Effect of lateralized temporal lobe epilepsy on the default mode network

• Published in: Epilepsy & behavior 2012-11, Vol.25 (3), p.350-357
• Main Authors: Haneef, Zulfi, Lenartowicz, Agatha, Yeh, Hsiang J, Engel, Jerome, Stern, John M
• Format: Article
• Language: English
• Subjects: Adult; Brain Mapping; Cognitive ability; Cortex; Cortex (parietal); Default mode network (DMN); Epilepsy; Epilepsy psychopathology; Epilepsy, Temporal Lobe - pathology; Epilepsy, Temporal Lobe - physiopathology; Epileptic networks; Female; fMRI; Functional connectivity; Functional Laterality - physiology; Hemispheric laterality; Hippocampus; Humans; Image Processing, Computer-Assisted; Magnetic Resonance Imaging; Male; Memory; Middle Aged; Models, Neurological; Neural Pathways - pathology; Neurology; Temporal lobe; Temporal Lobe Epilepsy (TLE); Young Adult
• ISSN: 1525-5050; 1525-5069
• DOI: 10.1016/j.yebeh.2012.07.019

Abstract The default mode network (DMN) is composed of cerebral regions involved in conscious, resting state cognition. The hippocampus is an essential component of this network. Here, the DMN in TLE is compared to control subjects to better understand its involvement in TLE. We performed resting state connectivity analysis using regions of interest (ROIs) in the retrosplenium/precuneus (Rsp/PCUN) and the ventro-medial pre-frontal cortex (vmPFC) in 36 subjects (11 with right TLE, 12 with left TLE, 13 controls) to delineate the posterior and anterior DMN regions respectively. We found reduced connectivity of the posterior to the anterior DMN in patients with both right and left TLE. However, the posterior and anterior networks were found to be individually preserved. Lateralization of TLE affects the DMN with left TLE demonstrating more extensive networks. These DMN changes may be relevant to altered cognition and memory in TLE and may be relevant to right vs. left TLE differences in cognitive involvement.