线虫嗅觉组合编码支持风险–奖励决策：1-辛醇同时被编码为吸引与排斥信号
Olfactory combinatorial coding supports risk–reward decision-making in Caenorhabditis elegans
利用全网络 Ca²⁺ 成像研究秀丽隐杆线虫（Caenorhabditis elegans）的嗅觉编码，发现气味分子 1-辛醇在外周被组合编码为吸引和排斥两种信号。这两类输入在中枢整合，其相对强度通过调节运动倒退与速度决定行为反应的敏感性和效价。该通路的平衡同时决定控制运动倒退的运动指令中间神经元活动，构成反应调制的调控节点，使线虫在形成行为反应时权衡环境中的机会与危险。因此，同一气味可同时被编码为效价相反的两类输入，感知、反应与可塑性的关键在于这些输入的整合。
来源：eLife · doi.org
Olfactory-driven behaviors are essential for animal survival, but mechanisms for decoding olfactory inputs remain poorly understood. We have used whole-network Ca 2+ imaging to study olfactory coding in Caenorhabditis elegans . We show that the odorant 1-octanol is encoded combinatorially in the periphery as both an attractant and a repellent. These inputs are integrated centrally, and their relative strengths determine the sensitivity and valence of the behavioral response through modulation of locomotory reversals and speed. The balance of these pathways also dictates the activity of the locomotory command interneurons, which control locomotory reversals. This balance serves as a regulatory node for response modulation, allowing C. elegans to weigh opportunities and hazards in its environment when formulating behavioral responses. Thus, an odorant can be encoded simultaneously as inputs of opposite valence, focusing attention on the integration of these inputs in determining perception, response, and plasticity.