Validation of Electroencephalographic Recordings Obtained with a Consumer-Grade, Single Dry Electrode, Low-Cost Device: A Comparative Study

Abstract

The functional validity of the signal obtained with low-cost electroencephalography (EEG) devices is still under debate. Here, we have conducted an in-depth comparison of the EEG-recordings obtained with a medical-grade golden-cup electrodes ambulatory device, the SOMNOwatch + EEG-6, vs those obtained with a consumer-grade, single dry electrode low-cost device, the NeuroSky MindWave, one of the most affordable devices currently available. We recorded EEG signals at Fp1 using the two different devices simultaneously on 21 participants who underwent two experimental phases: a 12-minute resting state task (alternating two cycles of closed/open eyes periods), followed by 60-minute virtual-driving task. We evaluated the EEG recording quality by comparing the similarity between the temporal data series, their spectra, their signal-to-noise ratio, the reliability of EEG measurements (comparing the closed eyes periods), as well as their blink detection rate. We found substantial agreement between signals: whereas, qualitatively, the NeuroSky MindWave presented higher levels of noise and a biphasic shape of blinks, the similarity metric indicated that signals from both recording devices were significantly correlated. While the NeuroSky MindWave was less reliable, both devices had a similar blink detection rate. Overall, the NeuroSky MindWave is noise-limited, but provides stable recordings even through long periods of time. Furthermore, its data would be of adequate quality compared to that of conventional wet electrode EEG devices, except for a potential calibration error and spectral differences at low frequencies.

Single-channel electroencephalography and its associations with anxiety and pain during oral surgery: a preliminary report

“…To our knowledge, this is the first study to use a mobile single-channel EEG device to monitor TMo surgeries; for this reason, there is no comparative method. It should be viewed as an exploratory study with highly interesting points that may direct the development of a new device for identifying biological markers to explore surgical stress in oral surgery; NBSKeeg, used in this research, shows fair validity and reliability, and it has been employed by several clinical studies [ 10 11 12 13 23 24 25 26 ]. Clinical modifications of the initial protocol, such as expanding the EEG monitoring period to cover the full surgery and clinically time-controlling the events of the trans-surgical development, could also be an interesting approach.…”

“…Electroencephalography (EEG) is one of the most commonly used techniques for neurological and psychological assessments, and it has been performed with highly sensitive time-consuming assembly and expensive electronic devices [ 10 11 12 ]. Advances in technology have facilitated the production of mobile and low-cost EEG apparatus and the development of brain-computer interfaces, which, in turn, enable EEG recordings in previously impossible situations [ 10 11 12 ], such as driving, cycling, and undergoing surgery under local anesthesia. Rieiro et al (2019) [ 12 ] compared this form of EEG to medical-grade EEG and observed a substantial agreement between the equipment recordings, indicating that the metrics from both were significantly correlated.…”

“…Advances in technology have facilitated the production of mobile and low-cost EEG apparatus and the development of brain-computer interfaces, which, in turn, enable EEG recordings in previously impossible situations [ 10 11 12 ], such as driving, cycling, and undergoing surgery under local anesthesia. Rieiro et al (2019) [ 12 ] compared this form of EEG to medical-grade EEG and observed a substantial agreement between the equipment recordings, indicating that the metrics from both were significantly correlated. Rogers et al (2016) [ 10 ] assessed the test-retest reliability of a single-channel EEG and concluded that the device may provide a viable alternative to conventional lab-based recording systems for assessing changes in electrophysiological brain signals and suggested that the new system is a potentially sensitive biological marker.…”

Basic Electroencephalogram and Its Common Clinical Applications in Children

“…Electroencephalography EEG, since it's first introduction early in the 20th century, has been an essential and the most common neurophysiological device to monitor and study the electrical and functional activity of the brain [17]. EEG is a commonly used non-invasive tool to track and record the electrical field potentials captured by electrodes placed on the patient scalp.…”

Design of an Interactive Mind Calligraphy System by Affective Computing and Visualization Techniques for Real-Time Reflections of the Writer’s Emotions

“…Considering the EEG being useful for direct reflections of humans’ emotional states with relatively low costs and simplicity, Kim et al [ 28 ] reviewed the computational methods that have been developed to deduct EEG indices of emotion, to extract emotion-related features, or to classify EEG signals into one of many emotional states; mentioned that EEG-based emotional state estimation requires well designed computational methods to extract information from complex and noisy multichannel EEG data; and proposed the use of sequential Bayesian inference to estimate the continuous emotional state in real time. Furthermore, Rieiro et al [ 29 ] conducted an in-depth comparison of the EEG recording qualities of a medical-grade device, the SOMNOwatch + EEG-6, and a consumer-grade device, the NeuroSky MindWave Mobile [ 30 ]; and revealed the fact that though the MindWave Mobile is noise-limited, it provides stable recordings even through long time periods with its data being of adequate quality compared to that of conventional wet electrode EEG devices, except for a potential calibration error and spectral differences at low frequencies.…”