[Impairments of Neurocognitive Mechanisms of Decision-Making in Depression.]

A multidisciplinary clinical-psychological-neurophysiological study has been performed in 28 depressive patients (females, aged 18-56) and 50 healthy volunteers (females, aged 18-55) in order to analyze the relationships between the impairments of neurocognitive mechanisms of decision-making based on logics and considerations or on emotional experience (emotional learning) in uncertain situation and clinical and neurophysiological signs of depression. The severity of depression was assessed quantitatively using Hamilton's Depression Rating Scale (HDRS-17). Tests "10 words", Wisconsin Card Sorting Test (WCST), and Iowa Gambling Task (IGT) were used for quantitative assessment of cognitive functions. Multichannel resting EEG was recorded in all depressive patients in order to assess the brain functional state. Neurocognitive deficit was observed in all the patients; its pronounce correlated positively with the severity of depression. The ability to make decisions based on both logic and considerations (in WCST), which is associated with EEG signs of hypofrontality, and on emotional learning (in IGT) was impaired. Only in depressive patients reduced ability to make rational decisions based on logics and considerations resulttd in a compensatory shift towards decision-making based on emotions, which led to relatively higher results of emotional learning. The data suggests that hypofrontality causes difficulties in making decisions that requires logical reasoning and the disinhibition of subcortical (including hippocampal) brain structures, the activation of which provides better results of emotional learning.

[Transcranial Magnetic Stimulation in the Combined Treatment of Pharmacoresistant Depression: Dynamics of Clinical, Psychological and EEG Parameters].

In order to investigate the mechanisms of the therapeutic effect of transcranial magnetic stimulation (TMS) of the left dorsolateral prefrontal cortex in patients with depression, we studied the dynamics of clinical parameters, a number of cognitive functions, and the spectral structure of resting EEG in 20 patients with pharmacoresistant depression in the course of combined treatment including TMS. It was shown that short course (10 sessions) of TMS significantly enhanced and accelerated the effect of antidepressants. The course of TMS contributed not only to the reduction of depressive symptoms but also to the improvement of general condition and the recovery of some impaired cognitive functions. The therapeutic effect of TMS seems to be provided by the activation of not only the prefrontal cortex itself but also of some subcortical structures closely linked with it. Thus, TMS appears to be a promising non-drug method for the treatment of clinical conditions and for the correction of brain functional state in patients with depression, including the use in combined treatment of depressive disorders in cases of pharmacoresistance.

[The changes of EEG correlation synchrony at depressive disorder of psychogenic type].

In this work we use the alternative method of assessing the EEG-synchrony which previously has proved its high sensitivity to the differentiation of psychopathological and functional states. The original recording of EEG had been performed in the state of quiet wakefulness with eyes closed for two groups of examinees/patients at the age of 49-82 years: a group of normal subjects (n = 29) and the group of subjects with depressive deviations of F43.21 category according to ICD-10 (n = 51). As a result of research it is received the comprehensive picture of significant topographical, interhemispheric and regional differences between groups of norm and depression. One of basic features of the obtained integrated picture is existence at a depression of the extended zones of reduced EEG-synchrony covering the entire premedial region in the frontal-occiptal direction, including intrahemispheric connections as well as lateral frontal-temporal connections in both hemispheres. It testifies to the deep deprivation with depression frontal-occipital and interhemispheric interaction. As a compensatory reaction during depression the increase of synchrony in axial aimed intrahemispheric pairs of derivations. It is noted the similarity of changes in EEG-synchrony topography of depression to those observed in schizophrenia. The used method has provided close to 100% reliability of the classification of the EEG norms and depressive deviations, which makes possible and promising its use as an auxiliary quantitative differential indicator.

[Auditory event-related evoked potentials in dynamics of treatment of affective-delusional conditions].

