shows a rare example of changes in the instantaneous HR, systolic BP,
HRV index, and R-P latency. With the start of the successive task execution, the
R-P latency tended to shorten, and the HRV index tended to increase.
Conversely, the systolic BP tended to increase, and the instantaneous HR tended
to remain stable, possibly because the sympathetic nervous system's activity was
partially suppressed by the excessive mental strain. This is a case, in which the
physiological measures and evaluations vary asynchronously with each other.
This kind of asynchronous behaviour can cause the instantaneous HR (Fig. 6
vary dissimilarly, in comparison with the systolic BP, R-P latency, and HRV
The study examined the effects of gaze angle on ANS activity during seated
VDT operations. A non-statistically significant trend was found towards both
reduced error rate and perceived mental workload with a low gaze angle. The
effect on B-P and instantaneous HR were complicated by the interaction
between the gaze angle and the task difficulty and difficult to interpret. The
results showed the importance of observing several physiological measures to
evaluate its activity.
| Suzuki, K. &
Hayashi, Y. ( 1993). On a simple and effective method to analyze
heart rate variability. In Smith, M. &
Salvendy, G. (Eds.): Human Computer
Interactions: Applications and Case Studies (Vol. 1), Proc. 5th Int. Conference
on Human-Computer Interaction (HCI International '93, Orlando, USA, August 8-13, 1993), pp. 914-919. Amsterdam: Elsevier.|
| Nagasgima, K.,
Aiba, T.et al. ( 1994). Experimental study on an
evaluation of autonomic function using digital plethysmography. Bulletin of
Tokai University, School of High Technology for Human Welfare, 4, 215-221.
| Haga, S. ( 1994). The Japanese version of NASA task load index. RTRI Report, 8(1), 15-20. (in Japanese)|