Civil Architectural and Environmental Engineering, The University of Texas at Austin, Austin, TX 78712, USA.
Center for Learning and Memory, Department of Neuroscience, The University of Texas at Austin, Austin, TX 78712, USA.
Ultrasonics. 2024 Jan;136:107170. doi: 10.1016/j.ultras.2023.107170. Epub 2023 Sep 25.
Rodent models of behavior used in the fields of neuroscience and psychology generate a wealth of multimodal data. For instance, as a rodent moves and behaves in its environment, muscle contractions apply subtle forces to any surface the animal contacts. These forces generate acoustic waves that propagate through the waveguide as Lamb and shear horizontal (SH) waves and contain information about the rodent's physiology, behavior, and underlying psychological state. If the information in these waves were to be tapped, it would provide a novel, non-invasive way to study rodent behavior. This article lays the foundations for using guided ultrasonic waves generated by a mouse's movement on an aluminum plate for detecting behavior and drawing inferences about acoustic startle responses. The experimental setup involves piezoelectric sensors capturing the waves generated by the rodent's movement, which are then stored as discrete acoustic emission (AE) hits using an amplitude threshold-based data acquisition system. This method of data acquisition ensures that data collection occurs only when the animal moves or behaves, and each movement/behavior is represented by values of features within the generated wavepackets (AE hits). Through open field tests with C57BL/6J mice, utilizing piezoelectric sensors and the DAQ system, it was observed that every movement/behavior of the animal generated Lamb wavepackets within the frequency range of 20 kHz to 100 kHz. Furthermore, rearing behavior in the animals also led to the generation of SH wavepackets in the frequency range of 75 kHz to 230 kHz. This criterion was subsequently employed to detect rearing behavior. In the acoustic startle response test, where the animals' responses to intense sound pulse were recorded, AE hits' features proved useful in quantifying the response. These experimental findings validate the proposed technology's practicality and demonstrate its capability to enhance studies of rodent behavior.
啮齿动物行为模型在神经科学和心理学领域产生了大量的多模态数据。例如，当啮齿动物在其环境中移动和行为时，肌肉收缩会对动物接触的任何表面施加微妙的力。这些力产生的声波通过波导以兰姆波和剪切水平（SH）波传播，包含有关啮齿动物生理、行为和潜在心理状态的信息。如果能够利用这些波中的信息，将为研究啮齿动物行为提供一种新颖的、非侵入性的方法。本文为利用老鼠在铝板上的运动产生的导超声波来检测行为并推断声惊反射奠定了基础。实验设置涉及压电传感器捕获啮齿动物运动产生的波，然后使用基于幅度阈值的数据采集系统将其存储为离散声发射（AE）命中。这种数据采集方法确保仅在动物移动或行为时才进行数据收集，并且每个运动/行为都由生成的波包（AE 命中）内的特征值表示。通过利用压电传感器和 DAQ 系统对 C57BL/6J 小鼠进行的旷场测试，观察到动物的每一个运动/行为都会在 20 kHz 到 100 kHz 的频率范围内产生兰姆波包。此外，动物的后肢站立行为也会在 75 kHz 到 230 kHz 的频率范围内产生 SH 波包。随后，采用这一标准来检测后肢站立行为。在对动物对强烈声音脉冲的反应进行记录的声惊反射测试中，AE 命中的特征在定量反应方面非常有用。这些实验结果验证了所提出技术的实用性，并证明了其增强啮齿动物行为研究的能力。
