Chong J, Triggs T J
Hum Factors. 1989 Feb;31(1):63-75. doi: 10.1177/001872088903100105.
The visual environment of a driver in a car or a pilot in an airplane has intervening objects from the vehicle such as A-pillar posts between the windscreen and the doors in the car or cockpit pillars in the airplane. The presence of such objects can bias the observer's visual accommodation response because of the Mandelbaum effect (e.g., Owens, 1979). When subjects were allowed to focus toward a distance by looking through a large aperture in an intervening post, the detection (monocular) of a briefly presented distant target was found to be significantly better than when no aperture was present. When the size of the aperture was decreased from 2.3 to 1.15 deg diameter, target detection performance was significantly decreased and remained constant as further reduction of foveal cues was made. Although the detection results were generally in agreement with the visual accommodation results, detection accuracy changed significantly only with marked changes in accommodation. In addition to an accommodation bias, interference to target detection was also observed for those targets occurring at a laterally proximal position to the intervening object.
汽车驾驶员或飞机飞行员的视觉环境中存在来自车辆的遮挡物体，例如汽车挡风玻璃和车门之间的A柱，或飞机驾驶舱的支柱。由于曼德尔鲍姆效应（例如，欧文斯，1979年），这些物体的存在会使观察者的视觉调节反应产生偏差。当受试者通过遮挡柱上的大孔径看向远处时，发现短暂呈现的远处目标的检测（单眼）明显优于没有孔径时。当孔径大小从直径2.3度减小到1.15度时，目标检测性能显著下降，并且随着中央凹线索的进一步减少而保持不变。尽管检测结果总体上与视觉调节结果一致，但检测准确性仅在调节有显著变化时才会发生显著变化。除了调节偏差外，还观察到对于出现在遮挡物体横向近端位置的目标，对目标检测存在干扰。