With the aim to study neurophysiologic correlates and to search for some possible predictors of therapeutic response correlation analysis has been carried out of links between temporal parameters of components of auditory event-related potentials (AERPs) and dynamics of quantitative clinical assessments of mental state conditions in two groups of patients--with depressive-delusional conditions (group 1) and with manic-delusional conditions (group 2) in the frames of attack-like schizophrenia. Statistically significant correlations have been revealed between values of peak latencies of main AERPs components and severity of psychopathologic symptoms before beginning of treatment course, as well as between initial (before treatment course) AERPs temporal parameters and quantitative clinical assessments at the stage of remission establishment. Larger severity of residual positive, negative and common psychopathologic symptoms of schizophrenia (and also of depression and anxiety in group 1) after course of treatment was associated with smaller initial (before treatment course) values of peak latencies of "early" (P1 and N1) and with larger initial values of "late" (P2, N2 and P3) AERPs components in both groups of patients. The data obtained allow to justify basic views on brain mechanisms of affective-delusional disorders, and to reveal possible neurophysiologic predictors of treatment efficacy in such disorders.

[EEG-correlates and possible predictors of efficacy of treatment of endogenous depression].

An analysis of EEG spectral power values and of quantitative clinical scores of depressive conditions has been carried out in dynamics of treatment in 40 patients with endogenous depression with the main goal to study neurophysiologic correlates and to search possible predictors of therapeutic outcome. The reduction of depressive symptoms by the end of the treatment course was associated with EEG signs of improvement of brain functional state. Significant correlations have been revealed between the EEG narrow-band spectral power values and clinical scores. As well, significant correlations have been revealed between some initial (before beginning of treatment) EEG parameters and quantitative clinical scores at the stage of remission establishing. The values of EEG beta-1 and beta-2 spectral power appeared to be such predictors, while initially larger values of EEG beta activity spectral power were associated with higher pronounce of residual depressive symptoms after the treatment course. The data obtained allow to justify basic views on brain mechanisms of various aspects of depressive disorders, and to reveal possible neurophysiological predictors of efficacy of treatment of endogenous depression.

[EEG correlates of suicidal intentions in depressive patients who survived and have not been ill with COVID-19]. / EEG-korrelyaty suitsidal'nykh namerenii u bol'nykh depressiei, bolevshikh i ne bolevshikh COVID-19.

OBJECTIVE: To search for EEG correlates of suicidal intentions in young depressive patients who survived and have not been ill with COVID-19. MATERIAL AND METHODS: We studied 46 female patients, aged 16-25 years, with depressive disorders who had previously had a mild or asymptomatic coronavirus infection («COVID¼ group) and 40 female patients with depressive disorders matched in age, syndromic structure of disorders and the initial severity of depression to patients of the «COVID¼ group but who are known not to have COVID-19 («non-COVID¼ group). The severity of suicidal intentions was assessed by the number of points of item 3 of HDRS-17. In all patients, pre-treatment multichannel background EEG was recorded with spectral power analysis in narrow frequency sub-bands. RESULTS: In patients of the «COVID¼ group, the mean number of points of item 3 of HDRS-17 was slightly higher (at the trend level) than in the «non-COVID¼ group (2.1±1.5 and 1.8±1.6 points, respectively), and positively correlated (p<0.05) with the spectral power values of theta2 (6-8 Hz) and delta (2-4 Hz) EEG sub-bands. In the «non-COVID¼ group, the severity of suicidal intentions positively correlated (p<0.05) with the values of the spectral power of alpha2 (9-11 Hz) EEG sub-band. CONCLUSION: Suicidal intentions increased in depressive patients survived from COVID-19, and their severity is associated with EEG signs of a reduced functional state of the cerebral cortex.

[Clinical-neurophysiological correlations in female adolescents with heboid depression]. / Kliniko-neirofiziologicheskie korrelyatsii u patsientok molodogo vozrasta s geboidnoi depressiei.

