title: Working memory in 8 Kleine-Levin syndrome patients: an fMRI study.
abstract: OBJECTIVE
  The objectives of this study were to investigate possible neuropathology behind the Kleine-Levin Syndrome (KLS), a severe form of hypersomnia with onset during adolescence.
  
  
  METHODS
  Functional magnetic resonance imaging (fMRI) applying a verbal working memory task was used in conjunction with a paper-and-pencil version of the task.
  
  
  METHODS
  Eight patients with KLS and 12 healthy volunteers participated in the study.
  
  
  RESULTS
  The results revealed a pattern of increased thalamic activity and reduced frontal activity (involving the anterior cingulate and adjacent prefrontal cortex) while performing a reading span task.
  
  
  CONCLUSIONS
  This finding may explain the clinical symptoms observed in KLS, in that the thalamus is known to be involved in the control of sleep. Given the increasing access to fMRI, this investigation may aid clinicians in the diagnosis of patients suffering from severe forms of hypersomnia.
authors.affiliation: Center for Medical Image Sciences and Visualization, Linköping University, Linköping, Sweden. maria.engstrom@liu.se
authors.forename: Maria
authors.initials: M
authors.lastname: Engström
authors.forename: Patrick
authors.initials: P
authors.lastname: Vigren
authors.forename: Thomas
authors.initials: T
authors.lastname: Karlsson
authors.forename: Anne-Marie
authors.initials: AM
authors.lastname: Landtblom
mesh_terms: D000328:Adult; D001921:Brain / Q000503:physiopathology*; D004292:Dominance, Cerebral / Q000502:physiology; D017352:Echo-Planar Imaging; D005260:Female; D005625:Frontal Lobe / Q000503:physiopathology*; D006179:Gyrus Cinguli / Q000503:physiopathology*; D006801:Humans; D007089:Image Enhancement; D007091:Image Processing, Computer-Assisted; D021621:Imaging, Three-Dimensional; D017593:Kleine-Levin Syndrome / Q000175:diagnosis / Q000503:physiopathology* / Q000523:psychology; D008279:Magnetic Resonance Imaging; D008297:Male; D008570:Memory, Short-Term / Q000502:physiology*; D009415:Nerve Net / Q000503:physiopathology; D010100:Oxygen / Q000097:blood; D017397:Prefrontal Cortex / Q000503:physiopathology*; D013788:Thalamus / Q000503:physiopathology*; D055815:Young Adult
chemical_list: D010100:Oxygen