFORMANCE ON COMPU TER SCREENS - THE INFLUENCEOF RESTRAINED POSTURE ON WORK WITH VISUAL-DISPLAY UNITS

In two experiments the effects of orientation (horizontal versus verti cal and flexible handling of computer screens and paper on reading per formance were examined. In the first experiment, orientation of the me dium was varied in three conditions: a monitor in vertical orientation , and paper in vertical and horizontal orientation. The subjects had t o proofread texts over a period of 2.5 hours, and reading performance treading velocity and accuracy) was tested. The results show that read ing performance in computer screens is not as good as on paper. Howeve r, orientation of the medium cannot account for this finding, since on paper the vertical condition is better than the horizontal condition. In the second experiment it was tested whether flexible handling infl uences proofreading performance on computer screens. Two conditions we re examined: A traditional fixed computer screen and a condition in wh ich subjects were free to move the monitor. Additionally, body and mon itor positions were videotaped. There was no significant effect of fre e handling on proofreading performance. This could be due to the findi ng that only half of subjects moved the screen while reading.