Example methods are disclosed herein that include obtaining electroencephalographic (EEG) data from a subject via a device comprising two or more independently adjustable bands, each of the bands having a plurality of electrodes to detect the electroencephalographic data from a brain of the subject, each band selectively rotatable relative to an adjacent band and each band selectively compressible to increase a force of the electrodes against a head of the subject. The example method also includes converting the EEG data into digital EEG signals and conditioning the digital EEG signals. In addition, the example method includes analyzing the digital EEG signals using one or more analysis protocols to determine a mental characteristic of the subject and transmitting the mental characteristic to an output device.