Friday Lunch Seminar (English)

February 3, 2023
12:15 〜 13:00
(On-line)

Talk Title:
Characteristics of visuospatial analyses during the measure of subjective visual vertical in subacute stroke patients

Kae Nakamura
Professor
Kansai Medical university

Host PI: Masahiko Haruno

Abstract:
Subjective visual vertical (VV), the visually estimated direction of gravity, has been measured as a clinical assessment of vestibular function and visuospatial cognition. It has been reported that stroke patients with unilateral spatial neglect (USN), characterized by attention deficits in the contralateral side of space, exhibit significantly greater deviation of orientation and larger variability of VV. However, the causes of changes in VV observed in the USN patients are unclear. By trial-by-trial analyses of VV measured in stroke patients with/without spatial neglect and normal controls, we discovered altered attentional updating mechanisms which significantly affect VV in the USN patients. Analyses of eye movement patterns during the measure of VV revealed a significantly reduced total scan length in USN patients (Mori, 2020). Further trial-by-trial analyses revealed that, although USN patients VV judgment was overall poor, trials with longer eye-scan lengths were associated with better VV judgment. Lesion anatomy revealed that such compensation of VV by longer scan length was observed for patients without, not with, frontal lobe lesions, suggesting the contribution of the frontal visuospatial updating process. The results demonstrate a dysfunctional updating process of integration between vestibular and visuospatial information in the USN.