Yao Juan, Wu Bing, Wu Guang-Yan, Li Xuan, Ye Jian-Ning, Sui Jian-Feng
Department of Physiology, College of Basic Medical Science, Third Military Medical University, Chongqing, P.R. China.
Experimental Center of Basic Medicine, College of Basic Medical Science, Third Military Medical University, Chongqing, P.R. China.
PLoS One. 2017 Jun 2;12(6):e0178502. doi: 10.1371/journal.pone.0178502. eCollection 2017.
The present experiment was designed to determine whether classical eyeblink conditioning (EBC) can be established by using electrical microstimulation of the hippocampus as a conditioned stimulus (CS) paired with an air-puff unconditioned stimulus (US). We intended to examine whether EBC transfer could occur when a CS was shifted between microstimulation of the hippocampus as a CS (Hip-CS) and tone as a CS (tone-CS) and to compare the difference in transfer effectiveness between delay EBC (dEBC) and trace EBC (tEBC). Eight groups of guinea pigs, including 4 experimental groups and 4 control groups, were included in the study. First, the experimental groups received either a Hip-CS or a tone-CS paired with a US; then, these groups were exposed to a shifted CS (tone-CS or Hip-CS) paired with the US. The control groups received the corresponding Hip-CS or tone-CS, which was, however, pseudo-paired with the US. The control groups were then shifted to the tone-CS (or Hip-CS) paired with the US. The results show that EBC can be successfully established when using microstimulation of the hippocampus as a CS paired with an air-puff US, and that the acquisition rates of EBC are higher in the experimental groups than in the control groups after switching from the Hip-CS to the tone-CS or vice versa, indicating the occurrence of learning transfer between EBC established with the Hip-CS and tone-CS. The present study also demonstrated that the EBC re-acquisition rates were remarkably higher in dEBC than in tEBC with both types of transfer, which suggests that the saving effect was more evident in dEBC than tEBC. These results significantly expand our knowledge of EBC transfer as well as the functional neural circuit underlying EBC transfer.
本实验旨在确定是否可以通过将海马体的电微刺激作为条件刺激（CS）与吹气非条件刺激（US）配对来建立经典眨眼条件反射（EBC）。我们打算研究当CS在作为CS的海马体微刺激（Hip-CS）和作为CS的音调（tone-CS）之间转换时，EBC转移是否会发生，并比较延迟EBC（dEBC）和痕迹EBC（tEBC）之间转移效果的差异。该研究包括八组豚鼠，其中四组为实验组，四组为对照组。首先，实验组接受与US配对的Hip-CS或tone-CS；然后，这些组接受与US配对的转换后的CS（tone-CS或Hip-CS）。对照组接受相应的Hip-CS或tone-CS，但与US伪配对。然后对照组转换为与US配对的tone-CS（或Hip-CS）。结果表明，当使用海马体微刺激作为与吹气US配对的CS时，可以成功建立EBC，并且在从Hip-CS转换为tone-CS或反之亦然后，实验组的EBC习得率高于对照组，这表明在由Hip-CS和tone-CS建立的EBC之间发生了学习转移。本研究还表明，在两种类型的转移中，dEBC的EBC重新习得率明显高于tEBC，这表明节省效应在dEBC中比在tEBC中更明显。这些结果显著扩展了我们对EBC转移以及EBC转移背后的功能性神经回路的认识。
