図形特質に対する注視傾向 : 痴呆性老人と精神薄弱者の視覚情報探索行動に関する研究,第1報

Abstract

This is an experimental study to investigate eye fixation behaviors in the senile elderly and the mentally retarded. Eye fixations of 7 senile elderly, 10 mentally retarded and 10 normal adults are recorded by a reflection eye camera while they are looking at series of presentation. The presentation is given by abstract figures, represented in walking environment, such as boundary, refraction, continuity, direction, flashing, movement and signal. Fixation behaviors are analysed with eye fixation time, range and scan path by a 10X8 or 10 X 7 segmental grid sheet. The results are summarized as follows. 1) The range of fixation points and scan paths in the senile elderly is more limited and biased to the center of presenting figures than in the mentally retarded and nomal adults. 2) The senile elderly and the mentally retarded show less fixation time than normal adults on portions representing boundary and refraction. 3) Eye search in the senile elderly and the mentally retarded appears less efficient in limited time due to their longer duration of a fixation point, which is over 4 seconds at maximum. 4) The senile elderly and the mentally retarded increase fixation time on the same portions in case of being given clear contrast on ground. 5) Normal adults can persue most of dynamic figures. The senile elderly and the mentally retarded can also persue some of dynamic figures, although with respectively lower and the lowest degree among 3 groups. Therefore, it is suggested that the level of perception in the senile elderly and the mentally retarded can be raised by emphasis of visual stimulus such as clear contrast and dynamic objects.