Hemispheric asymmetry in non-linear interdependence of EEG in post-traumatic stress disorder

• Published in: Psychiatry and clinical neurosciences Vol. 66; no. 2; pp. 87 - 96
• Main Authors: Kim, Jinho, Chae, Jeong-Ho, Ko, Hee-kyoung, Latchoumane, Charles-Francois Vincent, Banerjee, Aveek, Mandell, Donald J., Hoven, Christina W., Jeong, Jaeseung
• Format: Journal Article
• Language: English
• Published: Melbourne, Australia Blackwell Publishing Asia 01.03.2012; Wiley-Blackwell
• Subjects: Adult; Adult and adolescent clinical studies; Anxiety disorders. Neuroses; Asymmetry; Biological and medical sciences; Brain - physiopathology; Cortex; Data processing; EEG; electroencephalogram; Electroencephalography; Female; Functional Laterality - physiology; Hemispheric laterality; Humans; Information processing; Male; Medical sciences; Middle Aged; Nerve Net - physiopathology; Neural networks; Neuroimaging; non-linear interdependence; Post-traumatic stress disorder; Psychology. Psychoanalysis. Psychiatry; Psychopathology. Psychiatry; Stress Disorders, Post-Traumatic - physiopathology; post-traumatic stress disorder; Hemispheric specialization; Central nervous system; Anxiety disorder; Electrophysiology; Electroencephalography; Posttraumatic stress disorder; Stress; electroencephalogram; Encephalon; Electrodiagnosis; Asymmetry; non-linear interdependence; Laterality
• ISSN: 1323-1316; 1440-1819; 1440-1819
• DOI: 10.1111/j.1440-1819.2011.02300.x

Aim:  While volumetric and metabolic imaging on post‐traumatic stress disorder (PTSD) patients has been intensively performed, few studies using electroencephalograms (EEG) have been done as yet. The aim of the present study was to investigate abnormalities in functional connectivity of cortical networks in PTSD. Methods:  Non‐linear interdependence (NI), a measure of bidirectional, non‐linear information transmission between two time series, was used. Resting EEG were recorded for 18 PTSD patients and 18 sex‐matched healthy subjects on 16 channels with their eyes closed. Results:  The NI patterns in PTSD patients were hemisphere asymmetric: an increase in NI in the fronto‐parieto‐temporal regions of the left hemisphere (F7, F3, T3, C3, T5 and P3) and a decrease in the fronto‐parieto‐occipital regions of the right hemisphere (F4, C4, P4 and O2). The non‐linearity of NI in EEG, estimated from the surrogate data method, exhibited an increase in the PTSD patients as compared with that of healthy subjects, particularly in the left hemispheric cortex. Conclusion:  Abnormal functional connectivity in PTSD can be assessed using NI, a measure of multi‐channel EEG.