A trait of mind: stability and robustness of sleep across sleep opportunity manipulations during simulated military operational stress

Study Objectives Within-subject stability of certain sleep features across multiple nights is thought to reflect the trait-like behavior of sleep. However, to be considered a trait, a parameter must be both stable and robust. Here, we examined the stability (i.e., across the same sleep opportunity periods) and robustness (i.e., across sleep opportunity periods that varied in duration and timing) of different sleep parameters. Methods Sixty-eight military personnel (14 W) spent 5 nights in the sleep laboratory during a simulated military operational stress protocol. After an adaptation night, participants had an 8-hour sleep opportunity (23:00–07:00) followed by 2 consecutive nights of sleep restriction and disruption which included two 2-hour sleep opportunities (01:00–03:00; 05:00–07:00) and, lastly, another 8-hour sleep opportunity (23:00–07:00). Intra-class correlation coefficients were calculated to examine differences in stability and robustness across different sleep parameters. Results Sleep architecture parameters were less stable and robust than absolute and relative spectral activity parameters. Further, relative spectral activity parameters were less robust than absolute spectral activity. Absolute alpha and sigma activity demonstrated the highest levels of stability that were also robust across sleep opportunities of varying duration and timing. Conclusions Stability and robustness varied across different sleep parameters, but absolute NREM alpha and sigma activity demonstrated robust trait-like behavior across variable sleep opportunities. Reduced stability of other sleep architecture and spectral parameters during shorter sleep episodes as well as across different sleep opportunities has important implications for study design and interpretation.

Emergent timbre and extended techniques in live-electronic music: an analysis of desdobramentos do contínuo performed by audio descriptors

In this article, an analysis of the piece Desdobramentos do contínuo for violoncello and live-electronics is addressed concerning instrumental extended techniques, electroacoustic tape sounds, real-time processing, and their interaction. This is part of a broad research about the computer-aided musical analysis of electroacoustic mu- sic. The objective of the analysis of this piece is to understand the spectral activity of the emergent sound structures, in terms of which events produce huge timbre variations, and to identify timbre subtle nuances that are not percep- tible on a first listen of the work. We conclude comparing the analyses results to the compositional hypotheses pre- sented in the initial sections.

Raised Eyebrows

I'm standing in front of a ‘painting’ by Niki de Saint Phalle called ‘Green Sky’. It happens that I'm standing in front of it in Tokyo where the intense nihon-spectral activity on my eu-retina might indeed make the sky green.