Default Mode Network alterations in alexithymia: an EEG power spectra and connectivity study

• DOI: 10.1038/srep36653
• Publication Date: 2016-11-15T10:46:06Z
• Authors: Claudio Imperatori; Giacomo Della Marca; Riccardo Brunetti; Giuseppe Alessio ...; Chiara Massullo; Enrico Maria Valenti; Noemi Amoroso; Giulia Maestoso; Anna Contardi; Benedetto Farina
• Keywords: Adult; Male; Brain Mapping; Adolescent; Models, Neurological; EEG; Power spectra; Functional Connectivity; Alexithymia; Electroencephalography; Gyrus Cinguli; Article; Temporal Lobe; Frontal Lobe; Young Adult; 03 medical and health sciences; 0302 clinical medicine; Parietal Lobe; Surveys and Questionnaires; Neural Pathways; Humans; Female; Affective Symptoms; Nerve Net

AbstractRecent neuroimaging studies have shown that alexithymia is characterized by functional alterations in different brain areas [e.g., posterior cingulate cortex (PCC)], during emotional/social tasks. However, only few data are available about alexithymic cortical networking features during resting state (RS). We have investigated the modifications of electroencephalographic (EEG) power spectra and EEG functional connectivity in the default mode network (DMN) in subjects with alexithymia. Eighteen subjects with alexithymia and eighteen subjects without alexithymia matched for age and gender were enrolled. EEG was recorded during 5 min of RS. EEG analyses were conducted by means of the exact Low Resolution Electric Tomography software (eLORETA). Compared to controls, alexithymic subjects showed a decrease of alpha power in the right PCC. In the connectivity analysis, compared to controls, alexithymic subjects showed a decrease of alpha connectivity between: (i) right anterior cingulate cortex and right PCC, (ii) right frontal lobe and right PCC, and (iii) right parietal lobe and right temporal lobe. Finally, mediation models showed that the association between alexithymia and EEG connectivity values was directed and was not mediated by psychopathology severity. Taken together, our results could reflect the neurophysiological substrate of some core features of alexithymia, such as the impairment in emotional awareness.