Japanese health officials are attempting to deal with a growing problem—a million young adults, mostly men, have locked themselves in their bedrooms and are refusing to come out. This condition, called “hikikomori” by Japanese health professionals, is deeply troubling Japanese leaders.

Those suffering from hikikomori tend to sleep during the day, and at night they surf the Internet.

“Our play has changed, it’s all on screens and not real-life situations any more. There are cultural reasons also, a strong sense of embarrassment and an emotional dependence on the mother,” Dr. Takahiro Kato, a researcher studying the phenomenon, said.

“Once you experience it, you lose reality. I knew it was abnormal, but I didn’t want to change,” Yuto Onishi, 18, said. He went through a stage of hikikomori during the years he should have been in high school.

According to some researchers, hikikomori is triggered by the high expectations of Japanese parents and society.

Onishi, for instance, failed as a class leader in junior high school and withdrew from society to avoid his shame and the judgement of others.

“There are cultural reasons [for hikikomori], too,” Dr. Kato explained. “A strong sense of embarrassment and an emotional dependence on the mother.”

Kato’s research focuses on the aspects of hikikomori that cannot be attributed to mental illness.

He has found that the only way to end hikikomori is to have patients confront the trauma which makes them want to withdraw from the world.

Japanese culture is currently facing a massive shift away from traditional preconceptions about sexual relationships and society.

In 2013, 33 percent of Japanese adults surveyed said that they believe marriage is pointless.

A phenomenon the Japanese call “sekkusu shinai skokugun”—celibacy syndrome—is sweeping the nation. Nearly half of respondents to a 2015 survey in the country told researchers that they haven’t had sex in the last month and are actually disinterested in it.

This is a five percent increase from a survey from 2014.

That survey also reported that nearly a quarter of Japanese youth have no interest whatsoever in a romantic relationship.

Some sex experts in the country are going so far as to call this trend a “flight from human intimacy.”

All of this compounds into what some call a “demographic time bomb.” Japan’s population is steadily shrinking, with the birth rate in 2014 being nearly 300,000 births less than the death rate.

If Japanese population decline continues as it is now, there could be disastrous effects for the Japanese economy.