Berardi Nicoletta, Sale Alessandro, Maffei Lamberto
Department of Neuroscience, Psychology, Drug Research, Child Health (NEUROFARBA), Florence University, Florence, Italy; Neuroscience Institute, National Research Council (CNR), Pisa, Italy.
Dev Med Child Neurol. 2015 Apr;57 Suppl 2:4-9. doi: 10.1111/dmcn.12691.
Brain development is the result of the combined work of genes and environment. In this paper we first briefly discuss how, in terms of cellular and molecular plasticity mechanisms, the richness of early environment can control developmental trajectories and can induce long-term changes in neural circuits that underlie enduring changes in brain structure and function. We then see that experience most effectively moulds neural circuit development during specific time windows called critical periods. After the closure of these privileged windows for plasticity, it is very difficult to promote repair from 'errors' in brain development. As an example, congenital cataracts, refractive defects, or strabismus, if not precociously corrected during development, cause permanent deficit in visual acuity of the affected eye, a condition known as amblyopia. Little or no recovery from amblyopia is possible in the adult. However, recent results show that by using protocols of enriched environment it is possible to design interventions, which, by acting on specific plasticity factors, enhance adult cortical plasticity and allow recovery from amblyopia. This suggests that a better knowledge of how experience and environment engage endogenous plasticity factors could help to design interventions aimed at promoting recovery from neurodevelopmental defects, even after the end of critical periods.
大脑发育是基因与环境共同作用的结果。在本文中，我们首先简要讨论，就细胞和分子可塑性机制而言，早期环境的丰富程度如何控制发育轨迹，并能在神经回路中诱导长期变化，而这些变化是大脑结构和功能持久改变的基础。接着我们会看到，在被称为关键期的特定时间窗口内，经验能最有效地塑造神经回路发育。在这些可塑性特权窗口关闭后，很难促进大脑发育“错误”的修复。例如，先天性白内障、屈光缺陷或斜视，如果在发育过程中没有及早矫正，会导致患眼视力永久性下降，即所谓的弱视。成年人弱视几乎无法恢复或恢复程度极小。然而，最近的研究结果表明，通过采用丰富环境方案，可以设计出一些干预措施，这些措施通过作用于特定的可塑性因子，增强成年皮质可塑性，并使弱视得以恢复。这表明，更深入了解经验和环境如何激活内源性可塑性因子，有助于设计旨在促进神经发育缺陷恢复的干预措施，即使在关键期结束后也是如此。
