Asymmetry in sleep spindles and motor outcome in infants with unilateral brain injury

Abstract

Aim To determine whether interhemispheric difference in sleep spindles in infants with perinatal unilateral brain injury could link to a pathological network reorganization that underpins the development of unilateral cerebral palsy (CP). Method This was a multicentre retrospective study of 40 infants (19 females, 21 males) with unilateral brain injury. Sleep spindles were detected and quantified with an automated algorithm from electroencephalograph records performed at 2 months to 5 months of age. The clinical outcomes after 18 months were compared to spindle power asymmetry (SPA) between hemispheres in different brain regions. Results We found a significantly increased SPA in infants who later developed unilateral CP (n=13, with the most robust interhemispheric difference seen in the central spindles. The best individual‐level prediction of unilateral CP was seen in the centro‐occipital spindles with an overall accuracy of 93%. An empiric cut‐off level for SPA at 0.65 gave a positive predictive value of 100% and a negative predictive value of 93% for later development of unilateral CP. Interpretation Our data suggest that automated analysis of interhemispheric SPA provides a potential biomarker of unilateral CP at a very early age. This holds promise for guiding the early diagnostic process in infants with a perinatally identified brain injury. What this paper adds Unilateral perinatal brain injury may affect the development of electroencephalogram (EEG) sleep spindles. Interhemispheric asymmetry in sleep spindles can be quantified with automated EEG analysis. Spindle power asymmetry can be a potential biomarker of unilateral cerebral palsy.

High‐density neonatal electroencephalography provides biomarkers for developmental trajectories

“…This allows researchers to explore the relative changes in prominence of each frequency band and test hypotheses with regard to their physiological significance 3,4 . Insights into an effect on sleep spindles highlighted by Ventura et al may prove to be highly relevant as this group of rhythmic waves has been recognized as a biomarker of brain function and sleep‐dependent neuroplasticity 5 . The same can be said about interhemispheric coherence, as this may reflect sleep‐ and experience‐dependent neuroplasticity, as well as offer a coarse measure of functional connectivity within the brain.…”

“…How can children with more severe impairment participate? 5 It is not particularly useful anymore to ask whether inclusive schooling is effective, but how can it best be realized? Inclusion has been proved to be the way forward, as the UN has demonstrated.…”