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Marie was born with a severe heart defect. Her left ventricle was too small, which greatly restricted two of the heart valves, so the heart couldn’t work properly. As a result, Marie had to undergo an operation at the University Children’s Hospital Zurich shortly after birth. Operations on children’s hearts are particularly challenging because a newborn’s heart measures just two centimeters – about the size of a damson.
In Switzerland, some 30,000 adults live with congenital heart defects, with the majority experiencing only mild symptoms, if any. Severe heart defects like Marie’s, on the other hand, are rarer. Out of 80,000 births in one year, one in 100 children is affected by a heart defect. Between 200 and 300 children are born with a severe heart defect.
Marie is now 10 years old. Her parents often have cause to worry. Even after she survived the operation, they still faced anxiety about whether she would develop normally. Under strict instructions not to overexert herself, she was nevertheless supposed to enjoy a happy childhood. At kindergarten and during the first two years of school, Marie was able to keep up. But problems started to arise by the time she reached her third year. Marie was unable to plan her work very well, her memory was poorer and she worked more slowly than her fellow pupils.
“These executive functions have nothing to do with IQ,” explains Bea Latal, developmental pediatrician at the University Children’s Hospital Zurich. “The control and regulation processes that enable someone to think and act quickly, appropriately and with a sense of purpose are either not yet fully developed or are impaired in children born with serious heart defects.”
Bea Latal should know. Over the past 10 years, she has been collaborating with the Department of Cardiology to scientifically monitor a cohort of 200 children all born with severe heart defects who were treated at the University Children’s Hospital Zurich. Marie is one of them. Latal studied all the children from birth and collected extensive data on their personal development levels. The children were then examined again at the ages of one, four, six and ten years. Latal reported that the most recent tests revealed a deficit in executive functions in many of the children. While this deficit was of little significance at pre-school age, it would negatively affect their progress in school.
Marie, for example, gets easily distracted. When she is supposed to be completing a class test, she is more interested in what her neighbor is doing or what’s happening outside. Her teacher notes that she struggles to persevere with a task, and is unable to concentrate on her work.
But what are the causes of this? “Previously, developmental delays were put down to the major heart surgery that took place after birth,” explains Latal. “Nowadays, we know this is not the reason. Even during pregnancy, an insufficient supply of oxygen to certain regions of the brain can be detected in the fetus.”
Can anything be done to counter this lack of oxygen? Prenatal measures, such as providing an additional supply of oxygen via the mother during pregnancy, are currently being tested in a first series of clinical studies. Whether they will be successful remains to be seen. That’s why Latal prefers to concentrate on training executive functions.
The 200 children in the cohort she is studying are now 10 years old. Latal sees the period of change associated with the onset of early adolescence as a window of opportunity. Research has shown that the brain of adolescents is highly plastic. So why not use the opportunity to develop the executive functions at this age using targeted exercises?
In a new interdisciplinary study, which has four years of funding from the Swiss National Science Foundation (SNSF), Latal wants to analyze the executive functions of the children in detail as well as improve them. The idea is to measure the progress of brain development by using magnetic resonance imaging of the brain. A program of exercises, yet to be developed, should motivate the children to work on their attentiveness and executive deficits. “At this age, children are especially motivated to participate,” says Latal. That’s because they want to be like their friends.
The methodology for the new developmental support program will be play-based. The Swiss researchers are therefore working with a specialist from the University of California, Berkeley, who designs games to promote executive skills. Fun computer games, for instance, can be used to help improve a child’s ability to concentrate. “The ideal game would be one that could be played in a group with other children,” muses Latal, who is only just embarking on this research.
And Bea Latal would not be Bea Latal if she didn’t also intend to record data on stress behaviors and resilience at the same time. Ultimately, she knows from her thesis supervisor, the renowned developmental pediatrician Remo Largo, that large quantities of data from a sizable cohort offer enormous research potential, and can also be of significance for follow-up projects.
