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.

Saccadic dysfunction in patients with hypoxic-ischemic encephalopathy.

Electrophysiological monitoring of saccadic eye movements in patients with hypoxic-ischemic encephalopathy (HIE) was carried out. Externally guided saccades (prosaccades) were recorded using a patented hardware-software complex for studying the subject's physical activity. Recordings were performed in two independent experimental procedures - for saccades separately and when they were in coordination with the motion of head and hand. In both cases statistically significant differences in latent periods and durations of saccadic eye movements were noticed in HIE patients in comparison with healthy subjects of the same age group (p<0.05). Jerking and deviation of eyes after fixing the gaze on a target were often present in HIE participants. In some cases saccades of patients were asymmetrical among themselves. We found HIE induced changes in the parameters of autosaccades as well, expressed through the instability of gaze fixation periods, sometimes asymmetric eye movements, slow gaze shift from one target to another and disturbance of gaze stabilization (as jerking of the eyeballs during the saccadic period).

Hardware-program complex for inspection of eyes, head and hand movements coordination of the man.

It is presented hardware- program complex for eyes, head and hand separate movement's check-up, and their coordination check-up in the integrated movement act. Patients with movement disorders are surveyed by using this complex. As an example there are shown differences in movement parameters value (a stage of latency, duration, frequency etc.), of patients with different stages of Parkinson disease (PD) by using several tests. Analysis of head, eyes and hand movement's trajectories can be used for early PD diagnostics.