Abstract Research has suggested that using two or more languages on a daily basis helps older adults maintain a heightened functional state and improves neurocomputational efficiency. In this review, we discuss studies that have examined the effect of life-long bilingualism on age-related cognitive and neural decline, with a focus on discrepancies between different sources of evidence. We intend to outline and characterize factors which might explain inconsistencies between studies claiming that bilingualism has neurocognitive benefits and those that failed to find such evidence. We argue that individual variation in language proficiency and exposure, especially language switching frequency and daily frequency of use of the two languages, likely account for a significant chunk of the inconsistencies found in the literature and constrain the effectiveness of bilingualism as a cognitive and brain reserve factor. Finally, we briefly review studies of cognitive intervention and speculate on the potential of developing language training protocols to increase cognitive and neural resilience in older adults.

中文翻译：

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双语和老龄化：重点神经科学评论

摘要 研究表明，每天使用两种或更多语言有助于老年人保持高度的功能状态并提高神经计算效率。在这篇综述中，我们讨论了研究终生双语对与年龄相关的认知和神经衰退的影响的研究，重点是不同证据来源之间的差异。我们打算概述和描述可能解释声称双语具有神经认知益处的研究与未能找到此类证据的研究之间不一致的因素。我们认为语言能力和接触的个体差异，尤其是语言转换频率和两种语言的日常使用频率，可能是文献中发现的大部分不一致的原因，并限制了双语作为认知和大脑储备因素的有效性。最后，我们简要回顾了认知干预的研究，并推测了开发语言训练方案以提高老年人认知和神经弹性的潜力。