Promise for Personalized Diagnosis? Assessing the Precision of Wireless Consumer-Grade Electroencephalography across Mental States  
[PERSON]  
1 NICER Lab, Carleton University, Ottawa, ON K1S5B6, Canada;  
[EMAIL_ADDRESS] (G.L.-D.); [EMAIL_ADDRESS] (D.M.B.) 2  
[PERSON]  
1 NICER Lab, Carleton University, Ottawa, ON K1S5B6, Canada;  
[EMAIL_ADDRESS] (G.L.-D.); [EMAIL_ADDRESS] (D.M.B.) 2  
[PERSON]  
1 NICER Lab, Carleton University, Ottawa, ON K1S5B6, Canada;  
[EMAIL_ADDRESS] (G.L.-D.); [EMAIL_ADDRESS] (D.M.B.) 2  
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One challenge in developing outside lab EEG applications, however, is that traditional research- and medical-grade EEG devices are costly (\(\sim\)US$50,000+), typically stationary, fully wired, and time consuming to properly set up, in that electrode application may typically take 30-60 min depending on the type and number of wet (gel-based) sensors [3]. For example, one research-grade EEG device is the Brainvision EEG headset. Its most typical configuration includes 32 channels and must be connected by wires to an amplifier, a computer, and a monitor, for data input and analysis. Its electrodes require the use of electro-conductive gel prior to the experiment, which allows it to minimize impedance and be more sensitive to the electrical activity produced by the brain. While these factors are a strength of Brainvision in regard to the accuracy and reliability of data collection, they can also be interpreted as limitations in other capacities. For instance, all of these factors make using traditional EEG challenging in more ecological settings (i.e., educational and training health settings). In response to these challenges, over the last decade or so, wearable, portable, cost-efficient EEG headsets have been developed [3]. To date, the most recent and exhaustive review of consumer grade EEG devices impressively covering applications in cognition, brain computer interfaces, education research, and game development has been published by [PERSON] et al. [20]. Their review dealt primarily with the validity associated with the wireless EEG devices, that is, with the issues related to whether what was measured by wireless consumer-grade devices reflected the same constructs (for example the same EEG or/and ERP components or signatures) or the same entities/features intended to be identified and measured as the ones traditionally obtained with research-grade EEG devices. However, [PERSON] et al. did not explicitly differentiate issues of validity from those of reliability, therefore, their assessment did not adequately address related issues of personalization, these are the central objective and contribution of our work.  
A commercial consumer-gradeddevice that emerged in response to the limiting factors associated with stationary research-grade systems was the Emotiv EPOC. The EPOC headset is much more affordable; as of fall 2021, the newer 14-channel version of the Emotiv EPOC (now called the Emotiv EPOC X) can be purchased for less than US $1000.