These are feverish days. The Christmas shopping rush, the happy birthday aperitifs, the chaos of the centre. With cars, public transport and two-wheeled vehicles queuing up. Well, in these circumstances there are not only the risks associated with traffic fumes. We must not forget hornskids and more, which they create artificial sounds. And they can become cause of stress.
But if you know that over time noise puts you at risk not only the ear but also the heart and vesselsnow research shows how “human” sounds linked to vehicular traffic can even “turn off” the advantages of staying in nature, in the greenery, with the birds singing. These natural sound elements they have been shown to work as an anti-stress, favoring a decrease in blood pressure, breathing patterns, heartbeats, as well as calming stress and anxiety. The study appeared on Plos One and was led by Paul Lintott of the University of the West of England and Lia Gilmour of the Bat Conservation Trust.
What the study says
The research involved 68 student volunteers who listened to three 3-minute soundscapes: a natural soundscape recorded at dawn in West Sussex, UK, the same soundscape combined with sounds of road traffic at 20 miles per hour, and the same soundscape with 40 mph traffic sounds. Mood and anxiety were assessed before and after the sound stimulations.
It turned out that listen to a natural soundscape reduced self-reported levels of stress and anxiety and also improved mood recovery after a stressor. But be careful: the psychological benefits associated with nature are reduced in the presence of traffic sounds.
Future prospects? Reducing traffic speed in urban areas could influence health and well-being by acting on safety and, above all for these objectives, by acting positively on sound environments.
How much noise affects well-being
A fact for everyone. Exposure to noises above 90 decibels for eight hours a day, in practice a threshold that defines loud noise such as the siren of a passing ambulance, can induce over the years a permanent hearing loss.
Furthermore, if you live in a particularly noisy area, hearing pollution can interfere with the quality of sleep and can also lead to alterations in blood circulation, increasing the dangers to heart health.
In this era of sounds that persecute us, therefore, it slowly becomes more difficult to hear the voices of those around us, or we always have to turn up the volume on the television to follow our favorite programme. These are some of the signs of presbycusisan almost physiological problem but certainly accentuated by the noise of daily life, which is of interest today one in three people over sixty and is concentrated especially among males.
For all these individuals, it changes what the experts call comfortable audibility level (between 50 and 65 decibels), which corresponds to the intensity of normal conversational voice. And whoever speaks to us must increase the volume to be heard.
The effects of noise on stress and the heart
Noise pollution may synergize with air pollution in mediating an increase in risk of atherosclerosis and cardiovascular disease. Traffic noise can activate a stress response chain reaction involving the hypothalamus, limbic system and autonomic nervous system. This leads to the activation of the hypothalamic-pituitary-adrenal axis and the adrenal sympathetic-medullary axis, leading to a increased heart rate and stress hormone levelsone greater platelet reactivity, vascular inflammation And oxidative stress.
In short, the noise hurts the heart. And it combines with what happens to the respiratory tract. One of the keys to these phenomena would be to be found in the amygdala, which is basically a sort of brain “camera” that activates and modulates responses. Right through the amygdala the signals that lead to vascular inflammation and consequent pathology of the heart and arteries would pass in response to high exposures of noise pollution.
A recent study reported that combined exposure to air and noise pollution is significantly associated with a greater risk of cardiovascular events compared to exposure to only one of these two external elements or to none of them, precisely because of the different degree of inflammation of the arteries.
The negative effects of traffic noise are much more significant at night, likely due to disruptions in the sleep-wake cycle, sleep deprivation, and/or fragmentation and disruption of time periods critical for physiological and mental recovery. In short: let’s pay attention to noises. It is not for nothing that the World Health Organization (WHO) has reported a increase in psychological disordersranging from mild to severe, due to the constant stress caused by exposure to urban noise.
