Scientists have long recognized that children who can best process various aspects of the sounds of language are more likely to read earlier and develop into better readers and writers than those who cannot. After a decade of research, Northwestern Professor Nina Kraus and her colleagues have discovered a subset of learning disabilities that results from a dysfunction in the way the brainstem encodes certain basic sounds of speech.
In an article in the April "Trends in Neurosciences," Kraus, who is Hugh Knowles Professor of Communication Sciences and Neurobiology, and senior research analyst Trent Nicol for the first time ever have linked the source-filter model of acoustics with the cerebral cortex's "what" and "where" pathways via the auditory brainstem.
The research they present in "Trends" represents the theoretical underpinning for BioMAP, the simple neurophysiological test that can identify children with sound processing disorders. Kraus's laboratory, in partnership with Bio Systems Corp., will soon make the diagnostic tool available in the marketplace.
BioMAP objectively measures whether a child's nervous system can accurately translate a sound wave into a brain wave. If it cannot, the affected individual -- like nearly a third of the language-disordered children Kraus has studied -- demonstrates problems in discriminating speech sounds that interfere with normal learning. Once identified, children with these problems will be able to improve their speech discrimination skills through auditory training.