滑動性追従眼球運動と視覚認知機能との関連

Relationship between smooth pursuit eye movement and visual perception

要旨：本研究の目的は，健常児・者の滑動性追従眼球運動(以下，SPEM)と視覚認知機能との関連を明らかにすることである．対象は健常成人10名，健常児10名で，SPEMの測定には，電気眼電位図(以下，EOG)を用い，SPEMの評価としてサッケード混入率を定量的に測定した．視覚認知機能の測定には，各視覚認知機能面の要素の異なる3つの机上検査を実施した．その結果，サッケード混入率では，本研究における9歳以上の健常児および健常成人の間では年齢による違いが見られなかった．またSPEMと視覚認知機能との関連では，サッケード混入率が高いほど視覚認知機能の低さが見られ，MT野，MST野との関連が示唆された．

　The purpose of this study is to describe the relationship between smooth pursuit eye movement (SPEM) and visual perception of normal adults and children using the electro-oculogram (EOG) and visual perception tests.

　The subjects were 10 normal adults of mean age 22.1±0.88, and 10 normal children of mean age 13.3±2.83.

　The Nistamograph EN1104 (NEC) was used for the visual stimuli, and as a measurement device of the EOG. A total of 6 trials were conducted with a combination of 10 degrees optic angle, 20 degrees and 30 degrees with two different speeds (0.142 Hz, 0.1 Hz). The subjects were instructed to pursue the target only with eyes. The SPEM was measured with AC-EOG and 8 mm video camera at the same time, using EOG for a quantitative measurement of the ocular motility for the saccade mixing rate in SPEM. For the tests of visual perception abilities, a visual-motor coordination test of Frostig Developmental Screening Test, space visualization test and design copying test of the Southern California Sensory Integration Tests (SCSIT) were used.

　The results suggest no difference with regard to age among normal children and normal adults of nine years or more. The low degree of the visual perception abilities and the high saccade mixing rate took place in the Medial Temporal area. In addition, the Medial Superior Temporal area was suggested from the relationship between SPEM and the visual perception abilities.