ヤマナカ ケンタロウ    YAMANAKA Kentarou
   山中 健太郎
   所属
生活科学部 健康デザイン学科
 
生活機構研究科 生活科学研究専攻
 
生活機構研究科 生活機構学専攻
 
女性健康科学研究所 所属教員
   職種
教授
言語種別 英語
発行・発表の年月 2016/11
形態種別 学術雑誌
査読 査読あり
標題 Intentional gaze shift to neglected space: a compensatory strategy during recovery process after unilateral spatial neglect.
執筆形態 共著
掲載誌名 Brain
掲載区分国外
出版社・発行元 Oxford University Press
巻・号・頁 139(11),pp.2970-2982
著者・共著者 Takamura Y. Imanishi M. Osaka M. Ohmatsu S. Tominaga T. Yamanaka K. Morioka S. Kawashima N.
概要 Unilateral spatial neglect is a common neurological syndrome following predominantly right hemispheric stroke. While most patients lack insight into their neglect behaviour and do not initiate compensatory behaviours in the early recovery phase, some patients recognize it and start to pay attention towards the neglected space. We aimed to characterize visual attention capacity in patients with unilateral spatial neglect with specific focus on cortical processes underlying compensatory gaze shift towards the neglected space during the recovery process. Based on the Behavioural Inattention Test score and presence or absence of experience of neglect in their daily life from stroke onset to the enrolment date, participants were divided into USN++ (do not compensate, n = 15), USN+ (compensate, n = 10), and right hemisphere damage groups (no neglect, n = 24). The patients participated in eye pursuit-based choice reaction tasks and were asked to pursue one of five horizontally located circular objects flashed on a computer display. The task consisted of 25 trials with 4-s intervals, and the order of highlighted objects was randomly determined. From the recorded eye tracking data, eye movement onset and gaze shift were calculated. To elucidate the cortical mechanism underlying behavioural results, electroencephalagram activities were recorded in three USN++, 13 USN+ and eight patients with right hemisphere damage. We found that while lower Behavioural Inattention Test scoring patients (USN++) showed gaze shift to non-neglected space, some higher scoring patients (USN+) showed clear leftward gaze shift at visual stimuli onset. Moreover, we found a significant correlation between Behavioural Inattention Test score and gaze shift extent in the unilateral spatial neglect group (r = −0.62, P < 0.01). Electroencephalography data clearly demonstrated that the extent of increase in theta power in the frontal cortex strongly correlated with the leftward gaze shift extent in the USN++ and USN+ groups. Our results revealed a compensatory strategy (continuous attention to the neglected space) and its neural correlates in patients with unilateral spatial neglect. In conclusion, patients with unilateral spatial neglect who recognized their own neglect behaviour intentionally focused on the neglected space as a compensatory strategy to avoid careless oversight.
DOI 10.1093/brain/aww226