Tracking the evolution of crossmodal plasticity and visual functions before and after sight restoration
Tracking the evolution of crossmodal plasticity and visual functions before and after sight restoration
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DOI：
10.1152/jn.00420.2014
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发表时间：
2015-03-15
影响因子：
2.5
通讯作者：
Collignon, Olivier
中科院分区：
文献类型：
--
作者：
Dormal, Giulia;Lepore, Franco;Collignon, Olivier
视觉剥夺会导致枕叶皮质的结构和功能发生大规模重组，从而给视力恢复带来重大挑战。我们通过磁共振成像追踪了早期严重视力受损患者在视力恢复前以及视力恢复后 1.5 个月和 7 个月内发生的行为、结构和神经功能变化。尽管术前有残余视力，但枕叶皮层仍发现强烈的术前听觉反应。在初级视觉皮层中，跨模式听觉反应与视觉反应重叠，甚至在手术后 7 个月仍保持升高。然而，手术后枕叶区的这些跨模式反应减少，同时行为视力得到改善，低水平视觉区域的灰质密度和神经激活也增加。参与运动和面部处理的高级视觉区域的选择性反应甚至在手术前就可以观察到，并且在手术后不会发生变化。总而言之，这些发现表明，长期患有严重视力障碍的个体存在枕骨区域的结构和功能重组，并且这种重组可以通过成年后的视力恢复来部分逆转。
Visual deprivation leads to massive reorganization in both the structure and function of the occipital cortex, raising crucial challenges for sight restoration. We tracked the behavioral, structural, and neurofunctional changes occurring in an early and severely visually impaired patient before and 1.5 and 7 mo after sight restoration with magnetic resonance imaging. Robust presurgical auditory responses were found in occipital cortex despite residual preoperative vision. In primary visual cortex, crossmodal auditory responses overlapped with visual responses and remained elevated even 7 mo after surgery. However, these crossmodal responses decreased in extrastriate occipital regions after surgery, together with improved behavioral vision and with increases in both gray matter density and neural activation in low-level visual regions. Selective responses in high-level visual regions involved in motion and face processing were observable even before surgery and did not evolve after surgery. Taken together, these findings demonstrate that structural and functional reorganization of occipital regions are present in an individual with a long-standing history of severe visual impairment and that such reorganizations can be partially reversed by visual restoration in adulthood.