健常者とパーキンソン病患者のリズム記憶の特徴—干渉刺激が与える影響

Characteristics of the rhythmic memory of healthy subjects and Parkinson's patients: Effects of auditory interference stimuli

要旨：本研究は，健常者とパーキンソン病（Parkinson's Disease；以下，PD）患者の短期的なリズム記憶・再生に干渉刺激が及ぼす影響について，1.0 Hzのリズム再生課題を用いて検討した．干渉刺激は，無意味刺激と有意味刺激の2種類とし，干渉刺激のない場合との比較を行った．リズム再生課題の結果，干渉刺激のない場合にPD患者で有意にリズム再生の正確性が低下した．また，干渉刺激の影響においては，無意味刺激のある場合は，すべての群で差は認められなかったが，有意味刺激のある場合は，PD患者で有意に干渉刺激の影響をうける結果となった．この結果より，PD患者は，有意味刺激が多い日常生活場面では，正確なリズム再生が困難となることが示唆された．

　This study investigated the influence of auditory interference stimuli on short-term rhythm memory and reproduction of healthy subjects and Parkinson's disease patients (PD patients) through the 1.0 Hz rhythm reproduction task. Task performance with two types of auditory interference stimuli, either meaningless or meaningful, was compared with performance in the absence of interference stimuli. The results of the rhythm reproduction task showed that the accuracy of rhythm reproduction decreased significantly in PD patients in the absence of interference stimuli. Regarding the effect of auditory interference stimuli, no difference was observed in any of the groups in the presence of a meaningless interference stimulus. In contrast, PD patients were significantly affected by the presence of a meaningful interference stimulus. These results suggest that PD patients experience difficulty in reproducing accurate rhythm in their daily lives where various meaningful stimuli are present.