Although the question of whether and how bilingualism affects executive functions has been extensively debated, less attention has been paid to the cognitive abilities of speakers of different varieties of the same language, in linguistic situations such as bidialectalism and diglossia. Similarly to the bilingual situation, in bidialectalism and diglossia speakers have two language varieties that are active at the same time. However, these situations have been argued to potentially provide varied, and possibly fewer, opportunities for mixing or switching between the varieties, which may in turn lead to different cognitive outcomes than those reported in bilingualism. Here we review the available evidence on the effects of bidialectalism and diglossia on cognition, and evaluate it in relation to theories of the effects of bilingualism on cognition. We conclude that investigations of bilingualism, bidialectalism and diglossia must take into account the conversational context and, in particular, the opportunities for language switching that this affords.

中文翻译：

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使用一种语言的两种变体对认知的影响

尽管双语是否以及如何影响执行功能的问题已被广泛争论，但很少有人关注同一语言不同变体的使用者在双方言和双语等语言环境中的认知能力。与双语情况类似，双方言和双语使用者有两种同时活跃的语言变体。然而，这些情况被认为可能提供不同的、甚至可能更少的混合或切换机会，这反过来可能会导致与双语情况不同的认知结果。在这里，我们回顾了关于双语和双语对认知影响的现有证据，并根据双语对认知影响的理论对其进行了评估。我们的结论是，对双语、双方言和双语的研究必须考虑到对话环境，特别是由此提供的语言转换的机会。