Abnormal coherence and sleep composition in children with Angelman syndrome: a retrospective EEG study.
Hanna den Bakker, Michael S Sidorov, Zheng Fan and 4 others
PMID 29719672WHAT IT FOUND
Children with Angelman syndrome had stronger brain-wave links between distant electrodes during wakefulness and sleep, plus fewer and shorter sleep spindles, brief brain bursts in non-REM sleep.
These exploratory markers may guide future trials, not Monday therapy.
Key findings
01During wakefulness, short-range coherence was not significantly different (p = 0.1887), long-range coherence was increased (p = 0.0207), and the long-range/short-range ratio was increased (p = 0.0016).
02During non-REM sleep, short-range coherence was not significantly different (p = 0.3059), long-range coherence was increased (p = 0.0442), and the increase was specific to gamma (p = 0.0024).
03Automated analysis found fewer sleep spindles (p = 0.0002) and shorter spindles (p < 0.0001) in Angelman syndrome; blinded manual counting showed a significant decrease by one expert (p < 0.0001) and a trend by another (p = 0.0570).
STILL TO COME
How it was doneWhat they foundWhat it means for SLPs
Read the rest of this summary
You get three full summaries a month, free, and we do not ask for a card. Search, the TL;DRs and your library stay unlimited either way.
What it does not show
This was an exploratory retrospective EEG study, not a trial and not a controlled overnight sleep study. Only 13 of 28 children with Angelman syndrome slept during EEG recordings, compared with 54 of 72 neurotypical children. Sleep periods averaged about 14 minutes for controls and 22 minutes for Angelman syndrome, so they may not reflect normal overnight sleep. The EEG findings were not linked to speech, movement, behavior, or daily sleep complaints. Sleep coherence analyses excluded recordings with likely muscle artifact. Manual spindle counting was inconsistent across blinded experts. The coherence and spindle findings were less robust than the known delta-power difference.
Declared interests
The work was funded by the National Institute of Neurological Disorders and Stroke, the Angelman Syndrome Foundation, the Angelman Syndrome Alliance, and the National Institute of Child Health and Human Development. The supplied text does not report author conflicts of interest.
The easy way to misread this
Do not conclude that these EEG patterns diagnose Angelman syndrome or tell a therapist what to treat. They were exploratory biomarker findings, not linked to speech, motor, sleep, or daily function outcomes.