Effects of stochastic coding on olfactory discrimination in flies and mice.
Effects of stochastic coding on olfactory discrimination in flies and mice.
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DOI：
10.1371/journal.pbio.3002206
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发表时间：
2023-10
期刊：
影响因子：
9.8
通讯作者：
Navlakha, Saket
中科院分区：
文献类型：
--
作者：
Srinivasan, Shyam;Daste, Simon;Modi, Mehrab N.;Turner, Glenn C.;Fleischmann, Alexander;Navlakha, Saket
稀疏编码可以通过减少感官刺激表征之间的重叠来提高对感官刺激的辨别能力。然而，有两个因素可以抵消稀疏编码的好处：相似的感官刺激有显著的重叠，不同试验的反应不同。为了阐明这两个因素的影响，我们分析了果蝇和小鼠的嗅觉区域——蘑菇体（MB）和梨状皮质（PCx）的气味反应，这些嗅觉区域与学习和区分有关。我们发现神经元反应沿着一个连续体下降，从非常可靠的试验到极端可变或随机。通过计算，我们证明了所观察到的可变性是由中央电路中的噪声而不是感觉噪声引起的。我们提出的这种编码方案有利于粗气味和细气味的识别。更可靠的细胞能够快速区分不同的气味。然而，对于相似的气味，这些细胞重叠，不能提供区分信息。相比之下，更不可靠的细胞对类似的气味去关联，提供区分信息，尽管这些好处只有通过更多的试验和更长的训练才能获得。总之，我们在脊椎动物和无脊椎动物中发现了一个保守的、随机的编码方案，我们确定了一个候选机制，基于赢者通吃（WTA）抑制回路的可变性，通过训练提高了识别能力。噪声在生物系统中无处不在，干扰信号检测。生物系统可以通过降低噪音和提高信噪比来解决这个问题。这项研究揭示了另一种解决方案，表明嗅觉系统利用噪音来提高对类似刺激的辨别能力。
Sparse coding can improve discrimination of sensory stimuli by reducing overlap between their representations. Two factors, however, can offset sparse coding’s benefits: similar sensory stimuli have significant overlap and responses vary across trials. To elucidate the effects of these 2 factors, we analyzed odor responses in the fly and mouse olfactory regions implicated in learning and discrimination—the mushroom body (MB) and the piriform cortex (PCx). We found that neuronal responses fall along a continuum from extremely reliable across trials to extremely variable or stochastic. Computationally, we show that the observed variability arises from noise within central circuits rather than sensory noise. We propose this coding scheme to be advantageous for coarse- and fine-odor discrimination. More reliable cells enable quick discrimination between dissimilar odors. For similar odors, however, these cells overlap and do not provide distinguishing information. By contrast, more unreliable cells are decorrelated for similar odors, providing distinguishing information, though these benefits only accrue with extended training with more trials. Overall, we have uncovered a conserved, stochastic coding scheme in vertebrates and invertebrates, and we identify a candidate mechanism, based on variability in a winner-take-all (WTA) inhibitory circuit, that improves discrimination with training. Noise is ubiquitous in biological systems, and interferes with signal detection. Living systems can tackle this by tamping down noise and improving the signal-to-noise ratio. This study reveals another solution, showing that the olfactory system uses noise to improve the discrimination of similar stimuli.
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DOI：
10.1073/pnas.2102158118
发表时间：
2021-12-07
影响因子：
11.1
作者：
Abdelrahman NY;Vasilaki E;Lin AC
通讯作者：
Lin AC
影响因子：
7.7
作者：
Aso Y;Hattori D;Yu Y;Johnston RM;Iyer NA;Ngo TT;Dionne H;Abbott LF;Axel R;Tanimoto H;Rubin GM
通讯作者：
Rubin GM
影响因子：
7.7
作者：
Amin H;Apostolopoulou AA;Suárez-Grimalt R;Vrontou E;Lin AC
通讯作者：
Lin AC
DOI：
10.1523/jneurosci.2753-12.2013
发表时间：
2013-02-27
期刊：
The Journal of neuroscience : the official journal of the Society for Neuroscience
影响因子：
--
作者：
Barak O;Rigotti M;Fusi S
通讯作者：
Fusi S
影响因子：
3.4
作者：
Arazi A;Gonen-Yaacovi G;Dinstein I
通讯作者：
Dinstein I