Serious consequences, beware of hearing damage caused by headphones.
While modern science and technology bring more fun to our lives, it also inevitably brings some negative effects. As the favorite walkman of the younger generation, it is one of the products. Why do you say that? Please look down.
Recently, when interviewing a college graduate in Guizhou, the examiner said the question three times, but she didn't catch it clearly. As a result, she lost her job opportunity. According to the doctor's diagnosis, the main reason for students' hearing loss is hearing fatigue caused by listening to the walkman for a long time.
At present, there is a popular way to improve English listening quickly on campus, that is, listening to English with a walkman while sleeping. Some students are eager for this. Experts believe that this practice will seriously damage hearing in the long run.
Things that damage hearing like this are very common abroad.
Rock music and walkman hurt your ears.
A few years ago, Peter, a professor of music history at Princeton University, USA. After listening to a rock concert, Dr. Jeffery found that the band's explosive performance made him suffer from tinnitus and insomnia, and his hearing was impaired by 4%. So, Peter took the band to court in a rage.
The Pete case has aroused widespread concern in American society. American medical experts complain that American entertainment shows are getting louder and louder.
1998, a survey published in the Journal of the American Medical Association showed that 15% of adolescents aged 6 to 19 had symptoms of hearing impairment. Experts exclaimed that Americans began to become deaf 20 years earlier than expected, and there were more and more teenagers with hearing impairment. Many people in their forties have the same hearing condition as those in their seventies. Experts believe that the chief culprit of hearing loss is noise.
In addition to noise, walkman is also one of the culprits of hearing loss. In general, the sound can reach the ear after a certain distance, and the high frequency part of the intermediate sound has been absorbed by the air. If you listen to the walkman, the microphone is pressed against your ear, so your ear absorbs all the sound waves, which is very harmful to your hearing.
Using the walkman will also reduce the sensitivity of the ear to sound level perception in the process of adapting to higher sounds. Even if the volume is constant, the listener will feel that the sound is getting smaller and smaller. Therefore, it is easy for listeners to adjust the volume to a degree that may damage their hearing. Therefore, after using the walkman for a long time, you should let your ears rest for a while to avoid hearing fatigue.
It is best not to use a walkman in sports. Because aerobic exercise makes blood flow to the limbs, the inner ear is more susceptible to loud noise. Swedes have done a study to prove that listening to the walkman will double the damage to hearing during aerobic exercise.
Note: I think this may be because the human ear itself has a protective mechanism against sudden loud sounds, but exercise will affect the start of this protective mechanism and cause hearing damage.
How does noise hurt hearing?
When sound enters the ear, it first causes the eardrum to vibrate. Three bones (three ossicles) connected to the tympanic membrane of the middle ear transmit vibration to the cochlea of the inner ear.
The cochlea is filled with fluid, which is connected with hair cells that feel the sound frequency. Hair cells convert vibrations into electronic signals and transmit them to the brain. The cells that feel high-frequency signals are in the outer cochlea, followed by the cells that feel low-frequency signals.
Most people are exposed to dangerous levels of noise every day, but generally for a short time and will not cause hearing damage. Hearing impairment is formed over time. If you are exposed to noise for a long time, even if it is short, it will cause hearing loss.
Musical instruments, like electric drills, may also damage hearing, and both players and listeners must take necessary protective measures. Studies have shown that good music has little damage to hearing, but long-term exposure to high-decibel sounds, whether music or noise, will cause hearing damage. Sensory nerve hearing damage caused by noise occurs in the inner ear. When high-energy sound waves vibrate the fluid in the cochlea, it will be over-stimulated, leading to the death of hair cells.
In this regard, experts vividly made an analogy. When we listen to rock music with the volume as high as 1 10 decibel, if we can take pictures of hair cells, the scene is like a big seed rolling in the wheat field, and hair cells are those poor wheat. When the hair cells responsible for receiving the sound of a certain frequency band are damaged, the sound of that frequency band can not be heard.
Protect your ears.
After people are exposed to high-volume music, there will be a phenomenon of "threshold rise" (auditory threshold rise), that is, the bass that was heard before can't be heard now. Experts suggest that after listening to a lively concert, you should test your listening ability in the following ways: Before listening to the concert, turn the volume of the radio to a position where you can hear clearly. After the concert, turn on the radio and see if you can still hear the sound in that position clearly. If you can't, it means that you have a short-term hearing loss, so you should see a doctor quickly.
When people listen to the walkman in busy streets, the volume is often turned up to cover up the surrounding noise. Therefore, experts advise not to use walkman in the street. If you have to listen, it is recommended to use closed or earphone type.
Experts also suggest that in noisy environments, such as listening to rock concerts, anti-noise earplugs should be worn to prevent hair cells from being damaged. People who often listen to loud music or are exposed to noise should have their hearing checked regularly. If it is a temporary hearing injury, regular examination can ensure that the injured ear can be treated in time.
