Ruusuvirta Timo, Koivisto Kalle, Wikgren Jan, Astikainen Piia
Cognitive Brain Research Unit, Department of Psychology, PO Box 9, 00014 University of Helsinki, Helsinki, Finland.
Eur J Neurosci. 2007 Aug;26(3):701-3. doi: 10.1111/j.1460-9568.2007.05687.x. Epub 2007 Jul 18.
The human brain can automatically detect changes even in repeated melodic contours of spectrally varying sounds. However, it is unclear whether this ability is specific to humans. We recorded event-related potentials (ERPs) in urethane-anaesthetized Wistar rats presented with rare pairs of tones ('deviants') interspersed with frequently repeated ones ('standards'). The frequency of the tones varied nonsystematically across their pairs so that deviants stood out from standards only in the melodic ordering (ascending or descending) of the tones of a pair. We found that the absolute amplitude of the ERP was significantly higher to deviants than standards between 106 and 136 ms from the onset of the deviance, suggesting that the ability to automatically detect changes in higher-order invariant attributes that emerge from consecutive sounds is not specific to humans.
即使是在频谱变化声音的重复旋律轮廓中，人类大脑也能自动检测到变化。然而，这种能力是否为人类所特有尚不清楚。我们记录了用乌拉坦麻醉的Wistar大鼠的事件相关电位（ERP），这些大鼠会听到罕见的成对音调（“偏差音”），其间穿插着频繁重复的音调（“标准音”）。每对音调的频率无系统变化，因此偏差音仅在一对音调的旋律顺序（升序或降序）上与标准音不同。我们发现，从偏差开始起106至136毫秒内，ERP对偏差音的绝对振幅显著高于对标准音的绝对振幅，这表明自动检测连续声音中出现的高阶不变属性变化的能力并非人类所特有。
