Liu Xianghang chats up a storm online, but when it comes to real people, she has a fear of communicating.
"Talking with others in the real world always makes me blush and my heart beats quickly. I never dare to look in anyone's eyes when speaking," the 22-year-old said, describing her anxiety.
"But I become quite a different person on the Internet. I can chat with anyone and say anything I like, which makes me very popular among netizens," Liu added.
Liu has the classic symptoms of social anxiety disorder, Wang Xumei, a psychologist at Shengjing Hospital of China Medical University, told China Daily.
According to Wang, the number of social phobia patients he is seeing is nearly 50 percent more than in each of the past 10 years.
China News Week reported in 2011 that social anxiety has been rising in China, with 10 percent of people experiencing distress in social communication.
According to the Social Phobia/Social Anxiety Association, a non-profit organization in the United States, about 7 percent of the world's population has some form of social anxiety disorder.
Liu, a senior at Northeastern University, is looking for job, but her social phobia has led to many rejections.
For several years, her spare time has been spent online. If she's not near a computer, she reads e-books on her mobile phone, rather than chatting with classmates or even friends.
"I don't know what to say to them. I feel relaxed on the Internet. We don't know each other online, so I feel free to talk about anything."
Liu saw a psychologist at her school, but that didn't help. She even bought books on conversational skills. "Useless. I've read them all and still don't know how to start a conversation."
"It's caused by a sense of inferiority," said Wang.
The Internet worsens the situation because virtual networks degrade people's communicating ability, she added.
Students are not the only group with the problem: Many white-collar workers find themselves tonguetied around real people as well.
Huang Xueqi, an employee of an exhibition company in Shenyang, capital of Liaoning province, uses MSN to chat with a colleague sitting opposite her rather than talking face to face.
"I'm used to that. Many of my colleagues do the same. I know it's unusual, but I can't break away."
This behavior drives employers crazy.
"Communicating online is convenient and efficient. But it's harmful for the cohesion of an enterprise because it's easy to misunderstand.
"Face to face is more accurate because you can judge by tone or body language," said Zhang Haiquan, head of a promotional company in Shenzhen, Guangdong province.
To get his employees talking more, he often organizes dinner parties. He even put up a wall-sized memo reminding his staff: "It's time to talk with your colleagues."
Wang said people with social phobias should minimize their use of online chat tools and try to find pleasure in face-to-face communication.
People with severe symptoms should seek help from psychotherapists, Wang said.