Tang Akaysha C, Reeb Bethany C, Romeo Russell D, McEwen Bruce S
Department of Psychology, University of New Mexico, Albuquerque, New Mexico 87131, USA.
J Neurosci. 2003 Sep 10;23(23):8254-60. doi: 10.1523/JNEUROSCI.23-23-08254.2003.
Although corticosterone (a stress hormone) is known to influence social behavior and memory processes, little has been explored concerning its modulatory role in social recognition. In rats, social recognition memory for conspecifics typically lasts <2 hr when evaluated using a habituation paradigm. Using neonatal novelty exposure, a brief and transient early life stimulation method known to produce long-lasting changes in the hypothalamic-pituitary-adrenal axis, we found that social recognition memory was prolonged to at least 24 hr during adulthood. This prolonged social memory was paralleled by a reduction in the basal blood concentration of corticosterone. The same neonatal stimulation also resulted in a functional asymmetry expressed as a greater right-turn preference in a novel environment. Rats that preferred to turn right showed better social recognition memory. These inter-related changes in basal blood corticosterone concentration, turning asymmetry, and social recognition memory suggest that stress hormones and brain asymmetry are likely candidates for modulating social memory. Furthermore, given that neonatal stimulation has been shown to improve learning and memory performance primarily under aversive learning situations, the neonatal novelty exposure-induced enhancement in social recognition broadens the impact of early life stimulation to include the social domain.
虽然已知皮质酮（一种应激激素）会影响社会行为和记忆过程，但关于其在社会认知中的调节作用却鲜有研究。在大鼠中，当使用习惯化范式评估时，对同种个体的社会认知记忆通常持续时间小于2小时。通过新生期新奇刺激（一种已知能在下丘脑 - 垂体 - 肾上腺轴产生持久变化的短暂早期生活刺激方法），我们发现成年期的社会认知记忆延长至至少24小时。这种延长的社会记忆伴随着皮质酮基础血浓度的降低。相同的新生期刺激还导致了一种功能不对称，表现为在新环境中更倾向于向右转。倾向于向右转的大鼠表现出更好的社会认知记忆。基础血皮质酮浓度、转向不对称和社会认知记忆的这些相互关联的变化表明，应激激素和大脑不对称可能是调节社会记忆的因素。此外，鉴于新生期刺激已被证明主要在厌恶学习情境下能改善学习和记忆表现，新生期新奇刺激诱导的社会认知增强将早期生活刺激的影响扩展到了社会领域。
