Institute for research in Psychology (IPSY) & Neuroscience (IoNS), Louvain Bionics, Crossmodal Perception and Plasticity Laboratory - University of Louvain (UCLouvain), Louvain-la-Neuve, Belgium.
Department of Brain and Cognition, KU Leuven, Leuven, Belgium.
Elife. 2022 Sep 7;11:e79370. doi: 10.7554/eLife.79370.
The ventral occipito-temporal cortex (VOTC) reliably encodes auditory categories in people born blind using a representational structure partially similar to the one found in vision (Mattioni et al.,2020). Here, using a combination of uni- and multivoxel analyses applied to fMRI data, we extend our previous findings, comprehensively investigating how early and late acquired blindness impact on the cortical regions coding for the deprived and the remaining senses. First, we show enhanced univariate response to sounds in part of the occipital cortex of both blind groups that is concomitant to reduced auditory responses in temporal regions. We then reveal that the representation of the sound categories in the occipital and temporal regions is more similar in blind subjects compared to sighted subjects. What could drive this enhanced similarity? The multivoxel encoding of the 'human voice' category that we observed in the temporal cortex of all sighted and blind groups is enhanced in occipital regions in blind groups , suggesting that the representation of vocal information is more similar between the occipital and temporal regions in blind compared to sighted individuals. We additionally show that blindness does not affect the encoding of the acoustic properties of our sounds (e.g. pitch, harmonicity) in occipital and in temporal regions but instead selectively alter the categorical coding of the voice category itself. These results suggest a functionally congruent interplay between the reorganization of occipital and temporal regions following visual deprivation, across the lifespan.
腹侧枕颞皮质（VOTC）在先天盲人群中可靠地编码听觉类别，其代表性结构与视觉中发现的部分相似（Mattioni 等人，2020）。在这里，我们使用单变量和多变量分析相结合的方法对 fMRI 数据进行分析，扩展了我们之前的发现，全面研究了早期和晚期失明如何影响编码剥夺和剩余感觉的皮质区域。首先，我们发现在两个盲人群体的部分枕叶皮质中，对声音的单变量反应增强，同时颞区的听觉反应减弱。然后我们揭示了在盲人和视力正常的人群中，声音类别的代表在枕叶和颞叶区域更为相似。是什么导致了这种增强的相似性？我们在所有视力正常和盲人群体的颞叶皮质中观察到的“人声”类别的多变量编码在盲人群体的枕叶区域中增强，这表明在盲人群体中，与视觉正常的个体相比，声音信息的表示在枕叶和颞叶区域之间更为相似。我们还表明，失明不会影响声音的声学特性（例如音高、谐波性）在枕叶和颞叶区域的编码，而是选择性地改变声音类别本身的分类编码。这些结果表明，在整个生命周期中，视觉剥夺后枕叶和颞叶区域之间存在功能上一致的相互作用。
