自閉症スペクトラム障害の簡易精神機能テスト(臺)の結果

Autonomic and Motor Responses to Utena's Simple Psychic Function Test in Autism Spectrum Disorder

抄録

　20名の自閉症スペクトラム障害患者(ASD群)および年齢と性をほぼ一致させた同数の健常者に対して，臺の考案した簡易精神機能テストおよび乱数生成時の心電図R-R間隔の測定を行った。迷走神経系の指標は安静時も課題施行時もともにASD群が有意に低く，また乱数生成時の心拍数の増加がなく，自律神経系の機能障害が示唆された。運動機能はASD群で有意に悪く，計画(planning)の段階の障害が示唆された。乱数生成課題の結果と年齢および知能指数との相関は両群で正反対であった。ASDは高次の認知過程(思考系)だけでなく，自律神経系(入力系)および運動系(出力系)にもなんらかの障害のあることを示唆した。

　Objective：To evaluate autonomic nervous function, motor function, executive function and symbolization in autism spectrum disorder(ASD)using mainly Utena's simple psychic function test.

　Methods：Twenty adolescents and adults with ASD and 20 healthy persons matched in age and sex were examined.

　Results：Cardiac vagal index derived from a nonlinear plot of RR intervals showed autonomic hyperarousal in ASD subjects, though there were no group differences in cardiac sympathetic index. Pulse rates increased significantly in a random number generation task more than in a simple mental task in healthy control subjects, although no difference was found in ASD subjects in pulse rates according to these tasks. These findings may imply autonomic dysregulation in ASD. Reaction time to a motor function test was significantly longer in ASD subjects than in healthy control subjects. This may imply a deficit not of motor execution but of motor planning in ASD. Valuables of executive function derived from a random number generation task had a significantly negative linear correlation not with age but with IQ in ASD subjects, though the opposite results were shown in healthy control subjects. In the control subjects, the valuables had significantly negative correlation not with IQ but with age. These findings may imply the differences of cognitive process of random number generation in both groups.

　Conclusion：ASD may have deficits in not only higher-level cognitive functions but also autonomic and motor functions.