Northcutt R G, Plassmann W
Neurobiology Unit, Scripps Institution of Oceanography, La Jolla, CA.
Neurosci Lett. 1989 Apr 24;99(1-2):79-84. doi: 10.1016/0304-3940(89)90268-1.
Electrical shock of the anterior lateral line nerve evokes slow wave potentials in the contralateral corpus striatum and bilaterally in the medial pallium of the telencephalon of axolotls. The onset latency of the evoked response in the medial pallium (70 ms) is considerably longer than that of the corpus striatum (46 ms). Quasi-natural stimuli, such as weak uniform electric fields (100 microV/cm) or water drops striking the surface of the water surrounding the axolotls elicited evoked potentials or multiple unit activity in the corpus striatum but not in the medial pallium. Striatal responses to weak electric fields have a threshold of approximately 50 microV/cm and habituate at rates higher than 1 every 10 s. Multiple-unit responses in the medial pallium were elicited only by gentle strokes to the snout with a brush, and it is possible that trigeminal fibers were inadvertently stimulated in the nerve shock cases. The discovery that the corpus striatum is a major telencephalic target of electrosensory information rather than the medial pallium as reported in elasmobranch fishes, suggests that there are additional electrosensory telencephalic centers in elasmobranchs and/or that homologous nuclei of the midbrain or thalamus have evolved different projections.
电刺激美西螈前侧线神经会在对侧纹状体以及双侧端脑的内侧 pallium 中诱发慢波电位。内侧 pallium 中诱发反应的起始潜伏期（70 毫秒）比纹状体（46 毫秒）长得多。准自然刺激，如弱均匀电场（100 微伏/厘米）或水滴撞击美西螈周围水面，会在纹状体中诱发诱发电位或多单位活动，但在内侧 pallium 中则不会。纹状体对弱电场的反应阈值约为 50 微伏/厘米，且以高于每 10 秒 1 次的速率产生习惯化。内侧 pallium 中的多单位反应仅由用刷子轻轻触碰吻部引发，并且在神经休克病例中有可能无意中刺激了三叉神经纤维。与在板鳃鱼类中所报道的不同，纹状体是电感觉信息的主要端脑靶点而非内侧 pallium，这一发现表明板鳃鱼类中存在额外的电感觉端脑中心，和/或中脑或丘脑的同源核已经进化出了不同的投射。
