Oscillatory dynamics of perception of emotional sentences in healthy subjects with different severity of depressive symptoms

Abstract

The aim of the study was to investigate the characteristics of the oscillatory dynamics of brain activity during the perception of negative, positive, and neutral sentences in healthy individuals with differing severity of depressive symptoms at the preclinical stage. The study involved 34 healthy people (22 women). The severity of the symptoms of depression was assessed using Beck's Depression Inventory (BDI II). Using independent component analysis and the function of dipfit in the EEGlab software, the EEG was divided into components and their localizations were calculated. To assess the induced responses, event-related spectral perturbations were calculated. The perception of emotional sentences was accompanied by a more pronounced increase in theta rhythm in the group with lower severity of depressive symptoms. The perception of all types of sentences was accompanied by a decrease in beta rhythm in the group with lower severity of depressive symptoms. The effects were localized to the precuneus. The decrease of oscillatory responses in the theta and beta ranges in individuals with a high severity of depressive symptoms suggests a reduction of attention to the emotional content and meaning of the sentences.

Keywords: Depression; EEG; Emotional sentence; Localization of individual components.