A migrant worker who seriously injured his wife and 1-year-old son in separate incidents has once again put the spotlight on the lack of psychological support for the nation's floating population.

The 31-year-old man, surnamed Chen, stabbed his wife in her abdomen with a knife during an argument over their children's upbringing. Then, when he came to visit her at Shanghai's Renji Hospital with their 1-year-old son, he severely injured the toddler by throwing him on the floor headfirst.

"The man became out of control when talking on his phone, and he threw the boy to the ground - hard," said a witness surnamed Wu.

Video from the hospital's surveillance camera showed the man was holding the boy on his shoulder while talking on his phone. Then he suddenly threw the child on the floor.

Doctors said the boy suffered a fractured skull and cerebral hemorrhage and was sent to the Shanghai Children's Medical Center for treatment. His condition is said to be stable and there is no immediate danger.

"But it's hard to judge whether there will be any sequels to the incident in the future," said Xia Lin, a member of the medical staff.

The man, who works as a carpenter, was detained on Monday for intentional injury. Police said they are still investigating the case and declined to say more.

However, in a local TV news report his wife said he attacked her after they quarreled about where to raise the children. The man and his wife, who come from Huanggang in Central China's Hubei province, also have two daughters.

"He asked me to take our children back to our hometown. But I don't want to quit my job. I want to work," she said.

The TV news report quoted Chen's mother as saying that the couple had been continually arguing over the past week.

The case has drawn a great deal of attention, and there have been calls for better psychological support for the floating population.

"Migrant workers often have low incomes and poor living conditions and there is huge psychological pressure," said Zhang Qi, deputy director of the psychological counseling center at East China Normal University.

"A majority of migrant workers come from remote rural areas. They are less educated and have no experience of city life. It's difficult for them to adapt to living in a city.

"Faced with an unfamiliar environment and unfamiliar people, almost all of them will feel stress, anxiety, fear and other psychological pressures. These pressures, if not timely eased, will result in more psychological problems and even violence," he said.

There are about 23 million residents in Shanghai, and 40 percent of them are migrant. Among this so-called floating population, many are doing odd jobs and have no stable income.

A survey by the mental health department of Qingdao, Shandong province, in 2011 showed the psychological health of the floating population is lower than any other group and can lead to extreme behaviors.

"Many bigger companies already offer psychological support for their workers. But this is not enough. There needs to be more help from the government and society. So far, there are few psychological support programs provided by government for the migrant population in cities," said Wei Zimin, who provides an employment service for migrant workers.

"There should be more comprehensive and consistent psychological support for this group," he said.