Sleep spindle characteristics in adolescents

Objective: Sleep changes substantially during adolescence; however, our understanding of age-related differences in specific electroencephalographic waveforms during this developmental period is limited.

Method: Sigma power, spindle characteristics and cognitive data were calculated for fast (∼13 Hz) central and slow (∼11 Hz) frontal sleep spindles for a large cross-sectional sample of adolescents (N = 134, aged 12-21 years, from the National Consortium on Alcohol and NeuroDevelopment in Adolescence (NCANDA) study).

Results: Older age (and advanced pubertal development) was associated with lower absolute sigma power and greater fast spindle density, with spindles having a shorter duration and smaller amplitude and occurring at a faster average frequency than at a younger age. Spindle characteristics were not directly associated with cognition. An indirect relationship (age * density) provided some evidence for an association between better episodic memory performance and greater spindle density only for younger adolescents.

Conclusion: Spindle characteristics in adolescents differed according to age, possibly reflecting underlying differences in thalamo-cortical connectivity, and may play a role in episodic memory early in adolescence.

Significance: Sleep spindles may serve as a marker of adolescent development, likely reflecting brain maturational status. Investigating specific spindle characteristics, in addition to sigma power, is necessary to fully characterize spindles during adolescence.