Laboratory of Experimental Neuroscience LaNCE, Department of Neuroscience, Faculty of Medicine and Odontology, University of the Basque Country (UPV/EHU), Sarriena Auzoa, 48940 Leioa, Spain.
Neural Plast. 2012;2012:305693. doi: 10.1155/2012/305693. Epub 2012 Jul 9.
During postnatal development, sensory experience modulates cortical development, inducing numerous changes in all of the components of the cortex. Most of the cortical changes thus induced occur during the critical period, when the functional and structural properties of cortical neurons are particularly susceptible to alterations. Although the time course for experience-mediated sensory development is specific for each system, postnatal development acts as a whole, and if one cortical area is deprived of its normal sensory inputs during early stages, it will be reorganized by the nondeprived senses in a process of cross-modal plasticity that not only increases performance in the remaining senses when one is deprived, but also rewires the brain allowing the deprived cortex to process inputs from other senses and cortices, maintaining the modular configuration. This paper summarizes our current understanding of sensory systems development, focused specially in the visual system. It delineates sensory enhancement and sensory deprivation effects at both physiological and anatomical levels and describes the use of enriched environment as a tool to rewire loss of brain areas to enhance other active senses. Finally, strategies to apply restorative features in human-deprived senses are studied, discussing the beneficial and detrimental effects of cross-modal plasticity in prostheses and sensory substitution devices implantation.
在出生后的发育过程中,感觉体验会调节皮质发育,引起皮质所有成分的大量变化。因此,大多数诱导的皮质变化发生在关键期,此时皮质神经元的功能和结构特性特别容易发生改变。虽然经验介导的感觉发育的时程对于每个系统都是特定的,但出生后的发育是作为一个整体发生的,如果一个皮质区域在早期阶段被剥夺了正常的感觉输入,那么它将被非剥夺感觉重新组织,这是一种跨模态可塑性的过程,不仅在被剥夺感觉时提高了剩余感觉的性能,而且还重塑了大脑,使被剥夺的皮质能够处理来自其他感觉和皮质的输入,保持模块化配置。本文总结了我们目前对感觉系统发育的理解,特别关注视觉系统。它描述了在生理和解剖水平上的感觉增强和感觉剥夺效应,并描述了使用丰富环境作为一种工具来重新布线大脑区域的丧失,以增强其他活跃的感觉。最后,研究了在人类剥夺感觉中应用恢复特征的策略,讨论了在假体和感觉替代装置植入中跨模态可塑性的有益和有害影响。