Case comparison of sleep features from ear-EEG and scalp-EEG

Abstract

BackgroundWe investigate the potential usability of a novel in-the-ear electroencephalography recording device for sleep staging.MethodsIn one healthy subject we compare simultaneous earelectroencephalography to standard scalp EEG visually and using power spectrograms. Hypnograms independently derived from the records are compared.ResultsWe find that alpha activity, K complexes, sleep spindles and slow wave sleep can be visually distinguished using earelectroencephalography. Spectral peaks are shared between the two records. Hypnograms are 90.9% similar.ConclusionThe results indicate that ear-electroencephalography can be used for sleep staging.

Concealed, Unobtrusive Ear-Centered EEG Acquisition: cEEGrids for Transparent EEG

“…As illustrated in Figure 7, different EEG sleep features comprising theta activity, k-complexes and slow wave sleep could be captured with the cEEGrid. Compared to in-ear EEG (Zibrandtsen et al, 2016) the cEEGrid ear-EEG amplitudes are somewhat larger.…”

“…Traditional sleep EEG recordings use bipolar derivations between a mastoid and a central location (e.g., C4, Campbell, 2009). Recently, Zibrandtsen et al (2016) reported a first case study of sleep staging using ear-EEG and compared ear-EEG and cap-EEG. Although the amplitudes of the ear-EEG recordings were considerably smaller when compared to those derived from cap-EEG channels, ear-EEG may allow for an identification of sleep stages (see also Stochholm et al, 2016).…”

“…By directly comparing simultaneously acquired scalp-EEG and ear-EEG signals, several independent laboratories have shown that ear-EEG can capture brain signals that are closely related to those recorded with scalp-EEG (Mikkelsen et al, 2015; Mirkovic et al, 2015; Bleichner et al, 2016; Zibrandtsen et al, 2016). In contrast to the classical EEG cap, ear-EEG sensors can be worn comfortably and are not more noticeable than hearing-aids or (in-ear) headphones.…”

Development and Characterization of Ear-EEG for Real-Life Brain-Monitoring

“…The ear-EEG could most likely be utilized for the majority of the clinical and research applications mentioned above. This includes more specific applications, such as sleep diagnostics [106], monitoring of impending severe hypoglycemia (SH, insulin shock) in insulin-treated diabetics [53] and monitoring of frequency and length of seizures in childhood absence epilepsy [36]. Studies show that impending SH can be observed in the EEG, and a device enabling constant monitoring of EEG in the everyday life could effectively alarm about an impending SH [53,93].…”

“…Other applications of ear-EEG, which is currently being explored, include sleep stage classification [106] and monitoring of epilepsy. 15 patients under clinical investigations for epilepsy, have been monitored with ear-EEG in an epilepsy monitoring unit at Roskilde Hospital.…”