Active Touch Laboratory (ATL@S), Department of Psychology, The University of Sheffield, Sheffield S10 2TN, UK.
Philos Trans R Soc Lond B Biol Sci. 2011 Nov 12;366(1581):3037-48. doi: 10.1098/rstb.2011.0156.
In rats, the long facial whiskers (mystacial macrovibrissae) are repetitively and rapidly swept back and forth during exploration in a behaviour known as 'whisking'. In this paper, we summarize previous evidence from rats, and present new data for rat, mouse and the marsupial grey short-tailed opossum (Monodelphis domestica) showing that whisking in all three species is actively controlled both with respect to movement of the animal's body and relative to environmental structure. Using automatic whisker tracking, and Fourier analysis, we first show that the whisking motion of the mystacial vibrissae, in the horizontal plane, can be approximated as a blend of two sinusoids at the fundamental frequency (mean 8.5, 11.3 and 7.3 Hz in rat, mouse and opossum, respectively) and its second harmonic. The oscillation at the second harmonic is particularly strong in mouse (around 22 Hz) consistent with previous reports of fast whisking in that species. In all three species, we found evidence of asymmetric whisking during head turning and following unilateral object contacts consistent with active control of whisker movement. We propose that the presence of active vibrissal touch in both rodents and marsupials suggests that this behavioural capacity emerged at an early stage in the evolution of therian mammals.
在大鼠中，长面须（mystacial macrovibrissae）在探索过程中会反复快速地前后扫动，这种行为被称为“刷动”。在本文中，我们总结了以前大鼠的证据，并提出了新的数据，证明大鼠、小鼠和有袋动物灰短尾负鼠（Monodelphis domestica）的刷动行为都是主动控制的，无论是相对于动物的身体运动还是相对于环境结构。我们使用自动胡须跟踪和傅里叶分析，首先表明，在水平面上，面须的刷动运动可以近似为两个基频（大鼠、小鼠和负鼠的平均值分别为 8.5、11.3 和 7.3 Hz）及其二次谐波的正弦波的混合。在小鼠中，二次谐波的振荡特别强烈（约 22 Hz），与该物种快速刷动的先前报道一致。在所有三种物种中，我们发现了头部转动和单侧物体接触时不对称刷动的证据，这与主动控制胡须运动一致。我们提出，啮齿动物和有袋动物中存在主动触须触觉表明，这种行为能力在有胎盘哺乳动物的进化早期就出现了。
