Abstract: A head mounted medical device for obtaining and processing EEG, EKG, and EOG/EMG signals from a wearer. The device utilizes electrodes organized into multiple electrode assemblies for ease of use and replacement, with the electrode assemblies being removably connected to the headband. The device includes processing and conditioning circuitry in the headband, the processing and conditioning including amplification, filtering, A/D conversion, and multiplexing of the analog signals generated by the electrodes, reducing noise influences and improving the handling and mobility of the device. The device connects to an external receiving device that then monitors and/or records the resulting serial, digital, and multiplexed data signal. The external device might also provide power and/or commands to the medical device.