轻度认知障碍患者言语流畅性下降的静息态功能磁共振研究

A resting-state fMRI study on the verbal fluency decline in mild cognitive impairment

目的采用低频振幅(amplitude of low frequency fluctuation,ALFF)初步探索轻度认知障碍(mild cognitive impairment,MCI)患者言语流畅性下降的脑机制。材料与方法前瞻性纳入20例MCI患者(MCI组)及16例性别、年龄、受教育程度相匹配的健康人作为对照组(健康对照组),入组前分别采集两组临床资料、神经心理学量表和静息态功能磁共振(resting-state functional magnetic resonance,rs-fMRI)数据。采取ALFF分析方法,比较MCI组与健康对照组静息态脑功能差异,并进一步采用Spearman相关分析分别观察ALFF变化的脑区与言语流畅性测试量表的相关性。结果与健康对照组比较,MCI组患者右侧岛叶/颞上回ALFF降低(高斯随机场校正,voxel P<0.005,cluster P<0.05)。未发现ALFF升高脑区。降低的ALFF值与蒙特利尔认知量表基础版的流畅性测试有显著的正相关性(r_(s)=0.500,P=0.025)。结论MCI存在右侧岛叶/颞上回大脑活动降低,可能是患者言语流畅性下降的原因。

Objective: Amplitude of low frequency fluctuation(ALFF) was used to preliminarily explore the brain mechanism of verbal fluency decline in patients with mild cognitive impairment(MCI). Materials and Methods: A total of 20 MCI patients(MCI group) and16 healthy controls(healthy controls group) matched in gender, age and education level were recruited prospectively. Before enrollment,clinical data, neuropsychological scales and resting-state functional magnetic resonance imaging data were collected. ALFF was used to compare the differences of resting-state brain function between MCI group and healthy controls group, and the Spearman correlation between the change brain regions of ALFF and verbal fluency scales was further observed. Results: Compared with the healthy control group, the ALFF of the right insula/superior temporal gyrus was decreased in MCI group(Gaussian random field correction, voxel P<0.005, cluster P<0.05). No ALFF elevation was found in brain regions. There was a significant positive correlation between reduced ALFF and fluency test of Montreal cognitive assessment-basic(r_(s)=0.500, P=0.025). Conclusions: MCI has decreased brain activity in the right insula/superior temporal gyrus, which may be underlying the mechanism of patient’s verbal fluency decline.