Informational Masking of Communication Signals: Behavioral Constraints and Neural Mechanisms

通信信号的信息掩蔽：行为约束和神经机制

• 批准号: 2022253
• 负责人: Mark Bee
• 金额: $ 65万
• 依托单位: University of Minnesota-Twin Cities
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-05-01 至 2025-04-30
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2022253&HistoricalAwards=false
• 关键词: Informational; Masking; Communication; Signals; Behavioral

Vocal communication is fundamentally important in the social and sexual behaviors of humans and other animals. In many species, vocal communication occurs in large social groups, where high levels of background noise constrain a listener’s ability to hear and process vocalizations. In the context of human speech perception, these constraints are collectively known as the "cocktail party problem," which refers to the difficulty of following a conversation in a crowd. Recognizing speech in noise is particularly challenging for people with hearing loss. At present, how the noise of a crowd constrains the brain’s ability to recognize vocalizations is poorly understood at a cellular level. Discovering the origin of these constraints and their impacts on vocal recognition is necessary to advance knowledge of the neural basis of hearing and vocal communication. Treefrogs are one example of an animal that encounters and solves a biological analog of the human cocktail party problem. During their breeding season, male treefrogs gather around suitable bodies of water where they produce loud mating calls in dense and noisy choruses to attract females. In order to reproduce, a female treefrog must recognize the vocalizations of a calling male of her species amid the cacophony of a noisy breeding chorus. This project integrates behavioral experiments with neurophysiological recordings from individual neurons in a subcortical area of the vertebrate brain to identify the mechanisms by which noise interferes with a female treefrog’s ability to extract information about species identity from the calls of a potential mate. The public outreach component of this project involves the creation of a new museum exhibit called “Ear of the Beholder” at the Bakken Museum. The PI will host a formal graduate student exchange program between the labs of the PI and Co-PI and will have an extensive undergraduate research program with a special emphasis on under-represented populations in biological sciences.Noise interferes with signal processing in two fundamentally different ways. “Energetic” masking impairs signal detection in noise and occurs when signals and noise produce competing excitation in the same peripheral auditory filter, such that they directly compete on the auditory nerve. “Informational” masking occurs when competing sounds disrupt central processes for extracting signal information, which in turn degrades signal recognition. Most behavioral studies of masking in animal communication focus on energetic masking. Few studies have investigated the neural basis of informational masking at a cellular level in animal models. Consequently, significant gaps remain in understanding how noise causes a breakdown of neural processing to give rise to vocal constraints with evolutionary consequences. This project integrates behavioral experiments on mate choice with extracellular and in vivo, whole-cell recordings of interval-counting neurons in the anuran inferior colliculus to investigate informational masking in Cope’s gray treefrog (Hyla chrysoscelis). Female gray treefrogs only recognize sounds as mating calls when they exceed a threshold number of pulses in length, a process mediated by interval-counting neurons. This project tests the central hypothesis that concurrent sounds impair extraction of this temporal information by disrupting sound processing by temporally tuned interval-counting neurons in the inferior colliculus. Our working hypothesis is that informational masking increases the threshold number of pulses required for call recognition by altering the time-dependent integration of excitation and inhibition performed by interval-counting neurons. The expected outcome of this project is a better understanding of the neural mechanisms involved in hearing and vocal communication in noisy social groups.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

声音交流在人类和其他动物的社会和性行为中至关重要。在许多物种中，声音交流发生在大型社会群体中，高水平的背景噪音限制了听者听到和处理声音的能力。在人类语音感知的背景下，这些约束被统称为“鸡尾酒会问题”，指的是在人群中跟随谈话的困难。在噪音中识别语音对于听力损失的人来说尤其具有挑战性。目前，在细胞水平上，人们对人群的噪音如何限制大脑识别发声的能力还知之甚少。发现这些限制的起源及其对语音识别的影响是必要的，以推进听觉和语音交流的神经基础的知识。树蛙是一种遇到并解决类似于人类鸡尾酒会问题的生物学问题的动物。在繁殖季节，雄性树蛙聚集在合适的水体周围，在那里它们发出响亮的交配叫声，以密集而嘈杂的合唱吸引雌性。为了繁殖后代，雌性树蛙必须在嘈杂的繁殖合唱中识别出同类雄性的叫声。该项目整合了行为实验与神经生理学记录从单个神经元在皮层下区域的脊椎动物的大脑，以确定噪声干扰的机制与雌性树蛙的能力，从潜在的配偶的呼叫中提取有关物种身份的信息。该项目的公共宣传部分涉及在巴肯博物馆创建一个名为“旁观者的耳朵”的新博物馆展览。PI将在PI和Co-PI的实验室之间举办正式的研究生交流项目，并将开展广泛的本科生研究项目，特别强调生物科学中代表性不足的人群。噪声以两种根本不同的方式干扰信号处理。“能量”掩蔽损害噪声中的信号检测，并且当信号和噪声在相同的外周听觉滤波器中产生竞争性激励时发生，使得它们直接在听觉神经上竞争。当竞争性声音扰乱提取信号信息的中枢过程时，就会发生“信息”掩蔽，这反过来又会降低信号识别能力。大多数关于动物交流中掩蔽的行为研究都集中在能量掩蔽上。很少有研究在动物模型中在细胞水平上研究信息掩蔽的神经基础。因此，在理解噪声如何导致神经处理的崩溃从而引起具有进化后果的声音限制方面仍然存在重大差距。本研究整合了无尾两栖类下丘的细胞外和体内间隔计数神经元的全细胞记录，以研究科普灰树蛙（Hyla chrysoscelis）的信息掩蔽行为。雌性灰树蛙只有在超过脉冲长度阈值时才能将声音识别为交配呼叫，这一过程由间隔计数神经元介导。这个项目测试的中心假设，并发的声音损害提取这个时间信息的干扰声音处理的时间调谐的间隔计数神经元在下丘。我们的工作假设是，信息掩蔽通过改变由间隔计数神经元执行的兴奋和抑制的时间依赖性整合来增加呼叫识别所需的脉冲阈值数。该项目的预期成果是更好地理解嘈杂社会群体中听觉和语音交流所涉及的神经机制。该奖项反映了NSF的法定使命，并通过使用基金会的智力价值和更广泛的影响审查标准进行评估，被认为值得支持。

项目成果

In your CORT: Corticosterone and its receptors in the brain underlie mate choosiness in female Cope's gray treefrogs (Hyla chrysoscelis)

• DOI: 10.1016/j.yhbeh.2024.105477
• 发表时间: 2024-01-20
• 期刊: HORMONES AND BEHAVIOR
• 影响因子: 3.5
• 作者: -Santiago，Mariana Rodriguez;Ruppert，Annika;Baugh，Alexander T.
• 通讯作者: Baugh，Alexander T.

Female preferences for the spectral content of advertisement calls in Cope’s gray treefrog (Hyla chrysoscelis)

科普灰树蛙 (Hyla chrysoscelis) 中雌性对广告叫声的光谱内容的偏好

• DOI: 10.1007/s00359-022-01575-w
• 发表时间: 2023
• 期刊: Journal of Comparative Physiology A
• 作者: Gupta, Saumya;Bee, Mark A.
• 通讯作者: Bee, Mark A.