The pound;25 billion government subsidy to Northern Rock hits the headlines and we all talk about it. Children’s untreated communication problems cost a similar amount but there are no headlines and nobody talks about it. Yet this is perhaps the biggest hidden menace in the classroom.

About two pupils in every class, 7 per cent, have a developmental language disorder known as Specific Language Impairment (SLI). This affects understanding, talking, reading and writing and is one of the main reasons why many children do not reach their educational potential. Untreated, it can lead to emotional and behavioural problems and even criminal behaviour.

My colleagues and I at University College London have discovered that a system in the brain for processing grammar is defective in some children with SLI, but that they compensate by using a different brain area. They rely on their understanding of the meaning of words to make up for the fact that they lack an intuitive grasp of the relations between words. Until now it has not been clear whether these pupils struggle to process language generally, or whether they have specific problems with grammar. Our findings reveal that, for those with the pure form of SLI, the problem is specifically grammar.

So, how does this research relate to the classroom? The link is made easier by thinking about language as psycholinguists might.

Language is not one system or ability, but many:

- Syntax (grammar): the structural rules combining words into sentences.

- Morphology: the rules combining words or parts of words into new words (such as jump + ed).

- Phonology: the rules combining sounds into words.

- Lexicon (vocabularysemantics): the store of words.

- Pragmatics: involves anticipating the listener’s knowledge and communication needs.

Specific Language Impairment primarily affects syntax, morphology and, for many children, phonology too, whereas dyslexia primarily affects phonology, so there is some overlap between the two disorders.

By the age of three, most children can produce grammatically correct sentences. Furthermore, they intuitively know that “Who did Joe see?” and “Joe saw someone” are fine, but “Who did Joe see someone?” is not; and they understand who is doing what to whom in “Joe was hit by Mark”. Yet these are precisely the kinds of sentence that children with SLI find difficult, even though in other respects they appear to be developing normally.

Our study used delicate sensors resting on the children’s heads to show which brain circuits were active when they were reading. In some children, we found that the brain circuits involved in grammatical processing were missing, while other language circuits in the brain were operating normally and some seemed to be kicking in specially to compensate. This explains how a child could work out the meaning of “the baby was carried by the old man”, using intact semantic word knowledge but be stymied by “the girl was pushed by the boy”, which requires grammatical understanding.

These findings suggest a new way to help such children overcome difficulties in broader education. First, teachers need to understand the problem so that they can target help. Affected children need to know the relationship between non-adjacent words in sentences - between, say, a question word (who, what, which?) and the word that normally occurs after the verb or preposition.

Take the question and answer: “Who did Joe push?” and “Joe pushed Bill”. They need to understand that the “who?” in the first sentence is the same as the “Bill” in the second. You can illustrate this using a diagram with arrows, linking “who” with “Bill” as you change the sentence from question to answer.

To identify these pupils, we have come up with the Grammar and Phonology Screening (Gaps) test; an easy, 10 minute assessment that identifies SLI andor dyslexia.

It is up to the Government to decide whether there should be national screening to identify these children before problems arise. But isn’t the cost to individual children and society too high not to invest time and money in tackling this problem?

Heather van der Lely is professor and director of the UCL Centre for Developmental Language Disorders and Cognitive Neuroscience at University College London www.ucl.ac.ukdldcn

The Gaps test is available from www.dldcn.com, which is not part of UCL. The professional version including forms to test 25 children costs pound;65.

REFERENCES

Tomblin et al, Prevalence of Specific Language Impairment in kindergarten children, Journal of Speech, Language and Hearing Disorders (1997) 40, 1245-1260

Fonteneau, E. and van der Lely, H. Electrical Brain Responses in Language-Impaired Children Reveal Grammar-Specific Deficits (2008) www.plosone.orgarticleinfo:doi10.1371journal.pone.0001832 (available free online)

Van der Lely, H. Domain-Specific Cognitive Systems: Insight from grammatical specific language impairment. Trends in Cognitive Sciences (2005) 9:2, 53-59.