MentalFloss.com: Researchers from Carleton University, Colorado State University, and Michigan State University teamed up with the National Park Service to analyze 18 previous studies on how natural soundscapes can affect human health. Their results, published in Proceedings of the National Academy of Sciences, suggest that listening to nature-made noise may decrease pain and stress, improve cognitive function and mood, and more. The research even sheds light on what sounds might bring about specific benefits; soundscapes that included birds, for example, had the largest effect on lowering stress and annoyance.

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