Wiel D E, Weeks J C
Institute of Neuroscience, University of Oregon, Eugene 97403-1254, USA.
Behav Neurosci. 1996 Oct;110(5):1133-47.
The neural circuit for the proleg withdrawal reflex (PWR) of Manduca sexta larvae exhibits activity-dependent plasticity. This study demonstrates habituation and dishabituation of PWR behavior. Repeated deflection of 1 or 5 mechanosensory hairs on a proleg at a 60-s interstimulus interval (ISI) for 20 trials produced a significant decrease in evoked force of proleg withdrawal. Habituation was similar with 30-s and 60-s ISIs and nonsignificant with a 5-min ISI or without repeated stimulation. Habituated responses recovered after cessation of stimulation or pinch of the body wall (dishabituation). The role of intersegmental influences was tested by severing connectives to leave different numbers of ganglia connected to the test segment. Habituation was robust even in test segments that were disconnected from the rest of the central nervous system. The PWR of Manduca is appropriate for further analysis of cellular mechanisms underlying learning.
烟草天蛾幼虫腹足退缩反射（PWR）的神经回路表现出活动依赖的可塑性。本研究证明了PWR行为的习惯化和去习惯化。以60秒的刺激间隔（ISI）对腹足上的1根或5根机械感觉毛进行重复偏转，共20次试验，结果显示腹足退缩的诱发力显著下降。30秒和60秒的ISI时习惯化情况相似，5分钟的ISI或无重复刺激时习惯化不显著。刺激停止或捏身体壁后，习惯化反应恢复（去习惯化）。通过切断连接体以留下与测试节段相连的不同数量神经节，来测试节段间影响的作用。即使在与中枢神经系统其他部分断开连接的测试节段中，习惯化也很明显。烟草天蛾的PWR适合进一步分析学习背后的细胞机制。