OBJECTIVE: To determine EEG markers of depression severity and clarify the brain mechanisms of heboid depression by identifying relationships between clinical and neurophysiological parameters in female adolescents with heboid depression. MATERIAL AND METHODS: A clinical-neurophysiological study of 25 female adolescents, aged 16-25 years, mean age 18.7±2.6 years, with heboid depression (ICD-10 items F31.3-F31.4, F34.0) was carried out. The severity of depressive disorders during hospitalization varied from mild to severe - the HDRS-17 total score ranged from 12 to 37 points (average 26.4±6.5 points). To assess the functional state of the brain, a multichannel EEG recording was performed in a state of calm wakefulness with closed eyes (for 2-3 minutes). EEG was recorded in 16 leads: F7, F3, F4, F8, T3, C3, Cz, C4, T4, T5, P3, Pz, P4, T6, O1 and O2. Data analysis was carried out using descriptive and nonparametric statistics programs from the IBM SPSS Statistics, v.22 package. RESULTS: Differences in the EEG of patients from the norm were detected in the alpha frequency range, SpM values of the alpha2 subrange (9-11 Hz) were statistically significantly lower in the frontal areas (in the left frontal lead F3 p=0.021, in the right frontal lead F4 p=0.006). The patients did not have «highly coherent¼ (Coh >0.80) interhemispheric connections between the frontal-central-anterotemporal regions of the left and right hemispheres in the frequency range of the alpha-rhythm (8-13 Hz). The following correlations (p≤0.05) were revealed: the values of the HDRS-17 total score were positively correlated with the spectral power values of theta1 (4-6 Hz) and theta2 (6-8 Hz) EEG frequency subranges only in the frontal, central and midtemporal leads from the right hemisphere (F4, C4, T4). CONCLUSION: In patients with heboid depression, there is a functional «uncoupling¼ of the frontal-central-anterior-temporal areas of the right and left hemispheres of the brain. It is possible that such a «dissociation¼ and a relatively large activation of the anterior parts of the left rather than the right hemisphere play a role in the weak control of impulsive delinquent behavior in patients with heboid depression. The identified atypical features of the EEG spatial organization and correlations of the EEG frequency structure with clinical parameters are consistent with the atypical clinical picture of heboid depression.

[Clinical-neurobiological correlations in young depressive patients with a history of suicidal attempts]. / Kliniko-neirobiologicheskie korrelyatsii u bol'nykh depressiei molodogo vozrasta s suitsidal'nymi popytkami v anamneze.

The processes of neuroinflammation play an important role in the pathogenesis of endogenous mental disorders, including in patients with autoaggressive behavior. OBJECTIVE: Is to identify the relationships of quantitative clinical, EEG and neuroimmunological parameters in young female patients with depression and a history of suicidal attempts in order to clarify the role of neuroimmune interaction in the pathogenesis of suicidal behavior. MATERIAL AND METHODS: In 35 female patients aged 16-25 years the pre-treatment severity of the depressive state was quantitatively assessed (according to the HDRS-17 scale), and immunological parameters - markers of neuroinflammation (activity of leukocyte elastase and of α1-proteinase inhibitor) in blood plasma using the laboratory technology «Neuro-immuno-test¼ and the EEG absolute spectral power in narrow frequency sub-bands were measured. The relationships between clinical, neuroimmunological and EEG parameters was determined by correlation analysis (according to Spearman). RESULTS: The values of immunological markers of neuroinflammation correlated with EEG signs of increased activation of the cerebral cortex and with the severity of the anxiety component of the depressive state. CONCLUSION: The structure of clinical-neurobiological correlations in the examined patients indicates the involvement of neuroinflammation processes in the pathogenesis of their condition. The results make it possible to clarify the neurobiological factors of the pathogenesis of suicidal behavior in young depressive patients.

[Neuropsychophysiological correlates of reactive depression].

