Due to a rare form of hearing loss, a woman cannot hear men’s voices

In a scene straight out of a mystery thriller, a woman in Xiamen, China, woke up in a hospital one day to find that she could no longer hear her boyfriend’s voice. Not just her boyfriend’s voice, she could no longer hear men’s voices at all. What shocked her even more was the fact that she could still hear women’s voices perfectly fine. She was later diagnosed with a rare ear disease called Reverse Slope Hearing Loss (RSHL), Daily Mail reported.

The woman, identified only by her surname “Chen,” said she heard a strange ringing in her ears the night before that morning and also felt nauseous. When she could no longer hear her boyfriend’s voice, she visited an ear, nose and throat doctor at Qianpu Hospital, where she was told she was suffering from the rare disease. Dr. Lin Xiaoqing, the doctor who treated her, said Chen could hear her when she spoke, but could not hear a man. “She couldn’t hear him at all,” Dr. Xiaoqing said.

RSHL refers to an ear condition in which a person’s ability to hear low-frequency sounds is impaired. According to AanviiHearing, these low-frequency sounds can include men’s voices, bass notes in music, and rumbling noises like thunder. On an audiogram, a chart audiologists use to measure hearing levels, RSHL appears as a downward slope from low to high frequencies. Low-frequency hearing loss is less common than high-frequency hearing loss, which has an upward slope on the audiogram. According to Audiology & Hearing, only one person in every 12,000 cases of hearing loss has RSHL.

Normally, a person hears a sound when sound waves enter the outer ear and travel through a narrow passage called the ear canal, which leads to the eardrum, according to the National Institute on Deafness and Communications Disorders (NIDCD). Then the eardrum vibrates and sends those vibrations to three tiny bones in the middle ear, the malleus, anvil and stapes. After these bones amplify these sound vibrations, they pass them on to the cochlea, a snail- or spiral-shaped structure filled with fluid, in the inner ear.

When the vibrations reach the cochlea, the fluid within it is agitated, creating waves. These waves cause the hair cells to move up and down. This triggers chemical reactions and results in electrical signals that are sent to the brain, informing it of the sound the person is hearing. Therefore, the frequency of hearing loss depends on which part of a person’s ear is affected.

Speaking to Business Insider, Patricia Johnson, an audiology doctor, explained that there are three main causes of RSHL. First, “A certain gene could cause certain hair cells to never develop in the womb,” Johnson said. These tiny hairs are crucial for a person to detect different pitches. Second, RSHL can also be the result of another ear condition, such as Meniere’s disease, which affects the fluid around the hair cells, Johnson added. Apart from that, the condition could be triggered abruptly, as in Chen’s case, most likely due to a viral infection. However, Chen’s RSHL, doctors believe, was caused by stress, overwork, and lack of sleep. They also confirmed that recovery is possible in her case.