PubMed Health⌕ Search

Biomedical subjects

L G Uvarova

Publications and source records attributed to L G Uvarova.

13 recordsLinked to original sources
PubMed2005

[Peculiarities of EEG dynamics in cognitive activity demanding persistent attention in patients with schizophrenia and schizoaffective psychosis and their relatives].

The search for neurophysiologic correlates of attention and working memory dysfunction in families with schizophrenia, 55 patients with schizophrenia and schizoaffective psychosis, 91 unaffected first degree relatives and 48 mentally normal subjects without family history of mental disorders have been studied. Changes in power of 5 EEG frequency bands in 16 records during serial mental arithmetic tasks were analyzed. Abnormalities in EEG reactivity were found both in patients and their relatives. Both groups were characterized by diffuse elevation of delta-rhythm power, the signs of hypoactivation and inversion of reaction asymmetry for different rhythm bands in the frontal area. In relatives, more pronounced attention dysfunction corresponded to more expressed abnormalities in EEG reactivity. Moreover, patients demonstrated insufficient depression of alpha and fast waves activity in the posterior cortex areas relevant to arithmetic activity. The results obtained allow considering an impaired reaction of alpha and fast rhythms inhibition in the posterior cortex areas as characteristic of the disease, and diffuse elevation of delta-waves power and frontal lobe hypoactivation with the inversion of reaction asymmetry as familial features that might reflect an impact of the factors predisposing to psychosis. This predisposition emerged during the cognitive task involving sustained attention and working memory.

Adult↗
PubMed2002

[Neuromorphologic and psychological correlates of electrical brain activity in patients with schizophrenia and their relatives].

The study aimed at elucidation of potential correlations between EEG features, neuromorphologic and psychological characteristics in patients with schizophrenia and in subjects with familial predisposition to the disease. EEG has been conducted in 71 patients, 162 first-degree relatives of schizophrenia subjects and 67 healthy controls. In the patients and relatives, correlations of power indices for 7 frequency ranges of resting EEG with computed tomography and cognitive parameters were analyzed. The patients revealed negative correlations between slow EEG rhythms and sizes of bodies as well as of posterior horns of lateral ventricules. Positive correlations were shown between expression of alpha- and beta-bands and verbal memory. In the relatives, an increase of slow and fast EEG rhythms power correlated with reduction of sizes of ventricular system regions studied and with deterioration of cognitive indices (mental activity, attention, memory). Overall, the data obtained indicate negative functional consequences of slow and fast EEG rhythms power augmenting in subjects at high genetic risk for schizophrenia, but do not confirm a hypothesis that ventricular enlargement causes EEG slowing in schizophrenia.

Adult↗
PubMed1996

[The genetic aspects of the neuropsychology of verbal memory in schizophrenia].

Genetic study methods were used while examining the families with schizophrenic patients to study the relationships between computerized tomographic and resting ECG parameters with memory for information, which differed in degrees and ways of organization. In patients, memory performance was affected both by genotype-controlled high-frequency alpha-rhythm subranges and by integral delta-rhythm values determined by environmental factors. A significant role of the right hemisphere was found for all forms of remembering. In a group of relatives, predictors of different memory forms differed in frequency and topographic characteristics to a greater degree. These predictors mainly included neuromorphological parameters and power values of alpha-rhythm ranges. Most predictors were under considerable genetic determination.

Adolescent↗
PubMed1995

[A multivariate genetic analysis of the data from a complex study of the predisposition to schizophrenia].

49 families of schizophrenics (49 probands and their 106 first-degree relatives) were studied by means of psychological methods, EEG and computed tomography. Multivariate genetic analysis were performed to assess genetic and environmental components of parameter phenotypic variance and relations between the parameters and liability to schizophrenia, including formation of discriminant functions for classification of individuals into high risk and normal groups and estimation of the functions heritability. Besides, correlations between parameters of neuromorphological, neurophysiological and psychological levels were calculated. The heritability of most EEG and CT parameters were between 41 and 98%. Among psychological variables only mediated and logic memory seem to be under sufficient genetic control (relatively 62 and 42%). Discriminant functions derived from psychological and EEG parameters, allow to differentiate correctly individuals into high risk and normal groups in 76-88% cases. Results of correlational analysis of psychological and biological variables suggest that there are both system and separate genetically determined abnormalities related to different levels of pathogenesis.

Adult↗
PubMed1993

[Genetic analysis of the resting EEG parameters of schizophrenics and their relatives].

The heritability of the resting EEG parameters was studied in 45 schizophrenic families. In offspring--parent pairs (N = 94) and sibs pairs (N = 27) high correlation of average power values of frequency bands between relatives was found (r > 0.5 for alpha and beta power; r 0.2 to 0.45 for delta and theta power in different electrode placement). Linear discriminate functions (LDF) to separate 1) a control group (N = 20) from healthy relatives (N = 46), 2) control group from relatives with borderline pathology (N = 36) and 3) healthy relatives from relatives with borderline pathology were obtained. True classification is possible in 79%, 81% and 76% cases, heritability coefficients of LDF are 47.7, 64.6 and 57.1% respectively.

Adolescent↗
PubMed1985

[Relation between the dynamics of EEG indices after a single dose of the tranquilizer phenazepam and its efficacy during a course of treatment of patients with borderline neuropsychological disorders].

The effect of a single phenazepam dose (1-2 mg) on the power of EEG frequency ranges, their interhemispherical asymmetry and the level of intra- and inter-hemispherical correlations was studied in 78 patients with borderline neuropsychic disturbances divided into four groups depending on the efficiency of phenazepam therapy. Different variants of reactions of EEG parameters related to the characteristics of the clinical action of the drug in different groups of patients were identified. High therapeutical efficacy of phenazepam was associated with a complex of bilateral, relatively generalized changes in power of beta- and alpha-ranges, characteristic of action of benzodiazepins and combined with a predominantly right-side decrease in theta-range and the absence of any significant dynamics of the initially intact correlations of the EEG. Patients with inadequate efficiency of phenazepam showed a topographically-limited and incomplete complex of changes in the power of frequency ranges. They also had alterations in the level of EEG correlation.

Adolescent↗
PubMed1984

[Relation between the effect of tranquilizers and various features of personality structure among patients with borderline states].

The authors revealed differences in the clinico-psychopathological structure, therapeutic time-course and efficiency of the treatment by tranquilizers (e. g. phenazepam, a drug whose effect is typical for the entire group of tranquilizers) in 86 patients with borderline states, the nature of differences depending on the typological characteristics of their personality structure. Hypersthenia was associated with a tranquilo-sedative effect while in hyposthenia a tranquilo-stimulating effect was observed. Electroencephalographic examinations also point to various routes of realization of the modulating influence of tranquilizers.

Anti-Anxiety Agents↗
PubMedDate not supplied

[Correlation of the clinical pharmacological action of a single dose of fenazepam with the EEG dynamics and pharmacokinetics].

Interaction between the clinical, EEG-effects and phenazepam concentration in the blood was studied in 111 patients with neurotic disorders after intake of the test drug dose (2 mg) administered singly and on the 14th day of the treatment. It was established that EEG changes commonly induced by benzodiazepines supervene primarily within the interval of 1 to 3 h after a single intake which correlates with the maximal degree of the tranquilizing, somnolent and myorelaxant drug action. It was demonstrated that the clinical and EEG-effects occur before attainment of the maximal phenazepam concentration and then become less potent, with preservation of the high blood drug level. Intake of the test dose during the treatment course is characterized, as compared with the effect of a single intake, by less marked clinical action of the drug and the lack of significant changes on the EEG and in the blood phenazepam concentration.

Adult↗