Unravelling the mechanisms for attention-like behaviour in the central brain of Drosophila melanogaster

选择性注意是一种认知过程，通过关注相关刺激的子集，同时忽略不重要的感官影响，使动物能够与周围环境进行适应性互动（Posner et al. 1980）。因此，对于所有物种来说，在大脑中创造一个它们周围环境的工作表征，并在这个表征中放置它们的位置，是一个至关重要的过程。因此，选择性注意可能对导航、决策、学习和记忆都很重要。大多数动物似乎表现出选择性注意的能力，尽管动物物种在行为特征和神经解剖学上与人类有很大不同。这就提出了一个问题：选择性注意是否存在于所有大脑的基本机制之下，尽管它们在神经解剖学上存在差异？此外，选择性注意是否反映了大脑中与其他认知过程（如导航、决策或学习）相互作用的保守的增益控制机制？在我的实验中，我将把重点放在最小的大脑上，在果蝇（Van Swinderen and Greenspan 2003）中，选择性注意力已经被确定，并试图理解它是如何工作的。黑胃果蝇是研究大脑基本机制的一个很有前途的模型。中央复核（CC）是昆虫大脑中央的一个区域，在控制高阶行为方面的作用越来越大（Ofstad et al. 2011, Liu et al. 2006）。这些高阶过程正越来越多地在果蝇CC的回路水平上进行研究，以解开认知行为背后的机制。在我的提案中，我的目标是回答以下问题：注意力样过程（通过内源性或外源性振荡神经元活动的增益控制来测量）存在于果蝇的CC中吗？什么结构有助于产生与选择性注意相关的神经元活动，例如特定频率的振荡？反馈回路如何产生选择性注意的机制？这种机制是如何与其他认知功能（如学习）相互作用或影响的？为了回答这些问题，我将运用我最近优化的新范式来研究果蝇的注意力神经元机制。这些范式结合了人类注意力研究中常见的复杂方法，如频率标记（Norcia et al. 2015），苍蝇脑电生理学和光遗传学的新方法，以及一种新的虚拟现实范式，允许在历史背景下研究注意力。这些方法的结合将使我们更好地理解选择性注意的基本方面，以及它是如何塑造复杂行为的。

Selective attention is a cognitive process, allowing animals to interact adaptively with their surroundings, by focusing on a subset of relevant stimuli while ignoring unimportant sensory influences at the same time (Posner et al. 1980). It is therefore a crucial process for all species to create a working representation of their surrounding in the brain, and for placing their position within this representation. As such, selective attention is likely to be important for navigation, decision-making, and for learning and memory. Most animals appear to display a capacity for selective attention, although animal species differ considerably from humans in their behavioural repertoires and neuroanatomy. This raises the question of whether selective attention underlies fundamental mechanisms that are present in all brains, despite their differences in neuroanatomy? Also, does selective attention reflect conserved gain-control mechanisms in the brain that interact with other cognitive processes, such as navigation, decision making, or learning? In my experiments, I will focus on the smallest brain where selective-attention has been identified, in the fruit fly (Van Swinderen and Greenspan 2003), and try to understand how it works. Drosophila melanosgaster is a promising model for studying fundamental brain mechanisms. The central complex (CC), a region in the central brain of insects, has been increasingly implicated in the control of higher-order behaviours (Ofstad et al. 2011, Liu et al. 2006). These higher-order processes are being increasingly studied at the circuit level in the CC of fruit flies, in order to disentangle mechanisms underlying cognitive behaviour. In my proposal I aim to answer the following questions: Are attention-like processes (measured by gain-control of endogenous or exogenous oscillatory neuronal activity) present in the CC of fruit flies? What structures contribute to the generation of neuronal activity associated with selective attention, such as frequency-specific oscillations? How does feedback circuitry give rise to mechanisms of selective attention? How does this mechanism interact with or influence other cognitive functions, such as learning? To answer these questions, I will apply new paradigms that I have recently optimized to study neuronal mechanisms of attention in the fruit fly. These paradigms combine sophisticated methods common in human attention research, such as frequency tagging (Norcia et al. 2015), new approaches in fly brain electrophysiology and optogenetics, and a new virtual reality paradigm allowing attention to be studied in a historical context. The combination of these methods will lead to a better understanding of fundamental aspects of selective attention, and how it operates to shape complex behaviour.