My Project

People are not equally proficient in their language and reading ability. Within the 'normal' population, people vary widely in their language and reading skills, and as many as 15% of otherwise normal children born each year, despite normal exposure to their native language, may fail to acquire normal language and speech (Tallal et al., 1996) or reading and writing (Stein and Walsh, 1997). One hypothesis is that developmental delay in language and reading ability has its root in deficits in more basic perceptual and cognitive processing skills (Farmer and Klein, 1995). The generality of the coexistence of perceptual and language problems in the same individuals both across children diagnosed with developmental language delay, and across the age span in the 'normal' population is not known. The purpose of the present research is to address this question. The research is in two parts. The first phase is a 2 year cross-sectional study of the perceptual and cognitive correlates of language and reading function across the age range from grade schoolers to elderly adults in the general population. This study will identify the basic processing skills which are most highly correlated with language and reading proficiency. The second phase is a longitudinal study. It will take the measures of perceptual/cognitive skills, revealed by the cross-sectional study to be most informative about language/reading function, and use them to follow longitudinally a cohort of grade-school children for 5 to 7 years. This study will provide evidence on the relationships between the developmental trajectories of language function and the basic processing skills thought to underlie it, and this is the most powerful strategy for drawing causal connections between the two levels of function. The research will provide new incidence data on perceptual, cognitive and language skills in the population, and the relations between them. Knowledge of those patterns has direct implications for the remediation of children with developmental language delay, and also for the development of language and reading skills in the general population. This project is coordinated with a related study by Drs Trainor and Shore in the Psychology Department at McMaster University. Those scientists are studying auditory temporal processing in infants, using stimuli comparable to some of those used here. This coordination will provide a more comprehensive description of auditory temporal processing development than has previously been available.