With the aim of justifying of neurophysiological correlates of depressive disorders spectral parameters of EEG, and peak latencies of the "late" components of auditory cognitive evoked potentials, and latencies of sensorimotor reactions have been analysed in middle age and elderly patients (age 53-72) during the therapy of prolonged psychogenuously provoked depressive reaction (F43.21 by ICD-10). Background depression severity has been associated with the EEG signs of decreased functional state of anterior areas of the left hemisphere, and of increased activation of the right hemisphere (especially, of its temporal regions). Pronounced improvement of clinical condition resulted from psychopharmacotherapy led to acceleration ofsensorimotor reactions, and to decrease of peak latencies of the "late" components (P2, N2 P3) of auditory cognitive evoked potentials, that have been associated with the EEG signs of improvement of functional state of posterior brain areas, of facilitation of inhibitory processes in the right hemisphere (especially, in its frontal, central and temporal regions), and of more pronounced activation of frontal areas of the left hemisphere. The data obtained are in good concordance with the views on systemic character of impairments of brain functioning in depression, as well as on preferential role of the left hemisphere in control of positive emotions, and of the right hemisphere role in control of negative emotions.

[EEG predictors of therapeutic response in psychiatry]. / EEG-prediktory terapevticheskogo otveta v psikhiatrii.

The literature review provides data on one of the types of biomarkers - EEG predictors of the therapeutic response of patients with different types of mental pathology. It has been shown that the quantitative parameters of the electroencephalogram (EEG) recorded before the start of the treatment course reflect not only the current functional state of the patient's brain, but also its adaptive resources in terms of the possibility and magnitude of response to therapy. The identified EEG predictors of the therapeutic response in patients with depression, schizophrenia and some other mental disorders have a sufficiently high prognostic ability, sensitivity and specificity in determining responders and non-responders, make it possible to carry out a quantitative prediction of the patient's condition after a course of treatment, and also to assist the clinician in choosing medications for optimal therapy.

[Clinical-neurophysiological correlations in patients with depressive-delusional conditions]. / Kliniko-neirofiziologicheskie korrelyatsii u bol'nykh s depressivno-bredovymi sostoyaniyami.

OBJECTIVE: To analyze a complex of EEG parameters and quantitative clinical evaluations of depressive-delusional conditions in patients with schizoaffective disorder and to clarify their neurophysiological mechanisms. MATERIAL AND METHODS: A study included 25 female patients, aged 22-40 years, with depressive-delusional conditions. Patients were assessed at baseline and after 4-6 weeks of treatment using HDRS and PANSS. EEG was recorded at each visit. RESULTS: Significant correlations were revealed between the values of pre-treatment background EEG spectral power in narrow frequency bands and quantitative pre-treatment and post-treatment scores of patient's clinical conditions. CONCLUSION: The results allow clarifying the brain mechanisms of depressive-delusional disorders and reveal possible EEG-predictors of therapeutic response in its treatment.

[The relationship between quantitative clinical and EEG parameters in the treatment of delusional conditions in patients with attack-like schizophrenia].

OBJECTIVE: To study neurophysiologic correlates of the severity of clinical conditions and to search for possible predictors of therapeutic response in attack-like schizophrenic patients with delusional disorders. MATERIAL AND METHODS: During the treatment of 40 attack-like schizophrenic patients (all females, right-handed, aged 20--50 years old) with delusional disorders, clinical symptoms were quantitatively assessed using PANSS. Resting EEG was recorded with the consequent spectral-coherent analysis. Correlation analysis was performed at the beginning of treatment and at the stage of the development of remission. RESULTS: Significant (p<0.05) correlations between some initial (before treatment) resting EEG parameters and PANSS scores before treatment and at the stage of remission were revealed. The reduction in psychopathologic symptoms after treatment course was associated with the decrease in alpha-3 spectral power in occipital zones and increase of theta-1 and theta-2 spectral power in frontal-central regions. Besides, the number of statistically significant intra-hemispheric and inter-hemispheric links was increased in theta-1 and theta-2 frequency bands in frontal and central regions compared to initial levels. CONCLUSION: These EEG changes reflected the facilitation of cortical inhibitory processes as well as recovery of impaired intra-cortical links i.e. the normalization of the brain integrative activity.

[Comparative dynamics of EEG parameters in elderly depressive patients during monotherapy and combined therapy].

