Institute of AudioNeuroTechnology and Department of Experimental Otology, Otolaryngology Clinics, Hannover Medical School, Hannover, Germany; Australian Hearing Hub, School of Medicine and Health Sciences, Macquarie University, Sydney, NSW, Australia.
Department of Speech Language and Hearing Science, Center for Neuroscience, Institute of Cognitive Science, University of Colorado Boulder, Boulder, CO, USA.
Trends Neurosci. 2023 May;46(5):377-393. doi: 10.1016/j.tins.2023.02.004. Epub 2023 Mar 27.
Crossmodal plasticity is a textbook example of the ability of the brain to reorganize based on use. We review evidence from the auditory system showing that such reorganization has significant limits, is dependent on pre-existing circuitry and top-down interactions, and that extensive reorganization is often absent. We argue that the evidence does not support the hypothesis that crossmodal reorganization is responsible for closing critical periods in deafness, and crossmodal plasticity instead represents a neuronal process that is dynamically adaptable. We evaluate the evidence for crossmodal changes in both developmental and adult-onset deafness, which start as early as mild-moderate hearing loss and show reversibility when hearing is restored. Finally, crossmodal plasticity does not appear to affect the neuronal preconditions for successful hearing restoration. Given its dynamic and versatile nature, we describe how this plasticity can be exploited for improving clinical outcomes after neurosensory restoration.
跨模态可塑性是大脑根据使用进行重组的典型范例。我们回顾了来自听觉系统的证据，表明这种重组具有显著的局限性，依赖于预先存在的电路和自上而下的相互作用，而且广泛的重组通常不存在。我们认为，这些证据并不支持跨模态重组负责关闭耳聋关键期的假设，而跨模态可塑性代表的是一种动态适应性的神经元过程。我们评估了发育性和成人期耳聋中跨模态变化的证据，这些变化早在轻度到中度听力损失时就开始出现，并在听力恢复时表现出可逆性。最后，跨模态可塑性似乎不会影响成功恢复听力的神经元前提条件。鉴于其动态和多功能的性质，我们描述了如何利用这种可塑性来改善神经感觉恢复后的临床结果。
