Final answer:
Without the specific details of the Lund University study, it is impossible to say exactly why the researchers might disagree with a blog writer's assumptions about the benefits of learning Russian.
Step-by-step explanation:
Based on the provided text snippets, there is not enough information to definitively determine why the researchers at Lund University would disagree with the blog writer’s assumptions about the benefits of learning Russian. However, there are general research findings from various studies related to language learning and cognition that may be relevant.
For example, research by Johns Hopkins University found that bilingual education has beneficial effects, suggesting a complexity in language learning beyond simply learning vocabulary and grammar. Also, John A. Lucy's work indicates that the structure of a language can influence behavior and even factory safety. John Schumann's research in applied linguistics, particularly the acculturation model, suggests that social factors play a significant role in language learning. These cumulative studies hint that there is a multifaceted relationship between language learning and cognitive function, and the assumptions about the benefits may not be straightforward.
The Sapir-Whorf hypothesis, which suggests that the structure of a language affects its speakers' world view and cognition, is another relevant aspect of this discussion. Researchers like Lera Boroditsky have written about the influence of language on thought, indicating that the topic is complex and still under investigation. Without direct details on the Lund University study, we cannot accurately depict their stance on the blog writer's assumptions, but we can gather that many researchers find the relationship between language learning and cognition to be nuanced and multidimensional.