The sleep spindle, a waxing and waning oscillation in the sigma frequency range, has been shown to correlate with fluid intelligence; i.e. the ability to use logic, learn novel rules/patterns, and solve problems. Using simultaneous EEG and fMRI, we previously identified the neural correlates of this relationship, including activation of the thalamus, bilateral putamen, medial frontal gyrus, middle cingulate cortex, and precuneus. However, research to date has focussed primarily on non-rapid eye movement (NREM) sleep, and spindles per se, thus overlooking the possibility that brain activity that occurs in other sleep–wake states might also be related to cognitive abilities. In our current study, we sought to investigate whether brain activity across sleep/wake states is also related to human intelligence in N = 29 participants. During NREM sleep, positive correlations were observed between fluid intelligence and blood oxygen level dependent (BOLD) activations in the bilateral putamen and the paracentral lobule/precuneus, as well as between short-term memory (STM) abilities and activity in the medial frontal cortex and inferior frontal gyrus. During wake, activity in bilateral postcentral gyri and occipital lobe was positively correlated with short-term memory abilities. In participants who experienced REM sleep in the scanner, fluid intelligence was positively associated with midbrain activation, and verbal intelligence was associated with right postcentral gyrus activation. These findings provide evidence that the relationship between sleep and intellectual abilities exists beyond sleep spindles.

睡眠纺锤波是 sigma 频率范围内的起伏振荡，已被证明与流体智力相关；即使用逻辑、学习新规则/模式和解决问题的能力。使用同步 EEG 和 fMRI，我们之前确定了这种关系的神经相关性，包括丘脑、双侧壳核、内侧额回、中扣带回和楔前叶的激活。然而，迄今为止的研究主要集中在非快速眼动 (NREM) 睡眠和纺锤体本身，因此忽略了在其他睡眠-觉醒状态下发生的大脑活动也可能与认知能力有关的可能性。在我们目前的研究中，我们试图在 N = 29 名参与者中调查睡眠/清醒状态下的大脑活动是否也与人类智力有关。在 NREM 睡眠期间，流体智力与双侧壳核和中央旁小叶/楔前叶的血氧水平依赖性 (BOLD) 激活之间以及内侧额叶皮层和额下回的短期记忆 (STM) 能力和活动之间观察到正相关. 在清醒期间，双侧中央后回和枕叶的活动与短期记忆能力呈正相关。在扫描仪中经历 REM 睡眠的参与者中，流体智力与中脑激活呈正相关，而语言智力与右侧中央后回激活相关。这些发现提供了证据，证明睡眠和智力之间的关系存在于睡眠纺锤体之外。