Anticipatory Looking as an Index of Episodic Memory in Alzheimer's disease

2022 Fiscal Year Final Research Report

• Project/Area Number: 20K14264
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 10040:Experimental psychology-related
• Research Institution: Aichi Shukutoku University (2022); Ritsumeikan University (2021); Chuo University (2020)
• Principal Investigator: Hanazuka Yuki 愛知淑徳大学, 人間情報学部, 講師 (90867657)
• Project Period (FY): 2020-04-01 – 2023-03-31
• Keywords: 認知症 / 出来事の記憶 / アイトラッカー / 予測的視線

Outline of Final Research Achievements

Alzheimer's disease (AD) is a disorder in which individuals have difficulty maintaining event memory of "when," "where," "who," and "what" events. However, accurate diagnosis of event memory may be hampered by verbal deficiency, one of the other symptoms of AD, because conventional tests are based on verbal instructions by the examiner and verbal responses by the patient. Therefore, nonverbal methods are essential for the assessment of event memory in AD. In the present study, we used eye tracking to examine whether AD patients develop anticipatory looking for future event-related actions based on past experiences when presented with the same video twice. The results revealed that AD patients showed anticipatory looking, although they were unable to verbally report the content of the video. These results indicate that AD patients have better one-time event memory than previously thought.

Free Research Field

実験心理学

Academic Significance and Societal Importance of the Research Achievements

認知症患者の記憶機能を調べる従来の検査法は対象者の言語的な反応を指標としたものが多く、言語機能が低下している患者においては記憶機能を過小評価してしまう可能性があった。しかし視線という非言語性の指標を用いることで言語機能に依存せず、言語機能と記憶機能を区別して評価することが可能である。本研究ではこのような視点から、これまでエピソード記憶を保持できないと考えられてきた認知症者でも、言葉で表現することに制限があるだけで、日常的な記憶を有していることが示唆された。この成果は認知症の治療（リハビリの方針決め）や介護（日常生活における接し方）をするうえで有益かつ前向きになれるものであると考えられる。