Key Laboratory of Brain Functional Genomics (Ministry of Education), East China Normal University, Shanghai, China.
Gonda Multidisciplinary Brain Research Center, Bar-Ilan University, Ramat Gan, Israel.
Elife. 2023 Mar 6;12:e82895. doi: 10.7554/eLife.82895.
The adult brain demonstrates remarkable multisensory plasticity by dynamically recalibrating itself based on information from multiple sensory sources. After a systematic visual-vestibular heading offset is experienced, the unisensory perceptual estimates for subsequently presented stimuli are shifted toward each other (in opposite directions) to reduce the conflict. The neural substrate of this recalibration is unknown. Here, we recorded single-neuron activity from the dorsal medial superior temporal (MSTd), parietoinsular vestibular cortex (PIVC), and ventral intraparietal (VIP) areas in three male rhesus macaques during this visual-vestibular recalibration. Both visual and vestibular neuronal tuning curves in MSTd shifted - each according to their respective cues' perceptual shifts. Tuning of vestibular neurons in PIVC also shifted in the same direction as vestibular perceptual shifts (cells were not robustly tuned to the visual stimuli). By contrast, VIP neurons demonstrated a unique phenomenon: both vestibular and visual tuning shifted in accordance with vestibular perceptual shifts. Such that, visual tuning shifted, surprisingly, contrary to visual perceptual shifts. Therefore, while unsupervised recalibration (to reduce cue conflict) occurs in early multisensory cortices, higher-level VIP reflects only a global shift, in vestibular space.
成人大脑具有显著的多感觉可塑性，能够根据来自多个感觉源的信息动态地重新校准自身。在系统性地经历视觉-前庭头部偏移后，随后呈现的刺激的单一感觉估计会相互（向相反方向）移动，以减少冲突。这种重新校准的神经基础尚不清楚。在这里，我们在三只雄性恒河猴的背内侧上颞（MSTd）、顶-岛叶前庭皮质（PIVC）和腹内顶（VIP）区域记录了单个神经元的活动，在此期间进行了视觉-前庭重新校准。MSTd 中的视觉和前庭神经元调谐曲线都发生了 - 每个曲线根据其各自线索的感知变化而变化。PIVC 中的前庭神经元调谐也朝着与前庭感知变化相同的方向发生变化（细胞对视觉刺激的调谐不明显）。相比之下，VIP 神经元表现出一种独特的现象：前庭和视觉调谐都根据前庭感知变化而变化。因此，尽管在早期多感觉皮层中发生了无监督的重新校准（以减少线索冲突），但 VIP 等高级区域仅反映了前庭空间中的全局变化。
