Baena Daniel, Fang Zhuo, Ray Laura B, Owen Adrian M, Fogel Stuart M
Sleep Unit, University of Ottawa Institute of Mental Health Research at The Royal, Ontario K1Z 7K4, Ottawa, Canada.
School of Psychology, University of Ottawa, Ottawa, Ontario K1N 6N5, Canada.
Cereb Cortex. 2023 Apr 25;33(9):5409-5419. doi: 10.1093/cercor/bhac428.
Sleep spindles (SP) are one of the few known electrophysiological neuronal biomarkers of interindividual differences in cognitive abilities and aptitudes. Recent simultaneous electroencephalography with functional magnetic resonance imaging (EEG-fMRI) studies suggest that the magnitude of the activation of brain regions recruited during spontaneous spindle events is specifically related to Reasoning abilities. However, it is not known if the relationship with cognitive abilities differs between uncoupled spindles, uncoupled slow waves (SW), and coupled SW-SP complexes, nor have the functional-neuroanatomical substrates that support this relationship been identified. Here, we investigated the functional significance of activation of brain areas recruited during SW-coupled spindles, uncoupled spindles, and uncoupled slow waves. We hypothesize that brain activations time locked to SW-coupled spindle complexes will be primarily associated to Reasoning abilities, especially in subcortical areas. Our results provide direct evidence that the relationship between Reasoning abilities and sleep spindles depends on spindle coupling status. Specifically, we found that the putamen and thalamus, recruited during coupled SW-SP events were positively correlated with Reasoning abilities. In addition, we found a negative association between Reasoning abilities and hippocampal activation time-locked to uncoupled SWs that might reflect a refractory mechanism in the absence of new, intensive hippocampal-dependent memory processing.
睡眠纺锤波（SP）是少数已知的认知能力和天赋个体差异的电生理神经元生物标志物之一。最近同步进行脑电图与功能磁共振成像（EEG-fMRI）的研究表明，在自发纺锤波事件期间所募集的脑区激活程度与推理能力有特定关联。然而，尚不清楚未耦合的纺锤波、未耦合的慢波（SW）以及耦合的SW-SP复合体与认知能力之间的关系是否存在差异，支持这种关系的功能神经解剖学基础也尚未明确。在此，我们研究了在SW耦合纺锤波、未耦合纺锤波和未耦合慢波期间所募集的脑区激活的功能意义。我们假设与SW耦合纺锤波复合体时间锁定的脑激活主要与推理能力相关，尤其是在皮层下区域。我们的结果提供了直接证据，表明推理能力与睡眠纺锤波之间的关系取决于纺锤波耦合状态。具体而言，我们发现，在耦合的SW-SP事件期间所募集的壳核和丘脑与推理能力呈正相关。此外，我们发现推理能力与与未耦合SW时间锁定的海马体激活之间存在负相关，这可能反映了在缺乏新的、依赖海马体的密集记忆处理时的一种不应机制。
