title: Sawtooth wave density analysis during REM sleep in temporal lobe epilepsy patients.
abstract: OBJECTIVE
  This study analyzes sawtooth waves (STW), a characteristic feature of rapid eye movement (REM) sleep, in temporal lobe epilepsy patients in order to test the hypothesis of STW dysfunction in this population.
  
  
  METHODS
  Polysomnographic records from 16 patients with temporal lobe epilepsy and 11 controls were scored for density (STW/h of REM sleep), duration (STW duration in s), and frequency of STW (waves/second within each STW complex). These measures were compared between both groups.
  
  
  RESULTS
  STW measures were significantly different in control vs. epilepsy patients; respectively, density was 60.8 vs. 20.9 waves/h (P<0.005), average duration was 6.5 vs. 5.4 s (P<0.005 cycles 1-4), and frequency was 2.75 vs. 2.61 Hz (P<0.0005 across all cycles).
  
  
  CONCLUSIONS
  Our measurements show a change in the density, duration and frequency of STW in patients with temporal lobe epilepsy compared to controls. Other parameters of REM sleep appear to be similar in both groups. These findings suggest a cortical influence on REM sleep either directly or through limbic-hypothalamic-brainstem connections.
authors.affiliation: EEG Section, NINDS, NIH, Bethesda, MD, USA. fvega@jhu.edu
authors.forename: Francisco
authors.initials: F
authors.lastname: Vega-Bermudez
authors.forename: Sara
authors.initials: S
authors.lastname: Szczepanski
authors.forename: Beth
authors.initials: B
authors.lastname: Malow
authors.forename: Susumu
authors.initials: S
authors.lastname: Sato
mesh_terms: D000293:Adolescent; D000328:Adult; D004833:Epilepsy, Temporal Lobe / Q000175:diagnosis* / Q000503:physiopathology*; D005133:Eye Movements / Q000502:physiology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D017286:Polysomnography / Q000379:methods*; D012895:Sleep, REM / Q000502:physiology*