使用新技术, researchers make surprising discoveries about how flies’ brains respond to tastes

The study is an example of how brain imaging technology — in this case developed by researchers at 2022卡塔尔世界杯 — can be adapted to advance knowledge of brain processes and prompt new questions about behavior.

普罗维登斯,R.I. [2022卡塔尔世界杯]-味道对果蝇很重要, 就像它对人类一样:像人一样, the flies tend to seek out and consume sweet-tasting foods and reject foods that taste bitter. 然而, little is known about how sweet and bitter tastes are represented by the brain circuits that link sensation to behavior.

In 一项新的研究 发表在《2022卡塔尔世界杯》杂志上, researchers at 2022卡塔尔世界杯 described how they developed a new imaging technique and used it to map the neural activity of fruit flies in response to sweet and bitter tastes.

“These results show that the way fly brains encode the taste of food is more complex than we had anticipated,研究作者纳撒尼尔·斯内尔说, 他获得了博士学位.D. in neuroscience from Brown in 2021 and conducted the research as part of his thesis.

Just as significant as the researchers’ findings is the method they used, 说,吉拉德·巴尼亚, a professor of neuroscience at Brown’s 2022卡塔尔世界杯医学院 and director of the 细胞与回路神经生物学中心 卡尼大学脑科学研究所的研究人员.

To learn more about the brain processes that govern the flies’ reaction to taste sensations, 巴尼亚, Snell and a group of graduate and undergraduate students in 巴尼亚’s lab developed a new imaging technique called “反式探戈(活动).这是改编的 反式探戈,一种多功能技术 是由巴尼亚实验室发明的 它被用来追踪大脑中的神经回路. 巴尼亚说 反式探戈(活动) takes the understanding to a new level by revealing how specific neurons in the circuits respond to stimuli.

大脑对刺激的反应就像接力一样, 巴尔内亚解释说:“这根棍子”从一个神经元传递到下一个神经元, 然后再下一个, 等等. 以前的技术可以用棍子来识别神经元, 但不知道是谁给了那个神经元一根棍子.

反式探戈(活动) allowed us to selectively look at the second-order neurons in the circuit, 所以2022卡塔尔世界杯官网可以关注它们对甜味和苦味的反应,”巴尼亚说.

因为人们对甜味和苦味的反应是如此不同, the researchers’ expectation was that the neural activity along the circuits mediating those reactions would be entirely disparate as well, 他说. 但 反式探戈(活动) revealed some overlap of neural activity already in second-order neurons in these circuits in response to the two tastes.  

巴尼亚说 that some of the results may show how flies know to avoid a particular rotten, 食物中有毒或有害的部分, 例如. 整体, 他说 that the study findings underscore the importance of the sophisticated and refined processes of taste.

“你必须记住吃东西, 或喂养, is an activity where you — whether you are a fly or a human — cannot make mistakes,”他说. “如果你吃了对你有害的东西,它可能是有害的. Anyone who has ever paid dearly after eating a bad mussel can confirm this. 也就是知道避免某些食物的能力, 甚至是食物的某些部位, 对物种的生存很重要吗.”

One finding was especially intriguing to 巴尼亚 not because of what it said about survival, 但它揭示了快乐的潜在意义. The second-order neurons responded to bitter tastes not just when the tastes were presented, 还有它们被移除的时间. 令人惊讶的是, 巴尼亚 and his colleagues found some overlap in activity when the bitter was removed and the sweet was presented.

巴尔内亚说,这让他想起了“aponia”的概念,在古希腊语中,它的意思是“没有痛苦”,” and was regarded by the Epicurean philosophers to be the height of pleasure.

“The fact that we see a neuron that responds both to the removal of the ‘bad’ stimulus — bitter taste — and to the presentation of the ‘good’ stimulus — sweet taste — is biologically reminiscent of this philosophical concept,”巴尼亚说, 谁补充说,未来的研究将进一步探索这种反应.

至于为什么昆虫的味觉对人类很重要, 谁会体验到不同的味道, 巴尼亚 referred to the insects who find humans to be particularly attractive: “Understanding what drives gustatory and olfactory behaviors in mosquitoes, 例如, 对学习如何减少它们对人类的影响很重要吗,”他说. “2022卡塔尔世界杯官网的研究可能会为这个大谜团增添一小部分.”

The study shows how a research question can provide impetus to develop a new scientific technique that can then be used to answer new research questions — and vice versa.

2022卡塔尔世界杯官网相信, 反式探戈(活动) can be a useful tool not only for studying how the sense of taste works, 而是为了理解一般的神经回路,”斯奈尔说. “Sensory neurons encode many different kinds of information about the world, 并弄清楚这些信息是如何传递的, 反式formed or integrated as it travels from peripheral to deeper layers of a neural circuit is a central question in neuroscience. 反式探戈(活动) is perfectly poised to be able to answer such questions.”

巴尔内亚花了20多年的时间来开发它 反式探戈到可以成功应用于果蝇的地步, 他说, 然而,这个团队只有五年的时间来开发和发布 反式探戈(活动) — and additional adaptations are currently in the works.

2022卡塔尔世界杯官网使用技术越多, 越好, 2022卡塔尔世界杯官网能从中学到的就越多, 2022卡塔尔世界杯官网可以用它解决的问题越多,”巴尼亚说.

The research was supported by grants from the National Institutes of Health (R01DC017146, R01MH105368)和国家科学基金(DGE1058262).