OBJECTIVE: To compare the changes in brain functional state in combined antidepressive treatment (venlafaxine plus cerebrolysin) vs. monotherapy with the same antidepressant in elderly depressive patients using quantitative EEG methods. MATERIAL AND METHODS: Forty patients, aged 60-79 years, mean 67.1±5.7) were randomized to two groups. Patients of group 1 were treated with venlafaxine (4 weeks, in dose of 75-150 mg/day). Patients of group 2 were additionally treated with cerebrolysin (totally 20 i/v infusions during 4 weeks, 20.0 ml in 100 ml isotonic NaCl solution). RESULTS AND CONCLUSION: The significant improvement of clinical conditions was shown by the end of the treatment course using both clinical assessments and HAMD-17, CGI-S, CGI-I and MMSE scores in both groups. The combined treatment with venlafaxine and cerebrolysin in patients of group 2 led to more pronounced improvement of their brain functional state (seen as an increase of spectral power and normalization of frequency alpha band of parietal-occipital EEG) in comparison with patients of group 2 treated by the same antidepressant alone.

[Regression models of interrelationships between clinical and neurobiological parameters in treatment of manic-delusional conditions in attack-like schizophrenia]. / Regressionnye modeli svyazi klinicheskikh i neirobiologicheskikh pokazatelei pri terapii maniakal'no-bredovykh sostoyanii v ramkakh pristupoobraznoi shizofrenii.

OBJECTIVE: to identify a complex of neurobiological parameters informative for the assessment of severity of patient's initial clinical state and for individual prognosis of therapeutic response. MATERIAL AND METHODS: Correlation and regression analyses of clinical scores measured by the PANSS scale, resting EEG spectral parameters and immunological parameters have been performed in 45 patients (mean age 31.3±11.4 years with manic-delusional conditions in attack-like schizophrenia. RESULTS: Neurobiological data obtained before the treatment course were matched with clinical scores of the same patients at the stage of remission establishment after treatment course. The multiple linear regression equations, which contained only 3 to 4 (from 80) initial EEG parameters and one of four immunological parameters, allowed to explain with high significance from 89 to 92% of clinical scores variance before treatment course, and to predict from 72 to 87% of clinical scores variance after treatment course at the stage of remission establishment, as well. CONCLUSION: The data obtained emphasize the role of neurophysiological inhibition deficit and processes of neuroinflammation and neuroplasticity in the pathogenesis of manic-delusional conditions and may be used in practice for elaboration of methods of prediction of treatment efficacy in patients with manic-delusional disorders.

Abnormal recognition of facial expression of emotions in depressed patients with major depression disorder and schizotypal personality disorder.

The aim of this paper is to study the recognition of facial expression of emotions in depressed patients with major depressive disorder (MD) and schizotypal personality disorder (STP). The pictures of sad, emotionally neutral, and happy faces followed by a masking stimulus were displayed for 80 msec on a computer screen randomly in the left or right hemifield of vision (LHF and RHF). The subjects had to respond by pressing a three position key. Multiple analysis of variance revealed that all depressed patients, relative to control subjects, made more errors in a task of recognition of facial affect. The characteristics of impairment of performance were found to be related to the nosology of depression. MD patients revealed significantly impaired recognition of negative (in LHF and in RHF) and positive (in LHF) facial emotions, as well as poorer recognition in the right hemisphere, and reduced hemispheric asymmetry. In remission, they showed statistically significant recovery of recognition function. STP patients were less impaired and showed slightly poorer recognition of sad (in RHF) and happy (in LHF) expressions. This group demonstrated significantly poor recognition of happy expressions, and more marked dysfunction of the left hemisphere. In remission, STP patients failed to improve in recognition of emotion. This suggests, that the features of emotion recognition in MD and STP groups reflect some differences in the neurophysiological mechanisms underlying the affect-related dysfunction in these groups of depressed patients.

[EEG-mapping in Alzheimer-type dementias]. / EEG-kartirovanie pri dementsiiakh al'tsgeimerovskogo tipa.

