The Eye Movement Study Of Perceptual Span From First Grades To Fifth Grades

Reading is an important way for human to obtain information,and eye movement measures are microcosmic,dynamic and sensitive.The perceptual span in reading is defined as the amount of obtaining useful information at a single fixation.In this study,the eye-movement-contingent display changes technique is used to investigate the development of perceptual span of students.The window condition and the grade are independent variables,and eye movement measures are all dependent variables.Window size had been designed asymmetrically,and the number of window conditions are increased with grades:there are four window conditions in Grade 1(R0?L1R1?LIR2?FL),five window conditions in Grade 2(R0?LI R1?L1R2>L1R3>FL),and six window conditions in Grade 3 to Grade 5(R0?L1R1?L1R2?L1R3?L1R4?FL).The grade variable includes five levels,Grade 1 to Grade 5.There are 153 participants totally.The dependent variables,eye movement measures,include reading rate,average fixation duration and rightward saccade amplitude.The perceptual span of students is identified by reading rate.According to the reading rate of every grade students at full line condition(FL),the method of median segmentation is adopted to divide every grade students into faster readers and slower readers after experiment--faster readers' reading rate at full line condition are all higher than median while slower readers' reading rate at full line condition are all lower than median--to investigate the differences of perceptual span between faster readers and slower readersOur experimental results include three parts:the first part is development of perceptual span with grades;the second part is to determine the size of perceptual span in every grade;the last part is the differences of perceptual span between faster readers and slower readers.The results are as follows:(1)The size of perceptual span of students is three characters(L1R1)in Grade 1,four characters(L1R2)in Grade 2 to Grade 5(2)If students of every srade are divided into faster readers and slower readers,we find that there have no differences between faster readers' and slower readers' perceptual span in Grade 1--both are three characters(L1R1);faster readers' and slower readers' perceptual span have differences from Grade 2 to Grade 5--faster readers' perceptual span is five characters(L1R3)and slower readers' perceptual span is three characters(L1R1).Conclusion:(1)The perceptual span become larger with grades,and the key point of development of perceptual span is in the period from Grade 1 to Grade 2(2)Children' development of perceptual span is a process,which is from symmetrically to asymmetrically.