Altered regional activity and inter-regional functional connectivity in psychogenic non-epileptic seizures

Sci Rep. 2015 Jun 25;5:11635. doi: 10.1038/srep11635.

Abstract

Although various imaging studies have focused on detecting the cerebral function underlying psychogenic non-epileptic seizures (PNES), the nature of PNES remains poorly understood. In this study, we combined the resting state fMRI with fractional amplitude of low-frequency fluctuations (fALFF) and functional connectivity based on the seed voxel linear correlation approach to examine the alterations of regional and inter-regional network cerebral functions in PNES. A total of 20 healthy controls and 18 patients were enrolled. The PNES patients showed significantly increased fALFF mainly in the dorsolateral prefrontal cortex (DLPFC), parietal cortices, and motor areas, as well as decreased fALFF in the triangular inferior frontal gyrus. Thus, our results add to literature suggesting abnormalities of neural synchrony in PNES. Moreover, PNES exhibited widespread inter-regional neural network deficits, including increased (DLPFC, sensorimotor, and limbic system) and decreased (ventrolateral prefrontal cortex) connectivity, indicating that changes in the regional cerebral function are related to remote inter-regional network deficits. Correlation analysis results revealed that the connectivity between supplementary motor area and anterior cingulate cortex correlated with the PNES frequency, further suggesting the skewed integration of synchronous activity could predispose to the occurrence of PNES. Our findings provided novel evidence to investigate the pathophysiological mechanisms of PNES.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Brain Mapping / methods
  • Cerebral Cortex / diagnostic imaging
  • Cerebral Cortex / physiopathology*
  • Diagnostic and Statistical Manual of Mental Disorders
  • Electroencephalography
  • Female
  • Gyrus Cinguli / diagnostic imaging
  • Gyrus Cinguli / physiopathology
  • Humans
  • Image Processing, Computer-Assisted / methods*
  • Magnetic Resonance Imaging / methods*
  • Male
  • Motor Cortex / diagnostic imaging
  • Motor Cortex / physiopathology
  • Nerve Net / diagnostic imaging
  • Nerve Net / physiopathology
  • Parietal Lobe / diagnostic imaging
  • Parietal Lobe / physiopathology
  • Prefrontal Cortex / diagnostic imaging
  • Prefrontal Cortex / physiopathology
  • Radiography
  • Seizures / physiopathology*
  • Seizures / psychology
  • Young Adult