Sheffield Cognition and Neuroimaging Laboratory (SCANLab), Academic Clinical Psychiatry, University of Sheffield, The Longley Centre, Sheffield, UK.
Dement Geriatr Cogn Disord. 2010;29(2):176-88. doi: 10.1159/000275674. Epub 2010 Mar 6.
BACKGROUND/AIMS: Visuospatial impairments are known to occur in Alzheimer's disease (AD). We hypothesised that functional magnetic resonance imaging (fMRI) response in task-related brain regions would be impaired in patients with AD during the task and that treatment with acetyl cholinesterase inhibitors would enhance activations in brain regions concerned with this visual perceptual processing.
Ten AD subjects were neuropsychologically assessed and underwent fMRI imaging whilst performing a series of visuospatial perception tasks, before and after treatment with acetyl cholinesterase inhibitors. Eleven healthy elderly comparison subjects were also scanned twice.
Regions of increased brain activation in AD included the left precuneus, left cuneus, left supramarginal gyrus, right parieto-temporal cortex and right inferior parietal lobule. Further, increased activation in the left precuneus was found to correlate significantly with improved functioning of activities of daily living.
We believe this to be the first fMRI study that, after controlling for the confound of repeat scanning, demonstrates altered patterns of brain activation associated with visuospatial processing following treatment in patients with AD. The treatment-related improvement of visual perception in AD may rely on enhanced attentional mechanisms, thereby possibly supporting independent living through improvement on activities of daily living.
背景/目的:已知阿尔茨海默病(AD)患者存在视觉空间障碍。我们假设 AD 患者在执行任务时,与任务相关的大脑区域的功能磁共振成像(fMRI)反应会受到损害,而乙酰胆碱酯酶抑制剂的治疗会增强与这种视觉感知处理相关的大脑区域的激活。
10 名 AD 患者进行神经心理学评估,并在接受乙酰胆碱酯酶抑制剂治疗前后进行 fMRI 成像,以执行一系列视觉空间感知任务。11 名健康老年对照组也进行了两次扫描。
AD 患者大脑激活增加的区域包括左楔前叶、左楔叶、左缘上回、右顶颞叶皮质和右下顶叶。此外,还发现左楔前叶的激活增加与日常生活活动功能的改善显著相关。
我们认为这是第一项在控制重复扫描混杂因素后,通过 fMRI 研究证明 AD 患者治疗后与视觉空间处理相关的大脑激活模式发生改变的研究。AD 患者的视觉感知治疗相关改善可能依赖于增强的注意力机制,从而可能通过改善日常生活活动来支持独立生活。