Freeman John H, Rabinak Christine A, Campolattaro Matthew M
Department of Psychology, University of Iowa, Iowa City, Iowa 52242, USA.
Learn Mem. 2005 May-Jun;12(3):255-9. doi: 10.1101/lm.91105.
Pontine neuronal activation during auditory stimuli increases ontogenetically between postnatal days (P) P17 and P24 in rats. Pontine neurons are an essential component of the conditioned stimulus (CS) pathway for eyeblink conditioning, providing mossy fiber input to the cerebellum. Here we examined whether the developmental limitation in pontine responsiveness to a CS in P17 rats could be overcome by direct stimulation of the CS pathway. Eyeblink conditioning was established in infant rats on P17-P18 and P24-P25 using pontine stimulation as a CS. There were no significant age-related differences in the rate or level of conditioning. Eyeblink conditioned responses established with the stimulation CS were abolished by inactivation of the ipsilateral cerebellar nuclei and overlying cortex in both age groups. The findings suggest that developmental changes in the CS pathway play an important role in the ontogeny of eyeblink conditioning.
在大鼠中，听觉刺激期间脑桥神经元的激活在出生后第（P）17天到第24天之间呈个体发育性增加。脑桥神经元是眨眼条件反射中条件刺激（CS）通路的重要组成部分，为小脑提供苔藓纤维输入。在这里，我们研究了在P17大鼠中，通过直接刺激CS通路是否可以克服脑桥对CS反应性的发育限制。在P17 - P18和P24 - P25的幼鼠中，使用脑桥刺激作为CS建立眨眼条件反射。在条件反射的速率或水平上，没有显著的年龄相关差异。在两个年龄组中，通过同侧小脑核和覆盖皮层的失活，消除了由刺激CS建立的眨眼条件反应。这些发现表明，CS通路的发育变化在眨眼条件反射的个体发育中起重要作用。
