PDF(Pubmed)
Abstract：
Visual object memory is a fundamental element of various cognitive abilities, and the underlying neural mechanisms have been extensively examined especially in the anterior temporal cortex of primates. However, both macroscopic large-scale functional network in which this region is embedded and microscopic neuron-level dynamics of top-down regulation it receives for object memory remains elusive. Here, we identified the orbitofrontal node as a critical partner of the anterior temporal node for object memory by combining whole-brain functional imaging during rest and a short-term object memory task in male macaques. Focal chemogenetic silencing of the identified orbitofrontal node downregulated both the local orbitofrontal and remote anterior temporal nodes during the task, in association with deteriorated mnemonic, but not perceptual, performance. Furthermore, imaging-guided neuronal recordings in the same monkeys during the same task causally revealed that orbitofrontal top-down modulation enhanced stimulus-selective mnemonic signal in individual anterior temporal neurons while leaving bottom-up perceptual signal unchanged. Furthermore, similar activity difference was also observed between correct and mnemonic error trials before silencing, suggesting its behavioral relevance. These multifaceted but convergent results provide a multiscale causal understanding of dynamic top-down regulation of the anterior temporal cortex along the ventral fronto-temporal network underpinning short-term object memory in primates.
摘要：
视觉对象记忆是各种认知能力的基本要素,和潜在的神经机制已经被广泛研究，特别是在灵长类动物的前颞叶皮层。然而,嵌入该区域的宏观大规模功能网络和它为对象记忆接收的自上而下调节的微观神经元水平动力学仍然难以捉摸。这里,我们通过结合休息期间的全脑功能成像和雄性猕猴的短期对象记忆任务,将眶额叶节点确定为对象记忆的前颞节点的关键伙伴.在任务过程中，已识别的眶额节点的局灶性化学遗传沉默使局部眶额节点和远端前颞叶节点均下调，与恶化的助记符相关联，但不是感性的，性能。此外，在同一任务期间，在同一只猴子中进行的成像引导的神经元记录因果关系表明，眶额自上而下的调制增强了单个前颞神经元中的刺激选择性记忆信号，而自下而上的感知信号保持不变。此外，在沉默前的正确和记忆错误试验之间也观察到类似的活动差异，表明了它的行为相关性。这些多方面但趋同的结果提供了多尺度的因果理解，即前颞叶皮层沿腹侧额-颞叶网络的动态自上而下调节，从而支撑了灵长类动物的短期物体记忆。
