Natural hearing loss caused by age.Many elderly people will have some hearing loss.This is the result of the automatic decline of bodily functions when people get older.Exposure to high frequency noise environment for a long time.For example, working in a high-frequency noise environment, such as wearing headphones for a long time to listen to music with loud sounds, or deafness caused by some drugs, can also cause hearing loss from the beginning.
Normal people’s hearing is generally between -XNUMX and XNUMX decibels.Hearing functions are normal.
The hearing of patients with severe hearing loss is already greater than XNUMX decibels.In patients with severe hearing loss, in addition to severe hearing impairment during communication, their speech will also become blurred.At this time, the effect of wearing a hearing aid depends on the frequency and degree of the patient’s residual hearing.Because the patient’s speech recognition ability is very poor, in addition to relying on hearing aids, they have to rely on their visual observation and even touch to perceive sound.
人的耳朵并不能听到宇宙间的一切声音，有一定的范围，平均是20-20000赫。人们的听觉主要用来听语言，而语言的频率并不宽，其主要范围是在500-3000赫。因此，科学家把500赫、1000赫、2000赫这3个代表性频率叫做语言频率。听力的计算，便是用这3个音频检查所得分贝数加起来除以3，所得平均数就是人耳的听力水平。
