小学生在交通情境中的视觉搜索:发展的观点

The Development of Pupil's Visual Search in Traffic Situation

为探讨小学生在交通情境中的视觉搜索发展,研究以一、二、四和六年级小学生及成人为被试,采用"找不同"任务和过马路决策眼动任务进行实验。结果发现,一、二年级小学生"找不同"的效率低于成人;一年级小学生冒险及错失过马路比例均较高;小学生的眼跳特征与成人相似,但对兴趣区的关注低于成人;女生错失过马路比例高于男生,视觉搜索水平及搜索策略的性别差异不显著。研究表明,小学生的视觉搜索能力随年龄逐渐提高,但搜索的有效性低于成人,性别分化不明显。

Visual search is an important component of pedestrians’ interaction with traffic situation, which allowing them to successfully identify external cues that impact their decision-making. Previous research has identified that children under the age of 14 are particularly vulnerable to road accidents as pedestrians, and a number of motivational and cognitive skill factors which may play a part in it. Studies have shown that children with low visual search are more likely to take risks when crossing the road. However, in traffic situations, whether children’s level of visual search, and searching strategy is the same with that of the adults is less mentioned in previous studies. This study aims to explore the development of pupils’ visual search as pedestrians.The sample consisted of 160 Chinese pupils from a common primary urban school, including 42 in Grade 1, 43 in Grade 2, 41 in Grade 4 and 34 in Grade 6. In addition, 41 adult volunteers aged between 18 and 27 were recruited from a university in Nantong city. All subjects completed two experiments： ‘spot the difference’ was used to assess subject’s visual search ability, while visual search strategies were studied by analyzing the eye movements of the children and the adults while they were carrying out the video task. In experiment 1, there were 34 pairs of pictures chosen as stimulus materials, including 30 pairs for experiment and 4 pairs for practice. The subjects were asked to spot all the differences on each of the picture pairs as quickly as possible, but they were not told there were how many differences in each pair. In experiment 2, a simulated road environment of moving traffic was designed by video designers. The subjects’ eye movement was recorded by Smart Eye 3 D Eye Tracking System. Participants were instructed to observe the traffic video, and give a response when they thought it was safe to cross.The results showed that as pupils growing, their efficiency in ＂spot the differences＂ task improved continuously. However, pupils in grade 1 and 2 still did not perform as well as the adults,（p 〈.01）. The performance in ＂spot the differences＂ had no significant differences between boys and girls（p 〉.05）. Compared with adults, the pupils behaved much more in missing crossing and less in safety crossing（p 〈.05）. Specially, among the pupils, the pupils in grade 4 had the least times of adventure crossing, while missed the most times to cross the road（p 〈.05）. The girl’s missing crossing was much more than the boys（p 〈.01）. Pupils’ eye gaze in the region of interest were different from the adults’ in that the adults’ fixation duration was much longer than the pupils（p 〈.001）, and the fixation counts were much more than the pupils（p 〈.05）, except on the curve. However, pupils’ saccade amplitude and saccade velocity in the whole traffic video were not different from the adults’（p〉.05）.Results demonstrated that pupils’ traffic visual searching ability went up as they grew, and visual searching strategies became more reasonable and useful. However, they were still on a low level compared with adults. Visual search for grade 4 pupils（9~10 years of age） developed significantly. Visual search did not vary with gender on the whole.