Innate behavioral biases and preferences can vary significantly among individuals of the same genotype. Though individuality is a fundamental property of behavior, it is not currently understood how individual differences in brain structure and physiology produce idiosyncratic behaviors. Here we present evidence for idiosyncrasy in olfactory behavior and neural responses in Drosophila. We show that individual female Drosophila from a highly inbred laboratory strain exhibit idiosyncratic odor preferences that persist for days. We used in vivo calcium imaging of neural responses to compare projection neuron (second-order neurons that convey odor information from the sensory periphery to the central brain) responses to the same odors across animals. We found that, while odor responses appear grossly stereotyped, upon closer inspection, many individual differences are apparent across antennal lobe (AL) glomeruli (compact microcircuits corresponding to different odor channels). Moreover, we show that neuromodulation, environmental stress in the form of altered nutrition, and activity of certain AL local interneurons affect the magnitude of interfly behavioral variability. Taken together, this work demonstrates that individual Drosophila exhibit idiosyncratic olfactory preferences and idiosyncratic neural responses to odors, and that behavioral idiosyncrasies are subject to neuromodulation and regulation by neurons in the AL.

在相同基因型的个体之间，先天的行为偏见和偏爱可能有很大的不同。尽管个性是行为的基本属性，但目前尚不了解大脑结构和生理上的个体差异如何产生特质行为。在这里，我们提供果蝇嗅觉行为和神经反应特质的证据。我们证明了个体女性果蝇高度自交系实验室菌株产生的异味气味持续数天。我们使用了神经反应的体内钙成像技术来比较投射神经元（将气味信息从感觉边缘传递到中枢大脑的二阶神经元）对动物中相同气味的反应。我们发现，尽管气味反应大致定型，但仔细检查后，在触角叶（AL）肾小球（紧凑的微电路，对应于不同的气味通道）上会出现许多个体差异。此外，我们表明神经调节，营养改变形式的环境压力以及某些AL局部中间神经元的活动会影响果蝇行为变异的程度。两者合计，这项工作表明果蝇个体 表现出特异的嗅觉偏好和对气味的特异神经反应，并且行为特质受到AL中神经元的神经调节和调节。