A substantial proportion of patients with Lewy body disease experience a variety of false perceptions, which include visual hallucinations of persons and animals, a sense of presence, passage hallucinations and various types of visual illusions. My colleagues and I have been conducting behavioral and neuroimaging studies to investigate common mechanisms underlying these phenomenologically diverse misperception symptoms. In this paper, I present the findings obtained from these studies and discuss psychological and neural mechanisms of false perceptions in Lewy body disease with referring to the concept of “sense of veridicality”.

高齢期に生じる軽度認知障害が運転技能および運転行動に与える影響を理解するため, 65歳以上の運転者を対象とした追跡調査 (The study of Driving Risk and Individual Variables for Elderly drivers: DRIVE study)を進めている。調査は1.5年毎に行う施設調査と半年毎に行われる郵送調査とから成るが, 今回はベースライン調査で得られた情報に基づき報告する。