Ebner Natalie C, Kamin Hayley, Diaz Vanessa, Cohen Ronald A, MacDonald Kai
Department of Psychology, University of Florida Gainesville, FL, USA ; Department of Aging and Geriatric Research, University of Florida Gainesville, FL, USA.
Department of Psychology, University of Florida Gainesville, FL, USA.
Front Psychol. 2015 Jan 22;5:1595. doi: 10.3389/fpsyg.2014.01595. eCollection 2014.
Aging is associated with well-recognized alterations in brain function, some of which are reflected in cognitive decline. While less appreciated, there is also considerable evidence of socioemotional changes later in life, some of which are beneficial. In this review, we examine age-related changes and individual differences in four neuroendocrine systems-cortisol, estrogen, testosterone, and oxytocin-as "difference makers" in these processes. This suite of interrelated hormonal systems actively coordinates regulatory processes in brain and behavior throughout development, and their level and function fluctuate during the aging process. Despite these facts, their specific impact in cognitive and socioemotional aging has received relatively limited study. It is known that chronically elevated levels of the stress hormone cortisol exert neurotoxic effects on the aging brain with negative impacts on cognition and socioemotional functioning. In contrast, the sex hormones estrogen and testosterone appear to have neuroprotective effects in cognitive aging, but may decrease prosociality. Higher levels of the neuropeptide oxytocin benefit socioemotional functioning, but little is known about the effects of oxytocin on cognition or about age-related changes in the oxytocin system. In this paper, we will review the role of these hormones in the context of cognitive and socioemotional aging. In particular, we address the aforementioned gap in the literature by: (1) examining both singular actions and interrelations of these four hormonal systems; (2) exploring their correlations and causal relationships with aspects of cognitive and socioemotional aging; and (3) considering multilevel internal and external influences on these hormone systems within the framework of explanatory pluralism. We conclude with a discussion of promising future research directions.
衰老与大脑功能中一些广为人知的变化相关，其中一些变化反映在认知能力下降上。虽然不太受关注，但也有大量证据表明，人在晚年还会出现社会情感变化，其中一些变化是有益的。在这篇综述中，我们研究了四个神经内分泌系统——皮质醇、雌激素、睾酮和催产素——与年龄相关的变化以及个体差异，将其视为这些过程中的“差异制造者”。这一套相互关联的激素系统在整个发育过程中积极协调大脑和行为的调节过程，并且它们的水平和功能在衰老过程中会发生波动。尽管如此，它们在认知和社会情感衰老方面的具体影响受到的研究相对有限。已知应激激素皮质醇的长期高水平会对衰老的大脑产生神经毒性作用，对认知和社会情感功能产生负面影响。相比之下，性激素雌激素和睾酮在认知衰老方面似乎具有神经保护作用，但可能会降低亲社会行为。较高水平的神经肽催产素有利于社会情感功能，但关于催产素对认知的影响或催产素系统与年龄相关的变化知之甚少。在本文中，我们将综述这些激素在认知和社会情感衰老背景下的作用。特别是，我们通过以下方式弥补文献中上述的空白：（1）研究这四个激素系统的单独作用和相互关系；（2）探索它们与认知和社会情感衰老各方面的相关性和因果关系；（3）在解释多元论的框架内考虑对这些激素系统的多层次内部和外部影响。我们最后讨论了有前景的未来研究方向。
