Touching Lives - June 2005
Speech and language in children born preterm
Ten thousand children a year are born this early, and of those ten to 15 percent develop major neurological impairments. A further 20 to 30 percent will have difficulties with behaviour or learning, including reading or understanding speech or grammar. Dr Torsten Baldeweg believes this is the result of injury to the immature brain. “They may have suffered lesions which are the result of bleeding into the brain, or loss of oxygen,” explains Dr Baldeweg.
Remember Hercule Poirot’s “little grey cells”? Neuroscientists do indeed divide the brain into “white matter” and “grey matter”. White matter, with which this study is concerned, consists of the nerve fibres which send messages to the body to carry out tasks, from the simplest such as lifting an arm, to the most complex articulation of speech. Thanks to modern scanning techniques, these nerve fibres can be tracked to very precise areas of the brain.
^The team at University College London, led by Dr Baldeweg, is hoping to recruit some 60 children, aged ten or so, from a pre-existing sample of 4,000.^ These children have previously been monitored, at the ages of two and eight, by team members Professor John Wyatt and Dr Brigitte Vollmer, but Dr Baldeweg is planning a more extensive investigation this time.
He will use two scans. The first uses radio frequency waves inside a magnetic field to map the structure of the brain, in particular the white matter fibre tracts which connect the different parts.The second scan measures blood flow and blood movement within the brain. It’s called a ‘functional’ scan, because subjects are asked to carry out activities — here perhaps listening to or forming speech — while the scan is in progress to highlight the areas of the brain used during the exercise of that function.
Making a switch
Dr Baldeweg is fascinated by the immense plasticity and resilience of a child’s brain, and its ability to compensate for damage by switching functions to different parts of the brain, or from the left to the right hand side. He thinks that by the age of ten these changes will be apparent. The scans will identify where and what the damage was, and how the brain is exercising the recovered function.
An interesting aspect of the project is that it is multi-disciplinary, involving both neurologists and experts in speech therapy.
“It’s still a mystery why some children recover functions, while others struggle,” says Dr Baldeweg.”We are looking to find out whether this is something systematic, and whether there are other factors at work which need further research.We hope that in a few years we will have accurate diagnostic tools such that we can identify through scans the newly born infants who have suffered this kind of damage, and offer counselling and speech therapy, for example, much earlier than we do at present.”
Grateful thanks to the Garfield Weston Foundation for funding this research.