"Too early birth is associated with changes in brain development and a reduced brain volume, " explain Julia Jäkel of the Ruhr University Bochum and her colleagues. Previous studies have shown that this also has consequences for the mental development of children: they often show deficits in learning and spatial memory and perform worse when it comes to processing different stimuli at the same time. What these problems are but exactly attributed and how these children could best promote, remained unclear.
"Dramatically increasing deficits"
In their study, Jäkel and her colleagues have tested a hypothesis according to which the bottleneck in premature babies is above all in working memory: if it receives too many tasks and information at once, it is quickly exhausted and the children can not absorb everything. The researchers tested this hypothesis on 1, 326 children at the age of eight, born between the 23rd and 41st week of pregnancy. All children completed a series of standardized tests of their mental abilities. The tasks came from different areas from math to visual tests to verbal tasks. At the same time, the researchers classified the tasks into three stress classes: complex tasks, which had to pay attention to several sources of information at the same time and therefore stressed the working memory, as well as medium and less demanding tasks. display
The result: the higher the cognitive load was, the more clearly deficits appeared in the former preemies. In the light tasks, there was little difference between them and the later born. But if the tasks were accompanied by a high load on working memory, the premature babies were quickly overwhelmed. This also explains why previous studies sometimes yielded contradictory results: The tasks often did not separately record and evaluate the burden on working memory. "The performance deficits of children increase dramatically the sooner they were born and the greater the cognitive burden, " says Jäkel. Infants born prematurely were particularly affected if they were born before the 34th week of pregnancy.
Challenge for the school system
A possible explanation for the lower recording capacity of the preemies already have the researchers: It is known that the networks in the brain gradually adapt under high load by growing and creating more connections. Studies show that this process is more pronounced in premature babies - the brain is virtually recovering from the lost growth in the womb. "This speaks for the plasticity of the brain, but meanwhile leads to losses in the current performance, " explain Jäkel and her colleagues. Concretely, for the children this means that they can make up for their deficits in the course of childhood - but they are more likely to be overstrained in normal lessons if they become more complex.
"As the number of premature births increases, the need for special support in the classroom will increase - a challenge for the school system, " says Jäkel. In their opinion, premature babies could be specifically helped by, for example, equalizing learning content for them and presenting the information contained in them sequentially and more slowly, rather than simultaneously. Studies also show that one can specifically improve the working memory with special computer training. If one adapts to school instruction or support courses, then, despite cognitive restrictions, preterm children can achieve learning success, the researchers conclude.Julia J kel (Ruhr-University Bochum) et al., PLOS ONE, doi: 10.1371 / journal.pone.0065219 wissenschaft.de - === Nadja Podbregar