BrainSynch - Large Scale Interactions in Brain Networks and Their Breakdown in Brain Diseases

The long-term goal of this project is to understand how neuronal assemblies exchange information (functional or neuronal communication), and how variability in neuronal communication explains variability in behavioural performance, both in the intact and injured brain. Communication involves temporal interactions between neuronal assemblies either locally within an area or large-scale between areas. We concentrate on large-scale interaction that occur at two different temporal scales: 'slow' (< 0.1 Hz) fluctuations of the blood oxygen level dependent (BOLD) signal easily measured with functional magnetic resonance imaging (fMRI), and 'fast' (1-150 Hz) neuronal oscillations measured at high (multi-unit activity (MUA), local field potential (LFP)) or low (electroencephalographz, EEG; magnetoencephalographz, MEG) spatial resolution. We wish to demonstate that these two phenomena are mechanistically linked and are behaviorally significant. A potentially important clinical application is the development of easy-to-use diagnostic measures of neuronal communication for many brain diseases such as stroke, traumatic head injury, multiple sclerosis, and Alzheimer's disease.