angles while seated
Kaoru Suzukia and Dennis R. Ankrumb
a College of Engineering, Hosei University, 3-7-2 Kajinocho, Kogani-city,
Tokyo 184-8584 Japan
b Human Factors Research, Nova Solutions, 10007 San Luis Trail, Austin TX
The autonomic nervous system (ANS) regulates most bodily functions. While it has been established that ANS activity is affected by both physical and mental activities, the reverse might also be true.
For seated VDT operators, the lower gaze angle has several advantages. The advantages might not be limited to physical ones, such as reduced convergence effort and a reduced risk of dry eye syndrome. For example, the activity of the sympathetic and parasympathetic nervous systems, components of the ANS, are related to mental strain. If a lower gaze angle stabilizes its activity, that might have a desirable effect.
An experiment was conducted on seated subjects performing a VDT task. Both monitor placement and task difficulty were varied to compare ANS activity between gaze angles and task difficulty, and to examine interactions between gaze angle and task difficulty.
ANS activity can be estimated from several physiological measures. In many cases, the measures and evaluations calculated from them vary synchronously. However, in some cases, they vary asynchronously. Hence, to evaluate ANS activity, it is important to observe multiple physiological measures.