Differences of EEG Frequency and Spatial Parameters in Depressive Female Adolescents With Suicidal Attempts and Non-suicidal Self-injuries.

Background. Both non-suicidal self-injuries (NSSIs) and suicidal attempts (SAs) in adolescence represent significant risk factors for consequent suicide, but neurophysiological markers and predictors of these two forms of auto-aggressive behavior have been studied insufficiently. Objective. The aim of the study was to identify the differences of electroencephalographic (EEG) frequency and spatial parameters between depressive female adolescents with solely NSSI, and with combined NSSI + SA behavior in their history. Methods. The study included 45 female depressive in-patients aged 16-25 years. Baseline resting EEG spectral power, asymmetry, and coherence were analyzed in 8 narrow frequency sub-bands. Results. In the NSSI + SA subgroup (n = 24), the spectral power of parietal-occipital alpha-2 (9-11 Hz) was higher than in the NSSI subgroup, its focus was localized in the right hemisphere, and alpha-3 (11-13 Hz) spectral power was higher than alpha-1 (8-9 Hz). In the NSSI subgroup (n = 21) alpha-1 spectral power was higher than alpha-3, and foci of alpha-2 and alpha-3 were localized in the left hemisphere. EEG coherence was also higher in the NSSI + SA subgroup than in the NSSI subgroup, especially in frontal-central-parietal regions. Conclusions. The spatial distribution of the EEG frequency components in the NSSI + SA subgroup reflects the greater activation of the left hemisphere that is more typical for the EEG of individuals with an increased risk for suicide. In the NSSI subgroup, the right hemisphere is relatively more activated, and EEG coherence is lower, which is more typical for EEG in depressive disorders. The results obtained suggested the use of EEG to clarify the degree of suicidal risk in depressive female adolescents with NSSI.

Neurobiological parameters in quantitative prediction of treatment outcome in schizophrenic patients.

The aim of the study was to reveal the set of neurobiological parameters informative for individual quantitative prediction of therapeutic response in schizophrenic patients. Correlation and regression analyses of quantitative clinical scores (by Positive And Negative Syndromes Scale - PANSS), together with background EEG spectral power values and four immunological parameters: enzymatic activity of leukocyte elastase and of alpha-1 proteinase inhibitor, as well as serum levels of autoantibodies to common myelin protein and to nerve growth factor, were performed in 50 patients (all females, aged 32.9±10.8 years) with hallucinatory-delusional disorders in the frames of attack-like paranoid schizophrenia. Background neurobiological data obtained before the beginning of syndrome based treatment course (at visit 1) were matched with PANSS clinical scores of the same patients after treatment course at the stage of remission establishment (at visit 2). The multiple linear regression equations were created which contained only 3 to 4 (from initial 80) background EEG parameters and one of four immunological parameters. These mathematical models allowed prediction from 65% to 76% of PANSS scores variance after treatment course (at visit 2). The data obtained may be used for elaboration of methods of individual quantitative prediction of treatment outcome in schizophrenic patients.