小柯机器人

英国牛津大学Scott Waddell等研究人员合作发现，多感官学习将神经元结合成一个跨模式的记忆印记。这一研究成果于2023年4月26日在线发表在国际学术期刊《自然》上。

研究人员在果蝇中展示了多感官的食欲和厌恶性记忆。将颜色和气味结合起来可以提高记忆表现，即使每种感觉方式都单独测试。对神经元功能的时间控制显示，视觉选择性的蘑菇体Kenyon细胞（KC）在多感官训练后对视觉和嗅觉记忆的增强是必需的。头部固定果蝇的电压成像显示，多感官学习在特定模式的KC流之间结合活动，从而使单模式的感觉输入产生多模式的神经元反应。结合发生在嗅觉和视觉KC轴突的区域之间，这些轴突接受价值相关的多巴胺能强化，并向下游传播。

多巴胺局部释放GABA能抑制，允许跨越KC的5-羟色胺能神经元内的特定微循环作为以前“模式选择性”KC流之间的兴奋性桥梁发挥作用。跨模态结合从而使代表每种模态的记忆程序的KC扩展到代表另一种模态的KC。记忆图谱的这种扩大改善了多感官学习后的记忆表现，并允许用单一的感官特征来检索多模态经验的记忆。

据介绍，将多种感觉线索与物体和经验联系起来是一个基本的大脑过程，可以提高物体识别和记忆的表现。然而，在学习过程中结合感觉特征并增强记忆表达的神经机制尚不清楚。

附：英文原文

Title: Multisensory learning binds neurons into a cross-modal memory engram

Author: Okray, Zeynep, Jacob, Pedro F., Stern, Ciara, Desmond, Kieran, Otto, Nils, Talbot, Clifford B., Vargas-Gutierrez, Paola, Waddell, Scott

Issue&Volume: 2023-04-26

Abstract: Associating multiple sensory cues with objects and experience is a fundamental brain process that improves object recognition and memory performance. However, neural mechanisms that bind sensory features during learning and augment memory expression are unknown. Here we demonstrate multisensory appetitive and aversive memory in Drosophila. Combining colours and odours improved memory performance, even when each sensory modality was tested alone. Temporal control of neuronal function revealed visually selective mushroom body Kenyon cells (KCs) to be required for enhancement of both visual and olfactory memory after multisensory training. Voltage imaging in head-fixed flies showed that multisensory learning binds activity between streams of modality-specific KCs so that unimodal sensory input generates a multimodal neuronal response. Binding occurs between regions of the olfactory and visual KC axons, which receive valence-relevant dopaminergic reinforcement, and is propagated downstream. Dopamine locally releases GABAergic inhibition to permit specific microcircuits within KC-spanning serotonergic neurons to function as an excitatory bridge between the previously ‘modality-selective’ KC streams. Cross-modal binding thereby expands the KCs representing the memory engram for each modality into those representing the other. This broadening of the engram improves memory performance after multisensory learning and permits a single sensory feature to retrieve the memory of the multimodal experience.

DOI: 10.1038/s41586-023-06013-8

Source: https://www.nature.com/articles/s41586-023-06013-8

Nature：《自然》，创刊于1869年。隶属于施普林格·自然出版集团，最新IF：69.504
官方网址：http://www.nature.com/
投稿链接：http://www.nature.com/authors/submit_manuscript.html