Initially independent lines of research suggest that sleep‐specific brain activity patterns, observed as electroencephalographic slow oscillatory and sleep spindle activity, promote memory consolidation and underlying synaptic refinements. Here, we further tested the emerging concept that specifically the coordinated interplay of slow oscillations and spindle activity (phase‐amplitude coupling) support memory consolidation. Particularly, we associated indices of the interplay between slow oscillatory (0.16–1.25 Hz) and spindle activity (12–16 Hz) during non‐rapid eye movement sleep (strength [modulation index] and phase degree of coupling) in 20 healthy adults with parameters of overnight declarative (word‐list task) and procedural (mirror‐tracing task) memory consolidation. The pattern of results supports the notion that the interplay between oscillations facilitates memory consolidation. The coincidence of the spindle amplitude maximum with the up‐state of the slow oscillation (phase degree) was significantly associated with declarative memory consolidation (r = .65, p = .013), whereas the overall strength of coupling (modulation index) correlated with procedural memory consolidation (r = .45, p = .04). Future studies are needed to test for potential causal effects of the observed association between neural oscillations during sleep and memory consolidation, and to elucidate ways of modulating these processes, for instance through non‐invasive brain‐stimulation techniques.

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Music is capable of inducing emotional arousal. While previous studies used brief musical excerpts to induce one specific emotion, the current study aimed to identify the physiological correlates of continuous changes in subjective emotional states while listening to a complete music piece. A total of 19 participants listened to the first movement of Ludwig van Beethoven's 5th symphony (duration: ~7.4 min), during which a continuous 76-channel EEG was recorded. In a second session, the subjects evaluated their emotional arousal during the listening. A fast fourier transform was performed and covariance maps of spectral power were computed in association with the subjective arousal ratings. Subjective arousal ratings had good inter-individual correlations. Covariance maps showed a right-frontal suppression of lower alpha-band activity during high arousal. The results indicate that music is a powerful arousal-modulating stimulus. The temporal dynamics of the piece are well suited for sequential analysis, and could be necessary in helping unfold the full emotional power of music.