Grammar is a complex human ability yet by the age of three most children can make grammatically correct sentences. Kids with a specific language impairment(SLI), however, continue to make grammatical errors, sometimes even into adulthood. As teenagers they might make errors that other children rarely make after age five; for example, when asking a question they might say “Who Joe see someone?” rather than “Who did Joe see?”.

SLI affects about seven percent of children and is a major cause of children not reaching their educational potential but it's never been clear if these children struggle to process language or just grammar.

Researchers at University College London may have some answers. They have discovered that a system in the brain for processing grammar is impaired in some children with SLI but that these children compensate with a different brain area.

In the UCL study they took electrophysiological brain measurements of children with SLI. The results showed normal responses for a variety of language tasks but a specific deficit in brain circuitry involved in grammatical processing. The study also found that the G-SLI children appeared to be partially compensating by using neural circuitry associated with vocabulary/word meaning or world knowledge (semantic processing). For example, a child could work out the meaning of “The baby was carried by the old man” but not “The girl was pushed by the boy.” The latter sentence requires knowledge of grammar to understand who is doing what to whom.

Professor Heather van der Lely, Director of the UCL Centre for Developmental Language Disorders & Cognitive Neuroscience, says: “Specific language impairment is not as well known as autism, yet the disorder affects seven times as many children, and prevents them reaching their potential.

“We have discovered that a number of these children have specific problems with grammar, reflected in our measurements of a circuit in the brain which appears to be uniquely involved in grammar. G-SLI children with a deficit here appear to be compensating by harnessing another brain area involved in general word processing. Not only does this offer an intriguing insight into how such children may be coping with language, but it suggests a new way is needed to help them to overcome their difficulties in broader education.

“Government departments are starting to recognise the problem, but we need more resources. Our results suggest that enhanced general language teaching is unlikely to help – these children need focussed and specialised help. It is not a question of giving these children more of the same, but re-directing them to use the skills they do have to understand and communicate. Surprisingly, only a handful of experts in the world are conducting brain research into children with SLI.”

Funded by the Wellcome Trust.

Article: Fonteneau E, van der Lely HKJ (2008), Electrical brain responses in language-impaired children reveal grammar-specific deficits, PLoS ONE 3(3): e1832. doi:10.1371/journal.pone.0001832