Broday-Dvir Rotem, Malach Rafael
Department of Neurobiology, Weizmann Institute of Science, Rehovot 76100, Israel.
Cereb Cortex. 2021 Jan 1;31(1):213-232. doi: 10.1093/cercor/bhaa221.
Resting-state fluctuations are ubiquitous and widely studied phenomena of the human brain, yet we are largely in the dark regarding their function in human cognition. Here we examined the hypothesis that resting-state fluctuations underlie the generation of free and creative human behaviors. In our experiment, participants were asked to perform three voluntary verbal tasks: a verbal fluency task, a verbal creativity task, and a divergent thinking task, during functional magnetic resonance imaging scanning. Blood oxygenation level dependent (BOLD)-activity during these tasks was contrasted with a control- deterministic verbal task, in which the behavior was fully determined by external stimuli. Our results reveal that all voluntary verbal-generation responses displayed a gradual anticipatory buildup that preceded the deterministic control-related responses. Critically, the time-frequency dynamics of these anticipatory buildups were significantly correlated with resting-state fluctuations' dynamics. These correlations were not a general BOLD-related or verbal-response related result, as they were not found during the externally determined verbal control condition. Furthermore, they were located in brain regions known to be involved in language production, specifically the left inferior frontal gyrus. These results suggest a common function of resting-state fluctuations as the neural mechanism underlying the generation of free and creative behaviors in the human cortex.
静息态波动是人类大脑中普遍存在且被广泛研究的现象，但我们对其在人类认知中的功能仍知之甚少。在此，我们检验了这样一种假设：静息态波动是人类自由和创造性行为产生的基础。在我们的实验中，参与者在功能磁共振成像扫描期间被要求执行三项自愿性言语任务：言语流畅性任务、言语创造性任务和发散性思维任务。这些任务期间的血氧水平依赖（BOLD）活动与一项对照性确定性言语任务进行了对比，在该对照任务中，行为完全由外部刺激决定。我们的结果显示，所有自愿性言语生成反应均表现出一种逐渐的预期增强，这种增强先于与确定性对照相关的反应。关键的是，这些预期增强的时频动态与静息态波动的动态显著相关。这些相关性并非一般的与BOLD相关或与言语反应相关的结果，因为在外部决定的言语控制条件下未发现这种相关性。此外，它们位于已知参与语言产生的脑区，特别是左侧额下回。这些结果表明，静息态波动具有一种共同功能，作为人类皮层中自由和创造性行为产生的神经机制。
