Department of Psychology University of Toronto at Mississauga 3359 Mississauga Rd. North, Mississauga Ontario, Canada L5L 1C6.
Dev Psychobiol. 2010 Mar;52(2):142-8. doi: 10.1002/dev.20422.
Complete maternal deprivation in rats, through artificial rearing (AR), produces deficits in subsequent maternal behavior of the offspring. These deficits are partially reversed when isolated pups are provided with additional tactile stimulation designed to simulate maternal licking (e.g., Gonzalez et al. [2001] Developmental Psychobiology, 38, 11-32). These findings highlight the importance of the early maternal environment in subsequent development. However, given the possibility that prenatal environments may differ between AR and maternally reared (MR) offspring, the deficits in the behavior of AR mothers may be driven by the characteristics of their pups derived from the effects of an altered prenatal environment. Hence differences in the neonatal pups of AR mothers may produce the alterations in the AR maternal behavior. To rule out this possibility, we employed a fostering paradigm where AR and MR mothers received cross-fostered mother-reared pups. AR mothers showed the same level of deficits in maternal behavior towards MR foster pups as they do with their own pups and these deficits were partially reversed with additional tactile stimulation. Hence, maternal behavior deficits reported in mothers who had been reared in isolation are due primarily to the direct effects of the earlier experience on mechanisms regulating their maternal behavior and not to the effects on their offspring.
在大鼠中完全剥夺母体（通过人工养育，AR）会导致后代随后的母性行为缺陷。当将孤立的幼崽提供额外的旨在模拟母体舔舐的触觉刺激（例如 Gonzalez 等人，[2001] 发展心理生物学，38，11-32）时，这些缺陷会部分得到逆转。这些发现强调了早期母体环境对随后发展的重要性。然而，鉴于 AR 和由母体养育（MR）的后代之间的产前环境可能存在差异，AR 母亲行为的缺陷可能是由其幼崽的特征驱动的，这些特征源自产前环境改变的影响。因此，AR 母亲的新生幼崽的差异可能导致 AR 母性行为的改变。为了排除这种可能性，我们采用了寄养范式，其中 AR 和 MR 母亲接受了交叉寄养的母系养育的幼崽。AR 母亲对 MR 寄养幼崽的母性行为表现出与对自己幼崽相同的缺陷水平，并且这些缺陷在进行额外的触觉刺激后部分得到逆转。因此，在隔离中养育的母亲报告的母性行为缺陷主要是由于早期经验对调节其母性行为的机制的直接影响，而不是对其后代的影响。
