EEG Coherence

Continuous EEG was recorded using a 32-channel ActiveTwo BioSemi system (Amsterdam, Netherlands), configured to the standard International 10-20 System (channels: 28 lateral channels FP1/2; F7/8; F3/4; AF3/4; FC1/2, FC5/6, C3/4, T7/8, CP1/2, CP5/6, P3/4, P7/8, O1/2, PO3/4, plus 4 midline channels Fz, Cz, Pz, Oz). For some children, an additional eye-electrode was placed behind the child’s left eye (Ex3), and/or additional loose electrodes were positioned at the mastoids (Ex1-2). Electrodes offset were less than 20μv. The EEG data were recorded relative to common mode sense and driven right leg (CMS/DRL) electrodes placed near Cz. Continuous EEG was acquired at a 2048Hz sample rate using Actiview (version 7.05) from a Dell latitude E5540 laptop (operating system Windows 10 Professional; in lab 0.41 version details: i5-4310U CPU @ 2,00 GHz 2,60GHz 8GB; in lab 0.42, version details: i3-4010U CPU @ 1,70 GHz 1,70GHz 4GB). Tasks were programmed in Matlab using Psych-Toolbox 3 (Brainard & Vision, 1997) from a second laptop (MacBookPro 11,1 13 inch retina OSX 10.9.5 Intel Core i7 2,8 GHz 16GB 1600 MHz DDR3).

本研究采用32通道ActiveTwo BioSemi型脑电采集系统（产自荷兰阿姆斯特丹），按照国际标准10-20系统配置电极通道，共包含28个侧列电极（FP1/2、F7/8、F3/4、AF3/4、FC1/2、FC5/6、C3/4、T7/8、CP1/2、CP5/6、P3/4、P7/8、O1/2、PO3/4）以及4个中线电极（Fz、Cz、Pz、Oz）。针对部分儿童受试者，额外在其左眼后方放置眼电电极（编号Ex3），并/或在乳突位置安置额外的松散电极（编号Ex1-2）。所有电极偏移量均小于20μV。脑电数据以放置于Cz附近的共模检测（common mode sense, CMS）与驱动右腿（driven right leg, DRL）电极作为参考进行采集。连续脑电信号以2048Hz的采样率，通过Actiview软件（版本7.05）进行采集，所用硬件为Dell Latitude E5540笔记本电脑（操作系统为Windows 10专业版；其中实验室0.41版本的配置详情为：i5-4310U CPU @ 2.00GHz 2.60GHz，8GB内存；实验室0.42版本的配置详情为：i3-4010U CPU @ 1.70GHz 1.70GHz，4GB内存）。实验任务通过第二台笔记本电脑运行，该电脑为MacBookPro 11.1 13英寸视网膜屏机型，搭载OSX 10.9.5系统、Intel Core i7 2.80GHz处理器、16GB 1600MHz DDR3内存；实验程序基于Matlab平台，使用Psych-Toolbox 3工具包编写（Brainard & Vision, 1997）。