Whitford Thomas J, Rennie Christopher J, Grieve Stuart M, Clark C Richard, Gordon Evian, Williams Leanne M
Brain Dynamics Centre, Westmead Millennium Institute, University of Sydney, Westmead Hospital, New South Wales, Australia.
Hum Brain Mapp. 2007 Mar;28(3):228-37. doi: 10.1002/hbm.20273.
Adolescence to early adulthood is a period of dramatic transformation in the healthy human brain. However, the relationship between the concurrent structural and functional changes remains unclear. We investigated the impact of age on both neuroanatomy and neurophysiology in the same healthy subjects (n = 138) aged 10 to 30 years using magnetic resonance imaging (MRI) and resting electroencephalography (EEG) recordings. MRI data were segmented into gray and white matter images and parcellated into large-scale regions of interest. Absolute EEG power was quantified for each lobe for the slow-wave, alpha and beta frequency bands. Gray matter volume was found to decrease across the age bracket in the frontal and parietal cortices, with the greatest change occurring in adolescence. EEG activity, particularly in the slow-wave band, showed a similar curvilinear decline to gray matter volume in corresponding cortical regions. An inverse pattern of curvilinearly increasing white matter volume was observed in the parietal lobe. We suggest that the reduction in gray matter primarily reflects a reduction of neuropil, and that the corresponding elimination of active synapses is responsible for the observed reduction in EEG power.
从青春期到成年早期，健康的人类大脑会经历巨大的转变。然而，同时发生的结构和功能变化之间的关系仍不清楚。我们使用磁共振成像（MRI）和静息脑电图（EEG）记录，研究了年龄对10至30岁的同一组健康受试者（n = 138）的神经解剖学和神经生理学的影响。MRI数据被分割为灰质和白质图像，并被划分为大规模感兴趣区域。对每个脑叶在慢波、α和β频段的绝对EEG功率进行了量化。发现额叶和顶叶皮质的灰质体积在整个年龄段中减少，最大的变化发生在青春期。EEG活动，特别是在慢波频段，在相应的皮质区域显示出与灰质体积相似的曲线下降。在顶叶观察到白质体积呈曲线增加的相反模式。我们认为灰质的减少主要反映了神经毡的减少，并且观察到的EEG功率降低是由活跃突触的相应消除所致。
