中文摘要：

声音通讯对发声动物的生存和繁殖起着重要作用.但动物鸣声在时域上不同组成部分的生物学意义差异尚无定论.无尾两栖类的鸣声一般由音节和间隔组成,如雄性仙琴蛙 daimctoia的广告鸣叫由一至十余个音节及持续时间约为150ms的间隔组成,这为研究不同音节生物学意义的差异提供了便利.本研究采用优化的失匹配负波（MMN）范式,在播放标准刺激（白噪声）和偏差刺激（同一个广告鸣叫的5个音节）时,采集脑电信号,经过叠加平均后得到MMN.结果显示,第一个音节对应的MMN幅度最高,而且具有大脑左侧优势.由于MMN幅度表征刺激与记忆痕迹之间的差异,同时反映投入的大脑资源,据此推测第一个音节在蛙类声音通讯中起至关重要的作用.

英文摘要：

Complex acoustic communication sounds play a crucial role in coordinating social and reproductive behaviors in many terrestrial species. However, the biological significance of each component of such complex sounds is still unclear. Most of the calls of male anuran species are composed of a series of notes and intervals. For example, advertisement calls of the male Emei music frog {Babina daunchina） frequently contain one to ten or more notes that are separated by intervals of approximately 150 ms. Therefore, Emei music frog is an interesting model to explore the biological significance of each note. By using the optimized paradigm of mismatch negativity （MMN） , one standard stimulus （white noise） and 5 deviant stimuli （5 notes from one advertisement call） were played back to frogs and multichannel electroencephalogram recordings were then obtained. The results showed that the MMN amplitudes were greater in the left hemisphere, indicating a left brain advantage for perceiving these deviations. While the MMN amplitude of the first note was significantly larger than that of oth-ers. Since the MMN amplitude is thought to reflect not only the difference between the standard and deviant stimuli, but also the brain resources devoted to cognitive processing, it is reasonable to speculate that the first note is the most important unit of vocal communication in frogs.