Abnormal brain activation during movement observation in patients with conversion paralysis

Neuroimage. 2006 Feb 15;29(4):1336-43. doi: 10.1016/j.neuroimage.2005.08.033. Epub 2005 Oct 5.


Dissociative paralysis in conversion disorders has variably been attributed to a lack of movement initiation or an inhibition of movement. While psychodynamic theory suggests altered movement conceptualization, brain activation associated with observation and replication of movements has so far not been assessed neurobiologically. Here, we measured brain activation by functional magnetic resonance imaging during observation and subsequent imitative execution of movements in four patients with dissociative hand paralysis. Compared to healthy controls conversion disorder patients showed decreased activation of cortical hand areas during movement observation. This effect was specific to the side of their dissociative paralysis. No brain activation compatible with movement inhibition was observed. These findings indicate that in dissociative paralysis, there is not only derangement of movement initiation but already of movement conceptualization. This raises the possibility that strategies targeted at reestablishing appropriate movement conceptualization may contribute to the therapy of dissociative paralysis.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Brain Mapping
  • Cerebral Cortex / physiopathology*
  • Conversion Disorder / diagnosis
  • Conversion Disorder / physiopathology*
  • Conversion Disorder / psychology
  • Dissociative Disorders / diagnosis
  • Dissociative Disorders / physiopathology*
  • Dissociative Disorders / psychology
  • Female
  • Functional Laterality / physiology
  • Hand / innervation*
  • Hemiplegia / diagnosis
  • Hemiplegia / physiopathology*
  • Hemiplegia / psychology
  • Humans
  • Image Interpretation, Computer-Assisted*
  • Imagination / physiology
  • Imaging, Three-Dimensional*
  • Magnetic Resonance Imaging*
  • Male
  • Middle Aged
  • Nerve Net / physiopathology
  • Neurons / physiology
  • Reference Values