Identifying Circuits Dysfunctions in Schizophrenia with Optically-Pumped Magnetometers (OPM): A combined OPM-MEG/EEG and Computational Modelling Study

• Applicants: Dr. Tilmann Sander-Thömmes; Professor Dr. Peter Uhlhaas
• Subject Area: Biological Psychiatry ; Human Cognitive and Systems Neuroscience
• Term: since 2021
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 460785001

In this project, we will use novel Optically-Pumped Magnetometers (OPM) to assess changes in brain activity in patients with schizophrenia. OPMs have been recently introduced as a promising approach in non-invasive electrophysiology that have significant advantages over conventional Magnetoencephalograpical (MEG) systems with Superconducting Quantum Interference Device (SQUIDs) in terms of signal to noise and maintenance costs. However, their potential to identify electrophysiological alterations in psychiatric conditions, such as schizophrenia, has not been explored so far. In the current project, we will first recruit a sample of healthy control participants and obtain parallel OPM-MEG/Electroencephalographical (EEG) recordings during three sensory tasks involving visual and auditory stimuli. In addition, SQUID-MEG measurements will be obtained to allow comparisons between the three different measurement approaches. We will analyse OPM/SQUID-MEG as well as EEG-recordings for rhythmic activity (neural oscillations) at low- and high-frequency ranges as well as for event-related potentials/event-related fields (ERPs/ERFs) at sensor and source-level. In the second part of the project, we will recruit 30 patients with schizophrenia who are currently receiving antipsychotic medication and carry out OPM-MEG/EEG-recordings with the same tasks performed in controls. Alterations in neural oscillations and ERFs/ERPs will be systematically assessed between controls and schizophrenia patients to establish effect sizes for the different recording techniques. We will focus in particular on neural activity in auditory and visual cortices as there is evidence to suggest that the registration of incoming sensory information is compromised in patients with schizophrenia. Moreover, we will systematically assess relationships between changes in OPM-MEG/EEG-recordings, clinical symptoms and cognitive impairments in patients with schizophrenia. In the final part of the project, we will use a computer model that allows to simulate patterns of brain activity to relate alterations in OPM-MEG and EEG-recordings to underlying changes in neurotransmitter-systems in schizophrenia. Specifically, we focus on the role of inhibitory neurotransmissions as well as on the contribution of the excitatory neurotransmitter Glutamate as there is evidence to suggest that certain symptoms and cognitive impairments in schizophrenia are due to the impaired interaction between these two transmitter-systems. Through this approach, we hope to gain new insights into the underlying causes of the disorder that could be potentially relevant for the development of novel treatment approaches.

• DFG Programme: Research Grants
• International Connection: United Kingdom
• Cooperation Partner: Dr. Rick Adams