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.