Sometimes exceptional ability in one area is paired with profound disability in another. A UI collaboration between researchers at the Belin-Blank Center and the Iowa Neuroscience Institute has begun to identify differences in the brains of these twice-exceptional (2e) individuals. The team, led by Jake Michaelson, PhD, the Roy J. Carver Professor of Psychiatry and Neuroscience, focuses on a key aspect of this ability-disability profile: processing speed.
Many autistic 2e individuals exhibit extremely high verbal abilities alongside significantly slower processing speeds. This cognitive pattern offers a unique window into brain function and organization in some forms of autism and might explain challenges in highly dynamic settings like social interaction.
Diffusion tensor imaging (DTI) allows the team to visualize white matter tracts in the brain. These tracts, composed of myelinated axons, connect different brain regions and play a crucial role in information processing speed. In this image, the red, blue, and green colors show the direction of these white matter “cables” through the brain.
With the help of a growing number of participants and the UI’s cutting-edge 7 Tesla MRI scanner, the team has begun to find evidence for the importance of the corpus callosum, a key “information interchange” in processing speed. One hypothesis is that the high verbal ability in 2e individuals might be explained by more efficient connectivity within a hemisphere, while integration of signals across hemispheres is diminished, manifesting as slower processing speed.
Beyond neuroimaging, the team and their research participants are helping to better understand twice-exceptionality through the development of new cognitive assessments that can be administered quickly and repeatedly. These new assessments can help to show how cognitive ability can change depending on a variety of factors like medication, sleep, and stress.
The team is also looking at genetic factors to aid in understanding biological mechanisms that support processing speed. These and other innovative aspects of the study will help deliver new understanding into the factors that affect processing speed, whether processing speed can be improved, and whether those gains translate into improvements in quality of life.
