title: Does the circadian modulation of dream recall modify with age?
abstract: OBJECTIVE
  The ultradian NREM-REM sleep cycle and the circadian modulation of REM sleep sum to generate dreaming. Here we investigated age-related changes in dream recall, number of dreams, and emotional domain characteristics of dreaming during both NREM and REM sleep.
  
  
  METHODS
  Analysis of dream recall and sleep EEG (NREM/REM sleep) during a 40-h multiple nap protocol (150 min of wakefulness and 75 min of sleep) under constant routine conditions.
  
  
  METHODS
  Centre for Chronobiology, Psychiatric Hospital of the University of Basel, Basel, Switzerland.
  
  
  METHODS
  Seventeen young (20-31 years) and 15 older (57-74 years) healthy volunteers
  
  
  METHODS
  N/A.
  
  
  RESULTS
  Dream recall and number of dreams varied significantly across the circadian cycle and between age groups, with older subjects exhibiting fewer dreams (P < 0.05), particularly after naps scheduled during the biological day, closely associated with the circadian rhythm of REM sleep. No significant age differences were observed for the emotional domain of dream content.
  
  
  CONCLUSIONS
  Since aging was associated with attenuated amplitude in the circadian modulation of REM sleep, our data suggest that the age-related decrease in dream recall can result from an attenuated circadian modulation of REM sleep.
authors.affiliation: CAPES Foundation/Ministry of Education of Brazil, Brasilia, Brazil.
authors.forename: Sarah Laxhmi
authors.initials: SL
authors.lastname: Chellappa
authors.forename: Mirjam
authors.initials: M
authors.lastname: Münch
authors.forename: Katharina
authors.initials: K
authors.lastname: Blatter
authors.forename: Vera
authors.initials: V
authors.lastname: Knoblauch
authors.forename: Christian
authors.initials: C
authors.lastname: Cajochen
mesh_terms: D000328:Adult; D000368:Aged; D000375:Aging / Q000502:physiology* / Q000523:psychology; D000704:Analysis of Variance; D002940:Circadian Rhythm / Q000502:physiology*; D004325:Dreams / Q000502:physiology* / Q000523:psychology*; D004644:Emotions / Q000502:physiology; D005260:Female; D006801:Humans; D008297:Male; D011939:Mental Recall / Q000502:physiology*; D008875:Middle Aged; D017286:Polysomnography / Q000379:methods; D012016:Reference Values; D012895:Sleep, REM / Q000502:physiology; D013557:Switzerland; D055815:Young Adult