Developmental Changes in Sleep Oscillations during Early Childhood.

Eckehard Olbrich,Peter Achermann,Thomas Rusterholz,Monique K Lebourgeois

doi:10.1155/2017/6160959

Abstract

Although quantitative analysis of the sleep electroencephalogram (EEG) has uncovered important aspects of brain activity during sleep in adolescents and adults, similar findings from preschool-age children remain scarce. This study utilized our time-frequency method to examine sleep oscillations as characteristic features of human sleep EEG. Data were collected from a longitudinal sample of young children (n = 8; 3 males) at ages 2, 3, and 5 years. Following sleep stage scoring, we detected and characterized oscillatory events across age and examined how their features corresponded to spectral changes in the sleep EEG. Results indicated a developmental decrease in the incidence of delta and theta oscillations. Spindle oscillations, however, were almost absent at 2 years but pronounced at 5 years. All oscillatory event changes were stronger during light sleep than slow-wave sleep. Large interindividual differences in sleep oscillations and their characteristics (e.g., “ultrafast” spindle-like oscillations, theta oscillation incidence/frequency) also existed. Changes in delta and spindle oscillations across early childhood may indicate early maturation of the thalamocortical system. Our analytic approach holds promise for revealing novel types of sleep oscillatory events that are specific to periods of rapid normal development across the lifespan and during other times of aberrant changes in neurobehavioral function.

Highlights

The electroencephalogram (EEG) is a fundamental method for identifying sleep/wakefulness states, quantifying sleeprelated cortical activity and assessing sleep regulation
We use Neural Plasticity a time-frequency approach based on adaptive autoregressive models that allows detection of oscillatory events without requiring the definition of prespecified frequency bands and is more sensitive to interindividual differences in the frequencies of oscillatory activity
A recent pharmacological study in humans indicated that different generating mechanisms might underlie fast and slow spindles [36]. How this applies in early childhood remains an open question; our results suggest that considerable thalamocortical remodeling/restructuring may occur during early childhood development

Summary

Introduction

The electroencephalogram (EEG) is a fundamental method for identifying sleep/wakefulness states, quantifying sleeprelated cortical activity and assessing sleep regulation. We use Neural Plasticity a time-frequency approach based on adaptive autoregressive models that allows detection of oscillatory events without requiring the definition of prespecified frequency bands (i.e., known oscillations such as slow waves or sleep spindles) and is more sensitive to interindividual differences in the frequencies of oscillatory activity. Such approaches may be best suited for uncovering oscillatory events that are unique to periods of rapid early neurodevelopmental change, which show high variability and commonly do not unfold linearly but in series of stepwise spurts and plateaus (e.g., [5, 6])

Methods

Results

Discussion

Conclusion