EEG topographic correlates of the severity and type of Alzheimer-type dementias have been studied in 21 patients with senile dementia (SD) and 18 with Alzheimer's disease (AD) who were subdivided into smaller groups by MMSE grades for the severity of dementia, as well as in 15 mentally normal elderly persons. EEC maps in SD and AD patients differed from those in normal subjects in increased theta-delta EEG spectral power and suppressed alpha-band power that was more pronounced in the left hemisphere in AD than in SD patients. AD and SD patients had also different EEG topographical changes with intensified cognitive dysfunctions. The results suggest that there is a great cholinergic deficiency and cortical rather than subcortical impairments in patients with AD than in those with SD.

[Longitudinal approaches to the problem of clinical heterogeneity of Alzheimer-type dementia]. / Longitudinal'nye podkhody k probleme klinicheskoi geterogennosti dementsii al'tsgeimerovskogo tipa.

A total of 160 patients with Alzheimer-type dementias (ATD), including 84 with Alzheimer's diseases (AD) and 76 with senile dementia (SD), were examined. The initial signs of the disease were analyzed by making a retrospective assessment of informative history data. The prospective follow-up involved clinical, neuropsychological and electrophysiological (EEC mapping, evoked potentials) studies by applying the standardized assessment of results. There was shown to be a set of clinical and paraclinical parameters for the status of ATD patients, indicating a distinct-quantitative and qualitative difference between patients with AD and those with SD and supporting the heterogeneity of ATD.

[Quantitative EEG in early and differential diagnosis of mild dementia of different genesis]. / Kolichestvennaia élektroéntsefalografiia v rannei i differentsial'noi diagnostike "miagkikh" dementsii raznogo geneza.

Quantitative EEG was used to reveal the specific features of its amplitude-frequency parameters and topography in patients with mild dementia of different genesis versus healthy elderly individuals. All four study groups of patients differ in EEC relative spectral density, they also differ from the healthy persons while alpharhythm was suppressed in Alzheimer's disease (AD) and vascular dementia (VD) and there was slower alpha-rhythm and higher theta-activity in senile AD (SAD). Patients with VD were characterized by desynchronized EEG. Factorial and stepwise discriminant analyses of EEG parameters showed that the control group greatly differed from patients with mild dementias. Patient groups mainly with atrophic atrophic AD and SAD or vascular (VD and mixed) dementia were also different whereas the mixed vascular-atrophic group is intermediate in EEC parameters between the VD group and the partially overlapped AD and SDA patient groups. Quantitative EEC data may be thus used for differential diagnosis to optimize therapy and prognosis even in mild dementia.

[Quantitative EEG correlates of the human frontal lobe dysfunction]. / Kolichestvennye EEG-korreliaty disfunktsii lobnykh dolei kory golovnogo mozga cheloveka.

Increased central-parietal EEG theta-2 activity (about 6.5 per sec) was found in children with cognitive disorders (in Rett's syndrome, fragile X-syndrome, infantile autism) and in elderly patients with Alzheimer-type dementia (with prevalence of neuropsychological "frontal" disorders) in the presence of suppressed alpha rhythm. This theta-activity was closely associated with cognitive deficits and possessed a specific functional topography, namely it focused in the parietal region and suppressed by both visual stimulation and motor tests. The similar EEG pattern was observed in some patients treated with neuroleptics and/or during hyperventilation. By taking into account the data available in the literature on motor, oculomotor, regional cerebral blood flow and the probability prediction in frontal lobar dysfunction, it is suggested that the theta-activity described appears in the visuomanual coordination system and is a physiological correlate of decreased functional status of frontal lobes.

[Rhythmic activity of central portions of the cat visual analyzer during different forms of behavior]. / Ritmicheskaia aktivnost' tsentral'nykh otdelov zritel'nogo analizatora koshki pri nekotorykh formakh povedeniia.

Synchronized EEG activity of visual cortex and some other parts of the brain was recorded in cats during milk licking. The frequency range, cortico-subcortical topography and some conditions of its appearance and blockade were analyzed. It was found, that this activity consisted of two rhythms with frequencies of 6--9 and 9--15 c/s and was strongly influenced by visual conditions. By come parameters it also differed from EEG of drowsiness and light sleep. Possible mechanisms and localization of pacemakers of this activity was discussed as well as its similarity to human alpha rhythm.