Donders Institute for Brain, Cognition, and Behaviour, Radboud University Nijmegen, 6525 EN Nijmegen, The Netherlands.
J Neurosci. 2012 Mar 7;32(10):3388-92. doi: 10.1523/JNEUROSCI.5592-11.2012.
Many aspects of brain processing are intimately linked to brain rhythms. Essentially all classical brain rhythms, i.e., delta, theta, alpha, beta, and sleep waves, are highly heritable. This renders brain rhythms an interesting intermediate phenotype for cognitive and behavioral traits. One brain rhythm that has been particularly strongly linked to cognition is the gamma rhythm: it is involved in attention, short- and long-term memory, and conscious awareness. It has been described in sensory and motor cortices, association and control structures, and the hippocampus. In contrast to most other brain rhythms, the gamma frequency highly depends on stimulus and task conditions, suggesting a low heritability. However, the heritability of gamma has not been assessed. Here, we show that visually induced gamma-band synchronization in humans is strongly genetically determined. Eighty twin subjects (20 monozygotic and 20 dizygotic twin pairs) viewed a moving sinusoidal grating while their brain activity was recorded using magnetoencephalography. The stimulus induced spectrally confined gamma-band activity in sensors over visual cortex in all subjects, with individual peak frequencies ranging from 45 to 85 Hz. Gamma-band peak frequencies were highly correlated across monozygotic twins (r = 0.88), but not across dizygotic twins (r = 0.32) or unrelated subjects (r = 0.02). This implies a heritability of the gamma-band frequency of 91%. This strong genetic determination suggests that gamma-related cognitive functions are under close genetic control.
大脑处理的许多方面都与脑节律密切相关。本质上，所有经典的脑节律，即δ波、θ波、α波、β波和睡眠波，都具有高度的遗传性。这使得脑节律成为认知和行为特征的一个有趣的中间表型。与认知特别密切相关的一种脑节律是γ节律：它参与注意力、短期和长期记忆以及意识。它已在感觉和运动皮层、联合和控制结构以及海马体中被描述。与大多数其他脑节律不同，γ频率高度依赖于刺激和任务条件，这表明其遗传力较低。然而，γ的遗传力尚未得到评估。在这里，我们表明人类视觉诱导的γ波段同步性具有很强的遗传决定作用。80 名双胞胎受试者（20 对同卵双胞胎和 20 对异卵双胞胎）在观看移动正弦光栅时，使用脑磁图记录他们的大脑活动。刺激在所有受试者的视觉皮层传感器中诱导出频谱受限的γ波段活动，个体峰值频率范围从 45 到 85 Hz。γ波段峰值频率在同卵双胞胎之间高度相关（r = 0.88），但在异卵双胞胎之间（r = 0.32）或无关受试者之间不相关（r = 0.02）。这意味着γ波段频率的遗传力为 91%。这种强烈的遗传决定表明与γ相关的认知功能受到密切的遗传控制。
