Department of Neurology, Helsinki University Hospital, and Department of Clinical Neurosciences, University of Helsinki, 00029 Helsinki, Finland
BioMag Laboratory, HUS Medical Imaging Center, Helsinki University Hospital, 00290 Helsinki, Finland.
J Neurosci. 2024 Jan 31;44(5):e0265232023. doi: 10.1523/JNEUROSCI.0265-23.2023.
Individuals' phenotypes, including the brain's structure and function, are largely determined by genes and their interplay. The resting brain generates salient rhythmic patterns that can be characterized noninvasively using functional neuroimaging such as magnetoencephalography (MEG). One of these rhythms, the somatomotor (rolandic) beta rhythm, shows intermittent high amplitude "events" that predict behavior across tasks and species. Beta rhythm is altered in neurological disease. The aperiodic (1/f) signal present in electrophysiological recordings is also modulated by some neurological conditions and aging. Both sensorimotor beta and aperiodic signal could thus serve as biomarkers of sensorimotor function. Knowledge about the extent to which these brain functional measures are heritable could shed light on the mechanisms underlying their generation. We investigated the heritability and variability of human spontaneous sensorimotor beta rhythm events and aperiodic activity in 210 healthy male and female adult siblings' spontaneous MEG activity. The most heritable trait was the aperiodic 1/f signal, with a heritability of 0.87 in the right hemisphere. Time-resolved beta event amplitude parameters were also highly heritable, whereas the heritabilities for overall beta power, peak frequency, and measures of event duration remained nonsignificant. Human sensorimotor neural activity can thus be dissected into different components with variable heritability. We postulate that these differences partially reflect different underlying signal-generating mechanisms. The 1/f signal and beta event amplitude measures may depend more on fixed, anatomical parameters, whereas beta event duration and its modulation reflect dynamic characteristics, guiding their use as potential disease biomarkers.
个体的表型，包括大脑的结构和功能，在很大程度上是由基因及其相互作用决定的。静息状态下的大脑会产生显著的节律模式，可以使用脑磁图（MEG）等功能神经影像学技术进行无创性特征描述。其中一种节律是躯体运动（罗兰多）β节律，它表现出间歇性的高振幅“事件”，可以预测不同任务和物种的行为。β节律在神经疾病中发生改变。在电生理记录中存在的非周期性（1/f）信号也会受到一些神经状况和衰老的调制。因此，躯体感觉β节律和非周期性信号都可以作为躯体感觉功能的生物标志物。了解这些大脑功能测量的遗传性程度可以揭示其产生的机制。我们在 210 名健康男性和女性成年兄弟姐妹的自发 MEG 活动中，研究了人类自发性躯体感觉β节律事件和非周期性活动的遗传性和可变性。最具遗传性的特征是无周期性 1/f 信号，右半球的遗传性为 0.87。时间分辨β事件幅度参数也具有高度遗传性，而总体β功率、峰值频率和事件持续时间的遗传性仍不显著。因此，人类躯体感觉神经活动可以分解为具有不同遗传性的不同成分。我们假设这些差异部分反映了不同的潜在信号产生机制。1/f 信号和β事件幅度测量值可能更多地依赖于固定的解剖参数，而β事件持续时间及其调制反映了动态特征，指导它们作为潜在疾病生物标志物的使用。
