| Motion perception is an essential skill for individuals in everyday life,and the ability to estimate when a moving object has reached a given position is a very important one.In real-life situations,the perception of the motion of an object is usually accomplished in response to various visual surroundings.As a common form of illusion,horizontal and vertical illusions,two equal line segments differ in their orientation and structure affecting an individual’s perception,this study explores the differences in time-to-collision(TTC)performance by constructing two backgrounds,horizontal and vertical,with different line segment orientations.The use of three-dimensional zebra crossings in many areas of domestic and overseas to alert drivers to the need for timely braking behavior.The study will also investigate whether the depth perceptions induced by the three-dimensional markings can influence drivers’ accurate judgments.The present study based on the occlusion paradigm to investigate whether different background information and motion speeds affect the trend and accuracy of TTC estimation when stimuli move in a plane parallel to the observer.Experiment 1 used 2(background orientations: horizontal,vertical)× 3(motion speeds: slow 100pixel/s,medium 200pixel/s,fast 300pixel/s)two factor within-subjects experimental design to explore the effect of different line orientations and motion speeds on TTC performance;Experiment 2 used 2(background dimensions: two-dimensional background,threedimensional background)× 3(motion speeds: slow 100pixel/s,medium 200pixel/s,fast300pixel/s)two factor within-subjects experimental design to explore the effects of different background dimensions and motion speeds on the performance of TTC estimation.It was found that TTC were underestimated for the slow speed condition and overestimated for the medium and fast speed conditions.The highest accuracy of TTC estimation was found for the fast condition.TTC were overestimated in the vertical background condition and underestimated in the horizontal background condition.There was an interaction between motion speed and background orientation,TTC were estimated more accurately for the vertical line segment background in the slow condition and for the horizontal line segment background in the medium speed condition.Compared to the two-dimensional background,the three-dimensional background overestimated the TTC.Therefore,the main conclusions of this study are as follows:(1)Different motion speeds affect the performance of the TTC estimation.(2)Different backgrounds affect TTC estimation performance when the object is moving in a plane parallel to the observer.(3)Background orientations affect TTC estimation performance differently for different speeds of motion. |
