D.A. Kovalishina1, V.A. Orlov2, Yu.A. Pirogov3

1,2 National Research Center “Kurchatov Institute” (Moscow, Russia)
3 Lomonosov Moscow State University (Moscow, Russia)
1 kovalishina_da@nrcki.ru

The paper investigates the functional connectivity of the brain in patients with schizophrenia and uses functional magnetic resonance imaging to analyze changes in this connectivity in response to transcranial magnetic stimulation. The work focuses on pipeline validation and the selection and evaluation of metrics for assessing functional connectivity in patients with schizophrenia both before and after transcranial magnetic stimulation therapy in order to identify differences between patient groups. This selection is necessary to create a model of pathophysiological changes in the brain of patients with schizophrenia. The creation of such a model will allow schizophrenia to be diagnosed based on objective and measurable biomarkers supported by a well-founded evidence base, instead of relying on indirect signs. A total of 7 patients with schizophrenia (mean age 40.8±2.1) were recorded before and after Transcranial magnetic stimulation (TMS) therapy. Data were collected using a GE Signa Premier 3T tomograph. Specific metrics such as correlation coefficients and transfer entropy are used to analyze connectivity in different brain regions, with an emphasis on assessing their significance in the context of therapy. The researches show that transcranial magnetic stimulation leads to statistically significant changes in functional connectivity of the brain in patients with schizophrenia. Conclusion: The correlation family metrics in this work showed the greatest difference between the groups of patients before and after TMS therapy. The nature of the calculation of these metrics lies in the calculation of the Pearson correlation, which, in turn, is one of the most common statistical parameters. The choice of these metrics as one of the main ones in the calculation of the model of pathophysiological changes in the brain of patients with schizophrenia will allow the use of a variety of tools from different scientific disciplines.

Kovalishina D.A., Orlov V.A., Pirogov Yu.A. Functional connectivity of neural networks of the brain in patients with schizophrenia before and after TMS therapy. Biomedicine Radioengineering. 2025. V. 28. № 7. P. 5–16. DOI: https:// doi.org/10.18127/j15604136-202507-01 (In Russian)

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