Bilingualism has been shown to contribute to increased resilience against cognitive aging. One of the key brain structures linked to memory and dementia symptom onset, the hippocampus, has been observed to adapt in response to bilingual experience – at least in healthy individuals. However, in the context of neurodegenerative pathology, it is yet unclear what role previous bilingual experience might have in terms of sustaining integrity of this structure or related behavioral correlates. The present study adds to the limited cohort of research on the effects of bilingualism on neurocognitive outcomes in Mild Cognitive Impairment (MCI) using structural brain data. We investigate whether bilingual language experience (operationalized as language entropy) results in graded neurocognitive adaptations within a cohort of bilinguals diagnosed with MCI. Results reveal a non-linear effect of bilingual language entropy on hippocampal volume, although they do not predict episodic memory performance, nor age of MCI diagnosis.

双语已被证明有助于增强抵抗认知衰老的能力。海马体是与记忆和痴呆症状发作相关的关键大脑结构之一，据观察，它能够适应双语体验——至少在健康个体中是这样。然而，在神经退行性病理学的背景下，目前尚不清楚以前的双语经验在维持这种结构或相关行为相关性的完整性方面可能发挥什么作用。本研究利用大脑结构数据，对双语对轻度认知障碍（MCI）神经认知结果影响的有限研究进行了补充。我们调查了双语语言体验（可操作为语言熵）是否会导致诊断为 MCI 的双语者群体中的分级神经认知适应。结果揭示了双语语言熵对海马体积的非线性影响，尽管它们不能预测情景记忆表现，也不能预测 MCI 诊断的年龄。