普通伏翼蝠下丘神经元基本声反应特性

Acoustic Response Properties of the Inferior Colliculus in Pipistrellus abramus

自由声场条件下,采用单单位胞外微电极记录方法,研究了普通伏翼蝠(Pipistrellus abramus)下丘神经元基本声反应特性.结果发现,在所得的65个下丘神经元中:特征频率在18.9～76.7 kHz(42.94±11.29)之间,最小阈值在29.1～80.1dB SPL(58.65±12.62)之间,潜伏期在3.1～10.4 ms(6.10±1.47)之间;特征频率随记录深度的增加而增大,与最小阈值之间没有显著相关性;发放类型包括相位型(73.85%)、梳齿型(15.38%)和紧张型(10.77%)3种基本类型;频率调谐曲线均为开峰型,多数神经元(72.30%)调谐曲线较宽阔,少数(27.70%)较狭窄,并且多数神经元的频率调谐曲线高频边比低频边陡.

The present paper deals with the acoustic response properties of the inferior colliculus in Pipistrellus abramus based on the method of single unit extracellular recording with microelectrode in free field conditions. In the 65 recorded neurons, the results show： characteristic frequency （CF）, minimum threshold （MT） and response latency were between 18.9and76.7 kHz （42.94 ± 11.29）, 29.1 and 80.1 dB SPL （58.65 ± 12.62）, 3.1 and 13.4 ms （6. l0 ± 1.47）, respectively; CFs increased with the recording depth, but CF and MT were not correlated; there were three different types of discharge patterns in the inferior colliculus： phasic pattern （73.85%）, chopper （ 15.38 % ） and tonic （ 10.77 % ） ; the types of frequency tuning curves （FTC） were all V-shaped, most of which were wide types and few were narrow types. In addition, the high-frequency slope was often steeper than the low-frequency slope.