Babiloni Claudio, Albertini Giorgio, Onorati Paolo, Vecchio Fabrizio, Buffo Paola, Sarà Marco, Condoluci Claudia, Pistoia Francesca, Carducci Filippo, Rossini Paolo M
Department of Biomedical Sciences, University of Foggia, Italy.
Clin Neurophysiol. 2009 Sep;120(9):1619-27. doi: 10.1016/j.clinph.2009.06.017. Epub 2009 Jul 29.
We tested the hypothesis that inter-hemispheric directional functional coupling of eyes-closed resting EEG rhythms is abnormal in adolescents with Down syndrome (DS).
Eyes-closed resting EEG data were recorded in 38 DS adolescents (18.7 years +/-0.67 SE, IQ=49+/-1.9 SE) and in 17 matched normal control subjects (NYoung=19.1 years +/-0.39 SE). The EEG data were recorded from 8 electrodes (Fp1, Fp2, C3, C4, T3, T4, O1, O2) referenced to vertex. EEG rhythms of interest were delta (2-4 Hz), theta (4-8 Hz), alpha 1 (8-10.5 Hz), alpha 2 (10.5-13 Hz), beta 1 (13-20 Hz), and beta 2 (20-30 Hz). Power of EEG rhythms was evaluated by FFT for control purposes, whereas inter-hemispheric directional EEG functional coupling was computed by directed transfer function (DTF).
As expected, alpha, beta, and gamma power was widely higher in NYoung than DS subjects, whereas the opposite was true for delta power. As a novelty, DTF (directionality) values globally prevailed from right to left occipital areas in NYoung subjects and in the opposite direction in DS patients. A control experiment showed that this DTF difference could not be observed in the comparison between DS adults with mild cognitive impairment and normal age-matched adults.
These results indicate a peculiar abnormal directional inter-hemispheric interplay in visual occipital areas of DS adolescents.
Direction of inter-hemispheric EEG functional coupling unveils a new abnormal brain network feature in DS adolescents.
我们检验了这样一个假设，即唐氏综合征（DS）青少年闭眼静息脑电图节律的半球间定向功能耦合异常。
记录了38名DS青少年（18.7岁±0.67标准误，智商=49±1.9标准误）和17名匹配的正常对照受试者（NYoung=19.1岁±0.39标准误）的闭眼静息脑电图数据。脑电图数据从8个电极（Fp1、Fp2、C3、C4、T3、T4、O1、O2）记录，以头顶为参考。感兴趣的脑电节律为δ波（2 - 4赫兹）、θ波（4 - 8赫兹）、α1波（8 - 10.5赫兹）、α2波（10.5 - 13赫兹）、β1波（13 - 20赫兹）和β2波（20 - 30赫兹）。为了进行对照，通过快速傅里叶变换评估脑电节律的功率，而通过定向传递函数（DTF）计算半球间定向脑电功能耦合。
正如预期的那样，NYoung组受试者的α波、β波和γ波功率普遍高于DS组受试者，而δ波功率则相反。新奇的是，DTF（方向性）值在NYoung组受试者中总体上从右侧枕叶区域向左侧枕叶区域占优势，而在DS患者中则相反。一项对照实验表明，在轻度认知障碍的DS成年人与年龄匹配的正常成年人的比较中未观察到这种DTF差异。
这些结果表明DS青少年视觉枕叶区域存在特殊的异常半球间定向相互作用。
半球间脑电功能耦合的方向揭示了DS青少年一种新的异常脑网络特征。
