観念失行―使用失行―のメカニズム

Apraxia of object use (ideational apraxia) and its mechanism

I．本稿で扱う観念失行の定義

　使用すべき道具の認知は保たれており，運動遂行能力にも異常がないのに，道具の操作に失敗する状態・使用のまずさ（運動拙劣症）によるのでなく，使用に際しての困惑，誤りによる障害（山鳥，1985）。

　単一物品の操作でも複数物品を用いる複雑な操作でもみられるが，複数物品操作の方が出現しやすい。

The clinical entity of ideational apraxia (IA) continues to be ambiguous. Some voiced their doubts about its purity. Among scholars who recognize its independence as a syndrome their definition of IA remains divided. Poeck for example defined it as a sequencing disorder in the conceptual organization of complex actions and deals with behavior disorders associated with use of plural objects. De Renzi defined it as a disorder of the ideational plan of action manifesting itself through the faulty use ofobjects.