title: EEG Σ and slow-wave activity during NREM sleep correlate with overnight declarative and procedural memory consolidation.
abstract: Previous studies suggest that sleep-specific brain activity patterns such as sleep spindles and electroencephalographic slow-wave activity contribute to the consolidation of novel memories. The generation of both sleep spindles and slow-wave activity relies on synchronized oscillations in a thalamo-cortical network that might be implicated in synaptic strengthening (spindles) and downscaling (slow-wave activity) during sleep. This study further examined the association between electroencephalographic power during non-rapid eye movement sleep in the spindle (sigma, 12-16 Hz) and slow-wave frequency range (0.1-3.5 Hz) and overnight memory consolidation in 20 healthy subjects (10 men, 27.1 ± 4.6 years). We found that both electroencephalographic sigma power and slow-wave activity were positively correlated with the pre-post-sleep consolidation of declarative (word list) and procedural (mirror-tracing) memories. These results, although only correlative in nature, are consistent with the view that processes of synaptic strengthening (sleep spindles) and synaptic downscaling (slow-wave activity) might act in concert to promote synaptic plasticity and the consolidation of both declarative and procedural memories during sleep.
authors.affiliation: Department of Psychiatry and Psychotherapy, University Medical Center Freiburg, Freiburg, Germany.
authors.forename: Johannes
authors.initials: J
authors.lastname: Holz
authors.forename: Hannah
authors.initials: H
authors.lastname: Piosczyk
authors.forename: Bernd
authors.initials: B
authors.lastname: Feige
authors.forename: Kai
authors.initials: K
authors.lastname: Spiegelhalder
authors.forename: Chiara
authors.initials: C
authors.lastname: Baglioni
authors.forename: Dieter
authors.initials: D
authors.lastname: Riemann
authors.forename: Christoph
authors.initials: C
authors.lastname: Nissen
mesh_terms: D000328:Adult; D001921:Brain / Q000502:physiology*; D004569:Electroencephalography / Q000295:instrumentation / Q000379:methods*; D005260:Female; D006801:Humans; D007858:Learning / Q000502:physiology; D008297:Male; D008568:Memory / Q000502:physiology*; D009483:Neuropsychological Tests; D012890:Sleep / Q000502:physiology*; D013997:Time Factors; D055815:Young Adult