Many of us use headphones during the day to block out outside noise on the way to work, and even at work. But how does this affect our hearing? The question was dealt with by a BBC Future correspondent.
The process is progressing gradually. The guitar in your favorite song starts to sound kind of soft, and you turn up the volume. Dialogue on TV is not audible. You have a hard time understanding what your friends are talking about in a crowded, noisy bar.
Hearing loss is often not a one-off event, but a problem that gets worse over time. Some experts believe that the premature degradation of our hearing organs is brought closer by modern lifestyles – for example, the increasing use of headphones for listening to music and watching videos. Moreover, the younger generation nowadays suffers much more than before.
Why bother with hearing at all?
“It’s amazing how many events and phenomena in our life can be accompanied by loud noise, and so that a person does not think about it or does not even realize it – until it’s too late,” says clinical audiologist Jill Grunwald from the medical center. – There is a lot of entertainment noise around us: personal players, concerts, bars, cinemas can be very loud.
Grunwald, who lectures on the threat of hearing loss at the Vanderbilt School of Music, explains that excessive exposure to loud noises is a risk factor for everyone, regardless of age, and can lead to noise-induced hearing loss. For Nashville, a city that provides many opportunities for listening to music, including very loud music, this is very relevant.
“Sometimes the effect of noise in a young age does not manifest itself, but, overlapping with age, it begins to have an effect,” Grunwald emphasizes. “Perhaps people think like this:” Well, think, I lost a little hearing, caused him a little damage. “But the problem it only becomes later. ”
What noises are harmful to hearing?
The sounds of heavy traffic from the car are heard at about this volume.
Prolonged exposure to louder environments undoubtedly increases the risk of hearing loss over time. Hearing loss can occur immediately, but very often the symptoms do not manifest themselves for many years.
A study from the University of Leicester in Britain found that many music player headphones are capable of producing a sound pressure of 120 decibels. This is extremely dangerous because noise exceeding 110 decibels “deprives nerve cells of the myelin sheath, making it difficult for the transmission of electrical signals from the ears to the brain.” If you do this damage to your hearing, it will be permanent and irreversible.
“Chainsaw, jet ski – about 100 decibels. 105 decibels. A very powerful audio system in a car can reach 120 decibels or even more. If you are within a meter from a firearm – it is 140 decibels, about this level or even slightly below the pain threshold. ”
Many people have experienced a temporary displacement of the hearing threshold, when after a loud concert or club, hearing acuity drops for several days, but then returns. This happens as a result of a chemical process by which the auditory organs protect themselves – the sounds lose their clarity, because the tiny hairs in the inner ear are overworked.
To recover, try to be in a quiet place until hearing returns and try to avoid this shift in the future.
Now the vast majority of vaccines that are used in the world are whole virion. This type of vaccine has a 300-year history of use. They are well studied – we all know about the peculiarities of their effect on the human immune system, and the understanding of possible undesirable phenomena is tied to this. This is one side. And the second is economic and technological. Our institute has been developing and manufacturing whole virion vaccines for over 60 years. Accordingly, we have all the technological capabilities for such production.
Now many foreign companies and our Russian developers have taken the path of creating new vaccines using genetic engineering methods. Before the pandemic, such startups were of more scientific interest.
Yes, and this is the only example of such a development so far. Until now, there have been no mRNA vaccines at all. But when the world was faced with a pandemic, a powerful impetus was given to the development of this direction – to move to the next level of vaccinology. A lot of money has been invested in such projects, alliances of start-up companies with large biotechnology companies began to arise in order to ensure the production of the required number of doses. This is a very promising direction, but new, and like any new one, not devoid of certain risks.
I am absolutely sure that, perhaps, a year will pass, and the WHO will introduce standards for vaccination against coronavirus, and certify new types of vaccines. Some of the new approaches will be chosen, but with respect to others they will decide that the time is not yet.