HEARING OF YOUNG JAPANESE DECLINE DUE TO PORTABLE MUSIC DEVICES

The hearing abilities of younger Japanese people aged in their 40s or under have progressively gotten worse since the beginning of the millennium, according to a major study conducted by a team including researchers at Keio University, Ryo Watanabe reported for Mainichi Japan late on March 26, 2021.

The team published its findings of the analytical study -- one of the largest of its kind in the world -- in the British medical journal The Lancet Regional Health. Generally, there is a decline in an individual's ability to hear as they age, but the hearing capabilities of examined subjects deteriorated so much over 20 years that one age group recorded hearing levels equivalent to those normally experienced among individuals up to 20 years older than them.

The World Health Organization (WHO) has stated that people are at risk of hearing loss due to unsafe listening habits, and has warned of hearing damage stemming from widespread usage of portable music players. However, the actual nature of hearing damage among young people had previously been unknown.

Hearing statistics for some 30,000 individuals were collected from 2000 to 2020 at the Tokyo Medical Center, based in the capital's Meguro Ward, and the team analyzed data of 10,681 subjects aged between 10 and 99 -- excluding individuals whose hearing was impaired due to ear-related disorders. The subjects' ability to hear was assessed by testing their auditory sensitivity of pitch and loudness by combining frequencies ranging from 125 to 8,000 hertz with sound levels measuring from 0 to 110 decibels.

The research found that individuals of both sexes aged in their 40s or younger tended to have increased difficulty in hearing high-pitched sounds of 4,000 hertz. Tests conducted between 2016 and 2020 revealed that these individuals found it hard to hear sounds unless they were louder by 0.8 to 2.4 decibels compared to sound levels required in the period from 2000 to 2004.

In terms of hearing age, the group that saw the biggest deterioration in hearing was women in their 20s, who had a hearing age 20 years older than their actual age. In other words, it can be said that women in their 20s between 2016 and 2020 had the same hearing abilities as women in their 40s between 2000 and 2004.

WEEKLY FEATURE : BONNER DYTOC SHOWS THE WAY IN STOCK PLAY