Prospects for Future Methodological Development and Application of Magnetoencephalography Devices in Psychiatry

Abstract

Magnetoencephalography (MEG) is a functional neuroimaging tool that can record activity from the entire cortex on the order of milliseconds. MEG has been used to investigate numerous psychiatric disorders, such as schizophrenia, bipolar disorder, major depression, dementia, and autism spectrum disorder. Although several review papers on the subject have been published, perspectives and opinions regarding the use of MEG in psychiatric research have primarily been discussed from a psychiatric research point of view. Owing to a newly developed MEG sensor, the use of MEG devices will soon enter a critical period, and now is a good time to discuss the future of MEG use in psychiatric research. In this paper, we will discuss MEG devices from a methodological point of view. We will first introduce the utilization of MEG in psychiatric research and the development of its technology. Then, we will describe the principle theory of MEG and common algorithms, which are useful for applying MEG tools to psychiatric research. Next, we will consider three topics-child psychiatry, resting-state networks, and corticosubcortical networks-and address the future use of MEG in psychiatry from a broader perspective. Finally, we will introduce the newly developed device, the optically-pumped magnetometer, and discuss its future use in MEG systems in psychiatric research from a methodological point of view. We believe that state-of-the-art electrophysiological tools, such as this new MEG system, will further contribute to our understanding of the core pathology in various psychiatric disorders and translational research.

Recent Advances and Future Directions in Brain MR Imaging Studies in Schizophrenia: Toward Elucidating Brain Pathology and Developing Clinical Tools

“…Due to their non-invasiveness and excellent temporal resolution in the millisecond range, neurophysiological approaches, such as electroencephalography (EEG) and magnetoencephalography (MEG), have revealed novel insights into sensory and cognitive abnormalities in patients with schizophrenia. 67,121,122 In addition to cross-sectional studies, longitudinal studies of EEG/MEG indices have also attracted attention as biomarkers for detecting the onset of schizophrenia and subjects who are at a clinical high risk. [123][124][125] An MRI research is generally conducted for a specific condition (e.g., schizophrenia) using a machine in a site, given that the multi-site data as the aggregation of the case-control studies (i.e., X a,x , X b,y , and X c,z ) are unable to differentiate between sampling and measurement biases.…”

Disrupted local beta band networks in schizophrenia revealed through graph analysis: A magnetoencephalography study

“…They stated that source‐level connectivity measures in MEG may yield artifacts strong enough to render the graphs meaningless, 80 or they may be consistent with whole‐brain connectivity studies that have shown consistency between fMRI and MEG results 23,81 . Noise rejection methods used in MEG have grown remarkably in recent years 82 . We performed noise reduction using oversampled temporal projection, Elekta Neuromag Maxfilter, notch filter, and ICA as preprocessing for the connectivity analysis.…”

“…23,81 Noise rejection methods used in MEG have grown remarkably in recent years. 82 We performed noise reduction using oversampled temporal projection, Elekta Neuromag Maxfilter, notch filter, and ICA as preprocessing for the connectivity analysis. These methods, developed in recent years, are stronger than the methods of Rutter et al, who rejected epochs with high eye artifacts and head movement of over 0.5 cm, and used only a notch filter and a bandpass filter.…”

Trends in big data analyses by multicenter collaborative translational research in psychiatry

“…Electroencephalography and magnetoencephalography studies Electroencephalography (EEG) and magnetoencephalography (MEG) are noninvasive neurophysiological methods with excellent temporal resolution in the millisecond range that have revealed novel insights into cognitive and sensory abnormalities in individuals with psychiatric disorders, especially in patients with SZ. [70][71][72] Auditory-related symptoms (especially auditory hallucinations) are known to be prominent compared to other sensory modality symptoms in SZ, and auditory-related deficits can be found even at the early sensory processing level (e.g. tone matching), which could contribute directly to impairments in cognitive and social functioning.…”