The effect of concentric constriction of the visual field to 10 and 15 degrees on simulated motor vehicle accidents.

PURPOSE: Traffic accidents are associated with the visual function of drivers, as well as many other factors. Driving simulator systems have the advantage of controlling for traffic- and automobile-related conditions, and using pinhole glasses can control the degree of concentric concentration of the visual field. We evaluated the effect of concentric constriction of the visual field on automobile driving, using driving simulator tests. METHODS: Subjects meeting criteria for normal eyesight were included in the study. Pinhole glasses with variable aperture sizes were adjusted to mimic the conditions of concentric visual field constrictions of 10° and 15°, using a CLOCK CHART®. The test contained 8 scenarios (2 oncoming right-turning cars and 6 jump-out events from the side). RESULTS: Eighty-eight subjects were included in the study; 37 (mean age = 52.9±15.8 years) subjects were assigned to the 15° group, and 51 (mean = 48.6±15.5 years) were assigned to the 10° group. For all 8 scenarios, the number of accidents was significantly higher among pinhole wearing subjects. The average number of all types of accidents per person was significantly higher in the pinhole 10° group (4.59±1.81) than the pinhole 15° group (3.68±1.49) (P = 0.032). The number of accidents associated with jump-out scenarios, in which a vehicle approaches from the side on a straight road with a good view, was significantly higher in the pinhole 10° group than in the pinhole 15° group. CONCLUSIONS: Concentric constriction of the visual field was associated with increased number of traffic accidents. The simulation findings indicated that a visual field of 10° to 15° may be important for avoiding collisions in places where there is a straight road with a good view.

Biosignal-based relaxation evaluation of head-care robot.

Such popular head care procedures as shampooing and scalp massages provide physical and mental relaxation. However, they place a big burden such as chapped hands on beauticians and other practitioners. Based on our robot hand technology, we have been developing a head care robot. In this paper, we quantitatively evaluated its relaxation effect using the following biosignals: accelerated plethymography (SDNN, HF/TP, LF/HF), heart rate (HR), blood pressure, salivary amylase (sAA) and peripheral skin temperature (PST). We compared the relaxation of our developed head care robot with the head care provided by nurses. In our experimental result with 54 subjects, the activity of the autonomic nerve system changed before and after head care procedures performed by both a human nurse and our proposed robot. Especially, in the proposed robot, we confirmed significant differences with the procedure performed by our proposed head care robot in five indexes: HF/TP, LF/HF, HR, sAA, and PST. The activity of the sympathetic nerve system decreased, because the values of its indexes significantly decreased: LF/HF, HR, and sAA. On the other hand, the activity of the parasympathetic nerve system increased, because of the increase of its indexes value: HF/TP and PST. Our developed head care robot provided satisfactory relaxation in just five minutes of use.