The human brain presents outstanding challenges to science and medicine. Brain function and structure span broad spatial scales (from single neurons to brain-wide networks) as well as temporal scales (from milliseconds to years). Currently, none of the tools at our disposal to study the brain can fully capture its structure and function across these diverse scales - “the neuroimaging puzzle”. This poses crucial limitations to our understanding of how the brain works, and how it is affected by numerous diseases.
Contents and objectives of the research project
The central goal of this project is to expand currently available tools for non-invasive human brain imaging, to bridge critical gaps in the neuroimaging puzzle. We will develop new methodologies focused on ultra-high field magnetic resonance imaging (UHF MRI), and its combination with electroencephalography (EEG). New contrast mechanisms and technological advances enabled by UHF MRI and EEG will be explored to allow unprecedented views into the microstructure of brain regions like the thalamus, and to capture the activity of large-scale neuronal networks in the brain with high sensitivity, temporal and spatial specificity. These advances will be directly applied to address open questions in the diagnosis and treatment of essential tremor, and psychosis.
Scientific and societal context of the research project
Improved brain imaging techniques are critical to help us advance our understanding of how the brain works, and to detect and characterize diseases more effectively, thereby improving their clinical management and leading to a healthier population. The non-invasive characterization and treatment of neurodegenerative diseases like tremor is particularly relevant to our aging modern societies.
The development of improved non-invasive brain imaging techniques is crucial to achieve a more complete picture of the brain’s structure and function, in health and disease. Magnetic resonance imaging (MRI) is a valuable imaging modality, and new systems at ultra-high field have yielded remarkable gains in sensitivity, spatial and temporal specificity. In particular, magnetic susceptibility-based MRI at 7T has recently shown contrast enhancements that outperform conventional modalities in important brain regions, like the thalamic nuclei. While promising, these findings need more extensive validation, and a clearer understanding of the observed contrast. In the functional domain, the combination of functional MRI (fMRI) with scalp electroencephalography (EEG) at fields up to 3T has enabled rich descriptions of brain network activity. Yet, the dynamic, time-varying aspect of this activity remains poorly studied, as does the role of smaller areas like the thalamic nuclei. EEG-fMRI at 7T could help overcoming these limitations, but remains technically challenging due to important compatibility issues.
This project seeks to develop advanced susceptibility-based imaging and EEG-fMRI techniques at 7T, in humans, and translate them to address unmet needs in basic and clinical neuroscience. First, we will acquire and optimize susceptibility imaging modalities, match them against atlas information, and validate them in thalamic nuclei targeting for radiosurgery in essential tremor. In parallel, we will implement and validate new EEG modifications to enable EEG-fMRI at 7T with state-of-the-art fMRI sensitivity and acceleration capabilities. Subsequently, the new MRI and EEG-fMRI techniques will be applied to humans, to pursue a finer understanding of large-scale brain networks. These approaches will also be applied to individuals with psychosis, to study its alterations in network activity.
This project will combine and improve cutting-edge neuroimaging techniques, expanding their sensitivity, temporal and spatial specificity, to levels that have not been achieved to date. These gains will be applied to pursue novel insights into the spatiotemporal dynamics and nature of network activity, improve non-invasive thalamotomy planning, and study functional alterations in psychosis. Beyond the proposed applications, these techniques could bring novel insights into numerous other questions in basic and clinical neuroscience alike, and are planned so as to be easily disseminated across imaging sites.
Last updated:20.03.2022
