A common childhood language disorder stems from a brain-based difficulty in discerning the acoustic building blocks of spoken words, especially in noisy settings such as classrooms, a new study suggests.
Researchers estimate that as many as 7 percent of U.S. elementary school students experience substantial problems in understanding what others say and in speaking comprehensibly, despite good physical health, normal hearing, and average-or-better intelligence. The precise grammatical failures of children with this condition, known as specific language impairment (SLI), remain controversial.
Psychologist Johannes C. Ziegler of the University of Provence in Marseille, France, and his colleagues find that these children's subtle problems in identifying spoken consonants in quiet settings become far worse with the addition of background noise.
In kids free of language problems and in youngsters with SLI, constant background noise disrupted consonant detection more tha