果蠅穩定航向生成原因
作者:
小柯機器人發布時間:2019/11/21 14:19:00
美國霍華德休斯醫學研究所Vivek Jayaraman和Sung Soo Kim研究組發現,果蠅在不同的視覺場景中生成穩定的航向表示形式。該項研究成果11月20日在線發表在《自然》上。
研究人員將拴系蠅中的雙光子鈣成像和光遺傳學與電路建模相結合,並表明羅盤和視覺神經元的相關活動如何驅動可塑性,從而靈活地轉換二維視覺線索,將其變成穩定的導航表示形式。他們還描述了這種可塑性如何使果蠅將部分方位表示形式(從在新環境的一部分中的定位確定)轉換為完整的導航表示形式。他們的結果提供了對與記憶相關的計算的機械洞察力,這對於在各種環境中進行靈活導航至關重要。
據了解,不同的環境中導航時,許多動物都依賴內部導航表示。目前尚不清楚該表示如何與定義不同環境的感覺線索相關聯。在果蠅大腦中,航向由「羅盤」神經元代表,這些神經元支配著一個稱為橢球體的環形結構。每個羅盤神經元接收來自「環形」神經元的輸入,這些輸入對於特定的視覺特徵具有選擇性;這種結合為從視覺場景中提取方向信息提供了理想的基礎。
附:英文原文
Title: Generation of stable heading representations in diverse visual scenes
Author: Sung Soo Kim, Ann M. Hermundstad, Sandro Romani, L. F. Abbott & Vivek Jayaraman
Issue&Volume: 2019-11-20
Abstract: Many animals rely on an internal heading representation when navigating in varied environments. How this representation is linked to the sensory cues that define different surroundings is unclear. In the fly brain, heading is represented by compass neurons that innervate a ring-shaped structure known as the ellipsoid body. Each compass neuron receives inputs from ring neurons that are selective for particular visual features; this combination provides an ideal substrate for the extraction of directional information from a visual scene. Here we combine two-photon calcium imaging and optogenetics in tethered flying flies with circuit modelling, and show how the correlated activity of compass and visual neurons drives plasticity, which flexibly transforms two-dimensional visual cues into a stable heading representation. We also describe how this plasticity enables the fly to convert a partial heading representation, established from orienting within part of a novel setting, into a complete heading representation. Our results provide mechanistic insight into the memory-related computations that are essential for flexible navigation in varied surroundings. Two-photon calcium imaging and optogenetic experiments in tethered flying flies, combined with modelling, demonstrate how the correlation of compass and visual neurons underpins plasticity that enables the transformation of visual cues into stable heading representations.
DOI: 10.1038/s41586-019-1767-1
Source:https://www.nature.com/articles/s41586-019-1767-1