New study shows the stress-relieving effects from nature sounds are minimal when there’s traffic noise mixed in
There’s a mental health treatment happening right outside your window – if you can hear it over the traffic. Scientists have quantified what bird enthusiasts have long suspected: natural soundscapes can significantly reduce stress and anxiety, but only when they’re not competing with the roar of rapid transit.
The research, conducted by scientists at the University of the West of England, comes at a crucial time when cities worldwide are debating the merits of reducing speed limits. While these discussions typically center around safety concerns, this study suggests that slower traffic speeds could offer an unexpected benefit: allowing urban dwellers to better experience the therapeutic effects of nature’s symphony.
The study’s findings paint a clear picture: when people can hear natural sounds without the interference of high-speed traffic noise, they experience lower levels of stress and anxiety. However, this calming effect diminishes as traffic speeds – and their accompanying noise levels – increase. It’s like trying to appreciate a Mozart symphony while someone runs a vacuum cleaner; the underlying beauty gets lost in the mechanical cacophony.
The research team recruited 68 university students for their experiment, carefully designing a series of tests to measure how different soundscapes affected participants’ mood and stress levels. Each participant went through three rounds of exposure to different sound combinations: pure natural sounds, natural sounds mixed with 20 mph traffic noise, and natural sounds combined with 40 mph traffic noise.
Lowering the speed limit in cities could also lower the sound of traffic, which could effectively lower stress levels for residents. To ensure the results weren’t simply reflecting participants’ natural mood fluctuations, the researchers first exposed them to stress-inducing stimuli – think complicated math problems presented with flashing colors and irritating background noises.
Natural soundscapes alone proved most effective at reducing stress and anxiety, with participants reporting their lowest stress levels after listening to pure nature sounds. When 20 mph traffic noise was added to the mix, the calming effects were somewhat diminished but still present. However, when the faster 40 mph traffic noise was introduced, the therapeutic benefits of nature sounds were significantly masked, leading to higher reported levels of stress and anxiety.
While cities have traditionally focused on creating green spaces, this research suggests that these areas need to be acoustically protected as well. It’s not enough to plant trees and hope for the best; we need to consider how traffic noise might be preventing people from fully experiencing the mental health benefits these natural spaces could offer.
The study’s results are particularly relevant for individuals who already struggle with anxiety. The researchers found that participants with higher baseline anxiety levels were more sensitive to the negative effects of traffic noise, suggesting that reducing urban noise pollution could be especially beneficial for those most vulnerable to stress-related mental health issues.
Implementing lower speed limits in urban areas could create what might be called “acoustic sanctuaries” – spaces where natural sounds can prevail over the mechanical chorus of city life. This aligns with a growing movement in urban planning that advocates for “20-minute cities,” where most daily needs can be met within a 20-minute walk from home, naturally encouraging slower traffic speeds.
The future of urban soundscapes might also be shaped by technological advances. The researchers note that the widespread adoption of electric vehicles could help create quieter urban environments where natural sounds can better penetrate. Combined with thoughtful urban planning that integrates green spaces along transit routes, cities could become not just more sustainable, but more sonically soothing as well.
Ultimately, findings like these become ever more crucial as our world becomes increasingly urbanized. They remind us that in our rush to build bigger, faster cities, we might be drowning out one of nature’s most potent medicines: its soundtrack.
