Neural integration of electrocommunication signals encoded in parallel sensory processing streams.

多感官整合将不同感官提供的信息连接到一个统一的感知中。在信息相互冲突的情况下，这可能会导致知觉的变化，如腹语错觉。然而，组合来自多个感官的一致信息通常会通过减少反应时间或改进刺激检测来改善行为表现。通常，这种集成是贝叶斯最优的，也就是说，信息通道根据它们各自的可靠性来加权。在神经元水平上，反应增强、反应潜伏期缩短和改进的相位锁定被描述为多感觉整合的效果。许多研究已经研究了来自多个渠道的信息是如何整合的。为了理解指导原则，已经开发了数学模型和现象学模型。然而，我们对这些计算原理背后的生理过程的理解仍然薄弱。特别是，允许研究亚阈值机制的电生理学数据缺失。我们将在弱电鱼类绿色特征曼尼亚中对电子通信信号进行编码的背景下，解决理论和生理学之间的差距。在本征曼尼亚，通讯信号，称为啁啾，是鱼自己的电子器官放电的调制，刺激三个平行的电感觉通路。最初，信息是分开处理的，但最终连接到中脑的半圆环(TS)，这是哺乳动物下丘的硬骨同源物。我们之前对电感受器水平的分析表明，应该通过结合来自平行通路的信息来提高啁啾检测。通过对后脑平行通道神经元的在体细胞内记录，以及丘脑束旁核整合和非整合神经元的记录，我们将收集突触前和突触后活动所需的数据，以分析阈值下整合的机制。在这项拟议的研究中，我们旨在解决有关后脑和中脑整合和非整合神经元中电通信信号编码的公开问题。基于所获得的数据，我们将分析丘脑束核多通道神经元整合过程中涉及的亚阈值机制。这些将在已知的多感官整合理论的背景下进行解释。

Multisensory integration joins information provided by different senses into a unified percept. In situations of conflicting information it may lead to perceptional shifts such as the ventriloquist illusion. Combining congruent information from multiple senses, however, often improves behavioral performances by reduced reaction times or improved stimulus detection. Often, this integration is Bayes-optimal, that is, information channels are weighted according to their respective reliability. On the neuronal level, increased responsiveness, reduced response latencies, and improved phase locking have been described as effects of multisensory integration. How information from multiple channels is integrated has been investigated in a multitude of studies. Mathematical as well as phenomenological models have been developed to understand the guiding principles. However, our understanding of the physiolgical processes underlying these computational principles is still weak. In particular, electrophysiological data allowing to investigate the subthreshold mechanisms are missing. We will address this gap between theory and physiology in the context of the encoding of electrocommunication signals in the weakly electric fish Eigenmannia virescens. In Eigenmannia, communication signals, called chirps, are modulations of the fish's own electric organ discharge which stimulates three parallel electrosensory pathways. Initially, information is processed separately, but is eventually joined in the torus semicircularis (TS) of the midbrain, the teleost homolog to the mammalian inferior colliculus. Our previous analyses on the level of the electroreceptors suggest that chirp detection should be improved by combining information from the parallel pathways. By means of in vivo intracellular recordings of neurons in the parallel channels in the hindbrain and of integrating and non-integrating neurons in the TS we will gather the required data of pre- and postsynaptic activity to analyze the mechanism of integration in the subthreshold regime. With the proposed study we aim at open questions regarding the encoding of electrocommunication signals in integrating and non-integrating neurons in the hind- and midbrain. Based on the acquired data we will analyze the subthreshold mechansims involved in the integration processes in multichannel neurons in the TS. These will be interpreted in the context of the known theories of multisensory integration.