D.A. Kovalishina1, V.A. Orlov2, S.I. Kartashov3

1–3 National Research Center "Kurchatov Institute" (Moscow, Russia)

1 kovalishina_da@nrcki.ru, 2 Orlov_VA@nrcki.ru, 3 Kartashov_SI@nrcki.ru

This study presents the results of a comparative analysis of functional brain connectivity between patients with schizophrenia and healthy controls. The investigation was carried out using resting-state functional magnetic resonance imaging, a non-invasive method that enables the assessment of spontaneous neural activity and interregional synchronization of the brain at rest.

The data were acquired on a Magnetom Verio 3.0 Tesla MRI scanner (Siemens, Germany) at the National Research Center “Kurchatov Institute.” Resting-state fMRI sessions were conducted under standardized conditions to ensure the reliability of functional connectivity measurements. Preprocessing and statistical analysis were performed using widely accepted neuroimaging pipelines, including correction for head motion and physiological artifacts, spatial normalization, and filtering of low-frequency fluctuations relevant for resting-state connectivity studies.

Functional connectivity matrices were computed for each participant by estimating pairwise correlations between predefined brain regions of interest. Group-level comparisons between schizophrenia patients and healthy controls were performed to identify statistically significant alterations in connectivity patterns.

The results revealed pronounced differences in functional connectivity between the two groups. Specifically, patients with schizophrenia exhibited significantly reduced connectivity strength between several cortical and subcortical regions compared to healthy individuals. Notably, these deficits were localized exclusively to the left hemisphere of the brain. This hemispheric specificity suggests that lateralized disruptions in neural communication may represent a characteristic feature of schizophrenia-related functional dysconnectivity.

The observed left-hemispheric connectivity reductions align with previous evidence highlighting structural and functional asymmetries in schizophrenia and provide further support for theories of impaired interregional integration underlying cognitive and clinical symptoms of the disorder. Our findings contribute to the growing body of research demonstrating that schizophrenia is associated with selective disruptions in large-scale brain networks, and underscore the potential of resting-state fMRI as a tool for identifying neurobiological markers of psychiatric conditions.

In conclusion, this study highlights significant left-hemispheric deficits in functional brain connectivity in patients with schizophrenia. These results not only deepen our understanding of the neural mechanisms of the disorder but also open new avenues for exploring lateralized biomarkers that could inform diagnostic and therapeutic strategies in clinical practice.

Kovalishina D.A., Orlov V.A., Kartashov S.I. Functional connectivity deficits in patients with schizophrenia compared with controls
as measured by resting-state functional magnetic resonance imaging. Technologies of Living Systems. 2026. V. 23. № 2. Р. 64-72. DOI: https://doi.org/10.18127/j20700997-202602-06 (In Russian).

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