The Quantitative Electroencephalogram and the Low-Resolution Electrical Tomographic Analysis in Posttraumatic Stress Disorder

Ben Gurion University, Faculty of Health, Beer Sheva, Israel.
Clinical EEG and neuroscience: official journal of the EEG and Clinical Neuroscience Society (ENCS) (Impact Factor: 2.22). 01/2012; 43(1):48-53. DOI: 10.1177/1550059411428716
Source: PubMed


The electroencephalogram (EEG) is the recording of the brain electrical activity as measured on the scalp. Using mathematical algorithms, the 3-dimensional (3D) distribution of the electrical potential inside the brain can be calculated. One of the methods to calculate it is the low-resolution electrical tomographic analysis (LORETA). In this research, we seek to find the brain structures that differentiate patients with posttraumatic stress disorder (PTSD) from controls. Ten right-handed consenting adult male patients were recruited from a PTSD clinic. All patients fulfilled Diagnostic and Statistical Manual of Mental Disorders (Fourth Edition, Text Revision [DSM-IV-TR]) criteria for chronic PTSD (duration >2 years.) and were on drug treatment regimens that had been stable for at least 2 months (involving only serotonin reuptake inhibitors [SSRIs] and benzodiazepines).The control group consisted of 10 healthy hospital staff members. All study participants underwent 19 channel EEG measurements according to current standards of practice. All artifact-free EEG strips were examined for spectral as well as LORETA analysis focusing on the theta (4-7 Hz) band which is suggested to reflect the activity of the limbic system. The theta band showed a statistically significant difference (P < .05) between the 2 groups in the right temporal lobe and in both the right and left frontal lobes. Our findings support existing research data obtained via other imaging technologies, which demonstrated structural alterations in the right temporal and frontal areas in PTSD. These results indicate that combining quantitative EEG (QEEG) and the LORETA method, among other methods, may improve the neuroanatomical resolution of EEG data analysis.

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    • "Non-invasive brain activity recording has been used to investigate anatomical and functional changes occurring in post-traumatic stress disorder (PTSD). Functional studies have described significant neurobiological alterations in patients with PTSD while both reliving psychological traumas (Shin et al., 1999, 2004; Lanius et al., 2002, 2003; Lindauer et al., 2004; Britton et al., 2005; Osuch et al., 2008) and during resting state (Todder et al., 2012; Lee et al., 2014). The brain areas more frequently implicated in PTSD studies (hippocampus, amygdala, medial prefrontal cortex, anterior and posterior cingulate, and temporal cortex; Francati et al., 2007) belong to the limbic system, known to be involved in processing both positive and negative emotions. "
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