Visuospatial perception processes of subjective visual vertical in patients with unilateral spatial neglect.

2023 Fiscal Year Final Research Report

• Project/Area Number: 21K17480
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 59010:Rehabilitation science-related
• Research Institution: Kansai Medical University
• Principal Investigator: Mori Kimihiko 関西医科大学, リハビリテーション学部, 助教 (10890890)
• Project Period (FY): 2021-04-01 – 2024-03-31
• Keywords: 半側空間無視 / 主観的視覚性垂直

Outline of Final Research Achievements

We analyzed subjective visual vertical (SVV) judgments of vertical orientation in patients with unilateral spatial neglect. When presented with a vertical frame as a visual cue, we found a reduction in SVV deviation and variability in judgment when starting from the neglected side, which is characteristic of patients with unilateral spatial neglect.
Furthermore, analysis of eye movements for judging vertical showed that patients with unilatelal spatial neglect tended to fix their eye position on a specific part of the target not only on the neglected side but also on the non-neglected side, with less amount and frequency of eye movements, and symptoms characteristic of unilateral spatial neglect were also observed in SVV. These differences in eye movements were characterized by the presence or absence of damage to brain regions responsible for exploratory eye movements.

Free Research Field

脳卒中

Academic Significance and Societal Importance of the Research Achievements

半側空間無視患者における主観的視覚性垂直はこれまでにも多く報告されていたが、特に視線移動に特徴づけられる病態に対して、視線解析に基づく垂直判断の定量化はできていなかった。本研究では、主観的視覚性垂直における視線移動パターンを初めて明らかにし、その特徴は脳の損傷領域の機能障害に対しても支持できるものであった。さらに、半側空間無視により視空間性の知覚の障害があったとしても、視覚的手がかりが無視側からの偏倚と変動性を減少させる変調メカニズムは、臨床的に有用な視線誘導法を提案することを可能にし、半側空間無視患者の姿勢障害に対する新たなリハビリテーションに役立つ知見として社会的意義が高い。