Coombs S, Montgomery J
Parmly Hearing Institute, Loyola University of Chicago, IL 60626.
Brain Behav Evol. 1994;44(6):287-98. doi: 10.1159/000113590.
Extracellular recording techniques were used to measure frequency response functions of anterior and posterior lateral line nerve fibers innervating superficial neuromasts at five different locations on the head and trunk of an antarctic notothenioid fish, Trematomus bernacchii. Scanning electron microscopy was used to measure neuromast size according to location. Fibers innervating neuromasts from all locations were similar in showing equal responsiveness in the 10-30 Hz range to equal pk-pk velocity levels of a sinusoidally vibrating sphere. The mean cut-off frequency (CF) at which responsiveness declined to 50% of maximum was 46 Hz for all fibers combined. Superficial neuromasts located on the ventral trunk line were three to six times larger in surface area than most other neuromasts. The mean CF for fibers innervating these large neuromasts was 7-18 Hz lower than mean CF's corresponding to other superficial neuromast locations, but small differences in mean CF's were not consistently related to neuromast size. It is argued that fiber responses from different superficial neuromasts are more similar than dissimilar and that the evolution of large superficial neuromasts on the ventral trunk line is linked to a general paedomorphic trend among notothenioid fishes that may be essentially non-adaptive for the lateral line.
采用细胞外记录技术，测量了南极南极鱼（Trematomus bernacchii）头部和躯干五个不同位置的支配浅层神经丘的前侧线神经纤维和后侧线神经纤维的频率响应函数。利用扫描电子显微镜根据位置测量神经丘大小。支配所有位置神经丘的纤维在10 - 30Hz范围内对正弦振动球体的相同峰 - 峰值速度水平表现出相同的响应。所有纤维组合的响应性下降到最大值的50%时的平均截止频率（CF）为46Hz。位于腹侧躯干线上的浅层神经丘的表面积比大多数其他神经丘大3至6倍。支配这些大型神经丘的纤维的平均CF比对应于其他浅层神经丘位置的平均CF低7 - 18Hz，但平均CF的微小差异与神经丘大小并不始终相关。有人认为，来自不同浅层神经丘的纤维反应相似之处多于不同之处，并且腹侧躯干线上大型浅层神经丘的进化与南极鱼中普遍存在的幼态持续趋势有关，这种趋势可能对侧线基本上是非适应性的。
