Imaging the trauma: altered cortical dynamics after repeated traumatic stress

In patients with posttraumatic stress disorder (PTSD), we found evidence of altered systemic cerebral functioning by mapping generators of slow waves produced within circumscribed brain regions. Such focal activities have been associated with lesioned neural circuitry in neurological disorders and more recently also in mental illness. Using magnetoencephalographic (MEG-based) source imaging, we mapped abnormal distributions of generators of slow waves in 97 survivors of organized violence with PTSD in comparison to 97 controls. PTSD patients showed elevated production of focally generated slow waves (1-4Hz), particularly in left temporal brain regions with peak activities in the region of the insular cortex. The left insula has been ascribed a key role in expressing verbal affect, and insular dysfunction could play a key role in the decoupling of emotional from language centers, leading PTSD victims to be caught in the speechless terror of their intrusive memories. Descriptors Delta activity, dipole density, magnetoencephalography (MEG), violence, torture, terror,