Sevelinges Yannick, Moriceau Stephanie, Holman Parker, Miner Cathrine, Muzny Kyle, Gervais Remi, Mouly Anne-Marie, Sullivan Regina M
Institut des Sciences Cognitives, Université Claude Bernard Lyon 1, France.
Biol Psychiatry. 2007 Nov 15;62(10):1070-9. doi: 10.1016/j.biopsych.2007.04.025. Epub 2007 Sep 10.
Early life adverse experience alters adult emotional and cognitive development. Here we assess early life learning about adverse experience and its consequences on adult fear conditioning and amygdala activity.
Neonatal rats were conditioned daily from 8-12 days-old with paired odor (conditioned stimulus, CS) .5mA shock, unpaired, odor-only, or naive (no infant conditioning). In adulthood, each infant training group was divided into three adult training groups: paired, unpaired or odor-only, using either the same infant CS odor, or a novel adult CS odor without or with the infant CS present as context. Adults were cue tested for freezing (odor in novel environment), with amygdala (14)C 2-DG autoradiography and electrophysiology assessment.
Infant paired odor-shock conditioning attenuated adult fear conditioning, but only if the same infant CS odor was used. The (14)C 2-DG activity correlated with infant paired odor-shock conditioning produced attenuated amygdala but heightened olfactory bulb activity. Electrophysiological amygdala assessment further suggests early experience causes changes in amygdala processing as revealed by increased paired-pulse facilitation in adulthood.
This suggests some enduring effects of early life adversity (shock) are under CS control and dependent upon learning for their impact on later adult fear learning.
早年不良经历会改变成年后的情绪和认知发展。在此，我们评估早年对不良经历的学习及其对成年期恐惧条件反射和杏仁核活动的影响。
新生大鼠在8至12日龄时每天接受配对气味（条件刺激，CS）与0.5毫安电击、非配对、仅气味或未处理（无婴儿期条件反射）的训练。成年后，每个婴儿期训练组再分为三个成年期训练组：配对、非配对或仅气味组，使用相同的婴儿期CS气味，或在有无婴儿期CS作为背景的情况下使用新的成年期CS气味进行训练。对成年大鼠进行线索测试以评估僵住反应（在新环境中的气味），并进行杏仁核[14C]2-脱氧葡萄糖放射自显影和电生理评估。
婴儿期配对气味-电击条件反射减弱了成年期恐惧条件反射，但前提是使用相同的婴儿期CS气味。[14C]2-脱氧葡萄糖活性与婴儿期配对气味-电击条件反射相关，该条件反射使杏仁核活动减弱，但使嗅球活动增强。电生理杏仁核评估进一步表明，早年经历会导致成年期杏仁核处理过程发生变化，表现为成年期配对脉冲易化增强。
这表明早年逆境（电击）的一些持久影响受条件刺激控制，并依赖于学习来影响后期成年期恐惧学习。
