Rosengren Sally M, Nham Benjamin, Lim Jasmine, Parlane Rengen, Dyball Alyssa C, Reid Nicole, Halmagyi G Michael, Welgampola Miriam S
Neurology Department, Royal Prince Alfred Hospital, Level 8, Missenden Rd, Camperdown, NSW, 2050, Australia.
Central Clinical School, University of Sydney, Sydney, Australia.
J Neurol. 2024 Dec 16;272(1):66. doi: 10.1007/s00415-024-12844-w.
Number magnitude is often represented spatially in the mind by a mental number line, on which small numbers are located to the left of space and large numbers to the right. As vestibular dysfunction can affect aspects of spatial cognition, we wondered whether patients with acute vestibular loss would show a directional bias along the mental number line.
We gave 18 patients with vestibular neuritis (VN) (eight left VN, ten right; mean age 54 years, range 31-75 years; four females) and 15 normal age- and education-matched controls (mean age 47 years, range 26-75 years; 11 females) a mental number bisection task.
The patients with left VN underestimated the middle number (mean sum of signed errors -3.3, SE 1.5), while patients with right VN overestimated it (mean 1.9, SE 0.7). The direction of effect aligned with the direction of slow phase velocity. The results for the normal controls fell in between the two patient groups, and represented an underestimate of the middle number (mean -1.5, SE 0.8). In the patients, the effect was greater without visual fixation and in the acute stage compared to 1 or 2 weeks later. The error rates were similar across all groups and conditions.
Our results show that acute vestibular loss produces a temporary directional bias in numerical processing that is only present in the absence of visual cues. The effect is similar to that seen in patients with visuospatial neglect.
数字大小在脑海中通常由心理数字线以空间形式呈现，在这条线上，较小的数字位于空间左侧，较大的数字位于右侧。由于前庭功能障碍会影响空间认知的各个方面，我们想知道急性前庭功能丧失的患者在心理数字线上是否会表现出方向偏差。
我们让18例前庭神经炎（VN）患者（8例左侧VN，10例右侧；平均年龄54岁，范围31 - 75岁；4例女性）和15名年龄及教育程度匹配的正常对照者（平均年龄47岁，范围26 - 75岁；11例女性）完成一项心理数字二等分任务。
左侧VN患者低估了中间数字（符号误差总和的平均值为 -3.3，标准误为1.5），而右侧VN患者高估了中间数字（平均值为1.9，标准误为0.7）。效应方向与慢相速度方向一致。正常对照组的结果介于两组患者之间，表现为对中间数字的低估（平均值为 -1.5，标准误为0.8）。在患者中，与1或2周后相比，在无视觉注视和急性期时效应更大。所有组和条件下的错误率相似。
我们的结果表明，急性前庭功能丧失在数字处理中产生了一种暂时的方向偏差，这种偏差仅在没有视觉线索时出现。这种效应与视觉空间忽视患者中观察到的效应相似。