1 data and methods
1. 1 Clinical data: The subjects were 140 interns, with 280 ears, including 60 males and 80 females, aged 2 1 ~ 25 years, with an average age of 23.7 years. All subjects met the following conditions: 1 no ear history or family history; No history of ototoxic drug treatment; No history of ear injury; No history of otogenic complications and dizziness; The chief complaint is that there is no hearing impairment. Among them, 102 people (experimental group) used earplugs to teach themselves English and listen to radio news, music and other programs. The experimental group was divided into experimental group 1 and experimental group 2 according to the time of using headphones every day. In the experimental group 1, 4 1 person used earplugs and headphones less than 1h every day, and the listening time was 0.60h 0.2 1h, while in the experimental group 2, 6 1 person listened to 1h ~ 2.5h every day, and the listening time was 0. 38 people who didn't use earplugs and headphones served as the control group.
1.2 method: All subjects were tested in a soundproof room. The sound insulation room conforms to the provisions of ISO8253 and is tested according to the test method specified in GB7583-87. Pure tone audiometer is FA- 18 clinical diagnostic audiometer (the instrument has been calibrated at zero level according to GB4854-84). The test frequencies are 250Hz, 500Hz, 1000Hz, 2000Hz, 3000Hz, 4000Hz, 6000Hz and 8000Hz, and the sound intensity level is 2.5dBHL. If the air conduction hearing threshold is above 25dBHL, the bone conduction is increased, and the Weber test of this frequency is conducted again. T test was used in statistical method.
Two results
The results show that the hearing threshold of each frequency band is improved by using earplug headphones, which is significantly different from that without earplug headphones (P < 0.00 1). In addition, the hearing thresholds of short-term users and long-term users are different at all frequencies except 250Hz (P < 0.438+0). Tip: Using earplugs can lead to noise-induced hearing loss.
3 discussion
3. 1 From the table 1, it can be seen that the average air conduction hearing threshold of the experimental group at eight frequencies is higher than that of the control group (P < 0.005438+0). In the experimental group, the hearing threshold in the high frequency region above 4000Hz was significantly higher than that in the low frequency region. The hearing threshold of those who listen to earplug earphone 1h ~ 2.5h is different from that of those who listen to earphone < 1h, except for 250Hz (P < 0.0 1), which shows that the longer the earphone is used, the more serious the hearing damage is.
3.2 Frequent exposure to noise can lead to hearing loss at 4000hz[ 1]. Through observation, it is considered that excessive and non-noise stimulation can also cause cochlear injury and noise-induced hearing loss. The reason may be that after long-term and excessive stimulation of cochlear organs, the metabolism of cell tissue is disordered and the blood supply and oxygen supply are insufficient, which leads to the damage of its peripheral receptors. This set of experiments proves that overstimulation will not only damage the frequency of 4000Hz at first, but also damage other high-frequency areas. The seriousness of the problem lies in that it is the non-verbal frequency zone in the high frequency zone that is damaged, so the injured often have no conscious hearing impairment, which delays the best treatment opportunity [1]. This part of the hearing-impaired people did an ear plugging test in the sound insulation room, and the result showed 13. 2% of people have tinnitus, some have a metal crash, some have a jet sound, and some have a ringtone. The reason why this crowd was not realized in the past may be because of the noisy urban environment. College students are a special group of young people. Because of their heavy academic tasks, they seldom have external entertainment contact and information reception. Under the restriction of school environment, they only rely on earplugs and headphones to receive external information and learn foreign languages, which leads to long-term stimulation of cochlea and hearing loss due to noise. The seriousness of the problem should be highly valued by students, parents, society and relevant education departments.
Although many technical terms are used above, some of them are difficult to understand, but we only need to know one thing: using earplugs does have an impact on our hearing, and it depends on your use time and volume. The higher the level, the greater the impact. Therefore, Bian Xiao has to warn you here, use earplugs carefully and pay attention to the volume!
Children often wear headphones to listen to music, which is harmful to hearing. Because when listening with headphones, the audio is concentrated on the vibrating piece of the small earplug machine, the audio effect received by the eardrum is more concentrated than that of the speaker, and with the ups and downs of music, the spirit is always in a state of tension. At the same time, the distance between the diaphragm and the eardrum of the earplug machine is very close, and the sound wave propagation range is small and concentrated, which greatly stimulates the auditory nerve of the eardrum. Wearing headphones for a long time, this kind of bad stimulation will cause head swelling pain, memory loss, insomnia, and even a lingering sound in the ear, affecting normal hearing.
In addition, experts believe that children's eardrums, ossicles in the middle ear and auditory cells in the inner ear are fragile, which will shrink under the stimulation of high notes for a long time, leading to hearing loss. Therefore, stereo music is not suitable for children to listen to often.