title: Location specific sleep spindle activity in the early visual areas and perceptual learning.
abstract: Visual perceptual learning (VPL) is consolidated during sleep. However, the underlying neuronal mechanisms of consolidation are not yet fully understood. It has been suggested that the spontaneous brain oscillations that characterize sleep stages are indicative of the consolidation of learning and memory. We investigated whether sleep spindles and/or slow-waves are associated with consolidation of VPL during non-rapid eye movement (NREM) sleep during the first sleep cycle, using magnetoencephalography (MEG), magnetic resonance imaging (MRI), and polysomnography (PSG). We hypothesized that after training, early visual areas will show an increase in slow sigma, fast sigma and/or delta activity, corresponding to slow/fast sleep spindles and slow-waves, respectively. We found that during sleep stage 2, but not during slow-wave sleep, the slow sigma power within the trained region of early visual areas was larger after training compared to baseline, and that the increase was larger in the trained region than in the untrained region. However, neither fast sigma nor delta band power increased significantly after training in either sleep stage. Importantly, performance gains for the trained task were correlated with the difference of power increases in slow sigma activity between the trained and untrained regions. This finding suggests that slow sigma activity plays a critical role in the consolidation of VPL, at least in sleep stage 2 during the first sleep cycle.
authors.affiliation: Laboratory for Cognitive and Perceptual Learning, Department of Cognitive, Linguistic & Psychological Sciences, Brown University, 190 Thayer St, Providence, RI 02912, USA. Electronic address: ji_won_bang@brown.edu.
authors.forename: Ji Won
authors.initials: JW
authors.lastname: Bang
authors.affiliation: Department of Radiology, Massachusetts General Hospital and Harvard Medical School, 55 Fruit St, Boston, MA 02114, USA. Electronic address: o.khalilzadeh@gmail.com.
authors.forename: Omid
authors.initials: O
authors.lastname: Khalilzadeh
authors.affiliation: Athinoula A. Martinos Center for Biomedical Imaging, 149 13th St, Charlestown, MA 02129, USA. Electronic address: msh@nmr.mgh.harvard.edu.
authors.forename: Matti
authors.initials: M
authors.lastname: Hämäläinen
authors.affiliation: Laboratory for Cognitive and Perceptual Learning, Department of Cognitive, Linguistic & Psychological Sciences, Brown University, 190 Thayer St, Providence, RI 02912, USA. Electronic address: takeo_watanabe@brown.edu.
authors.forename: Takeo
authors.initials: T
authors.lastname: Watanabe
authors.affiliation: Laboratory for Cognitive and Perceptual Learning, Department of Cognitive, Linguistic & Psychological Sciences, Brown University, 190 Thayer St, Providence, RI 02912, USA. Electronic address: yuka_sasaki@brown.edu.
authors.forename: Yuka
authors.initials: Y
authors.lastname: Sasaki
mesh_terms: D000328:Adult; D004193:Discrimination Learning / Q000502:physiology*; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D015225:Magnetoencephalography; D008297:Male; D012890:Sleep / Q000502:physiology*; D014793:Visual Cortex / Q000502:physiology*; D014796:Visual Perception / Q000502:physiology*; D055815:Young Adult
keywords: Consolidation; Magnetoencephalography (MEG); Reactivation; Sleep; Sleep spindle; Visual perceptual learning