A novel, wearable, in-ear EEG technology to assess sleep and daytime sleepiness

In-ear EEG has emerged as a promising alternative to traditional sleep studies, offering greater comfort and convenience. Here we share a novel in-ear EEG system, including validation of sleep scoring accuracy in comparing both in-ear EEG and full scalp EEG polysomnography (PSG). We observed a high degree of agreement between in-ear EEG and full-scalp EEG PSG (Cohen's Kappa of 0.76). For the primary MWT endpoint of sleep onset latency (SOL), at the per-subject level (n = 24)—averaging across trials as in standard clinical practice—agreement was good (ICC = 0.71, r = 0.75, MAD = 5.1 min). Among the 37 of 126 trials where both devices detected sleep, agreement was strong (ICC = 0.82, MAD = 1.9 min), with excellent agreement in healthy controls (ICC = 0.95, MAD = 1.2 min). Overall trial-level agreement across all 126 trials was moderate (ICC = 0.55), reflecting 22 discordant trials in which scalp EEG detected sleep but in-ear EEG did not—predominantly brief, subtle N1 transitions in CDH participants.For overnight sleep architecture (n = 16 healthy controls), total sleep time (r = 0.94, ICC = 0.85), sleep efficiency (r = 0.94), and wake after sleep onset (r = 0.93) showed strong agreement, with small systematic biases consistent with reduced N1 detection sensitivity. This supports the ability of in-ear EEG data to detect different sleep stages, monitor the effects of medication on sleep, and assess daytime sleepiness. This paper validates a novel in-ear EEG device designed for enhanced comfort, user-friendly operation, and clinical-grade signal integrity.