出生后头两周被隔离的大鼠幼仔可发出超声呼叫,频率为35～45kHz。这种呼叫可被高频声敏话筒检出并计数,借助计算机声图分析还可得到功率谱、频率峰值、呼叫间期等更为精细的特征。利眠宁、安定可以降低大鼠幼仔的超声呼叫数,其作用是特异的,因为降低 Rat pups isolated in the first two weeks of life can make ultrasound calls at a frequency of 35-45 kHz. Such calls can be detected by high-frequency acoustic microphones and count, with the help of computer sound image analysis can also get the power spectrum, frequency peaks, call intervals and other more sophisticated features. Limianning and diazepam can reduce the number of sonic calls in rat pups, and their effect is specific because of decreased