Reading and Language in Children
- Reading and language impairments: Our research focuses on phonology and speech perception in childhood-based reading impairments. We
are also interested in how children with reading problems have difficulties with spoken language, such as poor grammatical morphology and sentence
- Neuroimaging studies : Studies with children include functional Magnetic Resonance Imaging (fMRI) and event-related
potentials (ERPs), which we use to record brain activity as children read or listen to words or sentences. These studies allow us to
investigate how different brain regions are implicated in children's reading and language disorders. For example, in a current study we are using both ERP and fMRI to measure brain activity while children match a word that they hear to a picture on the screen.
- Genetics of language and reading disorders: We are currently undertaking a genetic linkage study in collaboration with other Canadian researchers. In this study, we are collecting DNA from families of children with varying reading abilities. Genetics samples are collected using buccal swabs. This information is being used to identify potential genetic factors implicated in different aspects of reading and language abilities.
Language Processing in Adults
- Working memory and language comprehension: A series of studies are investigating
whether listeners with different working memory capacities, as measured
by standard tests of verbal working memory, differ in their processing
of spoken language. We are interested in whether performance is affected by concurrent
tasks that increase memory load or interfere with perceptual processes. We are also interested in whether memory loads interfere with processing nonverbal spatial information.
and derivational morphology . These studies
focus on how listeners process grammatically complex words such as "walked"
and "runner." For instance, we are interested in the different cognitive
and brain mechanisms that are involved in recognizing and producing regular
and irregular morphological patterns (bake-baked, vs. take-took). Processing is measured using reaction times in a lexical decision task, and also using ERP and fMRI to identify neural responses to morphologically complex stimuli.
- Neurobiology of Reading Proficiency These studies investigate whether the variability in reading proficiency observed in normally reading individuals relates to differential activation of the neural network for language. We are also using diffusion tensor imaging, DTI, to determine whether the variability observed in reading proficiency in normal readers relates to differences in the morphology and coherence of the pathways that connect the language centers of the brain together.
- Neural Bases of Dynamic Auditory Perception We are using fMRI to examine auditory cortical responses to fundamental characteristics of auditory stimuli. Speech is a complex acoustic signal built up of simpler acoustic features. We are interested in how areas of auditory cortex respond to these basic features.
- Speech Perception and Reading in Chinese This research involves examining neural activation for language and auditory processing in Mandarin Chinese and English speakers. Specifically, we are using fMRI to look for potential differences in the processing of tonal information to denote different words in Mandarin, and how this differs from the mechanisms that allow listeners to discriminate speech categories like vowels or consonants.
- Neuroimaging of Language Processing in Bilingual Speakers: This research is examining the relationship between neural processing and proficiency and age of acquisition in second language speakers.
Current Grant Support
Canadian Institutes for Health Research
Operating Grant: "Neural bases of normal and impaired speech perception in children and adultss
New Investigators Program: "The Neural Bases of specific language impairments and dyslexia: Evidence from neuroimaging" 2005-2008