“TARGET” LOCALIZATION FOR THE FMRI NEUROFEEDBACK

A “TARGET” LOCALIZATION FOR THE FMRI NEUROFEEDBACK OF EMOTIONS IN A PREFRONTAL CORTEX

Melnikov M.Ye.1, Bezmaternykh D.D.1 , Savelov A.A.2, Petrovskiy E.D.2, Pokrovskiy M.A.2, Shtark M.B.1, Kozlova L.I.1

1Federal Research Center of Fundamental and Translational Medicine, Research Institute of Molecular Biology and Biophysics;
2International Tomography Center SB RAS e-mail: mikhail-melnikov@mail.ru

Development of imaging of metabolic activity in the certain cerebral regions led to the establishment of real-time fMRI neurofeedback (rt-fMRI NFB). The rt-fMRI NFB effect is dramatically dependent on the target area (region of interest, ROI) choice.
The aim of the current research was to define potentially effective ROI to influence emotions of ones suffering from depression. Individual ROI localization in each patient using a functional probe is mostly ineffective for prominent variability of the fMRI response (region “migrates” from recording to recording and sometimes is absent).
We consider the anatomical ROI localization based on the previously collected data to be a solving of this problem. The pioneers in the field utilized signals from two main regions, the amygadala and the various frontal regions (prefrontal cortex, anterior cingulate, anterior insula etc.). Our own research with a long-lasting demonstration of emotionally salient (positive and negative) images from a standardized database to healthy volunteers and slightly depressed patients led to non-satisfactory results: the ROIs localized were not associated with emotional information.
The data of brief experiments with demonstration of blocks of emotional or neutral images and also of neurofeedback sessions patients underwent under condition of individual pre-session ROI definition with a similar probe point to presence of comparatively universal ROI. ROI is a nearly symmetric bilateral cluster in an anterior cingulate and medial prefrontal cortex with approximate MNI coordinates of center –8; 46; –7. This area may be easily controlled with emotional strategies; however, it does not discriminate emotional valence. Lateral prefrontal regions were more discriminative concerning positive emotions. Mentioned ROIs are considered by our group as optimal for a neurofeedback training for patients with mild and moderate depression.
The study is supported by Russian Science Foundation grant No 16-15-00183.
 

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