Multi-site Dyslexia Data: Methods for Integrating Existing Datasets

Neuroimaging studies of dyslexia and other complex disorders are often under-powered, in part because of MRI scanning costs and the difficulty of recruiting and carefully selecting participants.  Integrating data from existing studies will increase power and provides the opportunity to use the same analysis methods across samples, but there are significant methodological challenges to the success of this approach.  Our recently initiated NICHD supported project aims to address some of these challenges that include protection of participant identify, behavioral heterogeneity within and between samples of complex disorders, missing data, and the appropriate statistical pooling of data across samples.  Check back soon for more information and please contact us if you would like to contribute to our project (dyslexia AT musc.edu).

A special thanks to Dorothy Bishop for posting information about our project.

Changes in the Brain that Occur with Hearing Loss

Age-related hearing loss occurs for just about everyone.  We wondered about the potential impact of hearing loss on brain structure because speech recognition can be difficult even after correcting for poor hearing thresholds.  In a sample of 49 older adults, we observed that high frequency hearing loss was associated with lower gray matter volume in [...]

Missingness in fMRI Studies: Multiple Imputation

Limited imaging coverage of the brain and susceptibility artifact contributes to missing data in functional imaging studies.  Multiple imputation is one solution for dealing with missing data.  We demonstrate in a recent Neuroimage manuscript the considerable benefit of using multiple imputation in functional imaging studies. There was a 35% increase in the number of voxels [...]

Visual System Activity When Listening to Speech: Distracting or Helpful?

Aging is often associated with increased distractibility that may arise from a failure to adequately suppress the processing of irrelevant sensory information. In our recent Cerebral Cortex paper, we show that decreasing word intelligibility was associated with increasing visual cortex activity in younger, middle-aged, and older adults. In addition, age was related visual cortex activity: [...]

Our Recent Frontiers Review Manuscript on the Aging Brain and Cognition

Older adults experience slowed processing speed and the severity of slowed processing speed is a strong predictor of age-related cognitive decline and independence.  In our recent manuscript in the journal Frontiers in Neuroscience we review the structural changes observed in brains of older adults that occur with slowed processing speed.  The most consistently observed structural [...]