Unilateral Vestibular Neurectomy (UVN) induces a postural syndrome whose compensation over time is underpinned by multimodal sensory substitution processes. However, at a chronic stage of compensation, UVN rats exhibit an enduring postural asymmetry expressed by an increase in the body weight on the ipsilesional paws. Given the anatomo-functional links between the vestibular nuclei and the primary somatosensory cortex (S1), we explored the interplay of vestibular and somatosensory cortical inputs following acute and chronic UVN. We determined whether the enduring imbalance in tactilo-plantar inputs impacts response properties of S1 cortical neurons and organizational features of somatotopic maps. We performed electrophysiological mapping of the hindpaw cutaneous representations in S1, immediately and one month after UVN. In parallel, we assessed the posturo-locomotor imbalance during the compensation process. UVN immediately induces an expansion of the cortical neuron cutaneous receptive fields (RFs) leading to a partial dedifferentiation of somatotopic maps. This effect was demonstrated for the ventral skin surface representations and was greater on the contralesional hindpaw for which the neuronal threshold to skin pressure strongly decreased. The RF enlargement was amplified for the representation of the ipsilesional hindpaw in relation to persistent postural asymmetries, but was transitory for the contralesional one. Our study shows, for the first time, that vestibular inputs exert a modulatory influence on S1 neuron’s cutaneous responses. The lesion-induced cortical malleability highlights the influence of vestibular inputs on tactile processing related to postural control.

单侧前庭神经切除术 (UVN) 会诱发一种姿势综合征，其随着时间的推移而得到补偿，这种症状是由多模式感觉替代过程所支撑的。然而，在补偿的慢性阶段，UVN 大鼠表现出持久的姿势不对称，表现为同侧爪上体重的增加。鉴于前庭核和初级体感皮层 (S1) 之间的解剖功能联系，我们探索了急性和慢性 UVN 后前庭和体感皮层输入的相互作用。我们确定了触觉足底输入的持久不平衡是否会影响 S1 皮质神经元的反应特性和体细胞图的组织特征。我们在 UVN 后立即和一个月后对 S1 中的后爪皮肤表现进行了电生理映射。在平行下，我们评估了补偿过程中的姿势运动失衡。UVN 立即引起皮层神经元皮肤感受野 (RF) 的扩张，导致体细胞图的部分去分化。这种效应在腹侧皮肤表面表现中得到证实，并且在对侧后爪上更大，其对皮肤压力的神经元阈值强烈降低。RF 放大被放大以表示与持续姿势不对称相关的同侧后爪，但对于对侧后爪来说是暂时的。我们的研究首次表明，前庭输入对 S1 神经元的皮肤反应具有调节作用。