As Wang Feng moves to the center of the stage, the lights go dim. He plays a soft melody on the piano, and asks his audience to write down what they see and how they feel.

The second piece that he plays is mostly low-pitched and when he plays the third one, dominated by bass sounds, sobs can be heard in the hall. The last piece is once again a soft melody.

Later, he collects the sheets on which his audience has recorded their observations and feelings, and reads them out.

Wang is demonstrating his Music Therapy at the China Conservatory. As a doctor with the Institute of Acoustics, Chinese Academy of Sciences, he believes music can help psychologists delve into a person's inner world and provide vital clues about mental illnesses.

A 35-year woman records that she is "standing with father in the rain", who leaves when Wang starts the second piece. During the third piece, she sees "the family struggling", and finally feels "life is not that bad".

"It is a typical case of family problems. We see keywords such as 'father', 'family' and 'rain'. This woman may have been hurt by one of her relatives when she was very young," Wang says.

Giving another example, he says a 25-year-old man records seeing "ghosts" when the third piece plays. Unlike most people who feel a sense of tranquility in the finale, this man says he feels "exhausted". Wang's interpretation is that he has experienced some minor hurt that he himself may not be aware of.

"Music therapy can bring out the cause of people's behavior. But it remains only one part of the examination," Wang says.

It can benefit young people by easing their pressures, but Wang also quickly adds that this applies not just to quiet and soft melodies. Heavy-metal, rock, and pop can also help people release negative emotions.

"It teaches people how to handle the pressure, not reduce it," he says.

As a music therapy researcher, Wang says he has to be familiar with a number of genres. "I also have to listen to Jay Chou, whose songs can help me build a good relationship with my patients."

China has at most 10 people who work as music therapists, as the job demands not only music, but also psychological skills. Although the Central Conservatory of Music and China Conservatory have set up a music therapy department, there are no more than 100 people majoring in the discipline around the country.

In contrast, the United States has about 4,000 registered music therapists working in various organizations.

Last September, the country's first music therapy company, Anice, started up in Beijing. It provides mainly online consultations.