Multimodal neuroimaging of motor dysfunction in autism spectrum disorders
University of Colorado, Denver
Most experts do not see children with Autism Spectrum Disorders (ASD) as having motor problems. However, it is well established they exhibit a robust deficit in imitating the actions of other people. It is hypothesized that imitation difficulties in ASD are due to low-level motor impairments. The literature suggests that dysfunctional integrative mechanisms in ASD result from reduced neuronal synchronization, notably through the GABAergic and glutamatergic transmitter systems. Furthermore, the known relationship between motor cortical oscillations to GABA corroborates this idea. This study is designed to see to what extent children with autism have motor problems that underlie their inability to imitate. The aim is to better characterize motor imitation impairments, in order to later design motor-based biomarkers to allow an early detection of individuals with autism. For this purpose, children with ASD and children with no personal or familial history of autism will be asked to execute simple finger movements and finger observation-imitation sequences. The signals produced in their brain during these movements can be recorded in our laboratory through magnetoencephalography. Brain responses to the movement will be studied differences between the two groups will be explored. In collaboration with specialized scientists, changes in brain chemistry will be evaluated with a non-invasive method called in vivo magnetic resonance spectroscopy. The goal is to correlate signals and neurotransmitters in the region of the brain that is responsible for motor movements, in children with autism compared to non-autism kids. In parallel, the study aims to identify relevant motor clinical assessments to highlight these differences. The combination of these different techniques is appropriate to define motor-specific features that are impaired in autism and that will lead to promising diagnosis outcome. This fellowship provides the opportunity to get the skills and expertise necessary to conduct this project. The three mentors will provide extensive knowledge of human brain electrophysiology and training in clinical and developmental motor issues relevant to autism. The training will include screening and assessment for children with autism through parental interview and through neuropsychiatric testing as well as magnetoencephalography.