Репозиторий Университета

© 2020, Springer Science+Business Media, LLC, part of Springer Nature. Objectives. The amplitude and latency of the P300 wave are regarded as basic neurophysiological correlates in studies of cognitive functions. The characteristics of the event-related θ rhythm recorded in the same time period as the P300 wave are less well studied. The aim of the present work was to carry out a complex assessment of the neurophysiological parameters of cognitive processes in health and various degrees of cognitive dysfunction in patients with personality disorders, schizotypal disorders, and schizophrenia. Materials and methods. A total of 124 subjects were studied: 44 healthy subjects (normal), 40 patients with schizophrenia, 22 patients with personality disorder, and 18 with schizotypal disorder. Studies used a probabilistic presentation of significant and non-significant auditory signals. P300 amplitude and latency were determined for each subject, along with power and paired coherence in the event-related θ rhythm, on presentation of significant stimuli. Results and conclusions. All patients, as compared with healthy subjects, were found to have a tendency to decreases in P300 amplitude and increases in latency, with reductions in the power and coherence of the event-related θ rhythm. In schizophrenia, this trend was spatially generalized, while changes in personality disorder and schizotypal disorders were mostly localized and did not reach statistical significance on between-group comparisons. These data may be evidence of gradual weakening of cognitive functions going from normal through schizotypal disorder and personality disorder to schizophrenia, which may correspond to decreases in insight and the ability to foresee the consequences of actions.

© 2020, Springer Science+Business Media, LLC, part of Springer Nature. Objectives. The amplitude and latency of the P300 wave are regarded as basic neurophysiological correlates in studies of cognitive functions. The characteristics of the event-related θ rhythm recorded in the same time period as the P300 wave are less well studied. The aim of the present work was to carry out a complex assessment of the neurophysiological parameters of cognitive processes in health and various degrees of cognitive dysfunction in patients with personality disorders, schizotypal disorders, and schizophrenia. Materials and methods. A total of 124 subjects were studied: 44 healthy subjects (normal), 40 patients with schizophrenia, 22 patients with personality disorder, and 18 with schizotypal disorder. Studies used a probabilistic presentation of significant and non-significant auditory signals. P300 amplitude and latency were determined for each subject, along with power and paired coherence in the event-related θ rhythm, on presentation of significant stimuli. Results and conclusions. All patients, as compared with healthy subjects, were found to have a tendency to decreases in P300 amplitude and increases in latency, with reductions in the power and coherence of the event-related θ rhythm. In schizophrenia, this trend was spatially generalized, while changes in personality disorder and schizotypal disorders were mostly localized and did not reach statistical significance on between-group comparisons. These data may be evidence of gradual weakening of cognitive functions going from normal through schizotypal disorder and personality disorder to schizophrenia, which may correspond to decreases in insight and the ability to foresee the consequences of actions.

© 2018, Media Sphera Publishing Group. All rights reserved. Objective. To test the main hypothesis that the deficit phenomena in schizophrenia act not in the «pure» form, but in the form of aggravating personality characteristics, forming so-called «common» syndromes with personality disorders (PD). Material and methods. The results of the psychopathological study (with the use of psychometric methods) of deficit disorders in a sample of 170 patients with schizophrenia and schizophrenia spectrum disorders (63 men, 107 women) are presented in relation to the abnormal structure of premorbid personality (PD of clusters A, B, C). An analysis of negative symptoms according to the comparability of defect to the profile of premorbid personality made it possible to distinguish three groups of deficit states associated with PD - «common syndromes»: defensive schizoidy by the type of deficit schizoid and expansive schizoidy by the type of «verschroben» (cluster A); pathological hysterical infantilism, malignant hysteria and defective erotomania (cluster B); pseudo-psychasthenia and pathological rationalism (cluster C). Results. It has been found that the symptomatology of «common syndromes» is subject to patterns reflecting the dichotomy of the basic defect. This pattern is valid not only for one single cluster of PD, but extends to all psychopathy- like disorders, regardless of their affiliation with a particular cluster. The pathocharacterological component of the «common syndromes» coexisting with the deficit symptom complexes is subject to the basic deficit component of the defect and is separated into polar dimensions (defensive-expansive) within specific clusters of PD, and then unified in accordance with the dichotomy of schizophrenic defect in categories with the predominance of emotional or apathoabulic disorders. Conclusion. ?sychopathy-like symptom complexes in the space of «common syndromes» can be qualified as a psychopathological construct secondary to basic deficit disorders, and their isolation as an independent entity of negative disorders appears to be unjustified.