Sydnor Valerie J, Petrie Daniel, McKeon Shane D, Famalette Alyssa, Foran Will, Calabro Finnegan J, Luna Beatriz
Department of Psychiatry, University of Pittsburgh Medical Center, University of Pittsburgh, Pittsburgh, PA, USA.
The Center for the Neural Basis of Cognition, University of Pittsburgh and Carnegie Mellon University, Pittsburgh, PA, USA.
bioRxiv. 2025 Jan 30:2025.01.30.635751. doi: 10.1101/2025.01.30.635751.
The human prefrontal cortex (PFC) exhibits markedly protracted developmental plasticity, yet whether reductions in plasticity occur synchronously across prefrontal cortical layers is unclear. Animal studies have shown that intracortical myelin consolidates neural circuits to close periods of plasticity. Here, we use quantitative myelin imaging collected from youth (ages 10-32 years) at ultra-high field (7T) to investigate whether deep and superficial PFC layers exhibit different timeframes of plasticity. We find that myelin matures along a deep-to-superficial axis in the PFC; this axis of maturational timing is expressed to a different extent in cytoarchitecturally distinct regions along the frontal cortical hierarchy. By integrating myelin mapping with electroencephalogram and cognitive phenotyping, we provide evidence that deep and superficial prefrontal myelin dissociably impact timescales of neural activity, task learning rates, and cognitive processing speed. Heterochronous maturation across deep and superficial layers is an underrecognized mechanism through which association cortex balances cognitively-relevant increases in circuit stability and efficiency with extended neuroplasticity.
人类前额叶皮层（PFC）表现出明显延长的发育可塑性，但尚不清楚可塑性的降低是否在前额叶皮层各层同步发生。动物研究表明，皮层内髓鞘形成会巩固神经回路，从而缩短可塑性时期。在此，我们使用从10至32岁的青少年在超高场强（7T）下收集的定量髓鞘成像，来研究前额叶皮层深层和浅层是否表现出不同的可塑性时间框架。我们发现，髓鞘在PFC中沿从深到浅的轴成熟；这种成熟时间轴在额叶皮层层次结构中细胞结构不同的区域中表现程度不同。通过将髓鞘图谱与脑电图和认知表型分析相结合，我们提供证据表明，前额叶深层和浅层髓鞘对神经活动的时间尺度、任务学习率和认知处理速度有不同的影响。深层和浅层之间的异时成熟是一种未被充分认识的机制，通过这种机制，联合皮层在认知相关的回路稳定性和效率增加与延长的神经可塑性之间取得平衡。
