Tekes Aylin, Mohamed Mona A, Browner Nina M, Calhoun Vince D, Yousem David M
Johns Hopkins Hospital, The Russell H. Morgan Department of Radiology and Radiological Sciences, Division of Neuroradiology, 600 N. Wolfe Street/ Phipps B-112, Baltimore, MD 21287, USA.
Acad Radiol. 2005 Jun;12(6):739-45. doi: 10.1016/j.acra.2004.08.015.
We sought to determine the effect of age on functional MR imaging experiments performed with visual and motor stimulation. We hypothesized that there would be a diminution in the amplitude of fMRI activation with increasing subjects' age.
We used fixed effects models to study the amplitude of activation during a block design visuomotor task in three different age groups: old (mean: 75 years; standard deviation: 6 years), middle-aged (mean: 52 years; standard deviation: 9 years) and young (mean: 29 years; standard deviation: 5 years). Each group included 7 subjects. Regions of interest (ROI) were left primary motor area (LM1), supplementary motor area (SMA), and right and left occipital (RO, LO) visual areas. Individual subjects and group statistical parametric maps (SPMs) were generated for each ROI, and then the mean amplitude of activation was compared using the group analysis and t test.
The young age group showed higher amplitude of activation than middle and old age groups in all ROI (P < 0.01 uncorrected). Unpaired two tailed t test results between the groups showed significant differences between middle and young, and old and young age groups in all ROIs (P < or = 0.05), with the exception of old and young age groups in RO region (P = 0.11).
The group analysis, and unpaired t test results reveal higher amplitude of fMRI activation in the young versus the old and middle-aged groups.
我们试图确定年龄对视觉和运动刺激下的功能磁共振成像实验的影响。我们假设随着受试者年龄的增加，功能磁共振成像激活的幅度会减小。
我们使用固定效应模型研究了三个不同年龄组在组块设计的视觉运动任务期间的激活幅度：老年组（平均：75岁；标准差：6岁）、中年组（平均：52岁；标准差：9岁）和青年组（平均：29岁；标准差：5岁）。每组包括7名受试者。感兴趣区域（ROI）为左侧初级运动区（LM1）、辅助运动区（SMA）以及右侧和左侧枕叶视觉区（RO、LO）。为每个ROI生成个体受试者和组统计参数图（SPM），然后使用组分析和t检验比较激活的平均幅度。
在所有ROI中，青年组的激活幅度均高于中年组和老年组（未校正P<0.01）。组间未配对双尾t检验结果显示，除RO区域的老年组和青年组外（P = 0.11），所有ROI的中年组与青年组、老年组与青年组之间均存在显著差异（P≤0.05）。
组分析和未配对t检验结果显示，青年组功能磁共振成像激活幅度高于老年组和中年组。
