1. A device for multimodal assessment of a subject's neurological condition, the device comprising: a headset comprising one or more neurological electrodes configured to record the subject's brain electrical signals; a base unit operatively coupled to the headset and configured to acquire results of one or more physiological assessments and/or neurocognitive assessments performed on the subject, the base unit further comprising a processor configured to perform the steps of: extracting quantitative features from the brain electrical signals; extracting quantitative features from the results of the one or more physiological assessments and/or neurocognitive assessments performed on the subject; and applying a multimodal classifier to provide a multi-dimensional evaluation of the subject's neurological condition, wherein the multimodal classifier is configured to combine the extracted quantitative features from the brain electrical signals and extracted quantitative features from the results of the one or more physiological assessments and/or neurocognitive assessments, and further wherein the multimodal classifier is pre-developed and pre-trained using selectable features from a training dataset comprising brain electrical activity data and one or more physiological assessments and/or neurocognitive assessments data obtained from a plurality of individuals in the presence or absence of brain abnormalities.